:root {
  color-scheme: light;
  --navy: #15324a;
  --navy-2: #234d69;
  --red: #c61f2b;
  --gold: #f2b134;
  --ice: #eaf4f8;
  --paper: #ffffff;
  --mist: #f4f7f9;
  --line: #d4e0e6;
  --slate: #536571;
  --ink: #17232c;
  --green: #2e7d65;
  --blue: #397cad;
  --shadow: 0 18px 50px rgba(21, 50, 74, .11);
  --radius: 18px;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 92px; }
body {
  margin: 0;
  background: var(--mist);
  color: var(--ink);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "Microsoft YaHei", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}
html[data-language="zh"] body {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  line-height: 1.75;
}
html[data-language="zh"] h1,
html[data-language="zh"] h2,
html[data-language="zh"] h3,
html[data-language="zh"] h4 { letter-spacing: 0; }
img { display: block; max-width: 100%; }
a { color: var(--navy-2); text-underline-offset: .18em; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
[hidden] { display: none !important; }

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 999;
  transform: translateY(-150%);
  padding: 10px 16px;
  border-radius: 8px;
  background: var(--gold);
  color: var(--navy);
  font-weight: 800;
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid rgba(21, 50, 74, .12);
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(12px);
}
.header-inner {
  max-width: var(--max);
  min-height: 76px;
  margin: 0 auto;
  padding: 10px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand img { width: 210px; height: auto; }
.header-tools { display: flex; align-items: center; gap: 18px; }
.text-link { font-size: .875rem; font-weight: 750; text-decoration: none; }
.text-link:hover { text-decoration: underline; }
.language-switch {
  display: flex;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--mist);
}
.language-switch button {
  min-height: 44px;
  border: 0;
  border-radius: 999px;
  padding: 7px 11px;
  background: transparent;
  color: var(--slate);
  cursor: pointer;
  font-size: .875rem;
  font-weight: 800;
}
.language-switch button[aria-pressed="true"] { background: var(--navy); color: white; }

.hero {
  position: relative;
  overflow: hidden;
  background: var(--navy);
  color: white;
}
.hero::after {
  content: "";
  position: absolute;
  right: -8%;
  bottom: -84px;
  width: 46%;
  height: 170px;
  transform: rotate(-8deg);
  background: var(--red);
}
.hero::before {
  content: "";
  position: absolute;
  right: 20%;
  top: 0;
  width: 1px;
  height: 100%;
  background: rgba(255, 255, 255, .09);
  box-shadow: 42px 0 0 rgba(255, 255, 255, .06), 84px 0 0 rgba(255, 255, 255, .04);
}
.hero-inner {
  position: relative;
  z-index: 2;
  max-width: var(--max);
  margin: 0 auto;
  padding: 46px 24px 52px;
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(310px, .75fr);
  gap: 42px;
  align-items: center;
}
.eyebrow, .section-label {
  margin: 0 0 7px;
  color: var(--red);
  font-size: .78rem;
  font-weight: 850;
  letter-spacing: .12em;
  line-height: 1.25;
  text-transform: uppercase;
}
.hero .eyebrow { color: var(--gold); }
h1, h2, h3, h4 { margin-top: 0; color: var(--navy); line-height: 1.16; }
h1 { max-width: 750px; margin-bottom: 14px; color: white; font-size: clamp(2.25rem, 5vw, 4.25rem); letter-spacing: -.04em; }
h2 { margin-bottom: 18px; font-size: clamp(1.7rem, 3vw, 2.35rem); letter-spacing: -.025em; }
h3 { margin-bottom: 8px; font-size: 1.13rem; }
h4 { margin-bottom: 5px; font-size: 1.05rem; }
p { margin: 0 0 16px; }
ul, ol { margin: 0 0 18px; padding-left: 1.35rem; }
li + li { margin-top: 7px; }
.hero-intro { max-width: 650px; margin-bottom: 24px; color: #dce8ee; font-size: 1.15rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: 9px;
  padding: 10px 15px;
  text-decoration: none;
  cursor: pointer;
  font-size: .9rem;
  font-weight: 800;
}
.button-primary { background: var(--red); color: white; }
.button-primary:hover { background: #a71621; }
.button-secondary { border-color: rgba(255, 255, 255, .38); background: white; color: var(--navy); }
.button-quiet { border-color: rgba(255, 255, 255, .38); background: transparent; color: white; }
.button:focus-visible, .language-switch button:focus-visible, summary:focus-visible, .section-nav a:focus-visible, .expand-button:focus-visible { outline: 3px solid var(--gold); outline-offset: 3px; }

.first-class-card {
  position: relative;
  min-height: 288px;
  overflow: hidden;
  border-top: 5px solid var(--gold);
  border-radius: 14px;
  padding: 27px 28px;
  background: white;
  color: var(--ink);
  box-shadow: var(--shadow);
}
.first-class-card h2 { max-width: 260px; margin-bottom: 15px; font-size: 1.45rem; }
.card-number {
  position: absolute;
  right: -12px;
  top: -24px;
  color: var(--ice);
  font-size: 6rem;
  font-weight: 900;
  letter-spacing: -.08em;
  line-height: 1;
}
.first-class-card > div:not(.card-number) { position: relative; z-index: 2; }
.check-list { list-style: none; padding: 0; }
.check-list li { position: relative; padding-left: 28px; }
.check-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: .02em;
  color: var(--green);
  font-weight: 900;
}
.check-list.compact { margin-bottom: 0; font-size: .95rem; }
.check-list.compact li + li { margin-top: 5px; }

.page-shell {
  max-width: var(--max);
  margin: 0 auto;
  padding: 30px 24px 72px;
  display: grid;
  grid-template-columns: 230px minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}
.section-nav {
  position: sticky;
  top: 106px;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 13px;
  background: white;
  box-shadow: 0 10px 28px rgba(21, 50, 74, .07);
}
.nav-heading { padding: 4px 9px 10px; color: var(--slate); font-size: .76rem; font-weight: 850; letter-spacing: .11em; text-transform: uppercase; }
.section-nav a {
  min-height: 44px;
  display: grid;
  grid-template-columns: 28px 1fr;
  gap: 8px;
  align-items: center;
  border-radius: 8px;
  padding: 9px 8px;
  color: var(--ink);
  text-decoration: none;
}
.section-nav a:hover { background: var(--ice); }
.section-nav a span { color: var(--red); font-size: .72rem; font-weight: 900; }
.section-nav a b { font-size: .88rem; }
.expand-button {
  min-height: 44px;
  width: calc(100% - 6px);
  margin: 10px 3px 2px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 9px;
  background: var(--mist);
  color: var(--navy);
  cursor: pointer;
  font-size: .82rem;
  font-weight: 800;
}

.guide-content { min-width: 0; }
.guide-section {
  scroll-margin-top: 100px;
  margin: 0 0 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: 0 9px 30px rgba(21, 50, 74, .055);
}
section.guide-section { padding: clamp(24px, 4vw, 44px); }
.critical-section { border-top: 6px solid var(--red); }
.section-kicker {
  width: 42px;
  height: 42px;
  display: inline-grid;
  place-items: center;
  margin-bottom: 17px;
  border-radius: 50%;
  background: var(--navy);
  color: white;
  font-size: .78rem;
  font-weight: 900;
}
.step-list { list-style: none; padding: 0; counter-reset: step; }
.step-list > li {
  position: relative;
  min-height: 45px;
  padding: 4px 0 18px 58px;
  counter-increment: step;
}
.step-list > li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ice);
  color: var(--navy);
  font-size: .78rem;
  font-weight: 900;
}
.step-list > li:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 18px;
  top: 39px;
  bottom: -1px;
  width: 2px;
  background: var(--line);
}
.compact-steps > li { padding-bottom: 13px; }
.notice { margin: 20px 0; border-left: 5px solid var(--blue); border-radius: 8px; padding: 15px 17px; background: #eef7fd; }
.notice-gold { border-color: var(--gold); background: #fff7e4; }
.notice-red { border-color: var(--red); background: #fff0f1; }
.notice-blue { border-color: var(--blue); background: #eef7fd; }
.split-cards, .three-up, .role-grid, .season-grid, .link-grid, .resource-grid { display: grid; gap: 14px; }
.split-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 20px; }
.three-up, .season-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); margin: 20px 0; }
.mini-card, .three-up > div, .season-grid > div, .role-grid > div {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 18px;
  background: var(--mist);
}
.mini-card p, .three-up p, .season-grid p, .role-grid p { margin-bottom: 0; font-size: .95rem; }

details.guide-section { overflow: clip; }
details.guide-section > summary {
  min-height: 106px;
  display: grid;
  grid-template-columns: 54px 1fr 30px;
  gap: 15px;
  align-items: center;
  padding: 23px 28px;
  cursor: pointer;
  list-style: none;
}
details.guide-section > summary::-webkit-details-marker { display: none; }
details.guide-section > summary .section-kicker { margin: 0; }
.summary-copy { min-width: 0; }
.summary-copy > span { display: block; }
.summary-copy strong { display: block; color: var(--navy); font-size: clamp(1.25rem, 2.5vw, 1.7rem); line-height: 1.2; }
.summary-copy .section-label { display: block; margin-bottom: 5px; }
.summary-mark {
  position: relative;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--ice);
}
.summary-mark::before, .summary-mark::after {
  content: "";
  position: absolute;
  left: 7px;
  top: 13px;
  width: 14px;
  height: 2px;
  background: var(--navy);
}
.summary-mark::after { transform: rotate(90deg); transition: transform .2s ease; }
details[open] .summary-mark::after { transform: rotate(0); }
.details-body { border-top: 1px solid var(--line); padding: clamp(24px, 4vw, 40px); }

.media-block {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(260px, .95fr);
  gap: 28px;
  align-items: center;
  margin: 26px 0 36px;
}
.media-block.reverse > div { order: 2; }
.media-block.reverse figure { order: 1; }
figure { margin: 0; }
figure img { width: 100%; border: 1px solid var(--line); border-radius: 12px; background: white; }
figcaption { margin-top: 8px; color: var(--slate); font-size: .78rem; line-height: 1.45; }

.abc-row { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin: 12px 0 25px; }
.abc-card { display: grid; grid-template-columns: 48px 1fr; gap: 12px; align-items: center; border: 1px solid var(--line); border-top: 5px solid var(--blue); border-radius: 11px; padding: 14px; }
.abc-card > b { color: var(--blue); font-size: 2.25rem; line-height: 1; }
.abc-card span { font-size: .87rem; line-height: 1.4; }
.abc-card span strong { display: block; color: var(--navy); font-size: 1rem; }
.abc-card.balance { border-top-color: var(--green); }
.abc-card.balance > b { color: var(--green); }
.abc-card.control { border-top-color: var(--red); }
.abc-card.control > b { color: var(--red); }
.role-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); margin: 12px 0 20px; }
.role { display: inline-block; margin-bottom: 8px; color: var(--red); font-size: .75rem; font-weight: 900; letter-spacing: .08em; text-transform: uppercase; }
.respect-box { margin-top: 24px; border-radius: 12px; padding: 21px 22px; background: var(--navy); color: white; }
.respect-box h3 { color: var(--gold); }
.respect-box p { margin-bottom: 0; }

.season-grid > div { border-top: 5px solid var(--red); background: white; }
.season-grid > div:nth-child(2) { border-top-color: var(--green); }
.season-grid > div:nth-child(3) { border-top-color: var(--gold); }
.season-grid span { display: block; margin-bottom: 8px; color: var(--slate); font-size: .76rem; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.season-grid strong { display: block; margin-bottom: 7px; color: var(--navy); }
.resource-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 28px; }
.resource-grid a { display: grid; grid-template-columns: 112px 1fr; gap: 14px; align-items: center; overflow: hidden; border: 1px solid var(--line); border-radius: 12px; padding: 11px; background: var(--mist); text-decoration: none; }
.resource-grid img { width: 112px; height: 88px; object-fit: cover; object-position: top; border-radius: 7px; }
.resource-grid span { color: var(--slate); font-size: .82rem; }
.resource-grid strong { display: block; margin-bottom: 4px; color: var(--navy); font-size: .95rem; }

.faq-list > div > details { border-bottom: 1px solid var(--line); }
.faq-list > div > details:first-child { border-top: 1px solid var(--line); }
.faq-list > div > details summary { position: relative; padding: 17px 45px 17px 0; color: var(--navy); cursor: pointer; font-weight: 800; list-style: none; }
.faq-list > div > details summary::-webkit-details-marker { display: none; }
.faq-list > div > details summary::after { content: "+"; position: absolute; right: 8px; top: 12px; color: var(--red); font-size: 1.55rem; font-weight: 500; }
.faq-list > div > details[open] summary::after { content: "−"; }
.faq-list > div > details p { padding: 0 45px 17px 0; }

.contact-section { border-top: 6px solid var(--gold); }
.contact-email { display: inline-block; margin: 4px 0 18px; color: var(--red); font-size: clamp(1.1rem, 3vw, 1.55rem); font-weight: 850; overflow-wrap: anywhere; }
.link-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 24px; }
.link-grid a { border: 1px solid var(--line); border-radius: 11px; padding: 17px; background: var(--mist); text-decoration: none; }
.link-grid a:hover { border-color: var(--navy-2); }
.link-grid strong, .link-grid span { display: block; }
.link-grid strong { color: var(--navy); }
.link-grid span { margin-top: 3px; color: var(--slate); font-size: .86rem; }

.site-footer { background: var(--navy); color: #dce8ee; }
.footer-inner { max-width: var(--max); margin: 0 auto; padding: 28px 24px; display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.footer-inner p { margin: 0; font-size: .84rem; }
.footer-inner strong { color: white; }
.revision-line { color: #b8cad4; }
.footer-inner a { color: var(--gold); font-weight: 800; white-space: nowrap; }

@media (max-width: 940px) {
  .hero-inner { grid-template-columns: 1fr; gap: 28px; }
  .first-class-card { max-width: 620px; min-height: auto; }
  .page-shell { grid-template-columns: 1fr; }
  .section-nav {
    top: 75px;
    z-index: 30;
    display: flex;
    gap: 6px;
    overflow-x: auto;
    padding: 8px;
    border-radius: 11px;
    scrollbar-width: thin;
  }
  .nav-heading { display: none; }
  .section-nav a { flex: 0 0 auto; display: flex; padding: 8px 10px; }
  .expand-button { flex: 0 0 auto; width: auto; margin: 0; padding: 8px 11px; }
}

@media (max-width: 720px) {
  html { scroll-padding-top: 132px; }
  .header-inner { min-height: 72px; padding: 8px 16px; gap: 12px; }
  .brand img { width: 150px; }
  .text-link { display: none; }
  .header-tools { gap: 7px; }
  .language-switch button { padding: 7px 10px; font-size: .875rem; }
  .hero-inner { padding: 32px 16px 38px; }
  h1 { font-size: clamp(2.1rem, 11vw, 3rem); }
  .hero-intro { font-size: 1rem; }
  .hero-actions { display: grid; grid-template-columns: 1fr 1fr; }
  .hero-actions .button { width: 100%; }
  .hero-actions .print-button { grid-column: 1 / -1; }
  .first-class-card { padding: 23px 21px; }
  .page-shell { padding: 18px 12px 48px; gap: 16px; }
  .section-nav { top: 72px; margin: 0 0 2px; }
  section.guide-section { padding: 24px 19px; }
  details.guide-section > summary { min-height: 92px; grid-template-columns: 44px 1fr 26px; gap: 11px; padding: 18px 17px; }
  details.guide-section > summary .section-kicker { width: 40px; height: 40px; }
  .summary-copy strong { font-size: 1.19rem; }
  .details-body { padding: 23px 18px; }
  .split-cards, .three-up, .role-grid, .season-grid, .link-grid, .resource-grid, .abc-row, .media-block { grid-template-columns: 1fr; }
  .media-block { gap: 14px; margin-bottom: 30px; }
  .media-block.reverse > div, .media-block.reverse figure { order: initial; }
  .resource-grid a { grid-template-columns: 92px 1fr; }
  .resource-grid img { width: 92px; height: 76px; }
  .footer-inner { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 520px) {
  .hero-actions { grid-template-columns: 1fr; }
  .hero-actions .print-button { grid-column: auto; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .001ms !important; }
}

@media print {
  @page { size: letter; margin: .55in; }
  body { background: white; color: black; font-size: 10.5pt; }
  .site-header, .section-nav, .hero-actions, .footer-inner a { display: none !important; }
  .hero { background: var(--navy) !important; print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .hero-inner { display: block; padding: 28px; }
  .hero-copy { margin-bottom: 20px; }
  .first-class-card { max-width: none; box-shadow: none; }
  .page-shell { display: block; max-width: none; padding: 24px 0; }
  .guide-section { break-inside: avoid; box-shadow: none; }
  details.guide-section { overflow: visible; }
  details.guide-section > summary { min-height: auto; padding: 18px 22px; }
  details.guide-section > .details-body { display: block !important; }
  .summary-mark { display: none; }
  .media-block, .three-up, .season-grid, .role-grid, .abc-row { break-inside: avoid; }
  .site-footer { background: white; color: black; border-top: 1px solid var(--line); }
  .footer-inner { display: block; padding: 18px 0; }
  a { color: black; text-decoration: none; }
}