/* =====================================================
   index.css — AI Builders LMS (Coursera-style UI)
   Fonts: Source Serif 4 + DM Sans
===================================================== */

/* ── Reset ── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'DM Sans', -apple-system, sans-serif;
  background: #fff;
  color: #1f1f1f;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }

/* ── Variables ── */
:root {
  --blue:       #0056D2;
  --blue-dark:  #003B8E;
  --blue-light: #EBF2FF;
  --text:       #1f1f1f;
  --text-2:     #5f5f5f;
  --text-3:     #8f8f8f;
  --border:     #E0E0E0;
  --bg-gray:    #F7F7F7;
  --radius:     8px;
  --radius-lg:  16px;
  --shadow:     0 2px 12px rgba(0,0,0,0.08);
  --shadow-md:  0 4px 24px rgba(0,0,0,0.12);
}

/* ── Container ── */
.container { max-width: 1440px; margin: 0 auto; padding: 0 48px; }
.tc { text-align: center; }

/* =====================================================
   AUDIENCE BAR
===================================================== */
.audience-bar {
  background: #1f1f1f;
  border-bottom: 1px solid #333;
}
.audience-inner {
  max-width: 1440px; margin: 0 auto; padding: 0 48px;
  display: flex; gap: 0;
}
.aud-link {
  display: block;
  padding: 10px 20px;
  font-size: 13px; font-weight: 500;
  color: rgba(255,255,255,0.7);
  border-bottom: 2px solid transparent;
  transition: all 0.2s;
}
.aud-link:hover { color: #fff; }
.aud-link.active { color: #fff; border-bottom-color: #fff; }

/* =====================================================
   NAVBAR
===================================================== */
.navbar {
  position: sticky; top: 0; z-index: 1000;
  background: #fff;
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.25s;
}
.navbar.scrolled { box-shadow: 0 2px 16px rgba(0,0,0,0.1); }
.nav-inner {
  max-width: 1440px; margin: 0 auto; padding: 0 48px;
  height: 60px;
  display: flex; align-items: center; gap: 24px;
}

.nav-brand {
  display: flex; align-items: center; gap: 10px;
  font-family: 'Source Serif 4', serif;
  font-size: 22px; font-weight: 700; color: #0056D2;
  flex-shrink: 0;
}
.brand-icon {
  width: 36px; height: 36px;
  background: #0056D2; border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
}

.nav-center {
  display: flex; align-items: center; gap: 8px;
  flex: 1;
}
.nav-dropdown-trigger {
  display: flex; align-items: center; gap: 6px;
  padding: 8px 12px; border-radius: var(--radius);
  font-size: 14px; font-weight: 500; color: var(--text);
  cursor: pointer; transition: background 0.2s;
}
.nav-dropdown-trigger:hover { background: var(--bg-gray); }
.nav-dropdown-trigger i { font-size: 10px; }
.nav-link {
  padding: 8px 12px; border-radius: var(--radius);
  font-size: 14px; font-weight: 500; color: var(--text);
  transition: background 0.2s;
}
.nav-link:hover { background: var(--bg-gray); }

.nav-search {
  display: flex; align-items: center; gap: 10px;
  background: var(--bg-gray);
  border: 1.5px solid var(--border);
  border-radius: 30px;
  padding: 8px 18px;
  flex: 1; max-width: 420px;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.nav-search:focus-within {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(0,86,210,0.12);
}
.nav-search i { color: var(--text-3); font-size: 14px; }
.nav-search input {
  background: none; border: none; outline: none;
  font-family: inherit; font-size: 14px; color: var(--text);
  width: 100%;
}
.nav-search input::placeholder { color: var(--text-3); }

.nav-cta { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.btn-nav-ghost {
  padding: 8px 16px; border-radius: var(--radius);
  font-size: 14px; font-weight: 600; color: var(--blue);
  border: 1.5px solid var(--blue);
  transition: all 0.2s;
}
.btn-nav-ghost:hover { background: var(--blue-light); }
.btn-nav-primary {
  padding: 9px 18px; border-radius: var(--radius);
  font-size: 14px; font-weight: 600;
  background: var(--blue); color: #fff;
  transition: all 0.2s;
}
.btn-nav-primary:hover { background: var(--blue-dark); }

/* =====================================================
   HERO
===================================================== */
.hero-section { background: var(--bg-gray); }
.hero-grid {
  max-width: 1440px; margin: 0 auto; padding: 24px 48px;
  display: grid; grid-template-columns: 1fr 420px; gap: 16px;
}

.hero-banner {
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex; align-items: stretch;
  min-height: 340px;
}
.hero-banner--dark {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 40%, #0f3460 100%);
  justify-content: space-between;
}
.hero-banner--blue {
  background: linear-gradient(135deg, #0056D2 0%, #003B8E 100%);
  align-items: flex-end;
  padding: 32px;
}

.hero-banner-content {
  padding: 40px 36px;
  display: flex; flex-direction: column; gap: 14px;
  justify-content: center;
  max-width: 420px;
}
.hero-banner-content--sm {
  gap: 18px; justify-content: flex-end;
  padding: 0; max-width: 100%;
}
.hero-eyebrow {
  font-size: 12px; font-weight: 600; letter-spacing: 0.08em;
  color: rgba(255,255,255,0.6); text-transform: uppercase;
}
.hero-banner-title {
  font-family: 'Source Serif 4', serif;
  font-size: 34px; font-weight: 700; line-height: 1.15;
  color: #fff;
}
.hero-banner-title--sm {
  font-size: 26px;
}
.hero-banner-sub { font-size: 14px; color: rgba(255,255,255,0.75); line-height: 1.6; }
.hero-tags { display: flex; gap: 8px; flex-wrap: wrap; }
.hero-tag {
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.25);
  color: #fff; font-size: 12px; font-weight: 600;
  padding: 4px 12px; border-radius: 999px;
}
.hero-tag--teal { background: rgba(0,230,180,0.2); border-color: rgba(0,230,180,0.4); }
.btn-hero {
  display: inline-block;
  background: #fff; color: var(--blue);
  font-weight: 700; font-size: 14px;
  padding: 11px 22px; border-radius: var(--radius);
  width: fit-content;
  transition: all 0.2s;
  box-shadow: 0 4px 16px rgba(0,0,0,0.25);
}
.btn-hero:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.3); }
.btn-hero-outline {
  display: inline-block;
  border: 2px solid rgba(255,255,255,0.6); color: #fff;
  font-weight: 700; font-size: 14px;
  padding: 10px 22px; border-radius: var(--radius);
  transition: all 0.2s;
}
.btn-hero-outline:hover { background: rgba(255,255,255,0.15); border-color: #fff; }
.badge-pill {
  background: rgba(255,255,255,0.2); color: #fff;
  font-size: 12px; font-weight: 600; padding: 5px 12px;
  border-radius: 999px; width: fit-content;
  border: 1px solid rgba(255,255,255,0.3);
}

/* Dashboard preview inside hero */
.hero-banner-visual {
  padding: 32px 28px 32px 0;
  display: flex; align-items: center;
  flex-shrink: 0;
}
.dash-preview {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 12px;
  padding: 16px;
  width: 220px;
  backdrop-filter: blur(8px);
}
.dp-bar {
  display: flex; align-items: center; gap: 5px;
  margin-bottom: 14px;
}
.dp-dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; }
.dp-dot.r { background: #FC8181; }
.dp-dot.y { background: #FBBF24; }
.dp-dot.g { background: #34D399; }
.dp-label { font-size: 11px; color: rgba(255,255,255,0.5); margin-left: 4px; font-weight: 600; }
.dp-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 10px; }
.dp-stat {
  background: rgba(255,255,255,0.1); border-radius: 8px;
  padding: 10px 8px; text-align: center;
  border: 1px solid rgba(255,255,255,0.1);
}
.dp-stat i { font-size: 16px; color: rgba(255,255,255,0.7); margin-bottom: 4px; display: block; }
.dp-stat strong { display: block; font-size: 15px; font-weight: 700; color: #fff; }
.dp-stat span { font-size: 10px; color: rgba(255,255,255,0.5); }
.dp-notice {
  background: rgba(255,255,255,0.08); border-radius: 8px;
  padding: 8px 10px; font-size: 10px; color: rgba(255,255,255,0.6);
  display: flex; align-items: flex-start; gap: 6px; line-height: 1.4;
}
.dp-notice i { color: #FBBF24; flex-shrink: 0; margin-top: 1px; }

/* =====================================================
   GOAL CARDS
===================================================== */
.goals-section { padding: 20px 0; background: var(--bg-gray); }
.goals-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px;
}
.goal-card {
  display: flex; align-items: center; gap: 14px;
  background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius); padding: 18px 20px;
  cursor: pointer; transition: all 0.2s;
  font-size: 15px; font-weight: 600; color: var(--text);
}
.goal-card:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-1px); }
.goal-icon {
  width: 44px; height: 44px; border-radius: 8px;
  background: var(--blue-light);
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; color: var(--blue); flex-shrink: 0;
}
.goal-card span { flex: 1; }
.goal-arrow { color: var(--text-3); font-size: 13px; }

/* =====================================================
   PARTNERS
===================================================== */
.partners-section { padding: 28px 0; border-bottom: 1px solid var(--border); }
.partners-label {
  font-size: 13px; color: var(--text-2); font-weight: 500;
  margin-bottom: 16px;
}
.partners-strip {
  display: flex; gap: 32px; flex-wrap: wrap; align-items: center;
}
.partner-item {
  display: flex; align-items: center; gap: 7px;
  font-size: 14px; font-weight: 600; color: var(--text-2);
  opacity: 0.75; transition: opacity 0.2s;
}
.partner-item:hover { opacity: 1; color: var(--text); }
.partner-item i { font-size: 16px; }

/* =====================================================
   SECTION COMMON
===================================================== */
.section-title {
  font-family: 'Source Serif 4', serif;
  font-size: 26px; font-weight: 700;
  color: var(--text); margin-bottom: 20px;
  letter-spacing: -0.02em;
}

/* =====================================================
   TRENDING COURSES
===================================================== */
.trending-section { padding: 48px 0; border-bottom: 1px solid var(--border); }
.trending-tabs {
  display: flex; gap: 4px; margin-bottom: 24px;
  border-bottom: 1px solid var(--border); padding-bottom: 0;
}
.tab-btn {
  background: none; border: none; cursor: pointer;
  padding: 10px 16px; font-family: inherit;
  font-size: 14px; font-weight: 600; color: var(--text-2);
  border-bottom: 2px solid transparent;
  margin-bottom: -1px; transition: all 0.2s;
}
.tab-btn:hover { color: var(--text); }
.tab-btn.active { color: var(--blue); border-bottom-color: var(--blue); }
.courses-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px;
}
.course-card {
  border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; transition: all 0.2s; cursor: pointer;
}
.course-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.cc-thumb {
  height: 110px;
  display: flex; align-items: center; justify-content: center;
  font-size: 36px; color: rgba(255,255,255,0.9);
}
.cc-body { padding: 14px 16px; }
.cc-meta { font-size: 11px; font-weight: 600; color: var(--text-3); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 4px; }
.cc-title { font-size: 14px; font-weight: 700; color: var(--text); margin-bottom: 6px; line-height: 1.35; }
.cc-type { font-size: 12px; color: var(--text-2); }

/* =====================================================
   CATEGORIES
===================================================== */
.categories-section { padding: 40px 0; border-bottom: 1px solid var(--border); }
.categories-chips { display: flex; flex-wrap: wrap; gap: 10px; }
.chip {
  display: flex; align-items: center; gap: 8px;
  padding: 9px 16px; border-radius: 24px;
  border: 1.5px solid var(--border);
  font-size: 13px; font-weight: 500; color: var(--text);
  background: #fff; transition: all 0.2s;
}
.chip:hover { border-color: var(--blue); color: var(--blue); background: var(--blue-light); }
.chip i { font-size: 12px; }

/* =====================================================
   BIG BANNER
===================================================== */
.banner-section { padding: 40px 0; }
.big-banner {
  border-radius: var(--radius-lg); padding: 32px 36px;
  overflow: hidden;
}
.big-banner--purple {
  background: linear-gradient(135deg, #1a237e 0%, #4a148c 50%, #006064 100%);
  color: #fff;
}
.big-banner-text { margin-bottom: 24px; }
.big-banner-text h2 {
  font-family: 'Source Serif 4', serif;
  font-size: 22px; font-weight: 700; color: #fff; margin-bottom: 6px;
}
.big-banner-text p { font-size: 14px; color: rgba(255,255,255,0.75); }
.big-banner-cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.mini-course-card {
  background: #fff; border-radius: var(--radius); overflow: hidden;
  transition: transform 0.2s;
}
.mini-course-card:hover { transform: translateY(-3px); }
.mcc-img {
  height: 100px;
  display: flex; align-items: center; justify-content: center;
  font-size: 32px; color: rgba(255,255,255,0.85);
}
.mini-course-card strong { display: block; font-size: 13px; font-weight: 700; padding: 10px 12px 2px; color: var(--text); }
.mini-course-card span { display: block; font-size: 11px; color: var(--text-2); padding: 0 12px 10px; }

/* =====================================================
   ROLES (Explore Careers style)
===================================================== */
.roles-section { padding: 48px 0; border-bottom: 1px solid var(--border); }
.roles-header { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 24px; }
.explore-all-link { font-size: 14px; font-weight: 600; color: var(--blue); }
.explore-all-link:hover { text-decoration: underline; }
.roles-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.role-card {
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  overflow: hidden; transition: all 0.2s; cursor: pointer;
}
.role-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); border-color: rgba(0,86,210,0.25); }
.role-card-img {
  height: 140px;
  display: flex; align-items: center; justify-content: center;
}
.role-card-img--student { background: linear-gradient(135deg, #FFF3E0, #FFE0B2); }
.role-card-img--faculty { background: linear-gradient(135deg, #E3F2FD, #BBDEFB); }
.role-card-img--admin { background: linear-gradient(135deg, #E8F5E9, #C8E6C9); }
.role-card-img--analyst { background: linear-gradient(135deg, #F3E5F5, #E1BEE7); }
.role-figure {
  width: 70px; height: 70px; border-radius: 50%;
  background: rgba(0,0,0,0.08);
  display: flex; align-items: center; justify-content: center;
  font-size: 28px; color: #555;
}
.role-card h3 { font-size: 16px; font-weight: 700; padding: 16px 16px 6px; color: var(--text); }
.role-card p { font-size: 13px; color: var(--text-2); padding: 0 16px 16px; line-height: 1.55; }

/* =====================================================
   WHY SECTION
===================================================== */
.why-section { padding: 48px 0; background: var(--bg-gray); }
.why-section .section-title { text-align: center; margin-bottom: 28px; }
.why-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.why-card {
  display: flex; align-items: center; gap: 16px;
  background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px;
  transition: all 0.2s; cursor: pointer;
}
.why-card:hover { border-color: var(--blue); box-shadow: var(--shadow); }
.why-icon {
  width: 52px; height: 52px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; flex-shrink: 0;
}
.why-card div { flex: 1; }
.why-card strong { display: block; font-size: 15px; font-weight: 700; color: var(--text); margin-bottom: 3px; }
.why-card p { font-size: 13px; color: var(--text-2); line-height: 1.45; }
.why-arrow { color: var(--text-3); font-size: 14px; flex-shrink: 0; }

/* =====================================================
   POPULAR BY CATEGORY
===================================================== */
.popular-cat-section { padding: 48px 0; border-bottom: 1px solid var(--border); }
.pop-cat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.pop-cat-col { background: var(--bg-gray); border-radius: var(--radius); padding: 20px; }
.pop-cat-header {
  font-size: 14px; font-weight: 700; color: var(--blue);
  margin-bottom: 16px; padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}
.pop-cat-item {
  display: flex; align-items: center; gap: 12px;
  padding: 10px 0; border-bottom: 1px solid var(--border);
  cursor: pointer; transition: opacity 0.2s;
}
.pop-cat-item:last-child { border-bottom: none; }
.pop-cat-item:hover { opacity: 0.75; }
.pci-thumb {
  width: 44px; height: 44px; border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; color: rgba(255,255,255,0.9); flex-shrink: 0;
}
.pop-cat-item div strong { display: block; font-size: 13px; font-weight: 700; color: var(--text); margin-bottom: 2px; }
.pop-cat-item div span { font-size: 12px; color: var(--text-2); }

/* =====================================================
   TESTIMONIALS
===================================================== */
.testimonials-section { padding: 48px 0; background: var(--bg-gray); }
.testimonials-section .section-title { text-align: center; margin-bottom: 28px; }
.testimonials-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.testi-card {
  background: #fff; border-radius: var(--radius);
  padding: 20px; border: 1px solid var(--border);
  display: flex; flex-direction: column; gap: 16px;
}
.testi-card p {
  font-family: 'Source Serif 4', serif;
  font-size: 14px; color: var(--text);
  line-height: 1.65; font-style: italic; flex: 1;
}
.testi-author { display: flex; align-items: center; gap: 10px; }
.testi-avatar {
  width: 38px; height: 38px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 15px; font-weight: 700; color: #fff; flex-shrink: 0;
}
.testi-author strong { display: block; font-size: 13px; font-weight: 700; color: var(--text); }
.testi-author span { font-size: 12px; color: var(--text-2); }

/* =====================================================
   FAQ
===================================================== */
.faq-section { padding: 48px 0; border-bottom: 1px solid var(--border); }
.faq-container { max-width: 860px; }
.faq-section .section-title { margin-bottom: 24px; }
.faq-list { display: flex; flex-direction: column; }
.faq-item { border-bottom: 1px solid var(--border); }
.faq-q {
  display: flex; align-items: center; gap: 14px;
  width: 100%; background: none; border: none;
  padding: 18px 0; cursor: pointer;
  font-family: inherit; font-size: 15px; font-weight: 500;
  color: var(--text); text-align: left; transition: color 0.2s;
}
.faq-q:hover { color: var(--blue); }
.faq-icon { transition: transform 0.3s; color: var(--text-2); font-size: 13px; }
.faq-item.open .faq-icon { transform: rotate(180deg); }
.faq-a {
  display: none; padding: 0 0 18px 28px;
  font-size: 14px; color: var(--text-2); line-height: 1.7;
}
.faq-item.open .faq-a { display: block; }

/* =====================================================
   FOOTER
===================================================== */
.footer { background: #1f1f1f; color: rgba(255,255,255,0.7); padding: 48px 0 0; }
.footer-top {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px; padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand-col .footer-brand {
  display: flex; align-items: center; gap: 10px;
  margin-bottom: 12px;
}
.footer-brand .brand-icon { background: #fff; font-size: 18px; }
.footer-brand span {
  font-family: 'Source Serif 4', serif;
  font-size: 20px; font-weight: 700; color: #fff;
}
.footer-brand-col > p { font-size: 13px; line-height: 1.7; max-width: 260px; margin-bottom: 20px; }
.footer-stats { display: flex; gap: 24px; }
.fstat strong { display: block; font-size: 18px; font-weight: 700; color: #fff; }
.fstat span { font-size: 12px; }
.footer-col h4 {
  font-size: 13px; font-weight: 700; color: #fff;
  text-transform: uppercase; letter-spacing: 0.06em;
  margin-bottom: 14px;
}
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-col a { font-size: 13px; color: rgba(255,255,255,0.6); transition: color 0.2s; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  padding: 20px 0;
  display: flex; align-items: center; justify-content: space-between;
  font-size: 12px; flex-wrap: wrap; gap: 8px;
}
.footer-bottom strong { color: rgba(255,255,255,0.85); }

/* =====================================================
   RESPONSIVE
===================================================== */
@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-banner--blue { min-height: 160px; }
  .roles-grid { grid-template-columns: repeat(2, 1fr); }
  .testimonials-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 32px; }
}
@media (max-width: 768px) {
  .audience-bar { display: none; }
  .nav-center, .nav-search { display: none; }
  .goals-grid { grid-template-columns: 1fr; }
  .courses-grid { grid-template-columns: repeat(2, 1fr); }
  .big-banner-cards { grid-template-columns: repeat(2, 1fr); }
  .roles-grid { grid-template-columns: 1fr; }
  .why-grid { grid-template-columns: 1fr; }
  .pop-cat-grid { grid-template-columns: 1fr; }
  .testimonials-grid { grid-template-columns: 1fr; }
  .hero-banner-visual { display: none; }
  .hero-banner--dark { min-height: auto; }
  .footer-top { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero-grid { padding: 16px; }
  .courses-grid { grid-template-columns: 1fr; }
  .big-banner-cards { grid-template-columns: repeat(2, 1fr); }
  .partners-strip { gap: 16px; }
}