/* ==========================================================================
   CampusConnect: Study Buddy - Modern 2026 UI System
   ========================================================================== */

:root {
  color-scheme: light;

  --color-primary: #0079c2;
  --color-primary-dark: #005f99;
  --color-primary-light: #e6f3fa;
  --color-secondary: #cad510;
  --color-accent: #df006e;
  --color-success: #10b981;
  --color-success-bg: #ecfdf5;
  --color-warning: #f59e0b;

  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-surface-subtle: #f1f5f9;
  --color-border: #e2e8f0;
  --color-border-hover: #cbd5e1;
  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;
  --color-text-white: #ffffff;

  --font-base: "Roboto", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 14px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 25px -3px rgba(0, 121, 194, 0.12), 0 4px 6px -2px rgba(0, 0, 0, 0.03);
  --transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
}

body {
  font-family: var(--font-base);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.55;
  display: flex;
  flex-direction: column;
}

/* ==========================================================================
   Header & Subpage Navigation
   ========================================================================== */

.service-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  z-index: 50;
  box-shadow: var(--shadow-sm);
}

@media (min-width: 769px) {
  .service-header {
    position: sticky;
    top: 0;
  }
}

.service-header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.service-title-wrap {
  display: flex;
  align-items: center;
  gap: 14px;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  color: var(--color-primary);
  text-decoration: none;
  font-size: 1.2rem;
  font-weight: bold;
  transition: var(--transition);
}

.back-btn:hover {
  background: var(--color-primary-light);
  transform: translateX(-2px);
}

.service-header h1 {
  font-size: 1.3rem;
  margin: 0;
  font-weight: 800;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.service-header h1 span {
  color: var(--color-primary);
}

/* Desktop Global Nav in Study Buddy */
.desktop-nav {
  display: none;
  align-items: center;
  gap: 8px;
}

@media (min-width: 768px) {
  .desktop-nav {
    display: flex;
  }
}

.desktop-nav a {
  text-decoration: none;
  color: var(--color-text-secondary);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 8px 16px;
  border-radius: var(--radius-full);
  transition: var(--transition);
}

.desktop-nav a:hover {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

/* Service Sub-navigation Tabs */
.sub-nav-bar {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.nav-tabs {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
}

.nav-tabs a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 14px 16px;
  color: var(--color-text-secondary);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.92rem;
  white-space: nowrap;
  border-bottom: 3px solid transparent;
  transition: var(--transition);
}

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

.nav-tabs a.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
  font-weight: 700;
}

/* ==========================================================================
   Main Content Layout
   ========================================================================== */

main {
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  padding: 24px 20px 60px 20px;
  flex: 1;
}

/* Modern Hero / Intro Banner */
.intro-banner {
  background: linear-gradient(135deg, #ffffff 0%, #f1f7fc 100%);
  border: 1px solid #d4e7f5;
  padding: 22px 26px;
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.intro-text h2 {
  margin: 0 0 6px 0;
  color: var(--color-primary);
  font-size: 1.35rem;
  font-weight: 800;
}

.intro-text p {
  margin: 0;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  max-width: 700px;
}

/* Campus bar */
.campus-selector-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: 12px 18px;
  border-radius: var(--radius-md);
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
  flex-wrap: wrap;
  gap: 12px;
}

.campus-selector-box label {
  font-weight: 700;
  color: var(--color-text);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 6px;
}

.campus-selector-box select {
  padding: 9px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  font-family: inherit;
  font-size: 0.95rem;
  background-color: var(--color-surface);
  color: var(--color-text);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.campus-selector-box select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(0, 121, 194, 0.15);
}

/* Pulse Section */
.pulse-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.pulse-header h2 {
  margin: 0;
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--color-text);
}

.live-indicator {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: var(--color-success-bg);
  color: var(--color-success);
  font-size: 0.85rem;
  font-weight: 700;
  padding: 5px 12px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(16, 185, 129, 0.25);
}

.live-dot {
  width: 9px;
  height: 9px;
  background-color: var(--color-success);
  border-radius: 50%;
  display: inline-block;
  animation: pulse 1.8s infinite;
}

@keyframes pulse {
  0% {
    transform: scale(0.95);
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
  }
  70% {
    transform: scale(1.1);
    box-shadow: 0 0 0 8px rgba(16, 185, 129, 0);
  }
  100% {
    transform: scale(0.95);
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
  }
}

/* ==========================================================================
   Modern Cards Grid
   ========================================================================== */

.cards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin-bottom: 32px;
}

@media (min-width: 680px) {
  .cards-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition);
  position: relative;
}

.card:hover {
  transform: translateY(-3px);
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
}

.card-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.course-code {
  font-weight: 800;
  color: var(--color-primary);
  font-size: 0.85rem;
  background: var(--color-primary-light);
  padding: 4px 10px;
  border-radius: var(--radius-full);
  letter-spacing: 0.02em;
}

.spots-badge {
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: var(--color-surface-subtle);
  color: var(--color-text-secondary);
}

.spots-badge.available {
  background: var(--color-success-bg);
  color: var(--color-success);
}

.card h3 {
  margin: 0 0 8px 0;
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-text);
}

.card-location {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-text-muted);
  font-size: 0.88rem;
  margin-bottom: 10px;
}

.card-desc {
  font-size: 0.92rem;
  color: var(--color-text-secondary);
  margin-bottom: 16px;
  flex-grow: 1;
  line-height: 1.5;
}

.card-members {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 16px;
  padding-top: 10px;
  border-top: 1px solid var(--color-surface-subtle);
}

.btn-primary {
  display: inline-block;
  background-color: var(--color-primary);
  color: var(--color-text-white);
  padding: 10px 18px;
  text-decoration: none;
  font-weight: 700;
  border-radius: var(--radius-full);
  text-align: center;
  border: none;
  cursor: pointer;
  font-size: 0.92rem;
  transition: var(--transition);
  box-shadow: 0 2px 6px rgba(0, 121, 194, 0.25);
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  box-shadow: 0 4px 10px rgba(0, 121, 194, 0.35);
}

.btn-secondary {
  display: inline-block;
  background-color: var(--color-surface);
  color: var(--color-text);
  padding: 10px 18px;
  text-decoration: none;
  font-weight: 700;
  border-radius: var(--radius-full);
  text-align: center;
  border: 1px solid var(--color-border);
  cursor: pointer;
  font-size: 0.92rem;
  transition: var(--transition);
}

.btn-secondary:hover {
  background-color: var(--color-surface-subtle);
  border-color: var(--color-border-hover);
}

/* Action Callout Box */
.action-box {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  text-align: center;
  margin-top: 20px;
  box-shadow: var(--shadow-sm);
}

.action-box h3 {
  margin-top: 0;
  color: var(--color-text);
  font-size: 1.25rem;
  font-weight: 800;
}

.action-box p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  margin-bottom: 20px;
}

/* ==========================================================================
   Modern Forms
   ========================================================================== */

.form-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--shadow-sm);
  max-width: 700px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--color-text);
  font-size: 0.92rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.95rem;
  background: var(--color-surface);
  color: var(--color-text);
  transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(0, 121, 194, 0.15);
}

.form-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.form-row .form-group {
  flex: 1;
  min-width: 220px;
}

.form-hint {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-top: 4px;
}

/* Search bar */
.search-controls {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: 18px;
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  box-shadow: var(--shadow-sm);
}

.search-controls input,
.search-controls select {
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.95rem;
  transition: var(--transition);
}

.search-controls input:focus,
.search-controls select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(0, 121, 194, 0.15);
}

/* Detail Page */
.detail-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.detail-header {
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 16px;
  margin-bottom: 20px;
}

.detail-meta-list {
  list-style: none;
  padding: 0;
  margin: 0 0 20px 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.detail-meta-list li {
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  padding: 12px 14px;
  border-radius: var(--radius-md);
  font-size: 0.92rem;
}

.detail-meta-list strong {
  display: block;
  color: var(--color-text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 2px;
}

.member-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 14px 0 22px 0;
}

.member-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--color-primary-light);
  border: 1px solid #d4e7f5;
  color: var(--color-primary-dark);
  padding: 7px 14px;
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 600;
}

.member-chip.host {
  background: var(--color-success-bg);
  border-color: #a7f3d0;
  color: var(--color-success);
}

.info-notice {
  background: #f0f7ff;
  border-left: 4px solid var(--color-primary);
  padding: 14px 16px;
  border-radius: 4px;
  font-size: 0.92rem;
  margin: 18px 0;
  color: var(--color-text);
}

/* Footer System (Always in normal document flow at the end of the page) */
.site-footer {
  margin-top: auto;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: 28px 20px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.site-footer-links {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.site-footer-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

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

.mobile-nav-bar {
  display: none !important;
}