:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a25;
    --bg-hover: #252535;
    --accent-primary: #6366f1;
    --accent-secondary: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.3);
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border-color: #2a2a3a;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
}

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

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

.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.hidden {
    display: none !important;
}

.login-box {
    margin: auto;
    width: 100%;
    max-width: 400px;
    padding: 48px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-md);
    margin-bottom: 24px;
    color: white;
}

.login-box h1 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.input-group {
    margin-bottom: 20px;
}

.input-group input {
    width: 100%;
    padding: 14px 18px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.input-group input::placeholder {
    color: var(--text-muted);
}

.btn-primary {
    width: 100%;
    padding: 14px 24px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    padding: 10px 20px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: background var(--transition-fast), border-color var(--transition-fast);
}

.btn-secondary:hover {
    background: var(--bg-hover);
    border-color: var(--text-muted);
}

.btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    cursor: pointer;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.btn-icon:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.btn-danger {
    padding: 8px 16px;
    background: transparent;
    border: 1px solid var(--error);
    border-radius: var(--radius-sm);
    color: var(--error);
    font-size: 0.75rem;
    font-weight: 500;
    cursor: pointer;
    transition: background var(--transition-fast);
}

.btn-danger:hover {
    background: rgba(239, 68, 68, 0.1);
}

.error-text {
    color: var(--error);
    font-size: 0.875rem;
    margin-top: 16px;
    min-height: 20px;
}

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 32px;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--accent-primary);
}

.header-left h1 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.main-content {
    flex: 1;
    padding: 32px;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.upload-section,
.files-section {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 24px;
}

.upload-section h2,
.files-section h2 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.upload-zone {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 48px 24px;
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: border-color var(--transition-fast), background var(--transition-fast);
    color: var(--text-secondary);
}

.upload-zone:hover,
.upload-zone.dragover {
    border-color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.05);
}

.upload-zone svg {
    margin-bottom: 16px;
    color: var(--accent-primary);
}

.upload-zone p {
    margin-bottom: 8px;
}

.upload-zone .hint {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.upload-progress {
    margin-top: 20px;
}

.progress-bar {
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    border-radius: 4px;
    width: 0%;
    transition: width var(--transition-fast);
}

#progress-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 8px;
    text-align: center;
}

.files-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.files-header h2 {
    margin-bottom: 0;
}

.files-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 18px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.file-item:hover {
    background: var(--bg-hover);
}

.file-info {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
    min-width: 0;
}

.file-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
    color: var(--accent-primary);
    flex-shrink: 0;
}

.file-details {
    min-width: 0;
}

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

.file-meta {
    font-size: 0.75rem;
    color: var(--text-muted);
    display: flex;
    gap: 12px;
}

.file-actions {
    display: flex;
    gap: 8px;
}

.file-link {
    color: var(--accent-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    padding: 8px 16px;
    background: rgba(99, 102, 241, 0.1);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.file-link:hover {
    background: rgba(99, 102, 241, 0.2);
}

.loading {
    text-align: center;
    color: var(--text-muted);
    padding: 32px;
}

.empty-state {
    text-align: center;
    color: var(--text-muted);
    padding: 48px;
}

.toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    padding: 16px 24px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    animation: slideIn 0.3s ease;
}

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

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

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@media (max-width: 768px) {
    .login-box {
        margin: 24px;
        padding: 32px 24px;
    }

    .header {
        padding: 12px 16px;
    }

    .main-content {
        padding: 16px;
    }

    .file-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .file-actions {
        width: 100%;
        justify-content: flex-end;
    }
}