/* ==========================================================================
   CSS Variables & Design System
   ========================================================================== */
:root {
    /* Brand Colors */
    --color-primary: #0F172A;       /* Midnight Blue */
    --color-primary-light: #1E293B;
    --color-secondary: #10B981;     /* Emerald Medical Green */
    --color-secondary-hover: #059669;
    --color-accent: #3B82F6;        /* Professional Blue */
    --color-gold: #D4AF37;          /* Honor/Awards Gold */
    
    /* Backgrounds */
    --color-bg: #FFFFFF;
    --color-bg-light: #F8FAFC;
    --color-bg-subtle: #F1F5F9;
    
    /* Text */
    --color-text: #1E293B;
    --color-text-muted: #64748B;
    --color-text-light: #94A3B8;
    
    /* Functional */
    --color-white: #FFFFFF;
    --color-success: #10B981;
    --color-error: #EF4444;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    
    /* Radius */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 9999px;
    
    /* Spacing */
    --space-xl: 7rem;
    --transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==========================================================================
   Base Styles
   ========================================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

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

a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    letter-spacing: -0.025em;
    color: var(--color-primary);
    line-height: 1.2;
}

h2 { font-size: clamp(2rem, 5vw, 2.5rem); }
h3 { font-size: clamp(1.5rem, 4vw, 1.75rem); }

/* Layout Components */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section { padding: var(--space-xl) 0; }
.text-center { text-align: center; }
.mx-auto { margin-left: auto; margin-right: auto; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-5 { margin-top: 3rem; }
.mb-4 { margin-bottom: 2rem; }
.mb-5 { margin-bottom: 3rem; }
.opacity-70 { opacity: 0.7; }
.text-sm { font-size: 0.875rem; }
.w-100 { width: 100%; }

.section-title { margin-bottom: 1rem; }
.title-underline {
    width: 60px;
    height: 4px;
    background: var(--color-secondary);
    border-radius: 2px;
}
.text-center .title-underline { margin: 0 auto; }

.bg-light { background-color: var(--color-bg-light); }
.bg-primary { background-color: var(--color-primary); }
.text-white { color: var(--color-white); }

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 2rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: var(--transition);
    cursor: pointer;
    border: none;
    gap: 0.75rem;
}

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

.btn-primary:hover {
    background-color: var(--color-secondary-hover);
    transform: translateY(-2px);
    box-shadow: 0 10px 20px -5px rgba(16, 185, 129, 0.4);
}

.btn-outline-primary {
    background: transparent;
    border: 2px solid var(--color-secondary);
    color: var(--color-secondary);
}

.btn-outline-primary:hover {
    background: var(--color-secondary);
    color: var(--color-white);
}

.btn-lg { padding: 1rem 2.5rem; font-size: 1.125rem; }

/* Scroll Reveal */
.reveal-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: transform, opacity;
}

.reveal-on-scroll.active {
    opacity: 1;
    transform: translateY(0);
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 90px;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    z-index: 1000;
    border-bottom: 1px solid rgba(15, 23, 42, 0.05);
    transition: var(--transition);
}

.header.scrolled {
    height: 75px;
    box-shadow: var(--shadow-sm);
    background: rgba(255, 255, 255, 0.95);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.logo { display: flex; align-items: center; gap: 0.75rem; }
.logo-icon { font-size: 1.75rem; color: var(--color-secondary); }
.logo-title { font-size: 1.5rem; font-weight: 800; color: var(--color-primary); }
.logo-subtitle { font-size: 0.75rem; color: var(--color-text-muted); text-transform: uppercase; display: block; }

.nav-list { display: flex; gap: 2rem; }
.nav-link { font-weight: 600; font-size: 0.95rem; color: var(--color-primary); opacity: 0.8; }
.nav-link:hover, .nav-link.active { color: var(--color-secondary); opacity: 1; }

.header-actions { display: flex; align-items: center; gap: 1rem; }

.mobile-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--color-primary);
    cursor: pointer;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
    padding-top: 140px;
    padding-bottom: 80px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: radial-gradient(circle at 100% 0%, #F1F5F9 0%, #FFFFFF 70%);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 4rem;
    align-items: center;
}

.hero-superbadge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(16, 185, 129, 0.08);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: var(--radius-full);
    color: var(--color-secondary);
    font-weight: 700;
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
}

.pulse-dot {
    width: 8px;
    height: 8px;
    background: var(--color-secondary);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(16, 185, 129, 0); }
    100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.hero-title { font-size: clamp(2.5rem, 5vw, 4rem); margin-bottom: 1.5rem; }
.hero-title-sub { display: block; font-weight: 500; color: var(--color-text-muted); font-size: 0.6em; margin-top: 0.5rem; }

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-secondary);
    font-weight: 600;
    border-left: 4px solid var(--color-secondary);
    padding-left: 1.5rem;
    margin-bottom: 2rem;
}

.hero-badges-row { display: flex; flex-wrap: wrap; gap: 1rem; margin-bottom: 2.5rem; }
.info-badge {
    background: white;
    padding: 0.6rem 1.2rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    font-weight: 600;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    border: 1px solid rgba(15, 23, 42, 0.05);
}

.hero-aegis {
    background: var(--color-bg-subtle);
    padding: 1.25rem;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    margin-bottom: 2.5rem;
}

.hero-buttons { display: flex; gap: 1.25rem; }

.hero-visual-card {
    background: var(--color-primary);
    border-radius: var(--radius-lg);
    padding: 3rem;
    color: white;
    min-height: 400px;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    box-shadow: var(--shadow-xl);
    position: relative;
    overflow: hidden;
}

.hvc-icon-grid {
    position: absolute;
    top: 2rem;
    right: 2rem;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    opacity: 0.1;
}

.hvc-icon-grid i { font-size: 2.5rem; }

.hero-qr-card {
    background: white;
    padding: 1rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-top: 2rem;
}

.qr-img { width: 100px; height: 100px; border-radius: 4px; }
.qr-text { font-weight: 600; color: var(--color-primary); line-height: 1.3; }
.qr-text i { font-size: 1.5rem; color: var(--color-secondary); margin-bottom: 0.5rem; display: block; }

/* ==========================================================================
   Sections
   ========================================================================== */

/* About Goals */
.goal-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.goal-card {
    padding: 2rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-md);
    transition: var(--transition);
    border: 1px solid rgba(15, 23, 42, 0.05);
}
.goal-card:hover { background: white; border-color: var(--color-secondary); box-shadow: var(--shadow-lg); transform: translateY(-5px); }
.goal-icon { font-size: 2rem; color: var(--color-secondary); margin-bottom: 1.5rem; }

/* Stats */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.stat-card {
    text-align: center;
    padding: 3rem 2rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
}
.stat-number {
    display: block;
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, white, var(--color-secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.stat-label { font-weight: 600; opacity: 0.8; }

/* Audience */
.audience-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.audience-card {
    padding: 2.5rem 2rem;
    background: white;
    border-radius: var(--radius-md);
    text-align: center;
    box-shadow: var(--shadow-sm);
}
.audience-icon { font-size: 2.5rem; color: var(--color-secondary); margin-bottom: 1.5rem; }
.audience-card p { font-weight: 700; margin: 0; }

/* Program Tabs */
.tabs-container { max-width: 900px; margin-left: auto; margin-right: auto; }
.tab-nav { display: flex; gap: 1rem; margin-bottom: 3rem; }
.tab-btn {
    flex: 1;
    padding: 1.5rem;
    background: white;
    border: 1px solid var(--color-bg-subtle);
    border-radius: var(--radius-md);
    cursor: pointer;
    text-align: left;
    transition: var(--transition);
}
.tab-btn.active { border-color: var(--color-secondary); box-shadow: var(--shadow-md); }
.tab-btn span { display: block; font-size: 0.875rem; color: var(--color-text-muted); font-weight: 600; margin-bottom: 0.25rem; }
.tab-btn strong { font-size: 1.1rem; color: var(--color-primary); }

.tab-content { display: none; }
.tab-content.active { display: block; animation: fadeIn 0.5s ease; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.timeline-item {
    display: flex;
    gap: 2rem;
    padding-bottom: 2.5rem;
    border-left: 2px solid var(--color-bg-subtle);
    margin-left: 1rem;
    padding-left: 2rem;
    position: relative;
}
.timeline-item::before {
    content: '';
    position: absolute;
    left: -7px;
    top: 0;
    width: 12px;
    height: 12px;
    background: var(--color-secondary);
    border-radius: 50%;
}
.timeline-time { font-weight: 800; color: var(--color-secondary); min-width: 60px; }
.timeline-title { font-weight: 600; color: var(--color-primary); }

/* Exhibition */
.exhibition-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.exhibition-item {
    padding: 1.5rem;
    background: white;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: var(--shadow-sm);
}
.exhibition-item i { color: var(--color-secondary); font-size: 1.25rem; }

/* Masterclass */
.mc-card {
    background: var(--color-primary);
    border-radius: var(--radius-lg);
    padding: 4rem;
    color: white;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}
.mc-card .section-title { color: white; }
.mc-visual { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.mc-skill {
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-md);
    text-align: center;
}
.mc-skill i { font-size: 2rem; color: var(--color-secondary); margin-bottom: 1rem; display: block; }
.mc-skill span { font-weight: 600; font-size: 0.9rem; }

/* Awards */
.award-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 2rem; }
.award-card {
    background: white;
    padding: 3rem 2rem;
    border-radius: var(--radius-md);
    text-align: center;
    box-shadow: var(--shadow-sm);
    border-top: 4px solid var(--color-gold);
}
.award-icon { font-size: 2.5rem; color: var(--color-gold); margin-bottom: 1.5rem; }

/* Registration Form */
.registration-container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 4rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}
.reg-form { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
.form-group.full { grid-column: span 2; }
.form-group label { display: block; font-weight: 700; margin-bottom: 0.75rem; font-size: 0.9rem; }
.form-group input, .form-group select {
    width: 100%;
    padding: 1rem;
    border: 1px solid var(--color-bg-subtle);
    border-radius: var(--radius-sm);
    background: var(--color-bg-light);
    font-family: inherit;
    transition: var(--transition);
}
.form-group input:focus { outline: none; border-color: var(--color-secondary); background: white; }

/* Venue */
.venue-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.venue-address { font-weight: 700; color: var(--color-primary); font-size: 1.1rem; }
.venue-map-wrap { height: 450px; border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-lg); }
.venue-map-wrap iframe { width: 100%; height: 100%; border: none; }

/* FAQ */
.faq-container { max-width: 800px; margin: 0 auto; }
.faq-item { background: white; border-radius: var(--radius-md); margin-bottom: 1rem; box-shadow: var(--shadow-sm); overflow: hidden; }
.faq-question {
    width: 100%;
    padding: 1.5rem 2rem;
    background: none;
    border: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 700;
    color: var(--color-primary);
    font-size: 1.1rem;
    cursor: pointer;
    text-align: left;
}
.faq-question i { transition: var(--transition); color: var(--color-secondary); }
.faq-answer { max-height: 0; overflow: hidden; transition: var(--transition); padding: 0 2rem; }
.faq-item.active .faq-answer { max-height: 200px; padding-bottom: 2rem; }
.faq-item.active .faq-question i { transform: rotate(45deg); }

/* Footer */
.footer { background: #05101D; color: white; padding: 5rem 0 2rem; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 4rem; margin-bottom: 4rem; }
.footer-logo { display: flex; align-items: center; gap: 0.75rem; font-size: 1.5rem; font-weight: 800; margin-bottom: 1.5rem; }
.footer-links h4 { color: white; margin-bottom: 1.5rem; font-size: 1.1rem; }
.footer-links li { margin-bottom: 1rem; opacity: 0.7; font-size: 0.95rem; }
.footer-links a:hover { opacity: 1; color: var(--color-secondary); }
.social-links { display: flex; gap: 1rem; }
.social-link {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}
.social-link:hover { background: var(--color-secondary); }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, 0.05); padding-top: 2rem; display: flex; justify-content: space-between; font-size: 0.875rem; opacity: 0.5; }

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */

/* Large Desktop (1440px) */
@media (min-width: 1441px) {
    .container { max-width: 1400px; }
}

/* Medium Desktop (1200px) */
@media (max-width: 1200px) {
    .hero-grid, .venue-grid, .mc-card { gap: 2rem; }
    .footer-grid { gap: 2rem; }
}

/* Tablet Landscape (992px) */
@media (max-width: 992px) {
    .hero-grid, .mc-card, .venue-grid { grid-template-columns: 1fr; text-align: center; }
    .hero-subtitle { border-left: none; padding-left: 0; }
    .hero-buttons, .hero-badges-row { justify-content: center; }
    .hero-visual-card { min-height: 300px; }
    .hero-qr-card { justify-content: center; }
    
    .stats-grid, .audience-grid, .exhibition-grid { grid-template-columns: repeat(2, 1fr); }
    .award-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .goal-grid { grid-template-columns: 1fr; }
}

/* Tablet Portrait (768px) */
@media (max-width: 768px) {
    :root { --space-xl: 4rem; }
    .header { height: 70px; }
    .nav {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: white;
        height: 0;
        overflow: hidden;
        transition: 0.4s ease;
        box-shadow: var(--shadow-lg);
    }
    .nav.active { height: auto; padding-bottom: 2rem; }
    .nav-list { flex-direction: column; gap: 0; padding: 1rem 2rem; }
    .nav-link { display: block; padding: 1rem 0; border-bottom: 1px solid var(--color-bg-subtle); }
    .mobile-toggle { display: block; }
    .header-actions .btn { display: none; }
    
    .registration-container { padding: 2rem; }
    .reg-form { grid-template-columns: 1fr; }
    .form-group.full { grid-column: span 1; }
    
    .mc-card { padding: 2rem; }
}

/* Mobile (576px) */
@media (max-width: 576px) {
    .hero-title { font-size: 2.25rem; }
    .stats-grid, .audience-grid, .exhibition-grid, .award-grid, .footer-grid { grid-template-columns: 1fr; }
    .hero-buttons { flex-direction: column; }
    .tab-nav { flex-direction: column; }
    .stat-number { font-size: 2.5rem; }
}

/* Small Mobile (390px / 360px) */
@media (max-width: 390px) {
    .container { padding: 0 1.5rem; }
    .hero-title { font-size: 2rem; }
    .btn { width: 100%; }
    .hero-qr-card { flex-direction: column; text-align: center; }
}