/* ==========================================================================
   BAU Knowledge Hub - Modern, Premium Academic Platform Stylesheet (Phase 2)
   Bangladesh Agricultural University (BAU), Mymensingh-2202
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

:root {
  /* Color Palette - Emerald Academic & Slate */
  --primary: #059669;
  --primary-hover: #047857;
  --primary-light: #ecfdf5;
  --primary-border: #a7f3d0;
  --primary-glow: rgba(16, 185, 129, 0.25);
  
  --accent: #10b981;
  --accent-blue: #2563eb;
  --accent-amber: #d97706;
  --accent-purple: #7c3aed;
  --accent-rose: #e11d48;
  --accent-gold: #f59e0b;

  /* Neutrals (Light Mode) */
  --bg: #f8fafc;
  --bg-subtle: #f1f5f9;
  --surface: #ffffff;
  --surface-hover: #f8fafc;
  --surface-border: #e2e8f0;
  --surface-glass: rgba(255, 255, 255, 0.9);

  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-subtle: #94a3b8;
  --text-inverse: #ffffff;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  --shadow-glow: 0 0 20px rgba(16, 185, 129, 0.2);

  /* Radius & Transitions */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
}

[data-theme="dark"] {
  --bg: #0b1320;
  --bg-subtle: #111e33;
  --surface: #152238;
  --surface-hover: #1b2d4b;
  --surface-border: #243b5e;
  --surface-glass: rgba(21, 34, 56, 0.92);

  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-subtle: #64748b;

  --primary-light: rgba(5, 150, 105, 0.18);
  --primary-border: rgba(16, 185, 129, 0.35);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 24px rgba(0, 0, 0, 0.5);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.55;
  transition: background-color var(--transition-base), color var(--transition-base);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

a:hover {
  color: var(--primary-hover);
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* ==========================================================================
   Layout Containers
   ========================================================================== */
.container {
  width: 100%;
  max-width: 1360px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--surface-border);
  transition: all var(--transition-fast);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-main);
  flex-shrink: 0;
}

.brand-emblem {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, #059669, #10b981);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  color: white;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.35);
  position: relative;
  overflow: hidden;
}

.brand-emblem svg {
  width: 32px;
  height: 32px;
  fill: white;
}

.brand-text h1 {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(90deg, var(--text-main), var(--primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: flex;
  align-items: center;
  gap: 6px;
}

.brand-text p {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
}

.nav-links::-webkit-scrollbar {
  display: none;
}

.nav-item {
  padding: 8px 12px;
  border-radius: var(--radius-md);
  color: var(--text-muted);
  font-size: 0.86rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  background: transparent;
  white-space: nowrap;
}

.nav-item:hover, .nav-item.active {
  color: var(--primary);
  background: var(--primary-light);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

/* User Profile Badge in Nav */
.nav-user-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px 5px 6px;
  border-radius: var(--radius-full);
  background: var(--surface);
  border: 1px solid var(--surface-border);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.nav-user-badge:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.nav-avatar {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full);
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
}

.nav-user-info {
  display: flex;
  flex-direction: column;
  text-align: left;
}

.nav-user-name {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.1;
}

.nav-user-pts {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--primary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 8px 16px;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 2px 8px rgba(5, 150, 105, 0.25);
}

.btn-primary:hover {
  background: var(--primary-hover);
  color: white;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(5, 150, 105, 0.35);
}

.btn-outline {
  background: transparent;
  border-color: var(--surface-border);
  color: var(--text-main);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-light);
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--surface-border);
  background: var(--surface);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-icon:hover {
  color: var(--primary);
  border-color: var(--primary-border);
  background: var(--primary-light);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
  padding: 3rem 0 2.5rem;
  background: radial-gradient(circle at 50% 0%, var(--primary-light) 0%, transparent 70%);
  border-bottom: 1px solid var(--surface-border);
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  background: var(--primary-light);
  border: 1px solid var(--primary-border);
  color: var(--primary);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: 2.6rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--text-main);
  margin-bottom: 0.85rem;
}

.hero-title span {
  color: var(--primary);
  background: linear-gradient(135deg, #059669, #10b981);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 2rem;
}

.search-box-wrapper {
  max-width: 760px;
  margin: 0 auto;
  position: relative;
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--surface);
  border: 2px solid var(--surface-border);
  border-radius: var(--radius-xl);
  padding: 6px 12px 6px 20px;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-fast);
}

.search-box:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-glow), var(--shadow-xl);
}

.search-icon {
  font-size: 1.2rem;
  color: var(--text-subtle);
  margin-right: 12px;
}

.search-input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  color: var(--text-main);
  font-size: 1rem;
  font-weight: 500;
}

.search-input::placeholder {
  color: var(--text-subtle);
}

.search-quick-tags {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 1rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.quick-tag {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.quick-tag:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-light);
}

/* ==========================================================================
   Faculty Selector Grid
   ========================================================================== */
.section {
  padding: 2.5rem 0;
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.section-title h2 {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.section-title p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.faculty-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.faculty-card {
  background: var(--surface);
  border: 1.5px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  position: relative;
  overflow: hidden;
}

.faculty-card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.faculty-card.active {
  border-color: var(--primary);
  background: var(--primary-light);
  box-shadow: 0 0 0 1px var(--primary);
}

.faculty-icon {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}

.faculty-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.4rem;
  line-height: 1.3;
}

.faculty-meta {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: auto;
}

/* ==========================================================================
   Level - Semester Bar
   ========================================================================== */
.level-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  overflow-x: auto;
  padding: 6px 2px 12px;
  scrollbar-width: thin;
}

.level-pill {
  padding: 8px 16px;
  border-radius: var(--radius-full);
  background: var(--surface);
  border: 1px solid var(--surface-border);
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.level-pill:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.level-pill.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
  box-shadow: 0 2px 8px rgba(5, 150, 105, 0.3);
}

/* ==========================================================================
   Course Hub Layout & Resource Tabs
   ========================================================================== */
.main-layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 1.5rem;
  align-items: start;
}

.sidebar {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  position: sticky;
  top: 90px;
}

.sidebar-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.course-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 600px;
  overflow-y: auto;
  padding-right: 4px;
}

.course-item {
  padding: 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--surface-border);
  background: var(--bg);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.course-item:hover {
  border-color: var(--primary-border);
  background: var(--surface);
  transform: translateX(2px);
}

.course-item.active {
  border-color: var(--primary);
  background: var(--primary-light);
}

.course-item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 4px;
}

.course-code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--primary);
}

.course-credits {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 6px;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
}

.course-title {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.35;
}

.content-area {
  min-width: 0;
}

.course-banner {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.course-banner-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}

.course-banner-code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary);
  background: var(--primary-light);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--primary-border);
  display: inline-block;
  margin-bottom: 6px;
}

.course-banner h2 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

.course-banner-instructor {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 6px;
}

.course-banner-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-top: 0.75rem;
}

.resource-tabs {
  display: flex;
  align-items: center;
  gap: 6px;
  border-bottom: 2px solid var(--surface-border);
  margin-bottom: 1.5rem;
  overflow-x: auto;
  scrollbar-width: thin;
}

.res-tab {
  padding: 10px 16px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
  border: none;
  background: transparent;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-fast);
}

.res-tab:hover {
  color: var(--text-main);
}

.res-tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.res-badge {
  font-size: 0.72rem;
  padding: 1px 6px;
  border-radius: var(--radius-full);
  background: var(--bg-subtle);
  color: var(--text-muted);
}

.res-tab.active .res-badge {
  background: var(--primary-light);
  color: var(--primary);
}

.resource-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.resource-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  transition: all var(--transition-fast);
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
}

.resource-card:hover {
  border-color: var(--primary-border);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.res-left {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  flex: 1;
}

.file-type-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--bg-subtle);
  border: 1px solid var(--surface-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-weight: 800;
  font-family: 'JetBrains Mono', monospace;
  color: var(--primary);
  flex-shrink: 0;
}

.file-type-icon.pdf { color: #e11d48; background: #ffe4e6; border-color: #fecdd3; }
.file-type-icon.pptx { color: #d97706; background: #fef3c7; border-color: #fde68a; }

.res-info h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 4px;
  line-height: 1.4;
}

.res-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.res-meta {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 0.78rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.badge-tag {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--primary-light);
  color: var(--primary);
  border: 1px solid var(--primary-border);
}

.badge-topper { background: #fef3c7; color: #b45309; border-color: #fde68a; }
.badge-cr { background: #dbeafe; color: #1d4ed8; border-color: #bfdbfe; }
.badge-gold { background: #fef9c3; color: #a16207; border-color: #fef08a; }

.res-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

/* ==========================================================================
   AI Summary Banner & Box
   ========================================================================== */
.ai-summary-card {
  background: linear-gradient(135deg, rgba(5, 150, 105, 0.05), rgba(37, 99, 235, 0.05));
  border: 1.5px solid var(--primary-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
}

.ai-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #059669, #2563eb);
  color: white;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

.ai-summary-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.ai-summary-header h3 {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
}

.ai-summary-body {
  font-size: 0.9rem;
  color: var(--text-main);
  line-height: 1.6;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  margin-bottom: 1rem;
}

.ai-formula-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin: 1rem 0;
}

.ai-formula-box {
  background: var(--bg);
  border-left: 3px solid var(--primary);
  padding: 8px 12px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.82rem;
  color: var(--text-main);
}

/* ==========================================================================
   🏆 1. Top Contributors & Leaderboard Podium
   ========================================================================== */
.leaderboard-podium {
  display: grid;
  grid-template-columns: 1fr 1.15fr 1fr;
  gap: 1.25rem;
  align-items: end;
  margin-bottom: 2.5rem;
}

.podium-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-xl);
  padding: 1.5rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: all var(--transition-fast);
}

.podium-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.podium-rank-1 {
  border: 2px solid var(--accent-gold);
  background: linear-gradient(180deg, rgba(245, 158, 11, 0.08), var(--surface));
  padding: 2rem 1.5rem;
}

.podium-crown {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.podium-avatar {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-full);
  margin: 0 auto 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 800;
  color: white;
  box-shadow: var(--shadow-md);
}

.podium-name {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
}

.podium-pts {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--primary);
  margin: 0.5rem 0;
}

.leaderboard-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.leaderboard-table th, .leaderboard-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--surface-border);
  font-size: 0.9rem;
}

.leaderboard-table th {
  background: var(--bg-subtle);
  font-weight: 700;
  color: var(--text-muted);
}

/* ==========================================================================
   💡 3. Seniors' Advice Cards
   ========================================================================== */
.advice-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(380px, 1fr));
  gap: 1.5rem;
}

.advice-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
}

.advice-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.advice-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}

.advice-header h3 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
  line-height: 1.35;
}

.advice-author {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--surface-border);
}

.advice-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 0.88rem;
  color: var(--text-main);
  flex: 1;
}

.advice-bullets li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.advice-bullets li::before {
  content: "💡";
  font-size: 0.85rem;
  flex-shrink: 0;
  margin-top: 2px;
}

/* ==========================================================================
   🤝 4. 1-on-1 Mentorship & Counselling Cards
   ========================================================================== */
.mentor-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.mentor-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
}

.mentor-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.mentor-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 1rem;
}

.mentor-avatar {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  font-weight: 800;
  color: white;
  flex-shrink: 0;
}

.mentor-info h3 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
}

.mentor-rating {
  font-size: 0.82rem;
  color: var(--accent-amber);
  font-weight: 700;
  margin-top: 2px;
}

.mentor-specs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0.75rem 0 1.25rem;
}

.spec-pill {
  font-size: 0.75rem;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  background: var(--bg-subtle);
  color: var(--text-muted);
}

/* ==========================================================================
   🎪 5. BAU Clubs & Events Hub
   ========================================================================== */
.club-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.club-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
}

.club-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.club-top {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 0.75rem;
}

.club-icon {
  font-size: 2rem;
}

.club-title h3 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
}

.club-category {
  font-size: 0.78rem;
  color: var(--primary);
  font-weight: 600;
}

.event-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.event-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
  transition: all var(--transition-fast);
}

.event-card:hover {
  border-color: var(--primary-border);
  box-shadow: var(--shadow-sm);
}

.event-date-box {
  background: var(--primary-light);
  border: 1px solid var(--primary-border);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  text-align: center;
  flex-shrink: 0;
}

.event-month {
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--primary);
}

.event-day {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary-hover);
  line-height: 1;
}

/* ==========================================================================
   📜 6. Research Publications & Scholarship Spotlight
   ========================================================================== */
.pub-grid, .sch-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(380px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2.5rem;
}

.pub-card, .sch-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
}

.pub-card:hover, .sch-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.pub-title h3, .sch-title h3 {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 6px;
  line-height: 1.4;
}

.pub-journal {
  font-size: 0.82rem;
  color: var(--primary);
  font-weight: 700;
  margin-bottom: 8px;
}

/* ==========================================================================
   Gratitude & Tip Modal Components
   ========================================================================== */
.tip-preset-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  margin: 1rem 0;
}

.tip-preset-btn {
  padding: 10px 8px;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--surface-border);
  background: var(--bg);
  font-weight: 700;
  font-size: 0.88rem;
  color: var(--text-main);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: center;
}

.tip-preset-btn:hover, .tip-preset-btn.active {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}

.payment-method-selector {
  display: flex;
  gap: 10px;
  margin-bottom: 1rem;
}

.pay-radio {
  flex: 1;
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  padding: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 600;
}

.pay-radio.active {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}

/* ==========================================================================
   Modals & Overlays
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.65);
  backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 1.5rem;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-xl);
  max-width: 800px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  transform: scale(0.96);
  transition: transform var(--transition-base);
}

.modal-overlay.active .modal-content {
  transform: scale(1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--surface-border);
}

.modal-header h3 {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.modal-body {
  padding: 1.5rem;
}

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  padding: 1.25rem 1.5rem;
  border-top: 1px solid var(--surface-border);
  background: var(--bg-subtle);
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 10px 14px;
  border-radius: var(--radius-md);
  border: 1px solid var(--surface-border);
  background: var(--bg);
  color: var(--text-main);
  font-size: 0.9rem;
  outline: none;
  transition: border-color var(--transition-fast);
}

.form-control:focus {
  border-color: var(--primary);
  background: var(--surface);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  background: var(--surface);
  border: 1px solid var(--primary-border);
  border-left: 4px solid var(--primary);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  box-shadow: var(--shadow-lg);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideIn 0.25s ease forwards;
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* Footer */
.footer {
  margin-top: auto;
  background: var(--surface);
  border-top: 1px solid var(--surface-border);
  padding: 2.5rem 0 1.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-brand h4 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 6px;
}

.footer-brand p {
  font-size: 0.85rem;
  color: var(--text-muted);
  max-width: 400px;
}

.footer-col h5 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.85rem;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  border-top: 1px solid var(--surface-border);
  padding-top: 1.25rem;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 1024px) {
  .main-layout { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .leaderboard-podium { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .hero-title { font-size: 1.85rem; }
  .faculty-grid { grid-template-columns: repeat(2, 1fr); }
  .advice-grid, .mentor-grid, .club-grid, .pub-grid, .sch-grid { grid-template-columns: 1fr; }
  .ai-formula-grid { grid-template-columns: 1fr; }
}

/* ==========================================================================
   Auth & Login / Sign Up Modal Styles
   ========================================================================== */
.auth-tabs {
  display: flex;
  border-bottom: 2px solid var(--surface-border);
  margin-bottom: 1.5rem;
}

.auth-tab {
  flex: 1;
  text-align: center;
  padding: 12px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-muted);
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.auth-tab:hover {
  color: var(--text-main);
}

.auth-tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.auth-quick-login-box {
  background: var(--bg);
  border: 1px dashed var(--primary-border);
  border-radius: var(--radius-md);
  padding: 12px;
  margin-top: 1rem;
  text-align: center;
}

.auth-quick-login-box p {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.demo-account-chips {
  display: flex;
  justify-content: center;
  gap: 6px;
  flex-wrap: wrap;
}

.demo-chip {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: var(--surface);
  border: 1px solid var(--surface-border);
  color: var(--primary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.demo-chip:hover {
  background: var(--primary-light);
  border-color: var(--primary);
}