:root {
    --slate-50: #f8fafc;
    --slate-100: #f1f5f9;
    --slate-200: #e2e8f0;
    --slate-300: #cbd5e1;
    --slate-400: #94a3b8;
    --slate-500: #64748b;
    --slate-600: #475569;
    --slate-700: #334155;
    --slate-800: #1e293b;
    --slate-900: #0f172a;
    --indigo-50: #eef2ff;
    --indigo-600: #4f46e5;
    --indigo-700: #4338ca;
    --success-bg: #dcfce7;
    --success-text: #166534;
    --warn-bg: #fef3c7;
    --warn-text: #92400e;
    --danger-bg: #fee2e2;
    --danger-text: #991b1b;
    --bs-body-bg: var(--slate-50);
    --bs-body-color: var(--slate-900);
    --border-color: var(--slate-200);
    --preview-surface: #f8fafc;
    --preview-canvas-bg: #ffffff;
    --preview-number-color: #312e81;
}

[data-bs-theme="dark"] {
    --bs-body-bg: var(--slate-900);
    --bs-body-color: var(--slate-100);
    --bs-border-color: var(--slate-700);
    --border-color: var(--slate-700);
    --preview-surface: #111827;
    --preview-canvas-bg: #1f2937;
    --preview-number-color: #c7d2fe;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bs-body-bg);
    color: var(--bs-body-color);
}

::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--slate-300);
    border-radius: 4px;
}

[data-bs-theme="dark"] ::-webkit-scrollbar-thumb {
    background: var(--slate-600);
}

.app-header {
    background-color: var(--indigo-600);
    color: white;
    padding: 1.25rem 1rem;
    text-align: center;
    position: relative;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

[data-bs-theme="dark"] .app-header {
    background-color: #1a1a2e;
}

.app-header h1 {
    font-size: 1.35rem !important;
    margin: 0;
}

.app-header p {
    color: rgba(255, 255, 255, 0.86) !important;
}

.theme-fab {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--bs-body-bg);
    border: 1px solid var(--border-color);
    color: var(--bs-body-color);
    width: 42px;
    height: 42px;
    font-size: 20px;
    font-weight: 700;
    border-radius: 0.75rem;
    cursor: pointer;
    z-index: 10;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.theme-fab:hover {
    background: var(--border-color);
}

.card-custom {
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

[data-bs-theme="dark"] .card-custom {
    background-color: var(--slate-800);
}

.card-header-custom {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border-color);
    background-color: rgba(248, 250, 252, 0.6);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

[data-bs-theme="dark"] .card-header-custom {
    background-color: rgba(30, 41, 59, 0.85);
}

.btn-primary-custom {
    background-color: var(--indigo-600);
    color: white;
    border-radius: 9999px;
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    border: none;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.12);
    transition: all 0.2s;
}

.btn-primary-custom:hover:not(:disabled) {
    background-color: var(--indigo-700);
    color: white;
}

.btn-primary-custom:disabled {
    opacity: 0.55;
    cursor: not-allowed;
    box-shadow: none;
}

.btn-upload {
    color: var(--indigo-600);
    font-size: 0.9rem;
    font-weight: 600;
    background: transparent;
    border: none;
    padding: 0.4rem 0.7rem;
    border-radius: 0.375rem;
    transition: background 0.2s;
}

.btn-upload:hover {
    background-color: var(--indigo-50);
}

[data-bs-theme="dark"] .btn-upload {
    color: #818cf8;
}

[data-bs-theme="dark"] .btn-upload:hover {
    background-color: rgba(79, 70, 229, 0.28);
}

.drop-zone {
    border: 2px dashed var(--slate-300);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.06), rgba(255, 255, 255, 0.75));
    padding: 2rem 1.25rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.drop-zone:hover,
.drop-zone:focus,
.drop-zone.is-dragover {
    border-color: var(--indigo-600);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.12), rgba(255, 255, 255, 0.9));
    outline: none;
}

[data-bs-theme="dark"] .drop-zone {
    border-color: var(--slate-600);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.18), rgba(30, 41, 59, 0.82));
}

.drop-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 72px;
    height: 72px;
    border-radius: 18px;
    background-color: var(--indigo-600);
    color: white;
    font-weight: 700;
    letter-spacing: 0.08em;
    margin-bottom: 1rem;
}

.range-value {
    font-size: 0.9rem;
    color: var(--slate-500);
}

[data-bs-theme="dark"] .range-value,
[data-bs-theme="dark"] .text-secondary,
[data-bs-theme="dark"] .form-text {
    color: var(--slate-400) !important;
}

.divider {
    border-top: 1px solid var(--border-color);
}

.status-banner {
    border-radius: 0.75rem;
    padding: 0.9rem 1rem;
    font-size: 0.95rem;
}

.status-banner.success {
    background-color: var(--success-bg);
    color: var(--success-text);
}

.status-banner.warning {
    background-color: var(--warn-bg);
    color: var(--warn-text);
}

.status-banner.error {
    background-color: var(--danger-bg);
    color: var(--danger-text);
}

[data-bs-theme="dark"] .status-banner.success {
    background-color: rgba(22, 101, 52, 0.28);
    color: #86efac;
}

[data-bs-theme="dark"] .status-banner.warning {
    background-color: rgba(146, 64, 14, 0.32);
    color: #fcd34d;
}

[data-bs-theme="dark"] .status-banner.error {
    background-color: rgba(153, 27, 27, 0.35);
    color: #fca5a5;
}

.progress-custom {
    height: 12px;
    background-color: rgba(148, 163, 184, 0.18);
}

.progress-custom .progress-bar {
    background: linear-gradient(90deg, var(--indigo-600), #7c3aed);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.75rem;
}

.stat-card {
    border: 1px solid var(--border-color);
    padding: 0.9rem;
    background-color: rgba(248, 250, 252, 0.8);
    border-radius: 0.75rem;
}

[data-bs-theme="dark"] .stat-card {
    background-color: rgba(15, 23, 42, 0.5);
}

.stat-label {
    display: block;
    font-size: 0.78rem;
    color: var(--slate-500);
    margin-bottom: 0.35rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

[data-bs-theme="dark"] .stat-label {
    color: var(--slate-400);
}

.preview-shell {
    position: relative;
    background-color: var(--preview-surface);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    min-height: 400px;
    padding: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

[data-bs-theme="dark"] .preview-shell {
    background-color: var(--preview-surface);
}

.preview-canvas {
    max-width: 100%;
    height: auto;
    display: block;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    box-shadow: 0 12px 24px rgba(15, 23, 42, 0.12);
    background: var(--preview-canvas-bg);
}

.preview-empty {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 1.75rem;
    background-color: var(--preview-surface);
    color: var(--slate-500);
    font-size: 0.95rem;
    line-height: 1.6;
}

[data-bs-theme="dark"] .preview-empty {
    color: var(--slate-400);
}

.feature-list {
    padding-left: 1.15rem;
}

.feature-list li + li {
    margin-top: 0.45rem;
}

.info-copy {
    padding-bottom: 1rem;
}

.info-badge {
    background-color: rgba(79, 70, 229, 0.1);
    color: var(--indigo-600);
    border: 1px solid rgba(79, 70, 229, 0.18);
}

[data-bs-theme="dark"] .info-badge {
    background-color: rgba(129, 140, 248, 0.15);
    color: #c7d2fe;
    border-color: rgba(129, 140, 248, 0.22);
}

footer {
    width: 100%;
    padding: 2rem;
    background-color: white;
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.9rem;
    color: var(--slate-500);
}

[data-bs-theme="dark"] footer {
    background-color: var(--slate-800);
}

.footer-link {
    color: var(--slate-500);
    text-decoration: none;
    margin: 0 0.5rem;
    transition: color 0.2s;
}

.footer-link:hover {
    color: var(--indigo-600);
}

[data-bs-theme="dark"] .footer-link {
    color: var(--slate-400);
}

[data-bs-theme="dark"] .footer-link:hover {
    color: #818cf8;
}

@media (max-width: 767.98px) {
    .theme-fab {
        top: 0.75rem;
        right: 0.75rem;
    }

    .card-header-custom {
        flex-direction: column;
        align-items: flex-start;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }

    .preview-shell {
        min-height: 320px;
    }
}

.generic-output-card {
    border: 1px solid var(--border-color);
    padding: 0.9rem 1rem;
    background-color: rgba(248, 250, 252, 0.8);
    border-radius: 0.75rem;
}

[data-bs-theme="dark"] .generic-output-card {
    background-color: rgba(15, 23, 42, 0.5);
}