:root {
  --ink: #17202a; --muted: #586474; --paper: #f7f5ef; --panel: #ffffff;
  --accent: #bd4b2f; --accent-dark: #7c2e1c; --line: #d9d4c8; --soft: #eee9df;
  --max: 1160px; --shadow: 0 16px 44px rgba(32, 35, 42, .08);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif; line-height: 1.78; }
a { color: var(--accent-dark); text-underline-offset: .2em; }
a:focus-visible, summary:focus-visible { outline: 3px solid #e69a56; outline-offset: 3px; }
.skip { position: absolute; left: -9999px; top: .5rem; background: #fff; padding: .7rem 1rem; z-index: 20; }
.skip:focus { left: .5rem; }
.topbar { position: sticky; top: 0; z-index: 10; display: flex; align-items: center; justify-content: space-between; gap: 2rem; padding: 1rem max(1rem, calc((100vw - var(--max)) / 2)); border-bottom: 1px solid rgba(217,212,200,.9); background: rgba(247,245,239,.94); backdrop-filter: blur(10px); }
.brand { color: var(--ink); font-weight: 850; text-decoration: none; letter-spacing: -.02em; }
.topbar nav, footer nav { display: flex; gap: 1rem; flex-wrap: wrap; }
.topbar nav a, footer nav a { text-decoration: none; font-size: .92rem; }
main, footer { width: min(var(--max), calc(100% - 2rem)); margin-inline: auto; }
.page-hero { padding: clamp(3.5rem, 8vw, 7rem) 0 2.4rem; border-bottom: 1px solid var(--line); }
.page-hero h1 { max-width: 900px; margin: .25rem 0 1rem; font-family: Georgia, "Noto Serif SC", serif; font-size: clamp(2.4rem, 6vw, 5rem); line-height: 1.08; letter-spacing: -.035em; }
.lead { max-width: 820px; font-size: clamp(1.05rem, 2vw, 1.28rem); color: var(--muted); }
.eyebrow, .tag { color: var(--accent); font-size: .8rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.panel { margin: 2rem 0; padding: clamp(1.4rem, 4vw, 2.5rem); border: 1px solid var(--line); border-radius: 24px; background: var(--panel); box-shadow: var(--shadow); }
.panel h2, section > h2 { margin: .25rem 0 1rem; font-family: Georgia, "Noto Serif SC", serif; font-size: clamp(1.55rem, 3vw, 2.25rem); line-height: 1.25; }
.intro p { max-width: 900px; }
.boundary { border-left: 5px solid var(--accent); background: #fff4ed; box-shadow: none; }
.card-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.2rem; margin: 2rem 0; }
.card-grid.compact { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card { padding: 1.6rem; border: 1px solid var(--line); border-radius: 20px; background: var(--panel); }
.card h2, .card h3 { margin: .25rem 0 .7rem; line-height: 1.3; }
.card ul { padding-left: 1.15rem; color: var(--muted); }
.text-link { display: inline-block; margin-top: .5rem; font-weight: 800; }
.method ol, .checks, .steps { padding: 0; list-style: none; }
.method li, .checks li, .steps li { display: grid; grid-template-columns: 3rem 1fr; gap: 1rem; padding: 1rem 0; border-top: 1px solid var(--line); }
.method li span { display: grid; place-items: center; width: 2.4rem; height: 2.4rem; border-radius: 50%; background: var(--ink); color: #fff; font-weight: 800; }
.method li p { margin: .15rem 0; }
.checks li { display: block; }
.steps { counter-reset: steps; }
.steps li { display: block; padding-left: 3rem; position: relative; }
.steps li::before { counter-increment: steps; content: counter(steps); position: absolute; left: 0; width: 2rem; height: 2rem; border-radius: 50%; display: grid; place-items: center; background: var(--soft); font-weight: 800; }
.faq details { padding: 1rem 0; border-top: 1px solid var(--line); }
.faq summary { cursor: pointer; font-weight: 800; }
.related { margin: 2rem 0 4rem; padding: 1rem 0; }
.related ul { padding-left: 1.2rem; }
footer { display: flex; justify-content: space-between; align-items: center; gap: 2rem; padding: 2.5rem 0 4rem; border-top: 1px solid var(--line); color: var(--muted); }
@media (max-width: 760px) {
  .topbar { position: static; display: block; }
  .topbar nav { margin-top: .8rem; gap: .5rem 1rem; }
  .card-grid, .card-grid.compact { grid-template-columns: 1fr; }
  .method li { grid-template-columns: 2.5rem 1fr; }
  footer { display: block; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }