/* ═══════════════════════════════════════════════════════════════════════════
   OPMD Lesion Detection — Design System
   Dark mode, glassmorphism, medical-grade aesthetic
   ═══════════════════════════════════════════════════════════════════════════ */

/* ── Google Fonts ──────────────────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ── CSS Custom Properties ─────────────────────────────────────────────── */
:root {
    /* Core palette */
    --bg-primary:      #0a0e1a;
    --bg-secondary:    #111827;
    --bg-card:         rgba(17, 24, 39, 0.65);
    --bg-card-hover:   rgba(17, 24, 39, 0.85);
    --bg-input:        rgba(30, 41, 59, 0.6);

    /* Glass effect */
    --glass-border:    rgba(255, 255, 255, 0.08);
    --glass-shadow:    0 8px 32px rgba(0, 0, 0, 0.4);
    --glass-blur:      16px;

    /* Accent – teal / cyan medical */
    --accent:          #06b6d4;
    --accent-dim:      rgba(6, 182, 212, 0.15);
    --accent-glow:     rgba(6, 182, 212, 0.3);
    --accent-gradient: linear-gradient(135deg, #06b6d4, #8b5cf6);

    /* Semantic colors */
    --success:         #10b981;
    --warning:         #f59e0b;
    --danger:          #ef4444;
    --info:            #3b82f6;

    /* Text */
    --text-primary:    #f1f5f9;
    --text-secondary:  #94a3b8;
    --text-muted:      #64748b;

    /* Sizing */
    --radius-sm:       8px;
    --radius-md:       12px;
    --radius-lg:       16px;
    --radius-xl:       24px;

    /* Transitions */
    --ease-out:        cubic-bezier(0.16, 1, 0.3, 1);
    --transition:      all 0.3s var(--ease-out);
}

/* ── Reset & Base ──────────────────────────────────────────────────────── */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

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

/* ── Animated background ───────────────────────────────────────────────── */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background:
        radial-gradient(ellipse 800px 600px at 20% 30%, rgba(6, 182, 212, 0.07), transparent),
        radial-gradient(ellipse 600px 400px at 80% 70%, rgba(139, 92, 246, 0.06), transparent);
    z-index: -1;
    pointer-events: none;
    animation: bgPulse 12s ease-in-out infinite alternate;
}

@keyframes bgPulse {
    0%   { opacity: 0.6; }
    100% { opacity: 1; }
}

/* ── Layout ────────────────────────────────────────────────────────────── */
.app-container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 2rem 1.5rem 4rem;
}

/* ── Header ────────────────────────────────────────────────────────────── */
.app-header {
    text-align: center;
    padding: 2rem 0 3rem;
}

.app-header__badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.35rem 1rem;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--accent);
    background: var(--accent-dim);
    border: 1px solid rgba(6, 182, 212, 0.2);
    border-radius: 100px;
    margin-bottom: 1rem;
}

.app-header__badge .pulse-dot {
    width: 6px;
    height: 6px;
    background: var(--accent);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50%      { opacity: 0.4; transform: scale(0.8); }
}

.app-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

.app-header p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 520px;
    margin: 0 auto;
}

/* ── Glass Card ────────────────────────────────────────────────────────── */
.glass-card {
    background: var(--bg-card);
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
    transition: var(--transition);
}

.glass-card:hover {
    border-color: rgba(255, 255, 255, 0.12);
}

/* ── Upload Zone ───────────────────────────────────────────────────────── */
.upload-section {
    margin-bottom: 2rem;
}

.upload-zone {
    position: relative;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    border: 2px dashed rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    transition: var(--transition);
    overflow: hidden;
}

.upload-zone::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient);
    opacity: 0;
    transition: opacity 0.4s ease;
    border-radius: inherit;
}

.upload-zone:hover,
.upload-zone.drag-over {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.upload-zone:hover::before,
.upload-zone.drag-over::before {
    opacity: 0.04;
}

.upload-zone__icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
    opacity: 0.6;
    transition: var(--transition);
}

.upload-zone:hover .upload-zone__icon {
    opacity: 1;
    transform: scale(1.1);
}

.upload-zone__title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.4rem;
}

.upload-zone__subtitle {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.upload-zone__file-input {
    display: none;
}

/* ── Image Preview (in upload zone) ────────────────────────────────────── */
.upload-preview {
    display: none;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.upload-preview.visible {
    display: flex;
}

.upload-preview__img {
    max-width: 100%;
    max-height: 240px;
    border-radius: var(--radius-md);
    object-fit: contain;
    border: 1px solid var(--glass-border);
}

.upload-preview__name {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.upload-placeholder.hidden {
    display: none;
}

/* ── Controls Row ──────────────────────────────────────────────────────── */
.controls-row {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.control-group {
    flex: 1;
    min-width: 180px;
}

.control-group label {
    display: block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}

.control-group .slider-value {
    color: var(--accent);
    font-weight: 700;
    font-variant-numeric: tabular-nums;
}

/* Slider styling */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    background: var(--bg-input);
    border-radius: 100px;
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 10px var(--accent-glow);
    cursor: pointer;
    transition: transform 0.2s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 10px var(--accent-glow);
    cursor: pointer;
    border: none;
}

/* ── Primary Button ────────────────────────────────────────────────────── */
.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 2rem;
    font-size: 0.95rem;
    font-weight: 600;
    font-family: inherit;
    color: #fff;
    background: var(--accent-gradient);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    min-width: 180px;
    position: relative;
    overflow: hidden;
}

.btn-primary::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0);
    transition: background 0.3s ease;
}

.btn-primary:hover:not(:disabled)::after {
    background: rgba(255, 255, 255, 0.1);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--accent-glow);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.btn-primary .spinner {
    display: none;
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

.btn-primary.loading .spinner {
    display: block;
}

.btn-primary.loading .btn-text {
    display: none;
}

@keyframes spin {
    100% { transform: rotate(360deg); }
}

/* ── Results Section ───────────────────────────────────────────────────── */
.results-section {
    display: none;
    animation: fadeInUp 0.5s var(--ease-out);
}

.results-section.visible {
    display: block;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ── Stats Bar ─────────────────────────────────────────────────────────── */
.stats-bar {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    padding: 1.25rem;
    text-align: center;
}

.stat-card__value {
    font-size: 1.8rem;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-variant-numeric: tabular-nums;
}

.stat-card__label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-top: 0.25rem;
}

/* ── Image Comparison ──────────────────────────────────────────────────── */
.image-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.image-panel {
    padding: 1rem;
    overflow: hidden;
}

.image-panel__header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.image-panel__header .dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.dot--original { background: var(--info); }
.dot--detected { background: var(--success); }

.image-panel img {
    width: 100%;
    border-radius: var(--radius-md);
    display: block;
    border: 1px solid var(--glass-border);
    transition: var(--transition);
}

.image-panel img:hover {
    border-color: var(--accent);
    box-shadow: 0 0 20px var(--accent-dim);
}

/* ── Detections Table ──────────────────────────────────────────────────── */
.detections-table-wrapper {
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.detections-table-wrapper h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.detections-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

.detections-table thead {
    border-bottom: 1px solid var(--glass-border);
}

.detections-table th {
    text-align: left;
    padding: 0.75rem 1rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.detections-table td {
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.detections-table tbody tr {
    transition: background 0.2s ease;
}

.detections-table tbody tr:hover {
    background: rgba(255, 255, 255, 0.03);
}

/* Class badge */
.class-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 600;
}

.class-badge--lesion {
    background: rgba(239, 68, 68, 0.12);
    color: #f87171;
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.class-badge--oral_cavity {
    background: rgba(59, 130, 246, 0.12);
    color: #60a5fa;
    border: 1px solid rgba(59, 130, 246, 0.2);
}

/* Confidence bar */
.confidence-cell {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.confidence-bar {
    flex: 1;
    height: 4px;
    background: var(--bg-input);
    border-radius: 100px;
    overflow: hidden;
    max-width: 80px;
}

.confidence-bar__fill {
    height: 100%;
    border-radius: 100px;
    background: var(--accent-gradient);
    transition: width 0.6s var(--ease-out);
}

.confidence-value {
    font-variant-numeric: tabular-nums;
    font-weight: 600;
    color: var(--text-primary);
    min-width: 48px;
}

/* ── Progress Bar ──────────────────────────────────────────────────────── */
.progress-container {
    margin-bottom: 2rem;
    animation: fadeInUp 0.4s var(--ease-out);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-input);
    border-radius: 100px;
    overflow: hidden;
    margin-bottom: 0.75rem;
}

.progress-bar__fill {
    height: 100%;
    background: var(--accent-gradient);
    width: 0%;
    transition: width 0.3s ease;
    box-shadow: 0 0 10px var(--accent-glow);
}

.progress-text {
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ── Results Gallery ───────────────────────────────────────────────────── */
.results-gallery {
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.results-gallery h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 1rem;
    max-height: 400px;
    overflow-y: auto;
    padding-right: 0.5rem;
}

/* Custom scrollbar for gallery */
.gallery-grid::-webkit-scrollbar {
    width: 6px;
}

.gallery-grid::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
}

.gallery-grid::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
}

.gallery-item {
    cursor: pointer;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 2px solid transparent;
    transition: var(--transition);
    position: relative;
    aspect-ratio: 1;
}

.gallery-item:hover {
    transform: scale(1.05);
    border-color: var(--glass-border);
}

.gallery-item.active {
    border-color: var(--accent);
    box-shadow: 0 0 15px var(--accent-glow);
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.gallery-item__badge {
    position: absolute;
    bottom: 5px;
    right: 5px;
    background: rgba(0, 0, 0, 0.6);
    color: #fff;
    font-size: 0.65rem;
    padding: 2px 6px;
    border-radius: 4px;
    backdrop-filter: blur(4px);
}

/* ── No detections message ─────────────────────────────────────────────── */
.no-detections {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--text-muted);
}

.no-detections__icon {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
    opacity: 0.5;
}

.no-detections__text {
    font-size: 1rem;
    font-weight: 500;
}

/* ── Reset / Upload Another ────────────────────────────────────────────── */
.reset-container {
    margin-top: 3rem;
    display: flex;
    justify-content: center;
    padding-bottom: 2rem;
}

.btn-secondary {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    padding: 0.75rem 2rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-secondary:hover {
    background: var(--glass-bg);
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

/* ── Error state ───────────────────────────────────────────────────────── */
.error-banner {
    display: none;
    padding: 1rem 1.5rem;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.25);
    border-radius: var(--radius-md);
    color: #fca5a5;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    animation: fadeInUp 0.3s var(--ease-out);
}

.error-banner.visible {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* ── Footer ────────────────────────────────────────────────────────────── */
.app-footer {
    text-align: center;
    padding: 2rem 0;
    color: var(--text-muted);
    font-size: 0.8rem;
    border-top: 1px solid var(--glass-border);
    margin-top: 3rem;
}

/* ── Responsive ────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
    .app-header h1 {
        font-size: 1.75rem;
    }

    .image-comparison {
        grid-template-columns: 1fr;
    }

    .controls-row {
        flex-direction: column;
    }

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

    .detections-table {
        font-size: 0.8rem;
    }

    .detections-table th,
    .detections-table td {
        padding: 0.5rem 0.6rem;
    }
}

@media (max-width: 480px) {
    .app-container {
        padding: 1rem;
    }

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

    .upload-zone {
        padding: 2rem 1rem;
    }
}