:root {
  --ink: #11172c;
  --muted: #687086;
  --blue: #2258f4;
  --blue-dark: #103ec5;
  --yellow: #ffd73c;
  --line: #e2e7f0;
  --surface: #f7f9fc;
  --white: #ffffff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "Poppins", sans-serif;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

.course-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 36px;
  min-height: 74px;
  padding: 0 5vw;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, .94);
  backdrop-filter: blur(18px);
}
.course-brand { display: inline-flex; align-items: center; gap: 9px; font-size: 20px; font-weight: 800; color: var(--blue); }
.course-brand img { width: 31px; height: 31px; object-fit: contain; }
.course-header nav { display: flex; gap: 28px; font-size: 13px; font-weight: 600; }
.course-header nav a:hover { color: var(--blue); }
.course-header-actions { display: flex; align-items: center; gap: 12px; }
.header-search {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-width: 210px;
  padding: 10px 16px;
  color: #8a92a7;
  border-radius: 999px;
  background: #f4f6fa;
  font-size: 12px;
}
.header-search span { width: 12px; height: 12px; border: 1.8px solid currentColor; border-radius: 50%; position: relative; }
.header-search span::after { content: ""; position: absolute; width: 5px; height: 1.8px; right: -4px; bottom: -2px; background: currentColor; transform: rotate(45deg); }
.header-login { width: 36px; height: 36px; display: grid; place-items: center; border-radius: 50%; color: var(--white); background: var(--ink); font-size: 0; }
.header-login::before { content: "A"; font-size: 12px; font-weight: 800; }

main { overflow: hidden; }
.course-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(300px, .85fr);
  align-items: center;
  gap: 64px;
  min-height: 560px;
  padding: 84px 8vw 72px;
  background:
    radial-gradient(circle at 20% 10%, rgba(64, 133, 255, .12), transparent 30%),
    linear-gradient(145deg, #fbfcff, #f3f7ff);
}
.course-kicker { display: flex; align-items: center; gap: 10px; margin-bottom: 20px; color: #76819b; font-size: 12px; font-weight: 600; }
.course-kicker span:first-child { padding: 6px 10px; color: var(--blue); border-radius: 999px; background: #e9efff; font-weight: 800; }
.course-kicker b { color: #efb500; }
.course-hero h1 { max-width: 720px; margin: 0; font-size: clamp(44px, 5.7vw, 76px); line-height: 1.04; letter-spacing: 0; }
.course-hero-copy > p { max-width: 650px; margin: 22px 0; color: var(--muted); font-size: 16px; line-height: 1.8; }
.course-mentor-line { display: flex; align-items: center; flex-wrap: wrap; gap: 13px; color: #6f7890; font-size: 12px; }
.course-mentor-line img { width: 30px; height: 30px; border-radius: 50%; object-fit: cover; background: #e7edff; }
.course-mentor-line span:not(:first-of-type)::before { content: ""; display: inline-block; width: 3px; height: 3px; margin: 0 9px 2px 0; border-radius: 50%; background: #a2a9b9; }
.course-hero-actions { display: flex; gap: 12px; margin-top: 30px; }
.primary-action, .secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 700;
}
.primary-action { gap: 10px; color: var(--white); background: var(--blue); box-shadow: 0 14px 30px rgba(34, 88, 244, .25); }
.primary-action:hover { background: var(--blue-dark); transform: translateY(-1px); }
.secondary-action { border: 1px solid #bbc7de; background: var(--white); }
.course-hero-media { position: relative; max-width: 510px; justify-self: end; }
.course-hero-media > img { width: 100%; aspect-ratio: 1.05; border-radius: 22px; object-fit: cover; box-shadow: 0 30px 70px rgba(29, 49, 91, .18); }
.mastery-badge { position: absolute; z-index: 2; right: -28px; top: -22px; display: flex; align-items: center; gap: 12px; padding: 13px 17px; border: 1px solid rgba(255,255,255,.8); border-radius: 14px; background: rgba(255,255,255,.9); box-shadow: 0 15px 35px rgba(29,49,91,.12); backdrop-filter: blur(12px); }
.mastery-badge span { color: var(--muted); font-size: 10px; font-weight: 600; }
.mastery-badge strong { font-size: 19px; }

.course-facts {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  width: min(1080px, 88vw);
  margin: -34px auto 0;
  position: relative;
  z-index: 3;
}
.course-facts article { min-height: 112px; display: grid; place-items: center; align-content: center; border: 1px solid var(--line); border-radius: 16px; background: var(--white); box-shadow: 0 16px 35px rgba(26, 45, 86, .06); }
.course-facts strong { color: var(--blue); font-size: 25px; }
.course-facts span { color: var(--muted); font-size: 11px; }

.course-section { padding: 110px 8vw; }
.section-heading { max-width: 680px; margin-bottom: 38px; }
.section-heading.centered { margin: 0 auto 38px; text-align: center; }
.section-heading > span, .roadmap-intro > span, .mentor-section > div > span { color: var(--blue); font-size: 12px; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; }
.section-heading h2, .roadmap-intro h2, .mentor-section h2 { margin: 10px 0; font-size: clamp(30px, 4vw, 48px); line-height: 1.12; }
.section-heading p, .roadmap-intro > p, .mentor-section p { color: var(--muted); font-size: 14px; line-height: 1.75; }
.curriculum-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.curriculum-card { overflow: hidden; border: 1px solid var(--line); border-radius: 18px; background: var(--white); transition: transform .25s ease, box-shadow .25s ease; }
.curriculum-card:hover { transform: translateY(-4px); box-shadow: 0 18px 45px rgba(26, 45, 86, .1); }
.curriculum-card img { width: 100%; aspect-ratio: 1.65; object-fit: cover; }
.curriculum-card span { display: block; margin: 20px 22px 7px; color: var(--blue); font-size: 11px; font-weight: 800; text-transform: uppercase; }
.curriculum-card h3 { margin: 0 22px 7px; font-size: 18px; }
.curriculum-card p { margin: 0 22px 24px; color: var(--muted); font-size: 12px; line-height: 1.7; }

.roadmap-section {
  display: grid;
  grid-template-columns: .8fr 1.2fr;
  gap: 72px;
  padding: 110px 8vw;
  background: var(--surface);
}
.roadmap-intro { align-self: start; position: sticky; top: 120px; }
.certificate-note { display: flex; gap: 12px; max-width: 290px; margin-top: 28px; padding: 16px; border: 1px solid var(--line); border-radius: 14px; background: var(--white); }
.certificate-note > span { flex: 0 0 auto; width: 28px; height: 28px; display: grid; place-items: center; color: var(--white); background: var(--blue); border-radius: 50%; font-weight: 800; }
.certificate-note strong { font-size: 13px; }
.certificate-note p { margin: 4px 0 0; color: var(--muted); font-size: 11px; line-height: 1.6; }
.roadmap-list { position: relative; display: grid; gap: 26px; }
.roadmap-list::before { content: ""; position: absolute; left: 24px; top: 30px; bottom: 30px; width: 1px; background: #cdd8ef; }
.roadmap-list article { position: relative; display: grid; grid-template-columns: 50px 1fr; gap: 18px; align-items: start; }
.roadmap-list b { z-index: 1; width: 50px; height: 50px; display: grid; place-items: center; border: 1px solid #ccd7ef; border-radius: 50%; color: var(--blue); background: var(--white); font-size: 12px; }
.roadmap-list article > div { padding: 25px 28px; border: 1px solid var(--line); border-radius: 17px; background: var(--white); box-shadow: 0 12px 25px rgba(26, 45, 86, .04); }
.roadmap-list span { color: var(--blue); font-size: 10px; font-weight: 800; text-transform: uppercase; }
.roadmap-list h3 { margin: 8px 0; font-size: 19px; }
.roadmap-list p { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.7; }

.outcomes-section { background: var(--white); }
.outcome-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.outcome-grid article { position: relative; overflow: hidden; min-height: 330px; border-radius: 20px; background: #0c1425; }
.outcome-grid img { width: 100%; height: 100%; position: absolute; inset: 0; object-fit: cover; opacity: .72; transition: transform .4s ease; }
.outcome-grid article:hover img { transform: scale(1.04); }
.outcome-grid article::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, transparent 35%, rgba(4, 10, 25, .92)); }
.outcome-grid div { position: absolute; z-index: 2; left: 28px; bottom: 25px; color: var(--white); }
.outcome-grid span { color: #93b3ff; font-size: 11px; font-weight: 800; text-transform: uppercase; }
.outcome-grid h3 { margin: 7px 0 0; font-size: 22px; }

.enrollment-section {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 32px;
  padding: 105px 8vw;
  background: var(--surface);
}
.community-card, .enroll-card { border: 1px solid var(--line); border-radius: 20px; background: var(--white); box-shadow: 0 18px 45px rgba(26, 45, 86, .06); }
.community-card { padding: 28px; }
.community-heading { display: flex; align-items: center; justify-content: space-between; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.community-heading span { font-size: 19px; font-weight: 700; }
.community-heading strong { color: var(--blue); font-size: 11px; }
.community-message { display: flex; gap: 12px; max-width: 72%; margin-top: 24px; }
.community-message.reply { margin-left: auto; }
.community-message b { flex: 0 0 auto; width: 32px; height: 32px; display: grid; place-items: center; border-radius: 50%; color: var(--white); background: var(--blue); font-size: 10px; }
.community-message p { margin: 0; padding: 13px 15px; border-radius: 0 14px 14px 14px; color: #4f596f; background: #f3f6fb; font-size: 12px; line-height: 1.6; }
.community-input { display: flex; justify-content: space-between; margin-top: 28px; padding: 13px 15px; color: #959caf; border: 1px solid var(--line); border-radius: 999px; font-size: 11px; }
.community-input span { color: var(--blue); }
.enroll-card { padding: 26px; }
.enroll-card > span { display: inline-block; padding: 5px 9px; color: #8b6c00; border-radius: 999px; background: #fff4bd; font-size: 10px; font-weight: 800; text-transform: uppercase; }
.enroll-card > p { margin: 10px 0 20px; color: var(--muted); font-size: 12px; }
.enroll-price { display: flex; align-items: baseline; gap: 9px; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.enroll-price strong { color: var(--blue); font-size: 33px; }
.enroll-price small { color: var(--muted); font-size: 10px; }
.enroll-card ul { display: grid; gap: 12px; margin: 22px 0; padding: 0; list-style: none; }
.enroll-card li { color: #596276; font-size: 12px; }
.enroll-card li::before { content: "✓"; margin-right: 9px; color: var(--blue); font-weight: 800; }
.enroll-card > a { display: flex; align-items: center; justify-content: center; gap: 10px; min-height: 48px; color: var(--white); border-radius: 999px; background: var(--blue); font-size: 13px; font-weight: 800; box-shadow: 0 14px 28px rgba(34, 88, 244, .22); }
.enroll-card > a:hover { background: var(--blue-dark); }

.mentor-section { display: grid; grid-template-columns: 240px minmax(0, 660px); justify-content: center; align-items: center; gap: 52px; padding: 100px 8vw; }
.mentor-section > img { width: 240px; height: 240px; object-fit: contain; border-radius: 50%; background: #edf2ff; }
.mentor-stats { display: flex; gap: 20px; margin-top: 20px; color: var(--blue); font-size: 12px; }

footer { display: flex; align-items: center; gap: 24px; padding: 28px 8vw; color: #adb4c4; background: #070a13; font-size: 12px; }
footer .course-brand { color: var(--white); }
footer p { margin-right: auto; }
footer div { display: flex; gap: 22px; }
footer a:hover { color: var(--white); }

@media (max-width: 900px) {
  .course-header { grid-template-columns: 1fr auto; padding: 0 22px; }
  .course-header nav, .header-search { display: none; }
  .course-hero { grid-template-columns: 1fr; gap: 40px; padding: 64px 24px; }
  .course-hero-media { justify-self: stretch; max-width: none; }
  .course-facts { grid-template-columns: repeat(2, 1fr); }
  .curriculum-grid, .roadmap-section, .enrollment-section { grid-template-columns: 1fr; }
  .roadmap-intro { position: static; }
  .mentor-section { grid-template-columns: 1fr; text-align: center; }
  .mentor-section > img { margin: auto; }
  .mentor-stats { justify-content: center; }
}

@media (max-width: 620px) {
  .course-hero h1 { font-size: 42px; }
  .course-hero-actions, .course-mentor-line { align-items: stretch; flex-direction: column; }
  .course-mentor-line img { display: none; }
  .course-mentor-line span:not(:first-of-type)::before { display: none; }
  .mastery-badge { right: 12px; top: -18px; }
  .course-facts { gap: 12px; width: calc(100% - 32px); }
  .course-facts article { min-height: 90px; }
  .course-section, .roadmap-section, .enrollment-section, .mentor-section { padding: 74px 20px; }
  .curriculum-grid, .outcome-grid { grid-template-columns: 1fr; }
  .outcome-grid article { min-height: 240px; }
  .community-heading, footer { align-items: flex-start; flex-direction: column; }
  .community-message { max-width: 100%; }
  footer p { margin: 0; }
}

/* Final compact phone guard. */
@media (max-width: 640px) {
  html,
  body {
    width: 100% !important;
    overflow-x: hidden !important;
  }

  .course-header {
    min-height: auto !important;
    grid-template-columns: 1fr auto !important;
    gap: 12px !important;
    padding: 12px 14px !important;
  }

  .course-brand {
    min-width: 0 !important;
    font-size: 15px !important;
  }

  .course-header-actions {
    gap: 8px !important;
  }

  .course-hero {
    min-height: 0 !important;
    gap: 24px !important;
    padding: 38px 16px 42px !important;
  }

  .course-hero h1 {
    font-size: clamp(32px, 11vw, 42px) !important;
  }

  .course-hero-copy > p {
    font-size: 14px !important;
    line-height: 1.65 !important;
  }

  .course-hero-media > img {
    border-radius: 18px !important;
  }

  .mastery-badge {
    position: static !important;
    width: 100% !important;
    margin: 12px 0 0 !important;
  }

  .course-facts {
    width: calc(100% - 28px) !important;
    grid-template-columns: 1fr 1fr !important;
    margin-top: 18px !important;
  }

  .course-section,
  .roadmap-section,
  .enrollment-section,
  .mentor-section {
    padding: 46px 16px !important;
  }

  .curriculum-grid,
  .roadmap-section,
  .outcome-grid,
  .enrollment-section,
  .mentor-section {
    grid-template-columns: 1fr !important;
  }

  .roadmap-list article {
    grid-template-columns: 38px minmax(0, 1fr) !important;
    gap: 12px !important;
  }

  .roadmap-list b {
    width: 38px !important;
    height: 38px !important;
  }

  .roadmap-list::before {
    left: 18px !important;
  }

  .roadmap-list article > div,
  .community-card,
  .enroll-card {
    padding: 18px !important;
  }

  .community-input {
    border-radius: 16px !important;
  }

  .mentor-stats,
  footer,
  footer div {
    flex-direction: column !important;
    align-items: flex-start !important;
    gap: 12px !important;
  }
}

@media (max-width: 380px) {
  .course-facts {
    grid-template-columns: 1fr !important;
  }

  .primary-action,
  .secondary-action {
    width: 100% !important;
  }
}

/* Device comfort layer for tablets and touch. */
@media (max-width: 1024px) and (min-width: 641px) {
  .course-header {
    gap: 18px !important;
    padding: 12px 28px !important;
  }

  .course-hero,
  .roadmap-section,
  .enrollment-section {
    grid-template-columns: 1fr !important;
    padding-left: 28px !important;
    padding-right: 28px !important;
  }

  .course-hero-media {
    width: min(100%, 620px) !important;
    justify-self: center !important;
  }

  .course-facts {
    width: calc(100% - 56px) !important;
    grid-template-columns: repeat(2, minmax(0, 1fr)) !important;
  }

  .curriculum-grid,
  .outcome-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr)) !important;
  }
}

@media (hover: none) and (pointer: coarse) {
  a,
  button,
  .primary-action,
  .secondary-action,
  .enroll-card > a {
    min-height: 44px;
  }

  input,
  select,
  textarea {
    font-size: 16px !important;
  }

  .curriculum-card:hover,
  .outcome-grid article:hover img {
    transform: none !important;
  }
}