:root {
  color-scheme: light;
  --ink: #10252b;
  --muted: #617178;
  --paper: #f1f4ef;
  --card: #ffffff;
  --line: #d8e0dc;
  --accent: #ff6a2a;
  --accent-soft: #fff0e8;
  --deep: #0b1b20;
  --safe: #237a60;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); line-height: 1.75; }
a { color: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }

.guide-topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  padding: 10px max(24px, calc((100vw - 1160px) / 2));
  border-bottom: 1px solid rgba(216, 224, 220, .9);
  background: rgba(241, 244, 239, .9);
  backdrop-filter: blur(16px);
}

.guide-brand { display: flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 800; }
.guide-brand i { width: 24px; height: 24px; border: 2px solid var(--accent); transform: rotate(45deg); }
.guide-topbar nav { display: flex; gap: 8px; }
.guide-topbar nav a { padding: 8px 14px; border: 1px solid var(--line); border-radius: 999px; text-decoration: none; font-size: 14px; }
.guide-topbar nav a:last-child { border-color: var(--deep); background: var(--deep); color: white; }

.guide-hero { padding: 72px 24px 54px; background: var(--deep); color: white; }
.guide-hero > div { max-width: 1040px; margin: 0 auto; }
.guide-hero .eyebrow { display: inline-flex; gap: 8px; color: #ff9b71; font: 700 12px/1.2 ui-monospace, monospace; letter-spacing: .16em; }
.guide-hero h1 { max-width: 900px; margin: 18px 0; font-size: clamp(36px, 6vw, 68px); line-height: 1.1; letter-spacing: -.04em; }
.guide-hero p { max-width: 760px; margin: 0; color: #c9d6d8; font-size: clamp(17px, 2vw, 21px); }
.guide-meta { display: flex; flex-wrap: wrap; gap: 10px 22px; margin-top: 30px; color: #9fb1b5; font-size: 13px; }
.guide-meta span::before { content: ""; display: inline-block; width: 5px; height: 5px; margin: 0 8px 2px 0; border-radius: 50%; background: var(--accent); }

.guide-layout { display: grid; grid-template-columns: minmax(0, 1fr) 260px; gap: 32px; max-width: 1160px; margin: 0 auto; padding: 44px 24px 80px; }
.guide-article { min-width: 0; }
.guide-article > section, .guide-callout, .guide-quiz { margin-bottom: 24px; padding: clamp(22px, 4vw, 38px); border: 1px solid var(--line); border-radius: 22px; background: var(--card); }
.guide-article h2 { margin: 0 0 16px; font-size: clamp(24px, 3vw, 34px); line-height: 1.25; }
.guide-article h3 { margin: 26px 0 8px; font-size: 20px; }
.guide-article p { margin: 10px 0; }
.guide-article ul, .guide-article ol { padding-left: 22px; }
.guide-article li + li { margin-top: 8px; }
.guide-article code { padding: 2px 6px; border-radius: 5px; background: #edf1ef; font-family: ui-monospace, monospace; }

.guide-callout { border-left: 5px solid var(--accent); background: var(--accent-soft); }
.guide-callout strong { display: block; margin-bottom: 8px; font-size: 18px; }
.guide-callout p { margin: 0; }
.guide-callout.safe { border-left-color: var(--safe); background: #eaf5f1; }

.guide-table-wrap { overflow-x: auto; margin: 18px 0; border: 1px solid var(--line); border-radius: 14px; }
.guide-table { width: 100%; min-width: 680px; border-collapse: collapse; font-size: 14px; }
.guide-table th, .guide-table td { padding: 14px 16px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.guide-table th { background: #eef2ef; font-size: 13px; }
.guide-table tr:last-child td { border-bottom: 0; }
.guide-table b { color: #c44c18; }

.formula { margin: 20px 0; padding: 20px; border-radius: 14px; background: var(--deep); color: white; text-align: center; }
.formula b { display: block; font: 700 clamp(18px, 3vw, 26px)/1.4 ui-monospace, monospace; }
.formula span { display: block; margin-top: 7px; color: #aebdc0; font-size: 13px; }

.steps { list-style: none; padding: 0 !important; counter-reset: step; }
.steps li { position: relative; padding: 0 0 24px 52px; counter-increment: step; }
.steps li::before { content: counter(step, decimal-leading-zero); position: absolute; left: 0; top: 0; display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; background: var(--deep); color: white; font: 700 12px/1 ui-monospace, monospace; }
.steps li:not(:last-child)::after { content: ""; position: absolute; left: 18px; top: 40px; bottom: 3px; width: 1px; background: var(--line); }
.steps li b { display: block; margin-bottom: 3px; }

.guide-quiz details { padding: 14px 0; border-top: 1px solid var(--line); }
.guide-quiz details:first-of-type { border-top: 0; }
.guide-quiz summary { cursor: pointer; font-weight: 700; }
.guide-quiz details p { margin: 10px 0 0; color: var(--muted); }

.guide-aside { align-self: start; position: sticky; top: 88px; }
.guide-aside > div { padding: 22px; border: 1px solid var(--line); border-radius: 18px; background: var(--card); }
.guide-aside h2 { margin: 0 0 12px; font-size: 16px; }
.guide-aside a { display: block; padding: 9px 0; border-bottom: 1px solid var(--line); color: var(--muted); text-decoration: none; font-size: 14px; }
.guide-aside a:last-child { border-bottom: 0; }
.guide-aside .ask-ai { margin-top: 14px; padding: 14px; border-radius: 12px; background: var(--accent); color: #111; text-align: center; font-weight: 800; }

.guide-list { max-width: 1100px; margin: 0 auto; padding: 50px 24px 90px; }
.guide-list-head { max-width: 760px; margin-bottom: 34px; }
.guide-list-head h1 { margin: 8px 0; font-size: clamp(38px, 7vw, 70px); line-height: 1.06; }
.guide-list-head p { color: var(--muted); font-size: 18px; }
.guide-card { display: grid; grid-template-columns: 100px 1fr auto; gap: 24px; align-items: center; padding: 28px; border: 1px solid var(--line); border-radius: 22px; background: var(--card); text-decoration: none; }
.guide-card time { color: var(--accent); font: 700 12px/1.4 ui-monospace, monospace; }
.guide-card h2 { margin: 0 0 7px; font-size: 25px; }
.guide-card p { margin: 0; color: var(--muted); }
.guide-card > b { font-size: 26px; color: var(--accent); }

.guide-footer { padding: 30px 24px calc(30px + env(safe-area-inset-bottom)); background: var(--deep); color: #9fb1b5; text-align: center; font-size: 13px; }

@media (max-width: 800px) {
  .guide-topbar { padding-inline: 16px; }
  .guide-topbar nav a:first-child { display: none; }
  .guide-hero { padding: 52px 20px 38px; }
  .guide-layout { display: block; padding: 24px 14px 64px; }
  .guide-aside { position: static; margin-top: 24px; }
  .guide-article > section, .guide-callout, .guide-quiz { border-radius: 16px; }
  .guide-card { grid-template-columns: 1fr auto; gap: 12px; padding: 22px; }
  .guide-card time { grid-column: 1 / -1; }
}

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }