/* ==========================================================================
   11th EFEPR Summer School - Modern Design System & Styles
   Barcelona, 29 August - 4 September 2027
   ========================================================================== */

/* --- CSS Variables & Design Tokens --- */
:root {
  /* Brand Palette */
  --bg-primary: #070d18;
  --bg-secondary: #0e172a;
  --bg-tertiary: #162238;
  --bg-card: rgba(22, 34, 56, 0.72);
  --bg-card-hover: rgba(30, 47, 78, 0.85);
  --bg-glass: rgba(14, 23, 42, 0.75);
  --bg-glass-light: rgba(255, 255, 255, 0.05);

  /* Accents */
  --accent-cyan: #00d2ff;
  --accent-blue: #3a86ff;
  --accent-navy: #0056b3;
  --accent-amber: #f59e0b;
  --accent-coral: #ff6b6b;
  --accent-gold: #fbbf24;
  --accent-emerald: #10b981;

  /* Gradients */
  --grad-primary: linear-gradient(135deg, #00d2ff 0%, #3a86ff 100%);
  --grad-amber: linear-gradient(135deg, #fbbf24 0%, #f59e0b 50%, #e07a5f 100%);
  --grad-card: linear-gradient(145deg, rgba(255, 255, 255, 0.07) 0%, rgba(255, 255, 255, 0.02) 100%);
  --grad-card-glow: linear-gradient(145deg, rgba(0, 210, 255, 0.15) 0%, rgba(58, 134, 255, 0.05) 100%);
  --grad-dark-overlay: linear-gradient(180deg, rgba(7, 13, 24, 0.4) 0%, rgba(7, 13, 24, 0.85) 65%, #070d18 100%);
  --grad-hero-radial: radial-gradient(circle at 50% 30%, rgba(0, 210, 255, 0.18) 0%, rgba(58, 134, 255, 0.08) 50%, transparent 80%);

  /* Text Colors */
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --text-accent: #38bdf8;

  /* Borders & Shadows */
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-medium: rgba(255, 255, 255, 0.15);
  --border-highlight: rgba(0, 210, 255, 0.4);
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 10px 25px -5px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 40px -10px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 35px rgba(0, 210, 255, 0.25);
  --shadow-glow-amber: 0 0 30px rgba(245, 158, 11, 0.2);

  /* Layout & Spacing */
  --container-max: 1240px;
  --header-height: 80px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  /* Typography */
  --font-main: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-heading: 'Outfit', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Transitions */
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(at 0% 0%, rgba(58, 134, 255, 0.07) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(0, 210, 255, 0.05) 0px, transparent 50%),
    radial-gradient(at 50% 50%, rgba(245, 158, 11, 0.03) 0px, transparent 50%);
  background-attachment: fixed;
}

img, picture, svg, video {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

p {
  color: var(--text-secondary);
}

/* --- Layout Utility --- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.section {
  padding: 6rem 0;
  position: relative;
}

.section-dark {
  background-color: rgba(10, 18, 33, 0.6);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

/* --- Section Header Component --- */
.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 3.5rem auto;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  border-radius: var(--radius-full);
  background: rgba(0, 210, 255, 0.1);
  border: 1px solid rgba(0, 210, 255, 0.25);
  color: var(--accent-cyan);
  font-size: 0.825rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}

.section-tag-amber {
  background: rgba(245, 158, 11, 0.12);
  border-color: rgba(245, 158, 11, 0.3);
  color: var(--accent-gold);
}

.section-title {
  font-size: clamp(2rem, 3.5vw, 2.75rem);
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  font-family: var(--font-main);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius-full);
  transition: all var(--transition-normal);
  white-space: nowrap;
}

.btn-primary {
  background: var(--grad-primary);
  color: #070d18;
  box-shadow: 0 4px 20px rgba(0, 210, 255, 0.35);
  font-weight: 700;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 210, 255, 0.55);
  filter: brightness(1.05);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-primary);
  border: 1px solid var(--border-medium);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: var(--accent-cyan);
  color: #fff;
  transform: translateY(-2px);
}

.btn-amber {
  background: var(--grad-amber);
  color: #0f172a;
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.3);
  font-weight: 700;
}

.btn-amber:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.5);
}

.btn-sm {
  padding: 0.5rem 1.1rem;
  font-size: 0.85rem;
}

/* ==========================================================================
   Header & Navbar
   ========================================================================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  z-index: 1000;
  transition: all var(--transition-normal);
  background: transparent;
}

.header.scrolled {
  background: rgba(7, 13, 24, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  height: 72px;
}

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

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  z-index: 1001;
}

.brand-logo-img {
  height: 48px;
  width: auto;
  object-fit: contain;
  transition: transform var(--transition-fast);
}

.brand-link:hover .brand-logo-img {
  transform: scale(1.05);
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.1rem;
  color: #fff;
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.brand-title span {
  background: var(--grad-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.brand-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.02em;
}

/* Nav Links */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  position: relative;
  padding: 0.4rem 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--grad-primary);
  transition: width var(--transition-normal);
  border-radius: var(--radius-full);
}

.nav-link:hover,
.nav-link.active {
  color: #fff;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

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

/* Mobile Toggle */
.mobile-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  z-index: 1001;
}

.mobile-toggle span {
  width: 20px;
  height: 2px;
  background-color: #fff;
  border-radius: 2px;
  transition: all var(--transition-normal);
}

.mobile-toggle span:not(:last-child) {
  margin-bottom: 5px;
}

.mobile-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.mobile-toggle.open span:nth-child(2) {
  opacity: 0;
}

.mobile-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero-section {
  position: relative;
  min-height: calc(85vh - var(--header-height));
  display: flex;
  align-items: center;
  padding-top: calc(var(--header-height) + 3rem);
  padding-bottom: 3.5rem;
  overflow: hidden;
}

/* Hero Background Visuals */
.hero-bg-wrapper {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  overflow: hidden;
}

.hero-bg-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  filter: saturate(1.15) brightness(0.65);
  transform: scale(1.03);
  animation: heroZoom 25s ease-in-out infinite alternate;
}

@keyframes heroZoom {
  0% { transform: scale(1.02); }
  100% { transform: scale(1.08); }
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    180deg,
    rgba(7, 13, 24, 0.75) 0%,
    rgba(7, 13, 24, 0.85) 45%,
    #070d18 100%
  );
}

.hero-glow-orb {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(140px);
  pointer-events: none;
  opacity: 0.35;
}

.hero-glow-1 {
  top: 10%;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 210, 255, 0.4);
}

.hero-glow-2 {
  bottom: 10%;
  right: 5%;
  background: rgba(245, 158, 11, 0.25);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 960px;
  margin: 0 auto;
}

.hero-badge-group {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 2rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 1.1rem;
  background: rgba(14, 23, 42, 0.8);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-primary);
  box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

.hero-badge.highlight {
  border-color: rgba(0, 210, 255, 0.4);
  color: var(--accent-cyan);
  background: rgba(0, 210, 255, 0.1);
}

.hero-title {
  font-size: clamp(2.5rem, 5.5vw, 4.25rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.12;
  margin-bottom: 1.5rem;
}

.hero-title-gradient {
  background: linear-gradient(135deg, #ffffff 30%, #00d2ff 75%, #3a86ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  color: var(--text-secondary);
  line-height: 1.65;
  max-width: 820px;
  margin: 0 auto 2.5rem auto;
}

.hero-meta-bar {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 1.5rem 2.5rem;
  padding: 1rem 2rem;
  background: rgba(14, 23, 42, 0.85);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-xl);
  margin-bottom: 2.75rem;
  box-shadow: var(--shadow-lg);
}

.hero-meta-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-align: left;
}

.hero-meta-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: rgba(0, 210, 255, 0.12);
  border: 1px solid rgba(0, 210, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 1.2rem;
}

.hero-meta-icon.amber {
  background: rgba(245, 158, 11, 0.15);
  border-color: rgba(245, 158, 11, 0.3);
  color: var(--accent-gold);
}

.hero-meta-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
}

.hero-meta-value {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
}

/* Quick Highlights Ribbon */
.hero-ribbon {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin-top: 4.5rem;
  position: relative;
  z-index: 2;
}

.ribbon-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  transition: all var(--transition-normal);
}

.ribbon-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow-glow);
}

.ribbon-icon {
  font-size: 1.5rem;
  color: var(--accent-cyan);
  padding: 0.6rem;
  background: rgba(0, 210, 255, 0.1);
  border-radius: var(--radius-sm);
  line-height: 1;
}

.ribbon-card h4 {
  font-size: 1rem;
  margin-bottom: 0.25rem;
  color: #fff;
}

.ribbon-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.4;
}

/* ==========================================================================
   About Section
   ========================================================================== */
.about-grid {
  max-width: 880px;
  margin: 0 auto;
}

.about-content h3 {
  font-size: 2.2rem;
  margin-bottom: 1.25rem;
  line-height: 1.25;
  color: #fff;
}

.about-lead {
  font-size: 1.15rem;
  color: var(--text-primary);
  font-weight: 500;
  margin-bottom: 1.25rem;
  line-height: 1.7;
}

.about-text {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

.about-features-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2rem;
}

.about-feature-item {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  padding: 1rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.about-feature-item:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(0, 210, 255, 0.3);
}

.about-feature-icon {
  color: var(--accent-cyan);
  font-size: 1.25rem;
  margin-top: 2px;
}

.about-cards-column {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.about-highlight-box {
  background: linear-gradient(145deg, rgba(14, 23, 42, 0.9) 0%, rgba(22, 34, 56, 0.8) 100%);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.about-highlight-box::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--grad-primary);
}

.about-highlight-box h4 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
  color: #fff;
}

.about-highlight-box p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ==========================================================================
   Scientific Programme Section
   ========================================================================== */
.scientific-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.75rem;
}

.topic-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  position: relative;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.topic-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--grad-primary);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.topic-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 210, 255, 0.35);
  background: var(--bg-card-hover);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5), 0 0 25px rgba(0, 210, 255, 0.15);
}

.topic-card:hover::after {
  opacity: 1;
}

.topic-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.topic-icon {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-md);
  background: rgba(0, 210, 255, 0.1);
  border: 1px solid rgba(0, 210, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 1.4rem;
  flex-shrink: 0;
}

.topic-number {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-cyan);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.topic-title {
  font-size: 1.35rem;
  color: #fff;
}

.topic-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.programme-notice {
  margin-top: 3.5rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px dashed var(--border-medium);
  border-radius: var(--radius-md);
  padding: 1.5rem 2rem;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.programme-notice i {
  color: var(--accent-cyan);
  font-size: 1.25rem;
}

/* ==========================================================================
   Practical Training Spotlight (Wednesday)
   ========================================================================== */
.practical-showcase {
  background: radial-gradient(circle at 80% 20%, rgba(0, 210, 255, 0.15) 0%, transparent 60%),
              linear-gradient(145deg, #0e1a2f 0%, #091322 100%);
  border: 1px solid rgba(0, 210, 255, 0.3);
  border-radius: var(--radius-xl);
  padding: 3.5rem 3rem;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.practical-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
  align-items: center;
}

.practical-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  border-radius: var(--radius-full);
  background: var(--grad-amber);
  color: #070d18;
  font-weight: 800;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.practical-title {
  font-size: clamp(2rem, 3.5vw, 2.5rem);
  color: #fff;
  margin-bottom: 1.25rem;
}

.practical-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 1.75rem;
}

.practical-highlights {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.practical-item {
  background: rgba(7, 13, 24, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  transition: all var(--transition-fast);
}

.practical-item:hover {
  border-color: var(--accent-cyan);
  background: rgba(7, 13, 24, 0.8);
}

.practical-item h5 {
  font-size: 1rem;
  color: #fff;
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.practical-item h5 i {
  color: var(--accent-cyan);
}

.practical-item p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.practical-visual-card {
  background: rgba(14, 23, 42, 0.8);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-lg);
  padding: 2rem;
  text-align: center;
  position: relative;
}

.practical-visual-icon {
  font-size: 3.5rem;
  color: var(--accent-cyan);
  margin-bottom: 1.25rem;
  display: inline-block;
  animation: floatIcon 4s ease-in-out infinite alternate;
}

@keyframes floatIcon {
  0% { transform: translateY(0px) rotate(0deg); }
  100% { transform: translateY(-8px) rotate(4deg); }
}

.practical-visual-card h4 {
  font-size: 1.25rem;
  color: #fff;
  margin-bottom: 0.75rem;
}

.practical-visual-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   Preliminary Schedule / Interactive Timeline
   ========================================================================== */
.schedule-tabs-container {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding-bottom: 0.5rem;
  margin-bottom: 2.5rem;
  scrollbar-width: thin;
  scrollbar-color: var(--border-medium) transparent;
}

.schedule-tabs-container::-webkit-scrollbar {
  height: 6px;
}

.schedule-tabs-container::-webkit-scrollbar-thumb {
  background: var(--border-medium);
  border-radius: 4px;
}

.tab-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0.85rem 1.4rem;
  background: rgba(14, 23, 42, 0.7);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  font-weight: 600;
  transition: all var(--transition-fast);
  white-space: nowrap;
  flex-shrink: 0;
}

.tab-btn-day {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.tab-btn-date {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  font-family: var(--font-heading);
}

.tab-btn:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--border-medium);
  color: #fff;
}

.tab-btn.active {
  background: var(--grad-primary);
  border-color: transparent;
  color: #070d18;
  box-shadow: 0 4px 18px rgba(0, 210, 255, 0.4);
}

.tab-btn.active .tab-btn-day,
.tab-btn.active .tab-btn-date {
  color: #070d18;
}

.tab-btn.special-day.active {
  background: var(--grad-amber);
  box-shadow: 0 4px 18px rgba(245, 158, 11, 0.4);
}

/* Schedule Pane */
.schedule-pane {
  display: none;
  animation: fadeIn 0.35s ease forwards;
}

.schedule-pane.active {
  display: block;
}

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

.schedule-day-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding: 1.25rem 1.75rem;
  background: rgba(14, 23, 42, 0.9);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  border-bottom: none;
}

.schedule-day-title {
  font-size: 1.4rem;
  color: #fff;
}

.schedule-day-subtitle {
  font-size: 0.9rem;
  color: var(--accent-cyan);
  font-weight: 600;
}

.timeline-list {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.timeline-item {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 1.5rem;
  align-items: center;
  padding: 1.15rem 1.5rem;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.timeline-item:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateX(4px);
}

.timeline-time-block {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text-primary);
  font-family: var(--font-heading);
}

.timeline-time-block i {
  color: var(--accent-cyan);
}

.timeline-content-block {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.timeline-activity {
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
}

.timeline-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  letter-spacing: 0.04em;
}

.tag-lecture {
  background: rgba(0, 210, 255, 0.12);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 210, 255, 0.3);
}

.tag-break {
  background: rgba(148, 163, 184, 0.15);
  color: var(--text-muted);
  border: 1px solid rgba(148, 163, 184, 0.25);
}

.tag-practical {
  background: rgba(245, 158, 11, 0.15);
  color: var(--accent-gold);
  border: 1px solid rgba(245, 158, 11, 0.35);
}

.tag-social {
  background: rgba(16, 185, 129, 0.15);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.35);
}

.tag-poster {
  background: rgba(192, 132, 252, 0.15);
  color: #c084fc;
  border: 1px solid rgba(192, 132, 252, 0.35);
}

/* ==========================================================================
   Poster & Presentation Section
   ========================================================================== */
.poster-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: center;
}

.poster-card {
  background: linear-gradient(145deg, rgba(14, 23, 42, 0.85) 0%, rgba(22, 34, 56, 0.7) 100%);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

.poster-perks {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  margin-top: 1.75rem;
}

.poster-perk-item {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.poster-perk-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: rgba(192, 132, 252, 0.15);
  color: #c084fc;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}

/* ==========================================================================
   Venue & Accommodation Section
   ========================================================================== */
.venue-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
}

.venue-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all var(--transition-normal);
}

.venue-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-highlight);
  box-shadow: var(--shadow-md);
}

.venue-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: rgba(0, 210, 255, 0.12);
  border: 1px solid rgba(0, 210, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 1.6rem;
  margin-bottom: 1.5rem;
}

.venue-icon-wrapper.amber {
  background: rgba(245, 158, 11, 0.12);
  border-color: rgba(245, 158, 11, 0.25);
  color: var(--accent-gold);
}

.venue-card h3 {
  font-size: 1.45rem;
  margin-bottom: 0.75rem;
  color: #fff;
}

.venue-card p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 1.25rem;
}

.venue-card-badge {
  margin-top: auto;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--accent-cyan);
  font-weight: 600;
}

.venue-card-badge.amber {
  color: var(--accent-gold);
}

/* ==========================================================================
   Social Programme Section
   ========================================================================== */
.social-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.social-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
}

.social-card:hover {
  transform: translateY(-5px);
  border-color: rgba(245, 158, 11, 0.4);
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.4);
}

.social-date-badge {
  display: inline-block;
  align-self: flex-start;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  background: rgba(245, 158, 11, 0.12);
  color: var(--accent-gold);
  border: 1px solid rgba(245, 158, 11, 0.3);
  margin-bottom: 1.25rem;
}

.social-card h3 {
  font-size: 1.35rem;
  color: #fff;
  margin-bottom: 0.75rem;
}

.social-card p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==========================================================================
   Lecturers & Organisation Section
   ========================================================================== */
.org-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
}

.org-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
}

.org-card h3 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.org-card h3 i {
  color: var(--accent-cyan);
}

.org-card-content {
  background: rgba(7, 13, 24, 0.5);
  border: 1px dashed var(--border-medium);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  text-align: center;
}

.committee-list {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.committee-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 1rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  transition: all var(--transition-fast);
}

.committee-list li:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(0, 210, 255, 0.3);
}

.committee-list li strong {
  color: #fff;
  font-weight: 600;
}

.committee-list li span {
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 500;
}

.lecturers-banner {
  background: linear-gradient(145deg, rgba(14, 23, 42, 0.8) 0%, rgba(22, 34, 56, 0.6) 100%);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 3rem 2rem;
  text-align: center;
  margin-bottom: 2.5rem;
}

.lecturers-banner h3 {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}

.lecturers-banner p {
  max-width: 680px;
  margin: 0 auto 1.5rem auto;
}

/* ==========================================================================
   Registration & Important Dates
   ========================================================================== */
.dates-reg-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 3rem;
  align-items: start;
}

.reg-card {
  background: linear-gradient(145deg, rgba(14, 23, 42, 0.95) 0%, rgba(22, 34, 56, 0.85) 100%);
  border: 1px solid rgba(0, 210, 255, 0.25);
  border-radius: var(--radius-xl);
  padding: 3rem 2.5rem;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.reg-card::before {
  content: '';
  position: absolute;
  top: -50px;
  right: -50px;
  width: 150px;
  height: 150px;
  background: rgba(0, 210, 255, 0.15);
  border-radius: 50%;
  filter: blur(40px);
}

.reg-card h3 {
  font-size: 1.85rem;
  color: #fff;
  margin-bottom: 1rem;
}

.reg-card-lead {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.6;
}

.inclusions-title {
  font-size: 1.1rem;
  color: #fff;
  font-weight: 700;
  margin-bottom: 1.25rem;
}

.inclusions-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 2.25rem;
}

.inclusion-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.92rem;
  color: var(--text-secondary);
}

.inclusion-item i {
  color: var(--accent-cyan);
}

.dates-single-container {
  max-width: 680px;
  margin: 0 auto;
}

.dates-card {
  background: linear-gradient(145deg, rgba(14, 23, 42, 0.95) 0%, rgba(22, 34, 56, 0.85) 100%);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-xl);
  padding: 3rem 2.5rem;
  box-shadow: var(--shadow-lg);
}

.dates-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1.75rem;
  color: #fff;
}

.dates-timeline {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: relative;
}

.dates-timeline::before {
  content: '';
  position: absolute;
  top: 15px;
  bottom: 15px;
  left: 17px;
  width: 2px;
  background: var(--border-medium);
}

.date-node {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  position: relative;
}

.date-dot {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 2px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 0.85rem;
  flex-shrink: 0;
  z-index: 1;
}

.date-node.highlight .date-dot {
  background: var(--accent-cyan);
  color: #070d18;
  box-shadow: 0 0 15px rgba(0, 210, 255, 0.6);
}

.date-node-content h4 {
  font-size: 1.05rem;
  color: #fff;
  margin-bottom: 0.2rem;
}

.date-node-content p {
  font-size: 0.9rem;
  color: var(--accent-gold);
  font-weight: 600;
}

/* ==========================================================================
   Sponsors & Supporters Section
   ========================================================================== */
.sponsors-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 2rem;
  align-items: center;
}

.sponsor-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2rem 1.5rem;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-normal);
  min-height: 140px;
}

.sponsor-card:hover {
  border-color: rgba(0, 210, 255, 0.4);
  background: var(--bg-card-hover);
  transform: translateY(-4px);
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.4), 0 0 20px rgba(0, 210, 255, 0.15);
}

.sponsor-logo-img {
  max-height: 75px;
  max-width: 85%;
  width: auto;
  height: auto;
  object-fit: contain;
  transition: transform var(--transition-fast);
}

.sponsor-card:hover .sponsor-logo-img {
  transform: scale(1.06);
}

/* ==========================================================================
   Contact & Footer Section
   ========================================================================== */
.contact-section {
  padding-bottom: 3rem;
}

.contact-card {
  background: radial-gradient(circle at 50% 0%, rgba(0, 210, 255, 0.12) 0%, transparent 70%),
              linear-gradient(145deg, #0e172a 0%, #080e1b 100%);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-xl);
  padding: 4rem 3rem;
  text-align: center;
  box-shadow: var(--shadow-lg);
  max-width: 860px;
  margin: 0 auto;
}

.contact-icon {
  width: 70px;
  height: 70px;
  border-radius: var(--radius-full);
  background: rgba(0, 210, 255, 0.12);
  border: 1px solid rgba(0, 210, 255, 0.3);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
}

.contact-card h3 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
}

.contact-card p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2rem auto;
}

.contact-email-box {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.9rem 1.75rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-full);
  font-size: 1.05rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 2rem;
  transition: all var(--transition-fast);
}

.contact-email-box:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
}

.footer {
  border-top: 1px solid var(--border-subtle);
  padding: 3rem 0 2rem 0;
  background: #050810;
}

.footer-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 2rem;
  margin-bottom: 2.5rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.footer-logo-img {
  height: 44px;
  width: auto;
}

.footer-info h4 {
  font-size: 1.05rem;
  color: #fff;
}

.footer-info p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.footer-links a {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

.footer-bottom {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 0.825rem;
  color: var(--text-dim);
}

/* Back to top button */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 46px;
  height: 46px;
  border-radius: var(--radius-full);
  background: rgba(14, 23, 42, 0.9);
  border: 1px solid var(--border-medium);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  z-index: 900;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-md);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--accent-cyan);
  color: #070d18;
  transform: translateY(-3px);
  box-shadow: var(--shadow-glow);
}

/* ==========================================================================
   Responsive Styles
   ========================================================================== */
@media (max-width: 1024px) {
  .about-grid,
  .poster-grid,
  .practical-grid,
  .org-grid,
  .dates-reg-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 320px;
    height: 100vh;
    background: rgba(7, 13, 24, 0.96);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: flex-start;
    padding: 6rem 2.5rem 3rem 2.5rem;
    gap: 1.5rem;
    box-shadow: -10px 0 30px rgba(0, 0, 0, 0.7);
    transition: right var(--transition-normal);
    z-index: 1000;
  }

  .nav-menu.open {
    right: 0;
  }

  .mobile-toggle {
    display: flex;
  }
}

@media (max-width: 768px) {
  .section {
    padding: 4.5rem 0;
  }

  .hero-meta-bar {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    padding: 1.25rem 1.5rem;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }

  .practical-showcase {
    padding: 2.5rem 1.5rem;
  }

  .practical-highlights,
  .inclusions-list {
    grid-template-columns: 1fr;
  }

  .contact-card {
    padding: 3rem 1.5rem;
  }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
  }
}