client/styles.css

/*
 * DermAI - Skin Lesion Segmentation Application
 * Modern Medical Theme Stylesheet
 * ============================================
 */

/* ===== CSS VARIABLES ===== */
:root {
    /* Primary Colors - Medical Purple/Blue */
    --primary-50: #f5f3ff;
    --primary-100: #ede9fe;
    --primary-200: #ddd6fe;
    --primary-300: #c4b5fd;
    --primary-400: #a78bfa;
    --primary-500: #8b5cf6;
    --primary-600: #7c3aed;
    --primary-700: #6d28d9;
    --primary-800: #5b21b6;
    --primary-900: #4c1d95;

    /* Accent Colors - Medical Pink/Magenta */
    --accent-400: #f472b6;
    --accent-500: #ec4899;
    --accent-600: #db2777;

    /* Success/Health Green */
    --success-400: #4ade80;
    --success-500: #22c55e;
    --success-600: #16a34a;

    /* Neutral Colors */
    --neutral-50: #fafafa;
    --neutral-100: #f4f4f5;
    --neutral-200: #e4e4e7;
    --neutral-300: #d4d4d8;
    --neutral-400: #a1a1aa;
    --neutral-500: #71717a;
    --neutral-600: #52525b;
    --neutral-700: #3f3f46;
    --neutral-800: #27272a;
    --neutral-900: #18181b;
    --neutral-950: #09090b;

    /* Semantic Colors */
    --bg-primary: #0a0a0f;
    --bg-secondary: #111118;
    --bg-tertiary: #18181f;
    --bg-card: rgba(24, 24, 31, 0.7);
    --bg-card-hover: rgba(30, 30, 40, 0.8);
    
    --text-primary: #fafafa;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #ec4899 100%);
    --gradient-accent: linear-gradient(135deg, #ec4899 0%, #f472b6 100%);
    --gradient-success: linear-gradient(135deg, #22c55e 0%, #4ade80 100%);
    --gradient-glass: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -4px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 40px rgba(139, 92, 246, 0.3);
    --shadow-glow-accent: 0 0 40px rgba(236, 72, 153, 0.3);

    /* Borders */
    --border-primary: 1px solid rgba(255, 255, 255, 0.1);
    --border-accent: 1px solid rgba(139, 92, 246, 0.3);
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
    --transition-spring: 300ms cubic-bezier(0.34, 1.56, 0.64, 1);

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

/* ===== RESET & BASE ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ===== ANIMATED BACKGROUND ===== */
.gradient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(ellipse at 20% 20%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(236, 72, 153, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 50%, rgba(139, 92, 246, 0.05) 0%, transparent 70%);
    pointer-events: none;
    z-index: -2;
}

.gradient-orbs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
    overflow: hidden;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
    animation: float 20s ease-in-out infinite;
}

.orb-1 {
    width: 500px;
    height: 500px;
    background: var(--primary-600);
    top: -200px;
    right: -100px;
    animation-delay: 0s;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: var(--accent-500);
    bottom: -150px;
    left: -100px;
    animation-delay: -7s;
}

.orb-3 {
    width: 300px;
    height: 300px;
    background: var(--primary-500);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -14s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(30px, -30px) scale(1.05); }
    50% { transform: translate(-20px, 20px) scale(0.95); }
    75% { transform: translate(-30px, -20px) scale(1.02); }
}

/* ===== APP CONTAINER ===== */
.app-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ===== HEADER ===== */
.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 0;
    border-bottom: var(--border-primary);
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(10, 10, 15, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: all var(--transition-base);
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.logo-text .highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
}

.status-badge {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border: var(--border-primary);
    border-radius: var(--radius-full);
    backdrop-filter: blur(10px);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--neutral-500);
    animation: pulse 2s ease-in-out infinite;
}

.status-badge.online .status-dot {
    background: var(--success-500);
}

.status-badge.offline .status-dot {
    background: #ef4444;
}

.status-text {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* ===== MAIN CONTENT ===== */
.main-content {
    flex: 1;
    padding: 3rem 0;
}

/* ===== HERO SECTION ===== */
.hero {
    text-align: center;
    margin-bottom: 3rem;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1rem;
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ===== UPLOAD SECTION ===== */
.upload-section {
    margin-bottom: 3rem;
}

.upload-card {
    background: var(--bg-card);
    border: 2px dashed rgba(139, 92, 246, 0.3);
    border-radius: var(--radius-2xl);
    padding: 4rem 2rem;
    text-align: center;
    transition: all var(--transition-base);
    cursor: pointer;
    backdrop-filter: blur(10px);
}

.upload-card:hover,
.upload-card.dragover {
    border-color: var(--primary-500);
    background: var(--bg-card-hover);
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}

.upload-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    color: var(--primary-400);
    opacity: 0.8;
}

.upload-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.upload-subtitle {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.upload-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    background: var(--gradient-primary);
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(139, 92, 246, 0.2);
}

.upload-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl), 0 0 30px rgba(139, 92, 246, 0.3);
}

.upload-btn svg {
    width: 18px;
    height: 18px;
}

/* ===== RESULTS SECTION ===== */
.results-section {
    animation: fadeIn 0.5s ease-out;
}

.results-section.hidden {
    display: none;
}

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

.results-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.result-card {
    background: var(--bg-card);
    border: var(--border-primary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    backdrop-filter: blur(10px);
    transition: all var(--transition-base);
}

.result-card:hover {
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.card-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 1.25rem;
    border-bottom: var(--border-primary);
    background: rgba(255, 255, 255, 0.02);
}

.card-icon {
    font-size: 1.25rem;
}

.card-title {
    font-size: 0.9rem;
    font-weight: 600;
}

.image-container {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--neutral-950);
    padding: 1rem;
}

.image-container img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: var(--radius-md);
}

/* ===== METRICS PANEL ===== */
.metrics-panel {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.metric-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border: var(--border-primary);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    transition: all var(--transition-base);
}

.metric-card:hover {
    border-color: rgba(139, 92, 246, 0.3);
    transform: translateY(-2px);
}

.metric-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-lg);
    flex-shrink: 0;
}

.metric-icon svg {
    width: 24px;
    height: 24px;
}

.confidence-icon {
    background: rgba(34, 197, 94, 0.1);
    color: var(--success-400);
}

.area-icon {
    background: rgba(139, 92, 246, 0.1);
    color: var(--primary-400);
}

.model-icon {
    background: rgba(236, 72, 153, 0.1);
    color: var(--accent-400);
}

.metric-content {
    display: flex;
    flex-direction: column;
}

.metric-value {
    font-size: 1.5rem;
    font-weight: 700;
    line-height: 1.2;
}

.metric-value.model-name {
    font-size: 1rem;
    font-family: var(--font-mono);
}

.metric-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* ===== ACTION BUTTONS ===== */
.action-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    font-weight: 600;
    font-size: 0.9rem;
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
}

.btn svg {
    width: 18px;
    height: 18px;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md), 0 0 20px rgba(139, 92, 246, 0.2);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 30px rgba(139, 92, 246, 0.3);
}

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

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: rgba(139, 92, 246, 0.3);
}

/* ===== LOADING OVERLAY ===== */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(10, 10, 15, 0.9);
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.loading-overlay.hidden {
    display: none;
}

.loading-content {
    text-align: center;
}

.loading-spinner {
    width: 80px;
    height: 80px;
    position: relative;
    margin: 0 auto 1.5rem;
}

.spinner-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    border: 3px solid transparent;
    animation: spin 1.5s linear infinite;
}

.spinner-ring:nth-child(1) {
    border-top-color: var(--primary-500);
    animation-delay: 0s;
}

.spinner-ring:nth-child(2) {
    width: 60%;
    height: 60%;
    top: 20%;
    left: 20%;
    border-right-color: var(--accent-500);
    animation-delay: 0.2s;
    animation-direction: reverse;
}

.spinner-ring:nth-child(3) {
    width: 30%;
    height: 30%;
    top: 35%;
    left: 35%;
    border-bottom-color: var(--success-500);
    animation-delay: 0.4s;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.loading-text {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.loading-subtext {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* ===== INFO SECTIONS ===== */
.info-section {
    padding: 4rem 0;
    border-top: var(--border-primary);
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
}

.section-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

/* ===== FEATURES GRID ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.feature-card {
    padding: 2rem;
    background: var(--bg-card);
    border: var(--border-primary);
    border-radius: var(--radius-xl);
    text-align: center;
    transition: all var(--transition-base);
    backdrop-filter: blur(10px);
}

.feature-card:hover {
    border-color: rgba(139, 92, 246, 0.3);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: white;
}

.feature-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== TECH GRID ===== */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.tech-card {
    padding: 1.5rem;
    background: var(--bg-card);
    border: var(--border-primary);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
    backdrop-filter: blur(10px);
}

.tech-card:hover {
    border-color: rgba(139, 92, 246, 0.3);
    transform: translateY(-2px);
}

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

.tech-badge {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.25rem 0.5rem;
    background: var(--gradient-primary);
    color: white;
    border-radius: var(--radius-sm);
}

.tech-header h3 {
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font-mono);
}

.tech-card p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== DISCLAIMER ===== */
.disclaimer {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: rgba(234, 179, 8, 0.1);
    border: 1px solid rgba(234, 179, 8, 0.3);
    border-radius: var(--radius-xl);
    margin: 2rem 0;
}

.disclaimer-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.disclaimer p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.disclaimer strong {
    color: #fbbf24;
}

/* ===== FOOTER ===== */
.footer {
    padding: 2rem 0;
    text-align: center;
    border-top: var(--border-primary);
}

.footer p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.footer-tech {
    font-size: 0.75rem;
    margin-top: 0.5rem;
    font-family: var(--font-mono);
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .results-grid .overlay-card {
        grid-column: span 2;
    }
    
    .metrics-panel {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .metrics-panel .metric-card:last-child {
        grid-column: span 2;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid .feature-card:last-child {
        grid-column: span 2;
    }
}

@media (max-width: 768px) {
    .app-container {
        padding: 0 1rem;
    }
    
    .header {
        flex-wrap: wrap;
        gap: 1rem;
    }
    
    .nav {
        order: 3;
        width: 100%;
        justify-content: center;
        gap: 1.5rem;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .results-grid .overlay-card {
        grid-column: span 1;
    }
    
    .metrics-panel {
        grid-template-columns: 1fr;
    }
    
    .metrics-panel .metric-card:last-child {
        grid-column: span 1;
    }
    
    .features-grid,
    .tech-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid .feature-card:last-child {
        grid-column: span 1;
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .action-buttons .btn {
        width: 100%;
        justify-content: center;
    }
    
    .upload-card {
        padding: 2.5rem 1.5rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.75rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .metric-card {
        flex-direction: column;
        text-align: center;
    }
}

/* ===== UTILITY CLASSES ===== */
.hidden {
    display: none !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}