/* ============================================
   Athena Alumni Network — Design System
   Version 1.0 | June 2026
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Brand Colors */
  --color-navy: #1B2A6B;
  --color-navy-dark: #0F1A45;
  --color-navy-light: #2A3D8F;
  --color-gold: #F5A623;
  --color-gold-light: #FFC85C;
  --color-white: #FFFFFF;
  --color-off-white: #F8F9FC;
  --color-gray-50: #F5F6FA;
  --color-gray-100: #E8EAF0;
  --color-gray-200: #D1D5E0;
  --color-gray-300: #A0A8BE;
  --color-gray-400: #6B7694;
  --color-gray-500: #4A5568;
  --color-gray-700: #2D3748;
  --color-gray-900: #1A202C;
  --color-green: #2ECC71;
  --color-green-light: #E8FAF0;
  --color-red: #E74C3C;
  --color-red-light: #FDECEB;
  --color-blue-light: #EBF5FF;

  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-display: 'Inter', sans-serif;

  /* Spacing scale */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 800px;
  --header-height: 72px;
  --border-radius: 8px;
  --border-radius-lg: 12px;
  --border-radius-xl: 16px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(27, 42, 107, 0.08);
  --shadow-md: 0 4px 12px rgba(27, 42, 107, 0.1);
  --shadow-lg: 0 8px 24px rgba(27, 42, 107, 0.12);
  --shadow-xl: 0 16px 48px rgba(27, 42, 107, 0.15);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-primary);
  color: var(--color-gray-700);
  background: var(--color-white);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover {
  color: var(--color-navy-light);
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 2px;
}

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  color: var(--color-navy);
  line-height: 1.25;
  font-weight: 700;
}

h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.15rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.125rem; }

p {
  margin-bottom: var(--space-md);
}

p:last-child {
  margin-bottom: 0;
}

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container--narrow {
  max-width: var(--container-narrow);
}

main {
  flex: 1;
}

.section {
  padding: var(--space-3xl) 0;
}

.section--gray {
  background: var(--color-off-white);
}

.section--navy {
  background: var(--color-navy);
  color: var(--color-white);
}

.section--navy h2,
.section--navy h3,
.section--navy h4 {
  color: var(--color-white);
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section__subtitle {
  color: var(--color-gray-400);
  font-size: 1.05rem;
  margin-top: var(--space-sm);
}

/* --- Grid --- */
.grid {
  display: grid;
  gap: var(--space-lg);
}

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

/* --- Header --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-white);
  border-bottom: 1px solid var(--color-gray-100);
  height: var(--header-height);
  box-shadow: var(--shadow-sm);
}

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

.site-header__brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--color-navy);
  text-decoration: none;
}

.site-header__brand img {
  height: 40px;
  width: auto;
}

.site-header__brand span {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.site-header__brand .brand-sub {
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--color-gold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Main nav */
.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.main-nav a {
  padding: var(--space-sm) var(--space-md);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-gray-500);
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--color-navy);
  background: var(--color-gray-50);
}

.main-nav a.active {
  font-weight: 600;
}

/* Header CTAs */
.header-cta {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
  color: var(--color-navy);
}

.menu-toggle svg {
  width: 24px;
  height: 24px;
}

/* Mobile nav */
@media (max-width: 1024px) {
  .menu-toggle {
    display: block;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-white);
    flex-direction: column;
    padding: var(--space-md);
    border-bottom: 1px solid var(--color-gray-100);
    box-shadow: var(--shadow-lg);
    gap: 0;
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav a {
    padding: var(--space-md);
    width: 100%;
    border-radius: 0;
  }

  .header-cta {
    display: none;
  }

  .header-cta.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: calc(var(--header-height) + 1px);
    right: 0;
    left: 0;
    background: var(--color-white);
    padding: var(--space-md);
    z-index: 99;
  }
}

/* --- Footer --- */
.site-footer {
  background: var(--color-navy-dark);
  color: var(--color-gray-200);
  padding: var(--space-3xl) 0 var(--space-xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--color-gray-300);
  margin-top: var(--space-md);
}

.footer-col h4 {
  color: var(--color-white);
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: var(--space-md);
}

.footer-col a {
  display: block;
  color: var(--color-gray-300);
  font-size: 0.88rem;
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.82rem;
  color: var(--color-gray-400);
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-social {
  display: flex;
  gap: var(--space-md);
}

.footer-social a {
  color: var(--color-gray-300);
  transition: color var(--transition-fast);
}

.footer-social a:hover {
  color: var(--color-gold);
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.625rem 1.25rem;
  font-family: var(--font-primary);
  font-size: 0.9rem;
  font-weight: 600;
  border: 2px solid transparent;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

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

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

.btn--secondary {
  background: transparent;
  color: var(--color-navy);
  border-color: var(--color-navy);
}

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

.btn--gold {
  background: var(--color-gold);
  color: var(--color-navy-dark);
  border-color: var(--color-gold);
}

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

.btn--white {
  background: var(--color-white);
  color: var(--color-navy);
  border-color: var(--color-white);
}

.btn--white:hover {
  background: var(--color-gray-50);
}

.btn--sm {
  padding: 0.4rem 0.9rem;
  font-size: 0.82rem;
}

.btn--lg {
  padding: 0.8rem 1.75rem;
  font-size: 1rem;
}

.btn--block {
  width: 100%;
}

.btn:disabled,
.btn.loading {
  opacity: 0.6;
  cursor: not-allowed;
}

/* --- Cards --- */
.card {
  background: var(--color-white);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--color-gray-100);
  overflow: hidden;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

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

.card__img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card__body {
  padding: var(--space-lg);
}

.card__title {
  font-size: 1.1rem;
  margin-bottom: var(--space-sm);
}

.card__meta {
  font-size: 0.82rem;
  color: var(--color-gray-400);
  margin-bottom: var(--space-sm);
}

.card__text {
  font-size: 0.92rem;
  color: var(--color-gray-500);
}

/* --- Badge / Tag --- */
.badge {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 100px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.badge--navy { background: var(--color-navy); color: var(--color-white); }
.badge--gold { background: var(--color-gold); color: var(--color-navy-dark); }
.badge--green { background: var(--color-green-light); color: #1a7a42; }
.badge--red { background: var(--color-red-light); color: var(--color-red); }
.badge--gray { background: var(--color-gray-100); color: var(--color-gray-500); }

/* --- Forms --- */
.form-group {
  margin-bottom: var(--space-lg);
}

.form-group label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-gray-700);
  margin-bottom: var(--space-xs);
}

.form-group .hint {
  font-size: 0.78rem;
  color: var(--color-gray-400);
  margin-top: var(--space-xs);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.65rem 0.85rem;
  font-family: var(--font-primary);
  font-size: 0.92rem;
  color: var(--color-gray-700);
  background: var(--color-white);
  border: 1.5px solid var(--color-gray-200);
  border-radius: var(--border-radius);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--color-navy);
  box-shadow: 0 0 0 3px rgba(27, 42, 107, 0.1);
  outline: none;
}

.form-input.error,
.form-select.error,
.form-textarea.error {
  border-color: var(--color-red);
}

.form-error {
  font-size: 0.78rem;
  color: var(--color-red);
  margin-top: var(--space-xs);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

.form-checkbox {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  font-size: 0.88rem;
  cursor: pointer;
}

.form-checkbox input[type="checkbox"] {
  margin-top: 3px;
  accent-color: var(--color-navy);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

@media (max-width: 600px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

/* --- Multi-step Form --- */
.step-indicator {
  display: flex;
  justify-content: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-2xl);
}

.step-indicator__step {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.82rem;
  color: var(--color-gray-300);
  font-weight: 500;
}

.step-indicator__step.active {
  color: var(--color-navy);
  font-weight: 600;
}

.step-indicator__step.completed {
  color: var(--color-green);
}

.step-indicator__num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.78rem;
  font-weight: 700;
  background: var(--color-gray-100);
  color: var(--color-gray-400);
}

.step-indicator__step.active .step-indicator__num {
  background: var(--color-navy);
  color: var(--color-white);
}

.step-indicator__step.completed .step-indicator__num {
  background: var(--color-green);
  color: var(--color-white);
}

.step-indicator__line {
  width: 40px;
  height: 2px;
  background: var(--color-gray-200);
  align-self: center;
}

.step-indicator__step.completed + .step-indicator__line {
  background: var(--color-green);
}

.form-step {
  display: none;
}

.form-step.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

.form-actions {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin-top: var(--space-xl);
}

/* --- Stats Bar --- */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-lg);
  text-align: center;
  padding: var(--space-xl) 0;
}

.stat-item__number {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 800;
  color: var(--color-navy);
  line-height: 1;
}

.stat-item__label {
  font-size: 0.82rem;
  color: var(--color-gray-400);
  margin-top: var(--space-xs);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* --- Hero --- */
.hero {
  position: relative;
  background: linear-gradient(135deg, var(--color-navy) 0%, var(--color-navy-dark) 100%);
  color: var(--color-white);
  padding: var(--space-4xl) 0;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 60%;
  height: 200%;
  background: radial-gradient(ellipse, rgba(245, 166, 35, 0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero__content {
  position: relative;
  max-width: 640px;
}

.hero__tagline {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-gold);
  margin-bottom: var(--space-md);
  font-weight: 600;
}

.hero h1 {
  color: var(--color-white);
  margin-bottom: var(--space-lg);
}

.hero__text {
  font-size: 1.1rem;
  color: var(--color-gray-200);
  margin-bottom: var(--space-xl);
  line-height: 1.7;
}

.hero__actions {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
}

/* --- Page Header (non-hero pages) --- */
.page-header {
  background: var(--color-off-white);
  padding: var(--space-2xl) 0;
  border-bottom: 1px solid var(--color-gray-100);
}

.page-header h1 {
  margin-bottom: var(--space-sm);
}

.page-header p {
  color: var(--color-gray-400);
  font-size: 1.05rem;
}

/* Breadcrumb */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 0.82rem;
  color: var(--color-gray-400);
  margin-bottom: var(--space-md);
}

.breadcrumb a {
  color: var(--color-gray-400);
}

.breadcrumb a:hover {
  color: var(--color-navy);
}

.breadcrumb__sep {
  color: var(--color-gray-300);
}

/* --- Toast / Notification --- */
.toast-container {
  position: fixed;
  top: calc(var(--header-height) + var(--space-md));
  right: var(--space-md);
  z-index: 200;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.toast {
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--border-radius);
  font-size: 0.9rem;
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  animation: slideIn 0.3s ease;
  max-width: 380px;
}

.toast--success { background: var(--color-green); color: var(--color-white); }
.toast--error { background: var(--color-red); color: var(--color-white); }
.toast--info { background: var(--color-navy); color: var(--color-white); }

/* --- Spinner --- */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2.5px solid var(--color-gray-200);
  border-top-color: var(--color-navy);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.spinner--lg {
  width: 40px;
  height: 40px;
  border-width: 3px;
}

.loading-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-3xl);
  color: var(--color-gray-400);
  gap: var(--space-md);
}

/* --- Empty State --- */
.empty-state {
  text-align: center;
  padding: var(--space-3xl) var(--space-lg);
  color: var(--color-gray-400);
}

.empty-state__icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
  opacity: 0.5;
}

.empty-state__title {
  font-size: 1.15rem;
  color: var(--color-gray-500);
  margin-bottom: var(--space-sm);
}

/* --- Tabs --- */
.tabs {
  display: flex;
  border-bottom: 2px solid var(--color-gray-100);
  gap: 0;
  margin-bottom: var(--space-xl);
  overflow-x: auto;
}

.tab-btn {
  padding: var(--space-md) var(--space-lg);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  font-family: var(--font-primary);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-gray-400);
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tab-btn:hover {
  color: var(--color-navy);
}

.tab-btn.active {
  color: var(--color-navy);
  border-bottom-color: var(--color-navy);
  font-weight: 600;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

/* --- Search / Filter bar --- */
.search-bar {
  display: flex;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
}

.search-bar input {
  flex: 1;
  min-width: 200px;
}

.filter-group {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.filter-chip {
  padding: 0.35rem 0.85rem;
  font-size: 0.82rem;
  font-weight: 500;
  border: 1.5px solid var(--color-gray-200);
  border-radius: 100px;
  background: var(--color-white);
  color: var(--color-gray-500);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-chip:hover,
.filter-chip.active {
  border-color: var(--color-navy);
  color: var(--color-navy);
  background: var(--color-blue-light);
}

/* --- Avatar --- */
.avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--color-gray-100);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--color-navy);
  font-size: 1rem;
  flex-shrink: 0;
}

.avatar--sm { width: 36px; height: 36px; font-size: 0.82rem; }
.avatar--lg { width: 72px; height: 72px; font-size: 1.5rem; }
.avatar--xl { width: 96px; height: 96px; font-size: 2rem; }

/* --- Admin Table --- */
.admin-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.admin-table th {
  text-align: left;
  padding: var(--space-md);
  background: var(--color-gray-50);
  color: var(--color-gray-500);
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border-bottom: 2px solid var(--color-gray-100);
}

.admin-table td {
  padding: var(--space-md);
  border-bottom: 1px solid var(--color-gray-100);
  vertical-align: middle;
}

.admin-table tr:hover td {
  background: var(--color-gray-50);
}

/* --- Modal --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 300;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

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

.modal {
  background: var(--color-white);
  border-radius: var(--border-radius-xl);
  max-width: 560px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  padding: var(--space-xl);
  box-shadow: var(--shadow-xl);
  transform: translateY(20px);
  transition: transform var(--transition-base);
}

.modal-overlay.open .modal {
  transform: translateY(0);
}

.modal__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-lg);
}

.modal__close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-gray-400);
  padding: var(--space-xs);
}

/* --- Animations --- */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(40px); }
  to { opacity: 1; transform: translateX(0); }
}

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

/* --- Utilities --- */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-gold { color: var(--color-gold); }
.text-navy { color: var(--color-navy); }
.text-muted { color: var(--color-gray-400); }
.text-sm { font-size: 0.85rem; }
.text-xs { font-size: 0.78rem; }
.fw-600 { font-weight: 600; }
.fw-700 { font-weight: 700; }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  border: 0;
}
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

/* --- Auth UI: Header greeting & buttons --- */
.user-greeting {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-navy);
  white-space: nowrap;
}

.btn--outline {
  background: transparent;
  color: var(--color-navy);
  border-color: var(--color-gray-200);
}

.btn--outline:hover {
  background: var(--color-gray-50);
  border-color: var(--color-navy);
  color: var(--color-navy);
}

.btn--danger {
  background: var(--color-red);
  color: var(--color-white);
  border-color: var(--color-red);
}

.btn--danger:hover {
  background: #c0392b;
  border-color: #c0392b;
  color: var(--color-white);
}

/* --- Alumni Photo Marquee --- */
.alumni-marquee {
  overflow: hidden;
  padding-bottom: var(--space-2xl);
}

.marquee-wrapper {
  overflow: hidden;
  position: relative;
  width: 100%;
}

.marquee-wrapper::before,
.marquee-wrapper::after {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  width: 80px;
  z-index: 2;
  pointer-events: none;
}

.marquee-wrapper::before {
  left: 0;
  background: linear-gradient(to right, var(--color-white), transparent);
}

.marquee-wrapper::after {
  right: 0;
  background: linear-gradient(to left, var(--color-white), transparent);
}

.marquee-track {
  display: flex;
  gap: var(--space-lg);
  width: max-content;
  padding: var(--space-sm) 0;
}

.marquee-track--left {
  animation: marquee-scroll-left 30s linear infinite;
}

.marquee-track--right {
  animation: marquee-scroll-right 35s linear infinite;
}

@keyframes marquee-scroll-left {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

@keyframes marquee-scroll-right {
  0% { transform: translateX(-50%); }
  100% { transform: translateX(0); }
}

/* Pause on hover */
.marquee-wrapper:hover .marquee-track {
  animation-play-state: paused;
}

/* Individual avatar */
.alumni-avatar {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
  cursor: pointer;
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.alumni-avatar:hover {
  transform: scale(1.12);
}

.alumni-avatar__initials {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--avatar-bg, var(--color-navy));
  color: var(--color-white);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast);
}

.alumni-avatar:hover .alumni-avatar__initials {
  box-shadow: var(--shadow-md);
}

.alumni-avatar__info {
  font-size: 0.7rem;
  color: var(--color-gray-400);
  font-weight: 500;
}

/* --- Login Prompt Modal --- */
.login-prompt-modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 400;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

.login-prompt-modal.open {
  opacity: 1;
  visibility: visible;
}

.login-prompt-modal__content {
  background: var(--color-white);
  border-radius: var(--border-radius-xl);
  max-width: 420px;
  width: 100%;
  padding: var(--space-2xl);
  text-align: center;
  box-shadow: var(--shadow-xl);
  transform: translateY(20px) scale(0.95);
  transition: transform var(--transition-base);
  position: relative;
}

.login-prompt-modal.open .login-prompt-modal__content {
  transform: translateY(0) scale(1);
}

.login-prompt-modal__close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-gray-400);
  line-height: 1;
  padding: var(--space-xs);
}

.login-prompt-modal__close:hover {
  color: var(--color-gray-700);
}

.login-prompt-modal__icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
}

.login-prompt-modal__content h3 {
  margin-bottom: var(--space-sm);
}

.login-prompt-modal__content p {
  color: var(--color-gray-500);
  font-size: 0.92rem;
  margin-bottom: var(--space-xl);
}

.login-prompt-modal__actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* --- Responsive: Marquee & Auth --- */
@media (max-width: 768px) {
  .alumni-avatar__initials {
    width: 48px;
    height: 48px;
    font-size: 0.9rem;
  }

  .marquee-wrapper::before,
  .marquee-wrapper::after {
    width: 40px;
  }

  .user-greeting {
    display: none;
  }

  .login-prompt-modal__content {
    padding: var(--space-xl);
  }
}

@media (max-width: 480px) {
  .alumni-avatar__initials {
    width: 42px;
    height: 42px;
    font-size: 0.8rem;
  }

  .marquee-track {
    gap: var(--space-md);
  }

  .login-prompt-modal__actions {
    flex-direction: column;
  }

  .login-prompt-modal__actions .btn {
    width: 100%;
  }
}

/* --- Branch colors --- */
.branch--chidambaram { --branch-color: #1B6B3A; }
.branch--chengalpattu { --branch-color: #6B1B5A; }
.branch--chennai { --branch-color: #1B4A6B; }