:root {
  --bg: #0a0a0f;
  --beige: #f6f4f1;
  --azure: #62b0f5;
  --cream: #fffdf6;
  --border: rgba(246, 244, 241, 0.10);
  --card: rgba(246, 244, 241, 0.03);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }

body {
  font-family: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--beige);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  line-height: 1.6;
}

.top-bar {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(10, 10, 15, 0.7);
  border-bottom: 1px solid var(--border);
}
.top-bar-inner {
  max-width: 760px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.top-bar a.logo-link { display: inline-block; line-height: 0; }
.top-bar img { width: 130px; height: auto; opacity: 0.95; }
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: rgba(246, 244, 241, 0.6);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s ease;
}
.back-link:hover { color: var(--azure); }
.back-link svg { width: 16px; height: 16px; }

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 64px 24px 80px;
}

h1 {
  font-size: clamp(32px, 5vw, 44px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin-bottom: 10px;
}
h1 .grad {
  background: linear-gradient(135deg, var(--azure) 0%, #a78bfa 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.subtitle {
  color: rgba(246, 244, 241, 0.6);
  font-size: 14px;
  margin-bottom: 48px;
}

section {
  margin-bottom: 48px;
}
section .head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 16px;
}
section .num {
  color: rgba(98, 176, 245, 0.4);
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 13px;
  font-weight: 500;
  flex-shrink: 0;
}
section h2 {
  font-size: clamp(18px, 2.5vw, 22px);
  font-weight: 600;
  letter-spacing: -0.01em;
}
section .body {
  padding-left: 36px;
  color: rgba(246, 244, 241, 0.72);
}
section .body > * + * { margin-top: 12px; }

.card {
  padding: 16px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--card);
}
.card p { color: rgba(246, 244, 241, 0.6); }
.card p:first-child { color: var(--beige); font-weight: 600; }

ul {
  list-style: disc;
  padding-left: 22px;
  color: rgba(246, 244, 241, 0.7);
}
ul li + li { margin-top: 4px; }

a {
  color: var(--azure);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

.note {
  color: rgba(246, 244, 241, 0.55);
  font-size: 13px;
}

h4 {
  font-size: 15px;
  font-weight: 600;
  color: rgba(246, 244, 241, 0.9);
  margin-top: 16px;
}

footer {
  margin-top: 64px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

@media (max-width: 600px) {
  main { padding: 40px 20px 60px; }
  section .body { padding-left: 0; }
  section .head { flex-direction: column; gap: 4px; }
}