/* Static protocol learning pages for ARServer. */

.learn-body {
  color: #1f2937;
}

.learn-hero {
  padding-block: 72px 34px;
}

.learn-hero__inner {
  display: grid;
  gap: 22px;
  max-width: 960px;
}

.learn-hero h1 {
  margin: 0;
  color: #0f172a;
  font-size: clamp(2.35rem, 5vw, 4.7rem);
  line-height: 0.98;
  letter-spacing: -0.065em;
}

.learn-hero p {
  max-width: 820px;
  color: #526077;
  font-size: clamp(1.02rem, 1.5vw, 1.2rem);
  line-height: 1.72;
}

.learn-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 28px;
  align-items: start;
  padding-block: 30px 82px;
}

.learn-sidebar {
  position: sticky;
  top: 108px;
  display: grid;
  gap: 10px;
  padding: 18px;
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.74);
  box-shadow: 0 18px 48px rgba(15, 23, 42, 0.07);
}

.learn-sidebar strong {
  color: #0f172a;
  font-size: 0.88rem;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.learn-sidebar a {
  display: block;
  padding: 10px 12px;
  border-radius: 14px;
  color: #4b5870;
  font-size: 0.94rem;
  line-height: 1.35;
  text-decoration: none;
}

.learn-sidebar a:hover,
.learn-sidebar a.is-active {
  color: #0f172a;
  background: rgba(239, 246, 255, 0.9);
}

.learn-article {
  overflow: hidden;
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 30px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 22px 70px rgba(15, 23, 42, 0.08);
}

.learn-article__header {
  padding: 30px 34px;
  border-bottom: 1px solid rgba(15, 23, 42, 0.08);
  background: linear-gradient(135deg, rgba(239, 246, 255, 0.86), rgba(255, 247, 237, 0.62));
}

.learn-article__header span {
  color: #f97316;
  font-size: 0.78rem;
  font-weight: 650;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.learn-article__header h2 {
  margin: 10px 0 0;
  color: #0f172a;
  font-size: clamp(1.6rem, 3vw, 2.45rem);
  letter-spacing: -0.04em;
  line-height: 1.08;
}

.learn-content {
  max-width: 880px;
  padding: 34px;
  font-size: 16.5px;
  line-height: 1.72;
}

.learn-content h3 {
  margin: 30px 0 12px;
  color: #0f172a;
  font-size: 1.35rem;
  line-height: 1.25;
  letter-spacing: -0.018em;
}

.learn-content p {
  margin: 0 0 16px;
  color: #334155;
}

.learn-content ul,
.learn-content ol {
  margin: 0 0 18px;
  padding-left: 1.45em;
  color: #334155;
}

.learn-content li + li {
  margin-top: 8px;
}

.learn-content strong {
  color: #0f172a;
  font-weight: 600;
}

.learn-content code {
  font-family: "Sometype Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  padding: 0.14em 0.38em;
  border-radius: 6px;
  background: rgba(15, 23, 42, 0.06);
  font-size: 0.88em;
}

.learn-callout {
  margin: 24px 0;
  padding: 18px 20px;
  border: 1px solid rgba(37, 99, 235, 0.16);
  border-left: 4px solid #2563eb;
  border-radius: 18px;
  background: rgba(239, 246, 255, 0.72);
  color: #334155;
}

.learn-link-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 24px;
}

.learn-link-grid a {
  display: grid;
  gap: 6px;
  padding: 18px;
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 18px;
  color: #0f172a;
  text-decoration: none;
  background: rgba(255, 255, 255, 0.72);
}

.learn-link-grid a:hover {
  border-color: rgba(37, 99, 235, 0.24);
  background: rgba(239, 246, 255, 0.78);
}

.learn-link-grid span {
  color: #64748b;
  font-size: 0.92rem;
  line-height: 1.45;
}

@media (max-width: 980px) {
  .learn-layout {
    grid-template-columns: 1fr;
  }

  .learn-sidebar {
    position: static;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .learn-sidebar strong {
    grid-column: 1 / -1;
  }
}

@media (max-width: 640px) {
  .learn-hero {
    padding-block: 44px 18px;
  }

  .learn-content,
  .learn-article__header {
    padding: 24px;
  }

  .learn-sidebar,
  .learn-link-grid {
    grid-template-columns: 1fr;
  }
}