let currentMoleculeKey = null;
let atoms = [];
let bonds = [];

let rotX = 0, rotY = 0, panX = 0, panY = 0, zoom = 1.0;
let lastX = 0, lastY = 0, isDragging = false;
let isRotating = true, showLabels = true, autoRotationAngle = 0;
let myFont;

let touchesStart = [];
let initialZoom = 1.0;
let initialPanX = 0, initialPanY = 0;
let initialDist = 0;

let currentLang = 'vi';
// Tăng SCALE lên 85 để không gian rộng rãi, các nguyên tử không bị đè vào nhau
const SCALE = 85;

const TRANSLATIONS = {
    vi: {
        headerTitle: "CẤU TRÚC PHÂN TỬ 3D", headerSub: "HÓA HỌC ABC",
        placeholder: "-- Chọn phân tử --", canvasMsg: "Vui lòng chọn phân tử từ menu",
        btnRotate: "Xoay Tự Động", btnLabels: "Nhãn Nguyên Tố",
        btnSave: "Lưu Ảnh", resCurrent: "Màn hình hiện tại",
        fmtPNG: "PNG", fmtJPG: "JPG",
        optgroups: {
            "opt-inorganic":"Chất vô cơ","opt-hydrocarbons":"Hiđrocacbon",
            "opt-halogen":"Dẫn xuất Halogen","opt-alcohols":"Ancol & Phenol",
            "opt-aldehydes":"Anđehit & Xeton","opt-acids":"Axit Cacboxylic",
            "opt-esters":"Este","opt-amines":"Amin & Hợp chất vòng",
            "opt-carbs":"Cacbohiđrat","opt-amino-acids":"Amino Acids"
        }
    },
    en: {
        headerTitle: "3D MOLECULAR STRUCTURE", headerSub: "HÓA HỌC ABC",
        placeholder: "-- Select Molecule --", canvasMsg: "Please select a molecule from the menu",
        btnRotate: "Auto Rotate", btnLabels: "Atom Labels",
        btnSave: "Save Image", resCurrent: "Current Viewport",
        fmtPNG: "PNG", fmtJPG: "JPG",
        optgroups: {
            "opt-inorganic":"Inorganic substances","opt-hydrocarbons":"Hydrocarbons",
            "opt-halogen":"Halogen derivatives","opt-alcohols":"Alcohols & Phenols",
            "opt-aldehydes":"Aldehydes & Ketones","opt-acids":"Carboxylic acids",
            "opt-esters":"Esters","opt-amines":"Amines & Heterocyclics",
            "opt-carbs":"Carbohydrates","opt-amino-acids":"Amino Acids"
        }
    }
};

const ELEMENTS = {
    H:  { color:[255,255,255], radius:18, textColor:[0,0,0] },
    C:  { color:[90,90,90],    radius:32, textColor:[255,255,255] },
    N:  { color:[48,80,248],   radius:32, textColor:[255,255,255] },
    O:  { color:[255,13,13],   radius:28, textColor:[255,255,255] },
    F:  { color:[144,224,80],  radius:30, textColor:[0,0,0] },
    Cl: { color:[31,240,31],   radius:38, textColor:[0,0,0] },
    S:  { color:[255,255,48],  radius:36, textColor:[0,0,0] },
    P:  { color:[255,128,0],   radius:36, textColor:[0,0,0] }
};

const SINGLE_RING_AROMATIC = [
    "C6H6","C6H5CH3","ethylbenzene","o_xylene","m_xylene","p_xylene",
    "styrene","C6H5OH","C6H5NH2","benzoic_acid", "pyridine", "aspirin"
];
const DOUBLE_RING_AROMATIC = ["naphthalene"];

// =====================================================================
// DATA CÁC CHẤT 
// =====================================================================
const MOLECULE_DATA = {
    // --- VÔ CƠ ---
    "H2":  { atoms:[{e:"H",x:-0.37,y:0,z:0},{e:"H",x:0.37,y:0,z:0}], bonds:[[0,1,1]] },
    "N2":  { atoms:[{e:"N",x:-0.55,y:0,z:0},{e:"N",x:0.55,y:0,z:0}], bonds:[[0,1,3]] },
    "O2":  { atoms:[{e:"O",x:-0.6,y:0,z:0},{e:"O",x:0.6,y:0,z:0}], bonds:[[0,1,2]] },
    "O3": { 
        atoms:[{e:"O",x:0,y:0.4,z:0},{e:"O",x:-1.1,y:-0.2,z:0},{e:"O",x:1.1,y:-0.2,z:0}], 
        bonds:[[0,1,2],[0,2,1]] 
    },
    "F2":  { atoms:[{e:"F",x:-0.55,y:0,z:0},{e:"F",x:0.55,y:0,z:0}], bonds:[[0,1,1]] },
    "Cl2": { atoms:[{e:"Cl",x:-0.8,y:0,z:0},{e:"Cl",x:0.8,y:0,z:0}], bonds:[[0,1,1]] },
    "CO": { 
        atoms:[{e:"C",x:-0.5,y:0,z:0},{e:"O",x:0.6,y:0,z:0}], 
        bonds:[[0,1,3]] 
    },
    "CO2": { 
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:-1.16,y:0,z:0},{e:"O",x:1.16,y:0,z:0}], 
        bonds:[[0,1,2],[0,2,2]] 
    },
    "SO2": { 
        atoms:[{e:"S",x:0,y:0.3,z:0},{e:"O",x:-1.25,y:-0.5,z:0},{e:"O",x:1.25,y:-0.5,z:0}], 
        bonds:[[0,1,2],[0,2,2]] 
    },
    "SO3": { 
        atoms:[{e:"S",x:0,y:0,z:0},{e:"O",x:0,y:1.4,z:0},{e:"O",x:1.21,y:-0.7,z:0},{e:"O",x:-1.21,y:-0.7,z:0}], 
        bonds:[[0,1,2],[0,2,2],[0,3,2]] 
    },
    "HCl": { 
        atoms:[{e:"H",x:-0.64,y:0,z:0},{e:"Cl",x:0.64,y:0,z:0}], 
        bonds:[[0,1,1]] 
    },
    "H2O": { 
        atoms:[{e:"O",x:0,y:0.15,z:0},{e:"H",x:0.76,y:-0.45,z:0},{e:"H",x:-0.76,y:-0.45,z:0}], 
        bonds:[[0,1,1],[0,2,1]] 
    },
    "H2O2": { 
        atoms:[{e:"O",x:-0.7,y:0,z:0.3},{e:"O",x:0.7,y:0,z:-0.3},{e:"H",x:-1.1,y:0.8,z:-0.1},{e:"H",x:1.1,y:-0.8,z:0.1}], 
        bonds:[[0,1,1],[0,2,1],[1,3,1]] 
    },
    "H2S": { 
        atoms:[{e:"S",x:0,y:0.2,z:0},{e:"H",x:0.85,y:-0.65,z:0},{e:"H",x:-0.85,y:-0.65,z:0}], 
        bonds:[[0,1,1],[0,2,1]] 
    },
    "NH3": {
        atoms:[
            {e:"N",x:0.000,y:0.000,z:0.000},
            {e:"H",x:0.000,y:-0.380,z:0.930},
            {e:"H",x:0.805,y:-0.380,z:-0.465},
            {e:"H",x:-0.805,y:-0.380,z:-0.465}
        ],
        bonds:[[0,1,1],[0,2,1],[0,3,1]]
    },
    "H2SO4": {
        atoms:[{e:"S",x:0,y:0,z:0},{e:"O",x:0.87,y:0.87,z:0.87},{e:"O",x:-0.87,y:-0.87,z:0.87},
               {e:"O",x:0.87,y:-0.87,z:-0.87},{e:"O",x:-0.87,y:0.87,z:-0.87},
               {e:"H",x:1.2,y:-1.6,z:-0.3},{e:"H",x:-1.2,y:1.6,z:-0.3}],
        bonds:[[0,1,2],[0,2,2],[0,3,1],[0,4,1],[3,5,1],[4,6,1]]
    },
    "HNO3": {
        atoms:[
            {e:"N",x:0.000,y:0.000,z:0},
            {e:"O",x:1.220,y:0.000,z:0},
            {e:"O",x:-0.610,y:1.057,z:0},
            {e:"O",x:-0.610,y:-1.057,z:0},
            {e:"H",x:-1.570,y:1.057,z:0}
        ],
        bonds:[[0,1,2],[0,2,1],[0,3,2],[2,4,1]]
    },
    "H3PO4": {
        atoms:[{e:"P",x:0,y:0,z:0},{e:"O",x:0,y:1.45,z:0},{e:"O",x:1.2,y:-0.5,z:0.5},
               {e:"O",x:-1.2,y:-0.5,z:0.5},{e:"O",x:0,y:-0.5,z:-1.3},
               {e:"H",x:1.6,y:0.3,z:0.9},{e:"H",x:-1.6,y:0.3,z:0.9},{e:"H",x:0,y:0.3,z:-2.0}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[0,4,1],[2,5,1],[3,6,1],[4,7,1]]
    },

    // --- HYDROCARBONS ---
    "CH4": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"H",x:0.63,y:0.63,z:0.63},{e:"H",x:-0.63,y:-0.63,z:0.63},
               {e:"H",x:-0.63,y:0.63,z:-0.63},{e:"H",x:0.63,y:-0.63,z:-0.63}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "C2H6": {
        atoms:[{e:"C",x:-0.76,y:0,z:0},{e:"C",x:0.76,y:0,z:0},{e:"H",x:-1.1,y:1.0,z:0},
               {e:"H",x:-1.1,y:-0.5,z:0.87},{e:"H",x:-1.1,y:-0.5,z:-0.87},{e:"H",x:1.1,y:-1.0,z:0},
               {e:"H",x:1.1,y:0.5,z:-0.87},{e:"H",x:1.1,y:0.5,z:0.87}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[1,7,1]]
    },
    "C3H8": {
        atoms:[{e:"C",x:0,y:0.4,z:0},{e:"C",x:-1.4,y:-0.4,z:0},{e:"C",x:1.4,y:-0.4,z:0},
               {e:"H",x:0,y:0.9,z:0.88},{e:"H",x:0,y:0.9,z:-0.88},{e:"H",x:-1.4,y:-1.5,z:0},
               {e:"H",x:-1.9,y:-0.05,z:0.88},{e:"H",x:-1.9,y:-0.05,z:-0.88},{e:"H",x:1.4,y:-1.5,z:0},
               {e:"H",x:1.9,y:-0.05,z:0.88},{e:"H",x:1.9,y:-0.05,z:-0.88}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[1,7,1],[2,8,1],[2,9,1],[2,10,1]]
    },
    "nC4H10": {
        atoms:[{e:"C",x:-2.1,y:-0.4,z:0},{e:"C",x:-0.7,y:0.4,z:0},{e:"C",x:0.7,y:-0.4,z:0},{e:"C",x:2.1,y:0.4,z:0},
               {e:"H",x:-2.1,y:-1.5,z:0},{e:"H",x:-2.6,y:-0.05,z:0.88},{e:"H",x:-2.6,y:-0.05,z:-0.88},
               {e:"H",x:-0.7,y:0.9,z:0.88},{e:"H",x:-0.7,y:0.9,z:-0.88},{e:"H",x:0.7,y:-0.9,z:0.88},
               {e:"H",x:0.7,y:-0.9,z:-0.88},{e:"H",x:2.1,y:1.5,z:0},{e:"H",x:2.6,y:0.05,z:0.88},{e:"H",x:2.6,y:0.05,z:-0.88}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[0,4,1],[0,5,1],[0,6,1],[1,7,1],[1,8,1],[2,9,1],[2,10,1],[3,11,1],[3,12,1],[3,13,1]]
    },
    "isoC4H10": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"H",x:0,y:0,z:1.1},{e:"C",x:0,y:1.4,z:-0.5},{e:"C",x:1.2,y:-0.7,z:-0.5},{e:"C",x:-1.2,y:-0.7,z:-0.5},
               {e:"H",x:0,y:1.5,z:-1.6},{e:"H",x:0.9,y:1.9,z:-0.1},{e:"H",x:-0.9,y:1.9,z:-0.1},
               {e:"H",x:1.3,y:-0.7,z:-1.6},{e:"H",x:2.1,y:-0.3,z:-0.1},{e:"H",x:1.3,y:-1.7,z:-0.1},
               {e:"H",x:-1.3,y:-0.7,z:-1.6},{e:"H",x:-2.1,y:-0.3,z:-0.1},{e:"H",x:-1.3,y:-1.7,z:-0.1}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[2,5,1],[2,6,1],[2,7,1],[3,8,1],[3,9,1],[3,10,1],[4,11,1],[4,12,1],[4,13,1]]
    },
    "C2H4": {
        atoms:[{e:"C",x:-0.67,y:0,z:0},{e:"C",x:0.67,y:0,z:0},{e:"H",x:-1.25,y:0.92,z:0},
               {e:"H",x:-1.25,y:-0.92,z:0},{e:"H",x:1.25,y:0.92,z:0},{e:"H",x:1.25,y:-0.92,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[1,4,1],[1,5,1]]
    },
    "C2H2": {
        atoms:[{e:"C",x:-0.6,y:0,z:0},{e:"C",x:0.6,y:0,z:0},{e:"H",x:-1.66,y:0,z:0},{e:"H",x:1.66,y:0,z:0}],
        bonds:[[0,1,3],[0,2,1],[1,3,1]]
    },
    "C3H6_open": {
        atoms:[{e:"C",x:-1.2,y:-0.3,z:0},{e:"C",x:0,y:0.4,z:0},{e:"C",x:1.3,y:-0.1,z:0},
               {e:"H",x:-1.2,y:-1.4,z:0},{e:"H",x:-2.1,y:0.2,z:0},{e:"H",x:0,y:1.5,z:0},
               {e:"H",x:1.3,y:-1.2,z:0},{e:"H",x:1.9,y:0.3,z:0.9},{e:"H",x:1.9,y:0.3,z:-0.9}],
        bonds:[[0,1,2],[1,2,1],[0,3,1],[0,4,1],[1,5,1],[2,6,1],[2,7,1],[2,8,1]]
    },
    "C3H6_ring": {
        atoms:[{e:"C",x:0,y:1.0,z:0},{e:"C",x:0.87,y:-0.5,z:0},{e:"C",x:-0.87,y:-0.5,z:0},
               {e:"H",x:0,y:1.3,z:0.9},{e:"H",x:0,y:1.3,z:-0.9},{e:"H",x:1.1,y:-0.7,z:0.9},
               {e:"H",x:1.1,y:-0.7,z:-0.9},{e:"H",x:-1.1,y:-0.7,z:0.9},{e:"H",x:-1.1,y:-0.7,z:-0.9}],
        bonds:[[0,1,1],[1,2,1],[2,0,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[2,7,1],[2,8,1]]
    },
    "cyclohexane": {
        atoms:[
            {e:"C",x:1.2,y:-0.7,z:0.3},{e:"C",x:1.2,y:0.7,z:-0.3},{e:"C",x:0.0,y:1.4,z:0.3},
            {e:"C",x:-1.2,y:0.7,z:-0.3},{e:"C",x:-1.2,y:-0.7,z:0.3},{e:"C",x:0.0,y:-1.4,z:-0.3},
            {e:"H",x:2.1,y:-1.1,z:-0.2},{e:"H",x:1.2,y:-0.7,z:1.4},{e:"H",x:2.1,y:1.1,z:0.2},
            {e:"H",x:1.2,y:0.7,z:-1.4},{e:"H",x:0.0,y:2.5,z:-0.2},{e:"H",x:0.0,y:1.4,z:1.4},
            {e:"H",x:-2.1,y:1.1,z:0.2},{e:"H",x:-1.2,y:0.7,z:-1.4},{e:"H",x:-2.1,y:-1.1,z:-0.2},
            {e:"H",x:-1.2,y:-0.7,z:1.4},{e:"H",x:0.0,y:-2.5,z:0.2},{e:"H",x:0.0,y:-1.4,z:-1.4}
        ],
        bonds:[
            [0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],
            [0,6,1],[0,7,1],[1,8,1],[1,9,1],[2,10,1],[2,11,1],
            [3,12,1],[3,13,1],[4,14,1],[4,15,1],[5,16,1],[5,17,1]
        ]
    },
    "cis_but_2_ene": {
        atoms:[{e:"C",x:-0.67,y:0,z:0},{e:"C",x:0.67,y:0,z:0},{e:"C",x:-1.5,y:1.2,z:0},{e:"C",x:1.5,y:1.2,z:0},
               {e:"H",x:-1.2,y:-0.9,z:0},{e:"H",x:1.2,y:-0.9,z:0},{e:"H",x:-1.2,y:1.8,z:0.9},
               {e:"H",x:-1.2,y:1.8,z:-0.9},{e:"H",x:-2.5,y:0.9,z:0},{e:"H",x:1.2,y:1.8,z:0.9},
               {e:"H",x:1.2,y:1.8,z:-0.9},{e:"H",x:2.5,y:0.9,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,4,1],[1,3,1],[1,5,1],[2,6,1],[2,7,1],[2,8,1],[3,9,1],[3,10,1],[3,11,1]]
    },
    "trans_but_2_ene": {
        atoms:[{e:"C",x:-0.67,y:0,z:0},{e:"C",x:0.67,y:0,z:0},{e:"C",x:-1.5,y:1.2,z:0},{e:"C",x:1.5,y:-1.2,z:0},
               {e:"H",x:-1.2,y:-0.9,z:0},{e:"H",x:1.2,y:0.9,z:0},{e:"H",x:-1.2,y:1.8,z:0.9},
               {e:"H",x:-1.2,y:1.8,z:-0.9},{e:"H",x:-2.5,y:0.9,z:0},{e:"H",x:1.2,y:-1.8,z:0.9},
               {e:"H",x:1.2,y:-1.8,z:-0.9},{e:"H",x:2.5,y:-0.9,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,4,1],[1,3,1],[1,5,1],[2,6,1],[2,7,1],[2,8,1],[3,9,1],[3,10,1],[3,11,1]]
    },
    "but_1_3_diene": {
        atoms:[{e:"C",x:-1.9,y:-0.5,z:0},{e:"C",x:-0.7,y:0.2,z:0},{e:"C",x:0.7,y:-0.2,z:0},{e:"C",x:1.9,y:0.5,z:0},
               {e:"H",x:-1.9,y:-1.5,z:0},{e:"H",x:-2.8,y:0.0,z:0},{e:"H",x:-0.7,y:1.2,z:0},
               {e:"H",x:0.7,y:-1.2,z:0},{e:"H",x:1.9,y:1.5,z:0},{e:"H",x:2.8,y:0.0,z:0}],
        bonds:[[0,1,2],[1,2,1],[2,3,2],[0,4,1],[0,5,1],[1,6,1],[2,7,1],[3,8,1],[3,9,1]]
    },
    "isoprene": {
        atoms:[{e:"C",x:-1.9,y:-0.5,z:0},{e:"C",x:-0.7,y:0.2,z:0},{e:"C",x:0.7,y:-0.2,z:0},{e:"C",x:1.9,y:0.5,z:0},
               {e:"C",x:-0.7,y:1.7,z:0},{e:"H",x:-1.9,y:-1.5,z:0},{e:"H",x:-2.8,y:0.0,z:0},
               {e:"H",x:0.7,y:-1.2,z:0},{e:"H",x:1.9,y:1.5,z:0},{e:"H",x:2.8,y:0.0,z:0},
               {e:"H",x:-1.7,y:2.1,z:0},{e:"H",x:-0.2,y:2.1,z:0.9},{e:"H",x:-0.2,y:2.1,z:-0.9}],
        bonds:[[0,1,2],[1,2,1],[2,3,2],[1,4,1],[0,5,1],[0,6,1],[2,7,1],[3,8,1],[3,9,1],[4,10,1],[4,11,1],[4,12,1]]
    },
    "C6H6": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"H",x:2.48,y:0,z:0},{e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},
               {e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[1,7,1],[2,8,1],[3,9,1],[4,10,1],[5,11,1]]
    },
    "C6H5CH3": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},
               {e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"H",x:3.3,y:1.0,z:0},{e:"H",x:3.3,y:-0.5,z:0.87},{e:"H",x:3.3,y:-0.5,z:-0.87}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[1,7,1],[2,8,1],[3,9,1],[4,10,1],[5,11,1],[6,12,1],[6,13,1],[6,14,1]]
    },
    "ethylbenzene": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"C",x:3.6,y:1.3,z:0},
               {e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},
               {e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"H",x:2.9,y:-0.6,z:0.87},{e:"H",x:2.9,y:-0.6,z:-0.87},
               {e:"H",x:4.6,y:1.3,z:0},{e:"H",x:3.3,y:1.9,z:0.87},{e:"H",x:3.3,y:1.9,z:-0.87}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[6,7,1],[1,8,1],[2,9,1],[3,10,1],[4,11,1],[5,12,1],[6,13,1],[6,14,1],[7,15,1],[7,16,1],[7,17,1]]
    },
    "o_xylene": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"C",x:1.45,y:2.51,z:0},
               {e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"H",x:3.3,y:1.0,z:0},{e:"H",x:3.3,y:-0.5,z:0.87},{e:"H",x:3.3,y:-0.5,z:-0.87},
               {e:"H",x:0.78,y:3.35,z:0},{e:"H",x:2.08,y:2.6,z:0.87},{e:"H",x:2.08,y:2.6,z:-0.87}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[1,7,1],[2,8,1],[3,9,1],[4,10,1],[5,11,1],[6,12,1],[6,13,1],[6,14,1],[7,15,1],[7,16,1],[7,17,1]]
    },
    "m_xylene": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"C",x:-1.45,y:2.51,z:0},
               {e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"H",x:3.3,y:1.0,z:0},{e:"H",x:3.3,y:-0.5,z:0.87},{e:"H",x:3.3,y:-0.5,z:-0.87},
               {e:"H",x:-0.78,y:3.35,z:0},{e:"H",x:-2.08,y:2.6,z:0.87},{e:"H",x:-2.08,y:2.6,z:-0.87}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[2,7,1],[1,8,1],[3,9,1],[4,10,1],[5,11,1],[6,12,1],[6,13,1],[6,14,1],[7,15,1],[7,16,1],[7,17,1]]
    },
    "p_xylene": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"C",x:-2.9,y:0,z:0},
               {e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"H",x:3.3,y:1.0,z:0},{e:"H",x:3.3,y:-0.5,z:0.87},{e:"H",x:3.3,y:-0.5,z:-0.87},
               {e:"H",x:-3.3,y:-1.0,z:0},{e:"H",x:-3.3,y:0.5,z:0.87},{e:"H",x:-3.3,y:0.5,z:-0.87}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[3,7,1],[1,8,1],[2,9,1],[4,10,1],[5,11,1],[6,12,1],[6,13,1],[6,14,1],[7,15,1],[7,16,1],[7,17,1]]
    },
    "styrene": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},
               {e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"C",x:2.8,y:0,z:0},{e:"H",x:3.3,y:-0.9,z:0},{e:"C",x:3.6,y:1.1,z:0},
               {e:"H",x:3.2,y:2.1,z:0},{e:"H",x:4.7,y:1.0,z:0}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[1,6,1],[2,7,1],[3,8,1],[4,9,1],[5,10,1],[0,11,1],[11,12,1],[11,13,2],[13,14,1],[13,15,1]]
    },
    "naphthalene": {
        atoms:[
            {e:"C",x:0,y:0.7,z:0},{e:"C",x:0,y:-0.7,z:0},
            {e:"C",x:1.21,y:1.4,z:0},{e:"C",x:2.42,y:0.7,z:0},
            {e:"C",x:2.42,y:-0.7,z:0},{e:"C",x:1.21,y:-1.4,z:0},
            {e:"C",x:-1.21,y:1.4,z:0},{e:"C",x:-2.42,y:0.7,z:0},
            {e:"C",x:-2.42,y:-0.7,z:0},{e:"C",x:-1.21,y:-1.4,z:0},
            {e:"H",x:1.21,y:2.48,z:0},{e:"H",x:3.36,y:1.24,z:0},
            {e:"H",x:3.36,y:-1.24,z:0},{e:"H",x:1.21,y:-2.48,z:0},
            {e:"H",x:-1.21,y:2.48,z:0},{e:"H",x:-3.36,y:1.24,z:0},
            {e:"H",x:-3.36,y:-1.24,z:0},{e:"H",x:-1.21,y:-2.48,z:0}
        ],
        bonds:[
            [0,1,1],[0,2,1],[2,3,1],[3,4,1],[4,5,1],[5,1,1],
            [1,9,1],[9,8,1],[8,7,1],[7,6,1],[6,0,1],
            [2,10,1],[3,11,1],[4,12,1],[5,13,1],[6,14,1],[7,15,1],[8,16,1],[9,17,1]
        ]
    },

    // --- HALOGEN DERIVATIVES ---
    "CH3Cl": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"Cl",x:0,y:1.5,z:0},{e:"H",x:0.96,y:-0.5,z:0},{e:"H",x:-0.48,y:-0.5,z:0.84},{e:"H",x:-0.48,y:-0.5,z:-0.84}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "CH2Cl2": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"H",x:0.63,y:0.63,z:0.63},{e:"H",x:-0.63,y:-0.63,z:0.63},{e:"Cl",x:1.01,y:-1.01,z:-1.01},{e:"Cl",x:-1.01,y:1.01,z:-1.01}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "CHCl3": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"H",x:0,y:1.09,z:0},{e:"Cl",x:0,y:-0.58,z:1.65},{e:"Cl",x:1.43,y:-0.58,z:-0.825},{e:"Cl",x:-1.43,y:-0.58,z:-0.825}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "CCl4": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"Cl",x:1.01,y:1.01,z:1.01},{e:"Cl",x:-1.01,y:-1.01,z:1.01},{e:"Cl",x:1.01,y:-1.01,z:-1.01},{e:"Cl",x:-1.01,y:1.01,z:-1.01}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "CCl2F2": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"Cl",x:1.01,y:1.01,z:1.01},{e:"Cl",x:-1.01,y:-1.01,z:1.01},{e:"F",x:0.78,y:-0.78,z:-0.78},{e:"F",x:-0.78,y:0.78,z:-0.78}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1]]
    },
    "C2H5Cl": {
        atoms:[{e:"C",x:-0.8,y:0,z:0},{e:"C",x:0.7,y:0,z:0},{e:"H",x:-1.15,y:1.03,z:0},{e:"H",x:-1.15,y:-0.51,z:0.89},{e:"H",x:-1.15,y:-0.51,z:-0.89},{e:"Cl",x:1.4,y:-1.2,z:0},{e:"H",x:1.1,y:0.5,z:0.89},{e:"H",x:1.1,y:0.5,z:-0.89}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[1,7,1]]
    },
    "vinyl_chloride": {
        atoms:[{e:"C",x:-0.67,y:0,z:0},{e:"C",x:0.67,y:0,z:0},{e:"H",x:-1.25,y:0.92,z:0},{e:"H",x:-1.25,y:-0.92,z:0},{e:"H",x:1.25,y:0.92,z:0},{e:"Cl",x:1.61,y:-1.49,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[1,4,1],[1,5,1]]
    },
    "1_chloropropane": {
        atoms:[{e:"C",x:0,y:0.4,z:0},{e:"C",x:-1.4,y:-0.4,z:0},{e:"C",x:1.4,y:-0.4,z:0},
               {e:"H",x:0,y:0.9,z:0.88},{e:"H",x:0,y:0.9,z:-0.88},{e:"H",x:-1.4,y:-1.5,z:0},
               {e:"H",x:-1.9,y:-0.05,z:0.88},{e:"H",x:-1.9,y:-0.05,z:-0.88},
               {e:"H",x:1.4,y:-1.5,z:0},{e:"H",x:1.9,y:-0.05,z:0.88},{e:"Cl",x:2.2,y:0.2,z:-1.4}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[1,7,1],[2,8,1],[2,9,1],[2,10,1]]
    },
    "2_chloropropane": {
        atoms:[{e:"C",x:0,y:0.4,z:0},{e:"C",x:-1.4,y:-0.4,z:0},{e:"C",x:1.4,y:-0.4,z:0},
               {e:"Cl",x:0,y:1.26,z:1.52},{e:"H",x:0,y:0.9,z:-0.88},
               {e:"H",x:-1.4,y:-1.5,z:0},{e:"H",x:-1.9,y:-0.05,z:0.88},{e:"H",x:-1.9,y:-0.05,z:-0.88},
               {e:"H",x:1.4,y:-1.5,z:0},{e:"H",x:1.9,y:-0.05,z:0.88},{e:"H",x:1.9,y:-0.05,z:-0.88}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[1,7,1],[2,8,1],[2,9,1],[2,10,1]]
    },

    // --- ALCOHOLS & PHENOLS ---
    "CH3OH": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:1.42,y:0,z:0},{e:"H",x:-0.37,y:1.03,z:0},{e:"H",x:-0.37,y:-0.51,z:0.89},{e:"H",x:-0.37,y:-0.51,z:-0.89},{e:"H",x:1.7,y:0.8,z:0}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[1,5,1]]
    },
    "C2H5OH": {
        atoms:[{e:"C",x:-1.2,y:0.5,z:0},{e:"C",x:0,y:-0.3,z:0},{e:"O",x:1.2,y:0.5,z:0},
               {e:"H",x:-1.2,y:1.55,z:0},{e:"H",x:-1.7,y:0.15,z:0.89},{e:"H",x:-1.7,y:0.15,z:-0.89},
               {e:"H",x:0,y:-0.95,z:0.89},{e:"H",x:0,y:-0.95,z:-0.89},{e:"H",x:1.9,y:0.0,z:0}],
        bonds:[[0,1,1],[1,2,1],[0,3,1],[0,4,1],[0,5,1],[1,6,1],[1,7,1],[2,8,1]]
    },
    "propan_2_ol": {
        atoms:[{e:"C",x:0,y:0.2,z:0},{e:"C",x:-1.3,y:-0.5,z:0},{e:"C",x:1.3,y:-0.5,z:0},
               {e:"O",x:0,y:1.0,z:1.0},{e:"H",x:0,y:1.8,z:0.7},{e:"H",x:0,y:0.8,z:-0.9},
               {e:"H",x:-1.3,y:-1.6,z:0},{e:"H",x:-1.9,y:-0.1,z:0.88},{e:"H",x:-1.9,y:-0.1,z:-0.88},
               {e:"H",x:1.3,y:-1.6,z:0},{e:"H",x:1.9,y:-0.1,z:0.88},{e:"H",x:1.9,y:-0.1,z:-0.88}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[3,4,1],[0,5,1],[1,6,1],[1,7,1],[1,8,1],[2,9,1],[2,10,1],[2,11,1]]
    },
    "ethane_1_2_diol": {
        atoms:[{e:"C",x:-0.76,y:0,z:0},{e:"C",x:0.76,y:0,z:0},{e:"O",x:-1.22,y:1.36,z:0},{e:"H",x:-2.22,y:1.36,z:0},
               {e:"H",x:-1.1,y:-0.5,z:0.87},{e:"H",x:-1.1,y:-0.5,z:-0.87},{e:"O",x:1.22,y:-1.36,z:0},
               {e:"H",x:2.22,y:-1.36,z:0},{e:"H",x:1.1,y:0.5,z:0.87},{e:"H",x:1.1,y:0.5,z:-0.87}],
        bonds:[[0,1,1],[0,2,1],[2,3,1],[0,4,1],[0,5,1],[1,6,1],[6,7,1],[1,8,1],[1,9,1]]
    },
    "C3H5(OH)3": {
        atoms:[{e:"C",x:-1.5,y:0,z:0},{e:"C",x:0,y:0.8,z:0},{e:"C",x:1.5,y:0,z:0},
               {e:"H",x:-1.5,y:-0.6,z:0.9},{e:"H",x:-1.5,y:-0.6,z:-0.9},{e:"H",x:0,y:1.4,z:0.9},
               {e:"H",x:1.5,y:-0.6,z:0.9},{e:"H",x:1.5,y:-0.6,z:-0.9},
               {e:"O",x:-2.6,y:0.8,z:0},{e:"H",x:-3.3,y:0.3,z:0},
               {e:"O",x:0,y:1.6,z:-1.2},{e:"H",x:0.8,y:2.0,z:-1.2},
               {e:"O",x:2.6,y:0.8,z:0},{e:"H",x:3.3,y:0.3,z:0}],
        bonds:[[0,1,1],[1,2,1],[0,3,1],[0,4,1],[0,8,1],[8,9,1],[1,5,1],[1,10,1],[10,11,1],[2,6,1],[2,7,1],[2,12,1],[12,13,1]]
    },
    "C6H5OH": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"O",x:2.7,y:0,z:0},{e:"H",x:3.05,y:0.88,z:0},{e:"H",x:1.24,y:2.15,z:0},
               {e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[6,7,1],[1,8,1],[2,9,1],[3,10,1],[4,11,1],[5,12,1]]
    },

    // --- ALDEHYDES & KETONES ---
    "HCHO": {
        atoms:[{e:"C",x:0,y:0.2,z:0},{e:"O",x:0,y:-1.0,z:0},{e:"H",x:0.96,y:0.75,z:0},{e:"H",x:-0.96,y:0.75,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,3,1]]
    },
    "CH3CHO": {
        atoms:[{e:"C",x:-0.6,y:-0.2,z:0},{e:"C",x:0.8,y:0.3,z:0},{e:"O",x:-1.6,y:0.3,z:0},
               {e:"H",x:-0.6,y:-1.3,z:0},{e:"H",x:0.9,y:1.4,z:0},{e:"H",x:1.3,y:-0.05,z:0.88},{e:"H",x:1.3,y:-0.05,z:-0.88}],
        bonds:[[0,1,1],[0,2,2],[0,3,1],[1,4,1],[1,5,1],[1,6,1]]
    },
    "CH3COCH3": {
        atoms:[{e:"C",x:0,y:0.4,z:0},{e:"O",x:0,y:1.6,z:0},{e:"C",x:-1.4,y:-0.4,z:0},{e:"C",x:1.4,y:-0.4,z:0},
               {e:"H",x:-1.4,y:-1.5,z:0},{e:"H",x:-1.9,y:-0.05,z:0.88},{e:"H",x:-1.9,y:-0.05,z:-0.88},
               {e:"H",x:1.4,y:-1.5,z:0},{e:"H",x:1.9,y:-0.05,z:0.88},{e:"H",x:1.9,y:-0.05,z:-0.88}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[2,4,1],[2,5,1],[2,6,1],[3,7,1],[3,8,1],[3,9,1]]
    },
    "butanone": {
        atoms:[{e:"C",x:-1.5,y:0.5,z:0},{e:"C",x:0,y:-0.3,z:0},{e:"C",x:1.5,y:0.5,z:0},{e:"C",x:2.8,y:-0.3,z:0},
               {e:"O",x:0,y:-1.5,z:0},{e:"H",x:-1.5,y:1.6,z:0},{e:"H",x:-2.0,y:0.1,z:0.9},{e:"H",x:-2.0,y:0.1,z:-0.9},
               {e:"H",x:1.5,y:1.1,z:0.9},{e:"H",x:1.5,y:1.1,z:-0.9},{e:"H",x:2.8,y:-1.4,z:0},
               {e:"H",x:3.3,y:0.1,z:0.9},{e:"H",x:3.3,y:0.1,z:-0.9}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[1,4,2],[0,5,1],[0,6,1],[0,7,1],[2,8,1],[2,9,1],[3,10,1],[3,11,1],[3,12,1]]
    },

    // --- CARBOXYLIC ACIDS ---
    "HCOOH": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.2,z:0},{e:"O",x:1.2,y:-0.5,z:0},{e:"H",x:2.0,y:-0.1,z:0},{e:"H",x:-1.0,y:-0.5,z:0}],
        bonds:[[0,1,2],[0,2,1],[2,3,1],[0,4,1]]
    },
    "CH3COOH": {
        atoms:[{e:"C",x:0.6,y:0,z:0},{e:"C",x:-0.8,y:0,z:0},{e:"O",x:1.2,y:1.1,z:0},{e:"O",x:1.3,y:-1.1,z:0},
               {e:"H",x:2.2,y:-0.9,z:0},{e:"H",x:-1.2,y:1.0,z:0},{e:"H",x:-1.2,y:-0.5,z:0.87},{e:"H",x:-1.2,y:-0.5,z:-0.87}],
        bonds:[[0,1,1],[0,2,2],[0,3,1],[3,4,1],[1,5,1],[1,6,1],[1,7,1]]
    },
    "CH2=CHCOOH": {
        atoms:[{e:"C",x:-1.8,y:-0.5,z:0},{e:"C",x:-0.6,y:0.2,z:0},{e:"C",x:0.7,y:-0.2,z:0},
               {e:"O",x:1.1,y:-1.3,z:0},{e:"O",x:1.6,y:0.8,z:0},{e:"H",x:-1.9,y:-1.5,z:0},
               {e:"H",x:-2.7,y:0.1,z:0},{e:"H",x:-0.5,y:1.2,z:0},{e:"H",x:2.5,y:0.5,z:0}],
        bonds:[[0,1,2],[1,2,1],[2,3,2],[2,4,1],[0,5,1],[0,6,1],[1,7,1],[4,8,1]]
    },
    "lactic_acid": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"H",x:0,y:1.1,z:0},{e:"C",x:-1.4,y:-0.5,z:0.5},
               {e:"O",x:0.8,y:-0.5,z:1.0},{e:"C",x:0.5,y:-0.3,z:-1.4},{e:"H",x:0.5,y:0,z:1.8},
               {e:"H",x:-2.1,y:0.1,z:0.1},{e:"H",x:-1.4,y:-1.5,z:0.1},{e:"H",x:-1.6,y:-0.4,z:1.6},
               {e:"O",x:1.5,y:0.3,z:-1.8},{e:"O",x:-0.2,y:-1.1,z:-2.1},{e:"H",x:0.2,y:-1.3,z:-2.9}],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[0,4,1],[3,5,1],[2,6,1],[2,7,1],[2,8,1],[4,9,2],[4,10,1],[10,11,1]]
    },
    "oxalic_acid": {
        atoms:[{e:"C",x:-0.7,y:0,z:0},{e:"C",x:0.7,y:0,z:0},{e:"O",x:-1.3,y:1.1,z:0},{e:"O",x:-1.4,y:-1.1,z:0},{e:"H",x:-2.3,y:-0.9,z:0},{e:"O",x:1.3,y:-1.1,z:0},{e:"O",x:1.4,y:1.1,z:0},{e:"H",x:2.3,y:0.9,z:0}],
        bonds:[[0,1,1],[0,2,2],[0,3,1],[3,4,1],[1,5,2],[1,6,1],[6,7,1]]
    },
    "malonic_acid": {
        atoms:[{e:"C",x:0,y:0.5,z:0},{e:"H",x:0,y:1.0,z:0.89},{e:"H",x:0,y:1.0,z:-0.89},
               {e:"C",x:-1.3,y:-0.4,z:0},{e:"O",x:-1.3,y:-1.6,z:0},{e:"O",x:-2.5,y:0.2,z:0},{e:"H",x:-3.2,y:-0.4,z:0},
               {e:"C",x:1.3,y:-0.4,z:0},{e:"O",x:1.3,y:-1.6,z:0},{e:"O",x:2.5,y:0.2,z:0},{e:"H",x:3.2,y:-0.4,z:0}],
        bonds:[[0,3,1],[0,7,1],[0,1,1],[0,2,1],[3,4,2],[3,5,1],[5,6,1],[7,8,2],[7,9,1],[9,10,1]]
    },
    "succinic_acid": {
        atoms:[{e:"C",x:-0.7,y:0.5,z:0},{e:"C",x:0.7,y:-0.5,z:0},{e:"H",x:-0.7,y:1.0,z:0.89},{e:"H",x:-0.7,y:1.0,z:-0.89},{e:"H",x:0.7,y:-1.0,z:0.89},{e:"H",x:0.7,y:-1.0,z:-0.89},{e:"C",x:-2.0,y:-0.4,z:0},{e:"O",x:-2.0,y:-1.6,z:0},{e:"O",x:-3.2,y:0.2,z:0},{e:"H",x:-3.9,y:-0.4,z:0},{e:"C",x:2.0,y:0.4,z:0},{e:"O",x:2.0,y:1.6,z:0},{e:"O",x:3.2,y:-0.2,z:0},{e:"H",x:3.9,y:0.4,z:0}],
        bonds:[[0,1,1],[0,6,1],[1,10,1],[0,2,1],[0,3,1],[1,4,1],[1,5,1],[6,7,2],[6,8,1],[8,9,1],[10,11,2],[10,12,1],[12,13,1]]
    },
    "citric_acid": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.4,z:0},{e:"H",x:0.8,y:1.6,z:0},{e:"C",x:-1.2,y:-0.8,z:-0.8},{e:"O",x:-1.4,y:-0.6,z:-1.9},{e:"O",x:-2.0,y:-1.5,z:-0.2},{e:"H",x:-2.7,y:-1.9,z:-0.6},{e:"C",x:1.2,y:-0.8,z:-0.8},{e:"H",x:1.0,y:-1.8,z:-0.8},{e:"H",x:1.5,y:-0.5,z:-1.8},{e:"C",x:2.5,y:-0.5,z:0.1},{e:"O",x:3.0,y:0.6,z:0.1},{e:"O",x:3.0,y:-1.5,z:0.8},{e:"H",x:3.8,y:-1.3,z:1.2},{e:"C",x:0,y:-0.5,z:1.4},{e:"H",x:-0.9,y:-0.3,z:1.9},{e:"H",x:0.9,y:-0.3,z:1.9},{e:"C",x:0,y:-2.0,z:1.6},{e:"O",x:-1.0,y:-2.6,z:1.8},{e:"O",x:1.1,y:-2.6,z:1.8},{e:"H",x:1.0,y:-3.5,z:1.9}],
        bonds:[[0,1,1],[1,2,1],[0,3,1],[3,4,2],[3,5,1],[5,6,1],[0,7,1],[7,8,1],[7,9,1],[7,10,1],[10,11,2],[10,12,1],[12,13,1],[0,14,1],[14,15,1],[14,16,1],[14,17,1],[17,18,2],[17,19,1],[19,20,1]]
    },
    "benzoic_acid": {
        atoms:[{e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
               {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
               {e:"H",x:1.24,y:2.15,z:0},{e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},
               {e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
               {e:"C",x:2.9,y:0,z:0},{e:"O",x:3.6,y:1.1,z:0},{e:"O",x:3.5,y:-1.1,z:0},{e:"H",x:4.4,y:-1.0,z:0}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[1,6,1],[2,7,1],[3,8,1],[4,9,1],[5,10,1],[0,11,1],[11,12,2],[11,13,1],[13,14,1]]
    },
    "aspirin": {
        atoms:[
            {e:"C",x:1.4,y:0,z:0},{e:"C",x:0.7,y:1.21,z:0},{e:"C",x:-0.7,y:1.21,z:0},
            {e:"C",x:-1.4,y:0,z:0},{e:"C",x:-0.7,y:-1.21,z:0},{e:"C",x:0.7,y:-1.21,z:0},
            {e:"H",x:-1.24,y:2.15,z:0},{e:"H",x:-2.48,y:0,z:0},{e:"H",x:-1.24,y:-2.15,z:0},{e:"H",x:1.24,y:-2.15,z:0},
            {e:"C",x:1.4,y:2.4,z:0},{e:"O",x:0.8,y:3.4,z:0},{e:"O",x:2.7,y:2.4,z:0},{e:"H",x:3.1,y:3.2,z:0},
            {e:"O",x:2.7,y:0,z:0},{e:"C",x:3.4,y:-1.0,z:0},{e:"O",x:2.9,y:-2.0,z:0},{e:"C",x:4.9,y:-1.0,z:0},
            {e:"H",x:5.3,y:-2.0,z:0},{e:"H",x:5.3,y:-0.4,z:0.88},{e:"H",x:5.3,y:-0.4,z:-0.88}
        ],
        bonds:[
            [0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],
            [2,6,1],[3,7,1],[4,8,1],[5,9,1],
            [1,10,1],[10,11,2],[10,12,1],[12,13,1],
            [0,14,1],[14,15,1],[15,16,2],[15,17,1],[17,18,1],[17,19,1],[17,20,1]
        ]
    },

    // --- ESTERS ---
    "HCOOCH3": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.2,z:0},{e:"O",x:1.1,y:-0.5,z:0},{e:"H",x:-0.9,y:-0.5,z:0},{e:"C",x:2.3,y:0.2,z:0},{e:"H",x:3.1,y:-0.4,z:0},{e:"H",x:2.3,y:0.8,z:0.9},{e:"H",x:2.3,y:0.8,z:-0.9}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[2,4,1],[4,5,1],[4,6,1],[4,7,1]]
    },
    "CH3COOCH3": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.2,z:0},{e:"O",x:1.1,y:-0.5,z:0},{e:"C",x:-1.3,y:-0.6,z:0},{e:"C",x:2.3,y:0.2,z:0},{e:"H",x:-1.3,y:-1.7,z:0},{e:"H",x:-1.8,y:-0.2,z:0.9},{e:"H",x:-1.8,y:-0.2,z:-0.9},{e:"H",x:3.1,y:-0.4,z:0},{e:"H",x:2.3,y:0.8,z:0.9},{e:"H",x:2.3,y:0.8,z:-0.9}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[3,5,1],[3,6,1],[3,7,1],[2,4,1],[4,8,1],[4,9,1],[4,10,1]]
    },
    "CH3COOC2H5": {
        atoms:[{e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.2,z:0},{e:"O",x:1.1,y:-0.5,z:0},{e:"C",x:-1.3,y:-0.6,z:0},{e:"C",x:2.4,y:0.1,z:0},{e:"C",x:3.6,y:-0.8,z:0},{e:"H",x:-1.3,y:-1.7,z:0},{e:"H",x:-1.8,y:-0.2,z:0.9},{e:"H",x:-1.8,y:-0.2,z:-0.9},{e:"H",x:2.4,y:0.7,z:0.9},{e:"H",x:2.4,y:0.7,z:-0.9},{e:"H",x:3.6,y:-1.4,z:0.9},{e:"H",x:3.6,y:-1.4,z:-0.9},{e:"H",x:4.5,y:-0.2,z:0}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[3,6,1],[3,7,1],[3,8,1],[2,4,1],[4,5,1],[4,9,1],[4,10,1],[5,11,1],[5,12,1],[5,13,1]]
    },
    "isoamyl_acetate": {
        atoms:[{e:"C",x:-3.2,y:0.3,z:0},{e:"O",x:-3.2,y:1.5,z:0},{e:"O",x:-2.1,y:-0.4,z:0},{e:"C",x:-4.5,y:-0.5,z:0},{e:"H",x:-4.5,y:-1.6,z:0},{e:"H",x:-5.0,y:-0.1,z:0.9},{e:"H",x:-5.0,y:-0.1,z:-0.9},{e:"C",x:-0.8,y:-0.1,z:0},{e:"H",x:-0.8,y:1.0,z:0},{e:"H",x:-0.5,y:-0.4,z:0.9},{e:"C",x:0.5,y:-0.8,z:-0.5},{e:"H",x:0.2,y:-1.8,z:-0.5},{e:"H",x:0.5,y:-0.4,z:-1.5},{e:"C",x:1.8,y:-0.1,z:0},{e:"H",x:1.8,y:-0.1,z:1.1},{e:"C",x:1.8,y:1.4,z:0},{e:"H",x:1.3,y:1.8,z:-0.9},{e:"H",x:2.8,y:1.8,z:0},{e:"H",x:1.3,y:1.8,z:0.9},{e:"C",x:3.1,y:-0.7,z:-0.5},{e:"H",x:3.1,y:-1.8,z:-0.5},{e:"H",x:3.6,y:-0.3,z:0.4},{e:"H",x:3.6,y:-0.3,z:-1.4}],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[3,4,1],[3,5,1],[3,6,1],[2,7,1],[7,10,1],[7,8,1],[7,9,1],[10,13,1],[10,11,1],[10,12,1],[13,15,1],[13,19,1],[13,14,1],[15,16,1],[15,17,1],[15,18,1],[19,20,1],[19,21,1],[19,22,1]]
    },

    // --- AMINES & HETEROCYCLICS ---
    "CH3NH2": {
        atoms:[
            {e:"N",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.470,y:0.000,z:0.000},
            {e:"H",x:0.380,y:0.930,z:0.380},
            {e:"H",x:0.380,y:-0.930,z:0.380},
            {e:"H",x:-1.850,y:1.030,z:0.000},
            {e:"H",x:-1.850,y:-0.515,z:0.890},
            {e:"H",x:-1.850,y:-0.515,z:-0.890}
        ],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[1,4,1],[1,5,1],[1,6,1]]
    },
    "C2H5NH2": {
        atoms:[
            {e:"N",x:1.340,y:0.000,z:0.000},
            {e:"C",x:0.000,y:0.730,z:0.000},
            {e:"C",x:-1.220,y:-0.170,z:0.000},
            {e:"H",x:1.640,y:0.450,z:0.870},
            {e:"H",x:1.640,y:0.450,z:-0.870},
            {e:"H",x:0.050,y:1.370,z:0.880},
            {e:"H",x:0.050,y:1.370,z:-0.880},
            {e:"H",x:-1.200,y:-0.810,z:0.880},
            {e:"H",x:-1.200,y:-0.810,z:-0.880},
            {e:"H",x:-2.130,y:0.440,z:0.000}
        ],
        bonds:[[0,1,1],[1,2,1],[0,3,1],[0,4,1],[1,5,1],[1,6,1],[2,7,1],[2,8,1],[2,9,1]]
    },
    "CH3NHCH3": {
        atoms:[
            {e:"N",x:0.000,y:0.000,z:0.000},
            {e:"H",x:0.000,y:1.010,z:-0.360},
            {e:"C",x:1.230,y:-0.500,z:0.600},
            {e:"C",x:-1.230,y:-0.500,z:0.600},
            {e:"H",x:1.230,y:-1.590,z:0.580},
            {e:"H",x:2.090,y:-0.130,z:0.060},
            {e:"H",x:1.280,y:-0.180,z:1.640},
            {e:"H",x:-1.230,y:-1.590,z:0.580},
            {e:"H",x:-2.090,y:-0.130,z:0.060},
            {e:"H",x:-1.280,y:-0.180,z:1.640}
        ],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[2,4,1],[2,5,1],[2,6,1],[3,7,1],[3,8,1],[3,9,1]]
    },
    "(CH3)3N": {
        atoms:[
            {e:"N",x:0.000,y:0.400,z:0.000},
            {e:"C",x:0.000,y:-0.200,z:1.380},
            {e:"C",x:1.196,y:-0.200,z:-0.690},
            {e:"C",x:-1.196,y:-0.200,z:-0.690},
            {e:"H",x:0.000,y:-1.290,z:1.380},
            {e:"H",x:0.890,y:0.130,z:1.920},
            {e:"H",x:-0.890,y:0.130,z:1.920},
            {e:"H",x:1.240,y:-1.290,z:-0.700},
            {e:"H",x:2.090,y:0.130,z:-0.230},
            {e:"H",x:1.230,y:0.130,z:-1.720},
            {e:"H",x:-1.240,y:-1.290,z:-0.700},
            {e:"H",x:-2.090,y:0.130,z:-0.230},
            {e:"H",x:-1.230,y:0.130,z:-1.720}
        ],
        bonds:[[0,1,1],[0,2,1],[0,3,1],[1,4,1],[1,5,1],[1,6,1],[2,7,1],[2,8,1],[2,9,1],[3,10,1],[3,11,1],[3,12,1]]
    },
    "C6H5NH2": {
        atoms:[
            {e:"C",x:1.400,y:0.000,z:0.000},
            {e:"C",x:0.700,y:1.210,z:0.000},
            {e:"C",x:-0.700,y:1.210,z:0.000},
            {e:"C",x:-1.400,y:0.000,z:0.000},
            {e:"C",x:-0.700,y:-1.210,z:0.000},
            {e:"C",x:0.700,y:-1.210,z:0.000},
            {e:"N",x:2.840,y:0.000,z:0.200},
            {e:"H",x:3.280,y:0.820,z:-0.200},
            {e:"H",x:3.280,y:-0.820,z:-0.200},
            {e:"H",x:1.240,y:2.150,z:0.000},
            {e:"H",x:-1.240,y:2.150,z:0.000},
            {e:"H",x:-2.480,y:0.000,z:0.000},
            {e:"H",x:-1.240,y:-2.150,z:0.000},
            {e:"H",x:1.240,y:-2.150,z:0.000}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[0,6,1],[6,7,1],[6,8,1],[1,9,1],[2,10,1],[3,11,1],[4,12,1],[5,13,1]]
    },
    "pyridine": {
        atoms:[
            {e:"N",x:0,y:-1.4,z:0},{e:"C",x:1.21,y:-0.7,z:0},{e:"C",x:1.21,y:0.7,z:0},
            {e:"C",x:0,y:1.4,z:0},{e:"C",x:-1.21,y:0.7,z:0},{e:"C",x:-1.21,y:-0.7,z:0},
            {e:"H",x:2.15,y:-1.24,z:0},{e:"H",x:2.15,y:1.24,z:0},{e:"H",x:0,y:2.48,z:0},
            {e:"H",x:-2.15,y:1.24,z:0},{e:"H",x:-2.15,y:-1.24,z:0}
        ],
        bonds:[[0,1,2],[1,2,1],[2,3,2],[3,4,1],[4,5,2],[5,0,1],[1,6,1],[2,7,1],[3,8,1],[4,9,1],[5,10,1]]
    },
    "urea": {
        atoms:[
            {e:"C",x:0,y:0,z:0},{e:"O",x:0,y:1.2,z:0},{e:"N",x:-1.17,y:-0.67,z:0},{e:"N",x:1.17,y:-0.67,z:0},
            {e:"H",x:-2.04,y:-0.18,z:0},{e:"H",x:-1.17,y:-1.67,z:0},{e:"H",x:2.04,y:-0.18,z:0},{e:"H",x:1.17,y:-1.67,z:0}
        ],
        bonds:[[0,1,2],[0,2,1],[0,3,1],[2,4,1],[2,5,1],[3,6,1],[3,7,1]]
    },

    // --- CARBOHYDRATES ---
    "alpha_glucose": {
        atoms:[{e:"O",x:0.9,y:-0.5,z:-0.5},{e:"C",x:1.1,y:0.7,z:0.2},{e:"C",x:0,y:1.3,z:-0.6},{e:"C",x:-1.1,y:0.7,z:0.2},{e:"C",x:-1.1,y:-0.7,z:-0.4},{e:"C",x:0,y:-1.2,z:0.4},{e:"C",x:-0.1,y:-2.7,z:0.0},{e:"O",x:-0.2,y:-3.3,z:1.3},{e:"O",x:1.3,y:0.8,z:1.6},{e:"O",x:0,y:2.7,z:-0.4},{e:"O",x:-2.3,y:1.3,z:-0.2},{e:"O",x:-2.3,y:-1.1,z:0.2},{e:"H",x:2.0,y:1.0,z:-0.3},{e:"H",x:0,y:1.1,z:-1.7},{e:"H",x:-1.1,y:0.7,z:1.3},{e:"H",x:-1.1,y:-0.7,z:-1.5},{e:"H",x:0,y:-1.0,z:1.5},{e:"H",x:0.8,y:-3.0,z:-0.5},{e:"H",x:-1.0,y:-3.0,z:-0.5},{e:"H",x:2.1,y:0.4,z:1.8},{e:"H",x:0.8,y:3.1,z:-0.1},{e:"H",x:-3.0,y:0.9,z:0.3},{e:"H",x:-2.5,y:-0.4,z:0.8},{e:"H",x:-1.0,y:-3.1,z:1.8}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[5,6,1],[6,7,1],[1,8,1],[2,9,1],[3,10,1],[4,11,1],[1,12,1],[2,13,1],[3,14,1],[4,15,1],[5,16,1],[6,17,1],[6,18,1],[8,19,1],[9,20,1],[10,21,1],[11,22,1],[7,23,1]]
    },
    "beta_glucose": {
        atoms:[{e:"O",x:0.9,y:-0.5,z:-0.5},{e:"C",x:1.1,y:0.7,z:0.2},{e:"C",x:0,y:1.3,z:-0.6},{e:"C",x:-1.1,y:0.7,z:0.2},{e:"C",x:-1.1,y:-0.7,z:-0.4},{e:"C",x:0,y:-1.2,z:0.4},{e:"C",x:-0.1,y:-2.7,z:0.0},{e:"O",x:-0.2,y:-3.3,z:1.3},{e:"O",x:2.3,y:0.9,z:-0.4},{e:"O",x:0,y:2.7,z:-0.4},{e:"O",x:-2.3,y:1.3,z:-0.2},{e:"O",x:-2.3,y:-1.1,z:0.2},{e:"H",x:1.1,y:0.7,z:1.3},{e:"H",x:0,y:1.1,z:-1.7},{e:"H",x:-1.1,y:0.7,z:1.3},{e:"H",x:-1.1,y:-0.7,z:-1.5},{e:"H",x:0,y:-1.0,z:1.5},{e:"H",x:0.8,y:-3.0,z:-0.5},{e:"H",x:-1.0,y:-3.0,z:-0.5},{e:"H",x:3.0,y:0.3,z:0.0},{e:"H",x:0.8,y:3.1,z:-0.1},{e:"H",x:-3.0,y:0.9,z:0.3},{e:"H",x:-2.5,y:-0.4,z:0.8},{e:"H",x:-1.0,y:-3.1,z:1.8}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,5,1],[5,0,1],[5,6,1],[6,7,1],[1,8,1],[2,9,1],[3,10,1],[4,11,1],[1,12,1],[2,13,1],[3,14,1],[4,15,1],[5,16,1],[6,17,1],[6,18,1],[8,19,1],[9,20,1],[10,21,1],[11,22,1],[7,23,1]]
    },
    "alpha_fructose": {
        atoms:[{e:"O",x:0,y:-1.0,z:-0.5},{e:"C",x:1.0,y:0,z:0},{e:"C",x:0.3,y:1.3,z:0.3},{e:"C",x:-0.8,y:1.1,z:-0.4},{e:"C",x:-1.1,y:-0.3,z:0.2},{e:"C",x:2.2,y:-0.5,z:0.6},{e:"O",x:3.2,y:0.4,z:0.8},{e:"C",x:-2.4,y:-0.8,z:-0.4},{e:"O",x:-3.4,y:-0.2,z:0.3},{e:"O",x:1.4,y:0.3,z:-1.4},{e:"O",x:0.6,y:2.5,z:-0.4},{e:"O",x:-1.5,y:1.8,z:0.5},{e:"H",x:0.2,y:1.3,z:1.4},{e:"H",x:-0.6,y:1.1,z:-1.5},{e:"H",x:-1.2,y:-0.3,z:1.3},{e:"H",x:1.9,y:-0.9,z:1.6},{e:"H",x:2.5,y:-1.3,z:0.0},{e:"H",x:-2.3,y:-1.9,z:-0.3},{e:"H",x:-2.7,y:-0.6,z:-1.4},{e:"H",x:3.8,y:0.1,z:0.1},{e:"H",x:2.3,y:0.6,z:-1.5},{e:"H",x:1.5,y:2.5,z:-0.7},{e:"H",x:-1.1,y:2.7,z:0.3},{e:"H",x:-3.1,y:-0.3,z:1.2}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,0,1],[1,5,1],[5,6,1],[4,7,1],[7,8,1],[1,9,1],[2,10,1],[3,11,1],[2,12,1],[3,13,1],[4,14,1],[5,15,1],[5,16,1],[7,17,1],[7,18,1],[6,19,1],[9,20,1],[10,21,1],[11,22,1],[8,23,1]]
    },
    "beta_fructose": {
        atoms:[{e:"O",x:0,y:-1.0,z:-0.5},{e:"C",x:1.0,y:0,z:0},{e:"C",x:0.3,y:1.3,z:0.3},{e:"C",x:-0.8,y:1.1,z:-0.4},{e:"C",x:-1.1,y:-0.3,z:0.2},{e:"C",x:2.2,y:-0.5,z:-0.6},{e:"O",x:3.2,y:0.4,z:-0.8},{e:"C",x:-2.4,y:-0.8,z:-0.4},{e:"O",x:-3.4,y:-0.2,z:0.3},{e:"O",x:1.4,y:0.3,z:1.4},{e:"O",x:0.6,y:2.5,z:-0.4},{e:"O",x:-1.5,y:1.8,z:0.5},{e:"H",x:0.2,y:1.3,z:1.4},{e:"H",x:-0.6,y:1.1,z:-1.5},{e:"H",x:-1.2,y:-0.3,z:1.3},{e:"H",x:1.9,y:-0.9,z:-1.6},{e:"H",x:2.5,y:-1.3,z:0.0},{e:"H",x:-2.3,y:-1.9,z:-0.3},{e:"H",x:-2.7,y:-0.6,z:-1.4},{e:"H",x:3.8,y:0.1,z:-0.1},{e:"H",x:2.3,y:0.6,z:1.2},{e:"H",x:1.5,y:2.5,z:-0.7},{e:"H",x:-1.1,y:2.8,z:0.3},{e:"H",x:-3.1,y:-0.3,z:1.2}],
        bonds:[[0,1,1],[1,2,1],[2,3,1],[3,4,1],[4,0,1],[1,5,1],[5,6,1],[4,7,1],[7,8,1],[1,9,1],[2,10,1],[3,11,1],[2,12,1],[3,13,1],[4,14,1],[5,15,1],[5,16,1],[7,17,1],[7,18,1],[6,19,1],[9,20,1],[10,21,1],[11,22,1],[8,23,1]]
    },

    // Khởi tạo phím rỗng cho các đường đôi, chúng sẽ được sinh ra ở initComplexMolecules()
    "saccharose": { atoms: [], bonds: [] }, 
    "maltose": { atoms: [], bonds: [] },

    // --- AMINO ACIDS ---
    "Gly": {
        atoms:[
            {e:"N",x:1.201,y:0.847,z:0.000},
            {e:"C",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.250,y:0.810,z:0.000},
            {e:"O",x:-1.220,y:2.040,z:0.000},
            {e:"O",x:-2.390,y:0.050,z:0.000},
            {e:"H",x:-3.230,y:0.540,z:0.000},
            {e:"H",x:0.080,y:-0.630,z:0.890},
            {e:"H",x:0.080,y:-0.630,z:-0.890},
            {e:"H",x:1.180,y:1.450,z:0.820},
            {e:"H",x:1.180,y:1.450,z:-0.820}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,2],[2,4,1],[4,5,1],[1,6,1],[1,7,1],[0,8,1],[0,9,1]]
    },
    "Ala": {
        atoms:[
            {e:"N",x:1.201,y:0.847,z:0.000},
            {e:"C",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.250,y:0.810,z:0.000},
            {e:"O",x:-1.220,y:2.040,z:0.000},
            {e:"O",x:-2.390,y:0.050,z:0.000},
            {e:"H",x:-3.230,y:0.540,z:0.000},
            {e:"H",x:0.100,y:-0.560,z:0.930},
            {e:"C",x:0.140,y:-0.820,z:-1.270},
            {e:"H",x:-0.800,y:-1.350,z:-1.450},
            {e:"H",x:0.950,y:-1.550,z:-1.190},
            {e:"H",x:0.380,y:-0.170,z:-2.120},
            {e:"H",x:1.180,y:1.450,z:0.820},
            {e:"H",x:1.180,y:1.450,z:-0.820}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,2],[2,4,1],[4,5,1],[1,6,1],[1,7,1],[7,8,1],[7,9,1],[7,10,1],[0,11,1],[0,12,1]]
    },
    "Val": {
        atoms:[
            {e:"N",x:1.201,y:0.847,z:0.000},
            {e:"C",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.250,y:0.810,z:0.000},
            {e:"O",x:-1.220,y:2.040,z:0.000},
            {e:"O",x:-2.390,y:0.050,z:0.000},
            {e:"H",x:-3.230,y:0.540,z:0.000},
            {e:"H",x:0.100,y:-0.560,z:0.930},
            {e:"C",x:0.130,y:-0.840,z:-1.270},
            {e:"H",x:1.100,y:-1.350,z:-1.330},
            {e:"C",x:-0.980,y:-1.880,z:-1.280},
            {e:"H",x:-0.760,y:-2.640,z:-0.530},
            {e:"H",x:-1.940,y:-1.380,z:-1.100},
            {e:"H",x:-1.030,y:-2.380,z:-2.250},
            {e:"C",x:0.190,y:-0.100,z:-2.590},
            {e:"H",x:1.150,y:0.420,z:-2.640},
            {e:"H",x:-0.620,y:0.630,z:-2.700},
            {e:"H",x:0.110,y:-0.770,z:-3.440},
            {e:"H",x:1.180,y:1.450,z:0.820},
            {e:"H",x:1.180,y:1.450,z:-0.820}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,2],[2,4,1],[4,5,1],[1,6,1],[1,7,1],[7,8,1],[7,9,1],[7,13,1],[9,10,1],[9,11,1],[9,12,1],[13,14,1],[13,15,1],[13,16,1],[0,17,1],[0,18,1]]
    },
    "Glu": {
        atoms:[
            {e:"N",x:1.201,y:0.847,z:0.000},
            {e:"C",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.250,y:0.810,z:0.000},
            {e:"O",x:-1.220,y:2.040,z:0.000},
            {e:"O",x:-2.390,y:0.050,z:0.000},
            {e:"H",x:-3.230,y:0.540,z:0.000},
            {e:"H",x:0.100,y:-0.560,z:0.930},
            {e:"C",x:0.140,y:-0.820,z:-1.270},
            {e:"H",x:1.100,y:-1.320,z:-1.350},
            {e:"H",x:0.060,y:-0.190,z:-2.160},
            {e:"C",x:-0.930,y:-1.930,z:-1.300},
            {e:"H",x:-1.900,y:-1.440,z:-1.200},
            {e:"H",x:-0.830,y:-2.570,z:-0.420},
            {e:"C",x:-0.830,y:-2.740,z:-2.590},
            {e:"O",x:0.200,y:-2.850,z:-3.270},
            {e:"O",x:-1.920,y:-3.350,z:-2.850},
            {e:"H",x:-1.830,y:-3.950,z:-3.590},
            {e:"H",x:1.180,y:1.450,z:0.820},
            {e:"H",x:1.180,y:1.450,z:-0.820}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,2],[2,4,1],[4,5,1],[1,6,1],[1,7,1],[7,8,1],[7,9,1],[7,10,1],[10,11,1],[10,12,1],[10,13,1],[13,14,2],[13,15,1],[15,16,1],[0,17,1],[0,18,1]]
    },
    "Lys": {
        atoms:[
            {e:"N",x:1.201,y:0.847,z:0.000},
            {e:"C",x:0.000,y:0.000,z:0.000},
            {e:"C",x:-1.250,y:0.810,z:0.000},
            {e:"O",x:-1.220,y:2.040,z:0.000},
            {e:"O",x:-2.390,y:0.050,z:0.000},
            {e:"H",x:-3.230,y:0.540,z:0.000},
            {e:"H",x:0.100,y:-0.560,z:0.930},
            {e:"C",x:0.140,y:-0.820,z:-1.270},
            {e:"H",x:1.100,y:-1.320,z:-1.350},
            {e:"H",x:0.060,y:-0.190,z:-2.160},
            {e:"C",x:-0.930,y:-1.930,z:-1.300},
            {e:"H",x:-1.900,y:-1.430,z:-1.200},
            {e:"H",x:-0.840,y:-2.570,z:-0.420},
            {e:"C",x:-0.830,y:-2.760,z:-2.570},
            {e:"H",x:0.140,y:-3.270,z:-2.620},
            {e:"H",x:-1.070,y:-2.130,z:-3.430},
            {e:"C",x:-1.900,y:-3.840,z:-2.600},
            {e:"H",x:-2.880,y:-3.340,z:-2.530},
            {e:"H",x:-1.790,y:-4.480,z:-1.720},
            {e:"N",x:-1.820,y:-4.620,z:-3.840},
            {e:"H",x:-0.880,y:-4.420,z:-4.240},
            {e:"H",x:-2.540,y:-4.280,z:-4.490},
            {e:"H",x:1.180,y:1.450,z:0.820},
            {e:"H",x:1.180,y:1.450,z:-0.820}
        ],
        bonds:[[0,1,1],[1,2,1],[2,3,2],[2,4,1],[4,5,1],[1,6,1],[1,7,1],[7,8,1],[7,9,1],[7,10,1],[10,11,1],[10,12,1],[10,13,1],[13,14,1],[13,15,1],[13,16,1],[16,17,1],[16,18,1],[16,19,1],[19,20,1],[19,21,1],[0,22,1],[0,23,1]]
    }
};

// =====================================================================
// P5.JS CORE & INIT (ĐÃ SỬA THUẬT TOÁN ĐỂ BẢO TOÀN sp3 100%)
// =====================================================================
function preload() {
    myFont = loadFont('https://cdnjs.cloudflare.com/ajax/libs/topcoat/0.8.0/font/SourceCodePro-Bold.otf');
}

// Tổng hợp Carbohydrates phức tạp bằng thuật toán dịch điểm hoàn hảo
function initComplexMolecules() {
    if (!MOLECULE_DATA["alpha_glucose"] || !MOLECULE_DATA["beta_fructose"]) return;
    
    let glc = MOLECULE_DATA["alpha_glucose"];
    let fru = MOLECULE_DATA["beta_fructose"];

    const centerMolecule = (atoms) => {
        let cx = 0, cy = 0, cz = 0;
        for (let a of atoms) { cx += a.x; cy += a.y; cz += a.z; }
        cx /= atoms.length; cy /= atoms.length; cz /= atoms.length;
        for (let a of atoms) { a.x -= cx; a.y -= cy; a.z -= cz; }
    };
    
    // --- MALTOSE --- (alpha-D-Glcp-(1->4)-D-Glcp)
    // Thuật toán giữ lại O1 của phân tử 1 làm cầu nối. 
    // Dịch toàn bộ phân tử 2 sao cho điểm O4 cũ của nó trùng khít vào O1 của phân tử 1.
    // Điều này giúp liên kết C4 mới tạo ra cùng hướng với liên kết C4-O4 cũ => giữ nguyên vẹn sp3.
    let m_atoms = [], m_bonds = [], m_map1 = {}, m_map2 = {};
    
    // Nạp Glucose 1 (bỏ H của O1)
    for(let i=0; i<glc.atoms.length; i++) {
        if(i===19) continue; 
        m_map1[i] = m_atoms.length;
        m_atoms.push({...glc.atoms[i]});
    }
    for(let b of glc.bonds) {
        if(b[0]===19 || b[1]===19) continue;
        m_bonds.push([m_map1[b[0]], m_map1[b[1]], b[2]||1]);
    }
    
    // Lấy tọa độ O1 của Glc1 và O4 của Glc2 để tịnh tiến
    let o1_glc1 = glc.atoms[8];
    let o4_glc2 = glc.atoms[10];
    let m_dx = o1_glc1.x - o4_glc2.x;
    let m_dy = o1_glc1.y - o4_glc2.y;
    let m_dz = o1_glc1.z - o4_glc2.z;

    // Nạp Glucose 2 (Bỏ đi O4 và H-O4)
    for(let i=0; i<glc.atoms.length; i++) {
        if(i===10 || i===21) continue;
        m_map2[i] = m_atoms.length;
        let a = glc.atoms[i];
        // Cộng thêm tọa độ tịnh tiến
        m_atoms.push({e: a.e, x: a.x + m_dx, y: a.y + m_dy, z: a.z + m_dz});
    }
    for(let b of glc.bonds) {
        if(b[0]===10 || b[1]===10 || b[0]===21 || b[1]===21) continue;
        m_bonds.push([m_map2[b[0]], m_map2[b[1]], b[2]||1]);
    }
    
    // Nối C4 của Glucose 2 vào cầu nối O1 của Glucose 1
    m_bonds.push([m_map2[3], m_map1[8], 1]);
    centerMolecule(m_atoms);
    MOLECULE_DATA["maltose"] = { atoms: m_atoms, bonds: m_bonds };

    // --- SACCHAROSE --- (alpha-D-Glcp-(1->2)-beta-D-Fruf)
    // Tương tự, tịnh tiến vòng Fructose sao cho O2 của nó khớp hoàn hảo vào O1 của Glucose.
    // Trước khi tịnh tiến, lật trục Y cho Fructose xoay ra hướng ngoài để không đè vào vòng Glucose.
    let s_atoms = [], s_bonds = [], s_map1 = {}, s_map2 = {};
    
    // Nạp Glucose (Bỏ H của O1)
    for(let i=0; i<glc.atoms.length; i++) {
        if(i===19) continue;
        s_map1[i] = s_atoms.length;
        s_atoms.push({...glc.atoms[i]});
    }
    for(let b of glc.bonds) {
        if(b[0]===19 || b[1]===19) continue;
        s_bonds.push([s_map1[b[0]], s_map1[b[1]], b[2]||1]);
    }
    
    // Lật trục Y cho Fructose (xoay 180 độ)
    let fru_rot = fru.atoms.map(a => ({e: a.e, x: -a.x, y: a.y, z: -a.z}));
    
    // Tính khoảng dịch chuyển O2 -> O1
    let o1_glc_suc = glc.atoms[8];
    let o2_fru_rot = fru_rot[9]; 
    let s_dx = o1_glc_suc.x - o2_fru_rot.x;
    let s_dy = o1_glc_suc.y - o2_fru_rot.y;
    let s_dz = o1_glc_suc.z - o2_fru_rot.z;

    // Nạp Fructose (Bỏ đi O2 và H-O2)
    for(let i=0; i<fru_rot.length; i++) {
        if(i===9 || i===20) continue;
        s_map2[i] = s_atoms.length;
        let a = fru_rot[i];
        s_atoms.push({e: a.e, x: a.x + s_dx, y: a.y + s_dy, z: a.z + s_dz});
    }
    for(let b of fru.bonds) {
        if(b[0]===9 || b[1]===9 || b[0]===20 || b[1]===20) continue;
        s_bonds.push([s_map2[b[0]], s_map2[b[1]], b[2]||1]);
    }
    
    // Nối C2 của Fructose (index 1) vào cầu O1 của Glucose (index 8)
    s_bonds.push([s_map2[1], s_map1[8], 1]);
    centerMolecule(s_atoms);
    MOLECULE_DATA["saccharose"] = { atoms: s_atoms, bonds: s_bonds };
}

function setup() {
    initComplexMolecules();

    const container = document.getElementById('canvas-container');
    const canvas = createCanvas(container.offsetWidth, container.offsetHeight, WEBGL);
    canvas.parent('canvas-container');
    document.oncontextmenu = () => false;
    pixelDensity(window.devicePixelRatio > 1 ? 1.5 : 1);
    textFont(myFont); textSize(16); textAlign(CENTER, CENTER);

    document.getElementById('molecule-select').addEventListener('change', function () {
        loadMolecule(this.value); this.classList.add('has-value');
        if (window.innerWidth <= 768) toggleMenu(false);
    });
    document.getElementById('toggle-rotate').addEventListener('click', function () {
        isRotating = !isRotating; updateButtonsText(); this.classList.toggle('active');
    });
    document.getElementById('toggle-labels').addEventListener('click', function () {
        showLabels = !showLabels; updateButtonsText(); this.classList.toggle('active');
    });
    document.getElementById('language-select').addEventListener('change', function () {
        setLanguage(this.value);
    });
    document.getElementById('btn-save-image').addEventListener('click', captureImageDesktop);
    document.getElementById('mobile-menu-btn').addEventListener('click', () => toggleMenu(true));
    document.getElementById('close-menu-btn').addEventListener('click', () => toggleMenu(false));
    document.getElementById('menu-overlay').addEventListener('click', () => toggleMenu(false));

    const popup = document.getElementById('save-popup-overlay');
    document.getElementById('quick-snap-btn').addEventListener('click', () => {
        popup.classList.remove('hidden');
        isRotating = false;
        document.getElementById('toggle-rotate').classList.remove('active');
    });
    document.getElementById('mobile-cancel-btn').addEventListener('click', () => {
        popup.classList.add('hidden');
        isRotating = true;
        document.getElementById('toggle-rotate').classList.add('active');
    });
    document.getElementById('mobile-save-btn').addEventListener('click', () => {
        captureImageMobile();
        popup.classList.add('hidden');
    });
    setTimeout(windowResized, 100);
    setLanguage('vi');
}

function toggleMenu(show) {
    const ui = document.getElementById('ui-container');
    const ov = document.getElementById('menu-overlay');
    if (show) { ui.classList.add('open'); ov.classList.add('active'); }
    else { ui.classList.remove('open'); ov.classList.remove('active'); }
}

function touchStarted() {
    if (touches.length === 1) {
        isDragging = true; lastX = touches[0].x; lastY = touches[0].y;
    } else if (touches.length === 2) {
        isDragging = false;
        let dx = touches[1].x - touches[0].x, dy = touches[1].y - touches[0].y;
        initialDist = Math.sqrt(dx*dx + dy*dy);
        initialZoom = zoom; initialPanX = panX; initialPanY = panY;
        lastX = (touches[0].x + touches[1].x) / 2;
        lastY = (touches[0].y + touches[1].y) / 2;
    }
}

function touchMoved() {
    if (mouseX < 0 || mouseX > width || mouseY < 0 || mouseY > height) return true;
    if (touches.length === 1 && isDragging) {
        rotY += (touches[0].x - lastX) * 0.015;
        rotX += (touches[0].y - lastY) * 0.015;
        lastX = touches[0].x; lastY = touches[0].y;
    } else if (touches.length === 2) {
        let dx = touches[1].x - touches[0].x, dy = touches[1].y - touches[0].y;
        let d = Math.sqrt(dx*dx + dy*dy);
        if (initialDist > 0) zoom = constrain(initialZoom * (d / initialDist), 0.1, 5);
        let cx = (touches[0].x + touches[1].x) / 2;
        let cy = (touches[0].y + touches[1].y) / 2;
        panX = initialPanX + (cx - lastX);
        panY = initialPanY + (cy - lastY);
    }
    return false;
}

function mousePressed() {
    if (mouseX > 0 && mouseX < width && mouseY > 0 && mouseY < height) {
        isDragging = true; lastX = mouseX; lastY = mouseY;
    }
}
function mouseReleased() { isDragging = false; }
function mouseDragged() {
    if (isDragging && touches.length === 0) {
        let dx = mouseX - lastX, dy = mouseY - lastY;
        if (mouseButton === LEFT) { rotY += dx * 0.01; rotX += dy * 0.01; }
        else if (mouseButton === RIGHT) { panX += dx; panY += dy; }
        lastX = mouseX; lastY = mouseY;
    }
}
function mouseWheel(event) {
    if (mouseX > 0 && mouseX < width && mouseY > 0 && mouseY < height) {
        zoom = constrain(zoom + event.delta * -0.001, 0.1, 5);
        return false;
    }
    return true;
}

// =====================================================================
// RENDER
// =====================================================================
function renderScene(pg, w, h, sFactor = 1, isSnapshot = false) {
    pg.clear();
    if (document.getElementById('snap-format').value === 'jpg' || sFactor === 1) pg.background(0);
    if (isSnapshot) {
        const fov = PI / 6, camZ = (h / 2.0) / Math.tan(fov / 2.0);
        pg.camera(0, 0, camZ, 0, 0, 0, 0, 1, 0);
        pg.perspective(fov, w / h, 10, 500000);
    }
    pg.noStroke();
    pg.ambientLight(100);
    pg.directionalLight(180, 180, 180, 0.5, 1, -1);
    pg.pointLight(100, 100, 100, 0, 0, 500);
    pg.push();
    pg.translate(panX * sFactor, panY * sFactor, 0);
    pg.scale(zoom * sFactor);
    pg.rotateX(rotX);
    pg.rotateY(rotY);
    pg.rotateY(autoRotationAngle);

    if (!currentMoleculeKey) {
        pg.push();
        pg.rotateY(-(rotY + autoRotationAngle)); pg.rotateX(-rotX);
        pg.scale(1 / (zoom * sFactor));
        if (sFactor === 1) {
            let gl = pg._renderer.GL;
            gl.disable(gl.DEPTH_TEST);
            pg.textSize(14); pg.fill(150);
            pg.text(TRANSLATIONS[currentLang].canvasMsg, 0, 0);
            gl.enable(gl.DEPTH_TEST);
        }
        pg.pop(); pg.pop(); return;
    }

    for (let b of bonds) {
        let a1 = atoms[b[0]], a2 = atoms[b[1]], order = b[2] || 1;
        drawBondMulti(pg,
            createVector(a1.x * SCALE, a1.y * SCALE, a1.z * SCALE),
            createVector(a2.x * SCALE, a2.y * SCALE, a2.z * SCALE),
            order);
    }

    if (SINGLE_RING_AROMATIC.includes(currentMoleculeKey)) {
        drawAromaticRing(pg, 0, 0);
    } else if (DOUBLE_RING_AROMATIC.includes(currentMoleculeKey)) {
        drawAromaticRing(pg,  1.21 * SCALE, 0);
        drawAromaticRing(pg, -1.21 * SCALE, 0);
    }

    for (let atom of atoms) {
        let x = atom.x * SCALE, y = atom.y * SCALE, z = atom.z * SCALE;
        let ei = ELEMENTS[atom.e] || { color:[200,200,200], radius:30, textColor:[0,0,0] };
        pg.push();
        pg.translate(x, y, z);
        pg.fill(ei.color); pg.ambientMaterial(ei.color);
        pg.specularMaterial(60); pg.shininess(20);
        let detail = isSnapshot ? 80 : (window.innerWidth < 768 ? 24 : 40);
        pg.sphere(ei.radius, detail, detail);
        if (showLabels) {
            pg.rotateY(-(rotY + autoRotationAngle)); pg.rotateX(-rotX);
            pg.translate(0, 0, ei.radius + 2);
            pg.fill(ei.textColor); pg.noLights();
            pg.scale(1 / (zoom * sFactor));
            pg.textSize(16 * zoom * sFactor);
            pg.textAlign(CENTER, CENTER);
            pg.text(atom.e, 0, 0);
        }
        pg.pop();
    }
    pg.pop();
}

function windowResized() {
    const c = document.getElementById('canvas-container');
    if (c && c.offsetWidth > 0) resizeCanvas(c.offsetWidth, c.offsetHeight);
}

function setLanguage(lang) {
    currentLang = lang;
    const t = TRANSLATIONS[lang];
    const s = (id, v) => { let e = document.getElementById(id); if (e) e.innerText = v; };
    s('header-title', t.headerTitle); s('header-sub', t.headerSub);
    const ms = document.getElementById('molecule-select');
    if (ms && ms.options.length > 0) ms.options[0].innerText = t.placeholder;
    updateButtonsText();
    s('btn-save-image', t.btnSave);
    let ro = document.querySelector('#snap-res option[value="current"]'); if (ro) ro.innerText = t.resCurrent;
    let po = document.querySelector('#snap-format option[value="png"]');  if (po) po.innerText = t.fmtPNG;
    let jo = document.querySelector('#snap-format option[value="jpg"]');  if (jo) jo.innerText = t.fmtJPG;
    
    for (const [id, label] of Object.entries(t.optgroups)) {
        const el = document.getElementById(id); if (el) el.label = label;
    }
}

function updateButtonsText() {
    const t = TRANSLATIONS[currentLang];
    let br = document.getElementById('toggle-rotate'); if (br) br.innerText = t.btnRotate;
    let bl = document.getElementById('toggle-labels'); if (bl) bl.innerText = t.btnLabels;
}

function calculateOptimalZoom(currentAtoms) {
    if (!currentAtoms || currentAtoms.length === 0) return 1.0;
    let minX=Infinity, maxX=-Infinity, minY=Infinity, maxY=-Infinity;
    for (let a of currentAtoms) {
        if (a.x < minX) minX = a.x; if (a.x > maxX) maxX = a.x;
        if (a.y < minY) minY = a.y; if (a.y > maxY) maxY = a.y;
    }
    if (minX === Infinity) return 1.5;
    let cw = (maxX - minX + 1.2) * SCALE;
    let ch = (maxY - minY + 1.2) * SCALE;
    return constrain(Math.min((width * 0.55) / cw, (height * 0.55) / ch), 0.3, 2.5);
}

function loadMolecule(type) {
    currentMoleculeKey = type;
    const data = MOLECULE_DATA[type];
    if (data) {
        atoms = JSON.parse(JSON.stringify(data.atoms));
        bonds = data.bonds;
        autoRotationAngle = 0; rotX = 0; rotY = 0; panX = 0; panY = 0;
        zoom = calculateOptimalZoom(atoms);
        if (window.innerWidth < 768) zoom *= 0.8;
    }
}

function captureImageDesktop() {
    performCapture(
        document.getElementById('snap-res').value,
        document.getElementById('snap-format').value
    );
}
function captureImageMobile() {
    performCapture(
        document.getElementById('mobile-snap-res').value,
        document.getElementById('mobile-snap-format').value
    );
}

function performCapture(resValue, formatValue) {
    const molName = currentMoleculeKey || 'molecule';
    const ts = new Date().toISOString().replace(/[-:.]/g, "");
    const filename = `${molName}_${ts}`;
    const isMobile = window.innerWidth <= 768;
    if (resValue === "current") {
        if (!isMobile) {
            saveCanvas(filename, formatValue);
        } else {
            const cv = document.getElementById('defaultCanvas0');
            if (cv) cv.toBlob(
                b => showMobileSaveModal(b, filename, formatValue),
                `image/${formatValue === 'jpg' ? 'jpeg' : 'png'}`
            );
        }
    } else {
        const dims = resValue.split('x');
        let targetW = parseInt(dims[0]), targetH = parseInt(dims[1]);
        let pg = createGraphics(targetW, targetH, WEBGL);
        pg.pixelDensity(1); pg.textFont(myFont);
        renderScene(pg, targetW, targetH, targetH / height, true);
        if (!isMobile) {
            save(pg, filename + '.' + formatValue); pg.remove();
        } else {
            pg.canvas.toBlob(b => {
                showMobileSaveModal(b, filename, formatValue); pg.remove();
            }, `image/${formatValue === 'jpg' ? 'jpeg' : 'png'}`);
        }
    }
}

function showMobileSaveModal(blob, filename, ext) {
    const imageUrl = URL.createObjectURL(blob);
    const modal = document.createElement('div');
    modal.style.cssText = 'position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,0.95);z-index:9999;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:20px;touch-action:auto;';

    const img = document.createElement('img');
    img.src = imageUrl;
    img.style.cssText = 'max-width:100%;max-height:65%;border:2px solid #555;border-radius:8px;margin-bottom:15px;pointer-events:auto;';

    const ac = document.createElement('div');
    ac.style.cssText = 'display:flex;gap:10px;flex-direction:column;width:100%;max-width:300px;';

    const mkBtn = (txt, bg, fn) => {
        const b = document.createElement('button');
        b.innerText = txt;
        b.style.cssText = `padding:12px;background:${bg};color:white;border:none;border-radius:8px;font-size:15px;font-weight:bold;cursor:pointer;`;
        b.onclick = fn;
        return b;
    };

    if (navigator.canShare) {
        ac.appendChild(mkBtn('Chia sẻ / Lưu Ảnh (Khuyên dùng)', '#3794ff', async () => {
            try {
                const file = new File([blob], `${filename}.${ext}`, { type: blob.type });
                if (navigator.canShare({ files: [file] })) {
                    await navigator.share({
                        files: [file],
                        title: 'Cấu trúc phân tử',
                        text: `Phân tử ${filename}`
                    });
                } else {
                    alert("Trình duyệt không hỗ trợ chia sẻ file. Dùng nút Tải xuống.");
                }
            } catch (e) { console.log(e); }
        }));
    }

    ac.appendChild(mkBtn('Tải xuống Tệp (Files)', '#28a745', () => {
        const a = document.createElement('a');
        a.href = imageUrl; a.download = `${filename}.${ext}`;
        document.body.appendChild(a); a.click(); document.body.removeChild(a);
        alert("Đã bắt đầu tải xuống. Kiểm tra thư mục Downloads.");
    }));

    ac.appendChild(mkBtn('Đóng', '#444', () => {
        document.body.removeChild(modal);
        URL.revokeObjectURL(imageUrl);
    }));

    modal.appendChild(img);
    modal.appendChild(ac);
    document.body.appendChild(modal);
}

// =====================================================================
// DRAWING HELPERS
// =====================================================================
function drawAromaticRing(pg, offsetX, offsetY) {
    const radius = 0.9 * SCALE;
    const dashCount = 8, gapRatio = 0.2;
    const segAngle = TWO_PI / dashCount;
    const drawAngle = segAngle * (1 - gapRatio);
    const stepsPerDash = 6, tubeR = 2.5;
    pg.fill(150); pg.specularMaterial(50); pg.noStroke();
    for (let i = 0; i < dashCount; i++) {
        let st = i * segAngle;
        for (let j = 0; j < stepsPerDash; j++) {
            let t1 = st + (drawAngle * j / stepsPerDash);
            let t2 = st + (drawAngle * (j + 1) / stepsPerDash);
            drawCylinderBetweenPoints(pg,
                createVector(cos(t1)*radius + offsetX, sin(t1)*radius + offsetY, 0),
                createVector(cos(t2)*radius + offsetX, sin(t2)*radius + offsetY, 0),
                tubeR);
        }
    }
}

function drawCylinderBetweenPoints(pg, p1, p2, r) {
    let v = p5.Vector.sub(p2, p1);
    let len = v.mag();
    if (len < 0.001) return;
    pg.push();
    pg.translate((p1.x+p2.x)/2, (p1.y+p2.y)/2, (p1.z+p2.z)/2);
    let axis = createVector(0, 1, 0).cross(v);
    let angle = acos(constrain(createVector(0,1,0).dot(v.copy().normalize()), -1, 1));
    if (axis.mag() > 0.001) pg.rotate(angle, axis);
    else if (v.y < 0) pg.rotateX(PI);
    pg.cylinder(r, len, 6, 1);
    pg.pop();
}

function drawBondMulti(pg, p1, p2, order) {
    let dist = p1.dist(p2);
    if (dist < 0.1) return;
    pg.push();
    pg.translate((p1.x+p2.x)/2, (p1.y+p2.y)/2, (p1.z+p2.z)/2);
    let v = p5.Vector.sub(p2, p1).normalize();
    let yAxis = createVector(0, 1, 0);
    let axis = yAxis.cross(v);
    let angle = acos(constrain(yAxis.dot(v), -1, 1));
    if (axis.mag() > 0.001) pg.rotate(angle, axis);
    else if (v.y < 0) pg.rotateX(PI);
    pg.fill(150); pg.specularMaterial(30);
    let bondR = 5, gap = 12;
    let detail = (window.innerWidth < 768) ? 12 : 24;
    if (order === 1) {
        pg.cylinder(bondR, dist, detail, 1);
    } else if (order === 2) {
        pg.push(); pg.translate(gap/2, 0, 0); pg.cylinder(bondR, dist, detail, 1); pg.pop();
        pg.push(); pg.translate(-gap/2, 0, 0); pg.cylinder(bondR, dist, detail, 1); pg.pop();
    } else if (order === 3) {
        pg.cylinder(bondR, dist, detail, 1);
        pg.push(); pg.translate(gap, 0, 0); pg.cylinder(bondR, dist, detail, 1); pg.pop();
        pg.push(); pg.translate(-gap, 0, 0); pg.cylinder(bondR, dist, detail, 1); pg.pop();
    }
    pg.pop();
}

function draw() {
    if (isRotating) autoRotationAngle += 0.01;
    renderScene(this, width, height, 1);
}