:root {
  color-scheme: light;
  --bg: #eef1f4;
  --panel: #ffffff;
  --ink: #18212f;
  --muted: #687386;
  --line: #d8dee7;
  --accent: #146c75;
  --accent-dark: #0d5158;
  --accent-soft: #e3f4f5;
  --gold: #ffb000;
  --shadow: 0 18px 50px rgba(24, 33, 47, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a {
  color: inherit;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 18px clamp(16px, 4vw, 48px);
  background: #fbfcfd;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
}

.brand img {
  width: 56px;
  height: 56px;
  object-fit: contain;
}

.brand span {
  display: grid;
  gap: 3px;
}

.brand strong {
  font-size: 1rem;
}

.brand small {
  color: var(--muted);
  font-weight: 700;
}

.app-link,
.primary,
.secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 16px;
  border-radius: 7px;
  font-weight: 850;
  text-decoration: none;
}

.app-link,
.primary {
  background: var(--accent);
  color: white;
}

.secondary {
  border: 1px solid var(--line);
  background: white;
  color: var(--accent-dark);
}

main {
  padding: 0 clamp(16px, 4vw, 48px) 36px;
}

.hero {
  display: grid;
  align-items: end;
  min-height: 430px;
  margin: 24px auto;
  padding: clamp(28px, 5vw, 56px);
  border-radius: 8px;
  background:
    linear-gradient(90deg, rgba(24, 33, 47, 0.84), rgba(24, 33, 47, 0.38)),
    url("https://images.unsplash.com/photo-1497366754035-f200968a6e72?auto=format&fit=crop&w=1800&q=80") center/cover;
  color: white;
  box-shadow: var(--shadow);
}

.hero > div {
  max-width: 760px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 14px;
  font-size: clamp(2.2rem, 5vw, 4.8rem);
  line-height: 1.02;
  letter-spacing: 0;
}

.hero p {
  max-width: 620px;
  color: rgba(255, 255, 255, 0.86);
  font-size: 1.08rem;
  line-height: 1.55;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.section {
  max-width: 1180px;
  margin: 0 auto 28px;
}

.section-title {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 14px;
}

.section-title h2 {
  margin-bottom: 0;
  font-size: 1.55rem;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.video-card {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: 0 10px 28px rgba(24, 33, 47, 0.08);
}

.video-card > div:last-child {
  padding: 14px;
}

.video-card h3 {
  margin-bottom: 7px;
  font-size: 1.02rem;
}

.video-card p {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.45;
}

.video-frame {
  aspect-ratio: 16 / 9;
  background: #dde5ec;
}

.video-frame iframe {
  width: 100%;
  height: 100%;
  border: 0;
}

.video-frame.placeholder {
  display: grid;
  place-items: center;
  padding: 16px;
  color: var(--accent-dark);
  font-weight: 850;
  text-align: center;
}

.compact {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.guide-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.guide-list a {
  padding: 13px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: #f8fafb;
  color: var(--accent-dark);
  font-weight: 800;
  text-decoration: none;
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 20px clamp(16px, 4vw, 48px);
  color: var(--muted);
  font-weight: 750;
}

@media (max-width: 860px) {
  .topbar,
  footer {
    align-items: stretch;
    flex-direction: column;
  }

  .app-link {
    width: 100%;
  }

  .hero {
    min-height: 360px;
  }

  .video-grid,
  .guide-list {
    grid-template-columns: 1fr;
  }
}