:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #141414;
    --bg-tertiary: #1f1f1f;
    --text-primary: #e5e5e5;
    --text-secondary: #a3a3a3;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --border: #262626;
    --success: #10b981;
    --error: #ef4444;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background: var(--bg-primary);
    font-family: 'Inter', sans-serif;
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(20, 20, 20, 0.95);
}

.logo {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: 1rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: all 0.2s;
    font-size: 0.95rem;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
    background: var(--bg-tertiary);
}

#app {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1.5rem;
}

/* Upload Page */
.upload-container {
    max-width: 600px;
    margin: 2rem auto;
}

.upload-area {
    background: var(--bg-secondary);
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    margin-bottom: 1.5rem;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--accent);
    background: var(--bg-tertiary);
}

.upload-icon {
    width: 48px;
    height: 48px;
    stroke: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-title {
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.upload-subtitle {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.selected-file {
    background: var(--bg-secondary);
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 1rem;
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--text-primary);
}

.file-icon {
    width: 20px;
    height: 20px;
    stroke: var(--text-secondary);
}

.file-name {
    font-weight: 500;
}

.file-size {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.btn {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    font-family: 'Inter', sans-serif;
}

.btn-primary {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
}

.btn-primary:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
}

.btn:active {
    transform: translateY(1px);
}

.button-group {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
}

/* Files Grid */
.files-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 2rem;
}

.files-title {
    font-size: 1.5rem;
    font-weight: 600;
}

.files-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
}

.file-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.25rem;
    transition: all 0.2s;
}

.file-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.file-card-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.file-card-icon {
    width: 24px;
    height: 24px;
    stroke: var(--text-secondary);
}

.file-card-name {
    font-weight: 500;
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-card-meta {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.file-meta-item {
    display: flex;
    justify-content: space-between;
}

.file-meta-label {
    color: var(--text-secondary);
}

.file-meta-value {
    color: var(--text-primary);
}

.file-card-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
    flex: 1;
    text-align: center;
    text-decoration: none;
    color: var(--text-primary);
}

/* Download Page */
.download-container {
    max-width: 500px;
    margin: 3rem auto;
    text-align: center;
}

.download-icon {
    width: 64px;
    height: 64px;
    stroke: var(--accent);
    margin-bottom: 1.5rem;
}

.download-title {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.download-meta {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.5rem;
    margin: 2rem 0;
    text-align: left;
}

.meta-row {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border);
}

.meta-row:last-child {
    border-bottom: none;
}

.meta-label {
    color: var(--text-secondary);
}

.meta-value {
    color: var(--text-primary);
    font-weight: 500;
}

.download-btn {
    display: inline-block;
    width: 100%;
    padding: 1rem;
    background: var(--accent);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: all 0.2s;
}

.download-btn:hover {
    background: var(--accent-hover);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(4px);
    z-index: 1000;
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    min-width: 320px;
    border: 1px solid var(--border);
}

.modal h3 {
    margin-bottom: 1.5rem;
    text-align: center;
}

.progress-container {
    width: 100%;
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 1rem;
}

.progress-bar {
    height: 100%;
    background: var(--accent);
    width: 0%;
    transition: width 0.3s;
}

.progress-text {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding: 1rem 1.5rem;
    border-radius: 8px;
    border: 1px solid var(--border);
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s;
    z-index: 1000;
    max-width: 350px;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

.toast.success {
    border-color: var(--success);
}

.toast.error {
    border-color: var(--error);
}

/* Loading */
.loading {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    border-radius: 8px;
    border: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 640px) {
    header {
        padding: 1rem;
    }
    
    #app {
        padding: 0 1rem;
    }
    
    .files-grid {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        width: 90%;
        min-width: auto;
    }
    
    .toast {
        left: 1rem;
        right: 1rem;
        max-width: none;
    }
}