/* QuickQ handbook — cream paper, navy spine, gold rules */
:root {
  --paper: #f6f1e8;
  --paper-deep: #efe6d4;
  --spine: #142847;
  --gold: #c4a35a;
  --gold-soft: #d4bc7e;
  --ink: #1c1914;
  --ink-muted: #4a453c;
  --rule: rgba(20, 40, 71, 0.16);
  --rule-strong: rgba(20, 40, 71, 0.32);
  --folio: 1040px;
  --spine-w: 16px;
  --serif: "Source Han Serif SC", "Noto Serif SC", "Source Han Serif", "Songti SC", "STSong", "SimSun", "Songti", serif;
  --sans: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Heiti SC", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: auto;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.85;
  background-color: #e4dccb;
  background-image:
    radial-gradient(ellipse at top, rgba(196, 163, 90, 0.08), transparent 52%),
    repeating-linear-gradient(
      90deg,
      transparent,
      transparent 11px,
      rgba(20, 40, 71, 0.015) 12px
    );
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: var(--spine);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.22em;
}

a:hover {
  color: #0c1a33;
}

h1,
h2,
h3,
h4 {
  font-family: var(--serif);
  font-weight: 700;
  line-height: 1.35;
  color: var(--spine);
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(1.7rem, 2.6vw, 2.35rem);
  margin: 0.2rem 0 1.1rem;
}

h2 {
  font-size: clamp(1.28rem, 1.9vw, 1.62rem);
  margin: 0 0 0.85rem;
}

h3 {
  font-size: 1.08rem;
  margin: 1.35rem 0 0.55rem;
}

p {
  margin: 0 0 1rem;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.book {
  max-width: var(--folio);
  margin: 28px auto 48px;
  background: var(--paper);
  border-left: var(--spine-w) solid var(--spine);
  box-shadow:
    inset 1px 0 0 rgba(196, 163, 90, 0.55),
    0 0 0 1px rgba(20, 40, 71, 0.08),
    10px 16px 40px rgba(20, 40, 71, 0.1);
}

.inner {
  padding: 0 48px 8px 44px;
}

/* Masthead — running header */
.masthead {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 22px 48px 18px 44px;
  border-bottom: 1px solid var(--gold);
  position: relative;
}

.masthead::after {
  content: "";
  position: absolute;
  left: 44px;
  right: 48px;
  bottom: 4px;
  height: 1px;
  background: var(--spine);
  opacity: 0.18;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--spine);
  text-decoration: none;
  font-family: var(--serif);
  font-size: 1.2rem;
  letter-spacing: 0.04em;
}

.brand:hover {
  color: var(--spine);
}

.brand svg {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--spine);
  color: var(--spine);
  width: 42px;
  height: 42px;
  padding: 8px;
  cursor: pointer;
}

.nav-toggle:hover {
  background: var(--paper-deep);
}

.nav-toggle svg {
  width: 22px;
  height: 22px;
}

.site-nav {
  display: flex;
  gap: 1.6rem;
  align-items: center;
}

.site-nav a {
  font-size: 0.92rem;
  letter-spacing: 0.08em;
  text-decoration: none;
  color: var(--ink-muted);
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.site-nav a:hover {
  color: var(--spine);
  border-bottom-color: var(--gold);
}

.site-nav a.active {
  color: var(--spine);
  border-bottom-color: var(--spine);
  font-weight: 600;
}

/* Title page / hero */
.hero {
  padding: 42px 0 12px;
  border-bottom: 1px solid var(--rule);
  margin-bottom: 8px;
}

.kicker {
  font-family: var(--serif);
  font-size: 0.78rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--gold);
  margin: 0 0 0.85rem;
}

.meta-line {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.4rem;
  font-size: 0.82rem;
  color: var(--ink-muted);
  letter-spacing: 0.06em;
  margin: 0 0 1.3rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--rule);
}

.lede {
  font-size: 1.05rem;
  color: var(--ink);
}

.notice {
  font-size: 0.95rem;
  background: var(--paper-deep);
  border-left: 3px solid var(--spine);
  padding: 0.85rem 1rem;
  margin: 1.2rem 0 1.4rem;
}

/* Chapter blocks */
.chapter {
  padding: 36px 0 28px;
  border-top: 1px solid var(--rule);
}

.chapter-index {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 0.35rem;
}

.chap-no {
  font-family: var(--serif);
  font-size: 0.75rem;
  letter-spacing: 0.22em;
  color: var(--gold);
  white-space: nowrap;
}

.hairline {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), transparent 88%);
  transform: translateY(-3px);
}

.drop > p:first-of-type::first-letter {
  float: left;
  font-family: var(--serif);
  font-size: 3.05em;
  line-height: 0.82;
  padding: 0.08em 0.12em 0 0;
  color: var(--spine);
}

/* Long plates / cards */
.plates {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin: 1.4rem 0 0.4rem;
  border-top: 1px solid var(--spine);
  border-bottom: 1px solid var(--spine);
}

.plate {
  padding: 1.15rem 1.2rem 1.05rem;
  border-right: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.plate:nth-child(2n) {
  border-right: 0;
}

.plate-no {
  font-family: var(--serif);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--gold);
  margin: 0 0 0.35rem;
}

.plate h3 {
  margin-top: 0;
}

.plate p:last-child {
  margin-bottom: 0;
}

/* Essays / numbered articles */
.essay + .essay {
  margin-top: 1.6rem;
  padding-top: 1.4rem;
  border-top: 1px dashed var(--rule-strong);
}

.essay-label {
  font-family: var(--serif);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--gold);
  margin: 0 0 0.3rem;
}

/* Pull quote */
.pull {
  margin: 1.5rem 8% 1.6rem 0;
  padding: 0.2rem 0 0.2rem 1.15rem;
  border-left: 3px solid var(--gold);
  font-family: var(--serif);
  font-size: 1.12rem;
  line-height: 1.7;
  color: var(--spine);
}

.pull p {
  margin: 0;
}

/* Oral quotes */
.oral {
  margin: 1.25rem 0;
  padding: 1rem 0 0.2rem;
  border-top: 1px solid var(--gold);
}

.oral figcaption {
  font-family: var(--serif);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin-bottom: 0.45rem;
}

.oral blockquote {
  margin: 0;
  font-size: 0.98rem;
}

.oral blockquote p:last-child {
  margin-bottom: 0;
}

/* Tables */
.table-wrap {
  overflow-x: auto;
  margin: 1.1rem 0 1.3rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  line-height: 1.65;
}

th,
td {
  text-align: left;
  padding: 0.7rem 0.65rem;
  vertical-align: top;
  border-bottom: 1px solid var(--rule);
}

th {
  font-family: var(--serif);
  font-weight: 700;
  color: var(--spine);
  border-bottom: 2px solid var(--spine);
}

tr:hover td {
  background: rgba(196, 163, 90, 0.08);
}

/* CTA folio */
.cta-folio {
  margin: 1.2rem 0 1.4rem;
  padding: 1.35rem 1.4rem 1.45rem;
  background: var(--spine);
  color: #f6f1e8;
}

.cta-folio .kicker,
.cta-folio h2,
.cta-folio h3,
.cta-folio p {
  color: #f6f1e8;
}

.cta-folio p {
  color: #d9d2c4;
}

.cta-folio .kicker {
  color: var(--gold-soft);
}

.cta-folio h2,
.cta-folio h3 {
  margin-bottom: 0.7rem;
}

.btn {
  display: inline-block;
  margin-top: 0.35rem;
  padding: 0.62rem 1.25rem;
  background: var(--gold);
  color: var(--spine);
  text-decoration: none;
  font-family: var(--serif);
  letter-spacing: 0.08em;
  border: 1px solid var(--gold);
}

.btn:hover {
  background: var(--gold-soft);
  color: var(--spine);
}

.btn-ghost {
  background: transparent;
  color: var(--spine);
  border-color: var(--spine);
}

.btn-ghost:hover {
  background: var(--paper-deep);
  color: var(--spine);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.4rem;
}

.cta-mid {
  margin: 1.6rem 0;
  padding: 1.15rem 0;
  border-top: 1px solid var(--gold);
  border-bottom: 1px solid var(--gold);
}

/* Steps */
.steps {
  margin: 0.6rem 0 1.2rem;
  padding-left: 1.4rem;
}

.steps li {
  margin-bottom: 0.85rem;
  padding-left: 0.25rem;
}

.steps li::marker {
  font-family: var(--serif);
  color: var(--gold);
  font-weight: 700;
}

/* FAQ — always visible definition list */
.faq {
  margin: 0.6rem 0 0;
}

.faq dt {
  font-family: var(--serif);
  font-size: 1.02rem;
  color: var(--spine);
  margin: 1.25rem 0 0.4rem;
  padding-top: 0.9rem;
  border-top: 1px solid var(--rule);
}

.faq dt:first-child {
  border-top: 0;
  padding-top: 0;
  margin-top: 0.4rem;
}

.faq dd {
  margin: 0;
}

/* Footer / colophon */
.colophon {
  margin-top: 8px;
  padding: 28px 48px 36px 44px;
  border-top: 2px solid var(--spine);
  background: #efe8d8;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--ink-muted);
}

.colophon strong {
  color: var(--spine);
  font-weight: 600;
}

.colophon p {
  margin: 0 0 0.65rem;
}

.colophon .copy {
  padding-top: 0.7rem;
  border-top: 1px solid var(--rule);
  font-size: 0.82rem;
}

/* Essay page (zh-cn) */
.essay-page .chapter {
  border-top: 0;
  padding-top: 28px;
}

.essay-page .chapter + .chapter {
  border-top: 1px solid var(--rule);
}

/* Responsive */
@media (max-width: 860px) {
  .book {
    margin: 0;
    border-left-width: 10px;
  }

  .masthead,
  .inner,
  .colophon {
    padding-left: 22px;
    padding-right: 22px;
  }

  .masthead {
    flex-wrap: wrap;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .site-nav {
    display: none;
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    gap: 0.75rem;
    padding: 0.4rem 0 0.6rem;
  }

  .site-nav.is-open {
    display: flex;
  }

  .plates {
    grid-template-columns: 1fr;
  }

  .plate,
  .plate:nth-child(2n) {
    border-right: 0;
  }

  .pull {
    margin-right: 0;
  }

  h1 {
    font-size: 1.48rem;
  }
}

@media (max-width: 520px) {
  body {
    font-size: 16px;
  }

  .meta-line {
    flex-direction: column;
    gap: 0.2rem;
  }

  .cta-folio {
    padding: 1.1rem 1rem 1.2rem;
  }
}

/* platform download row */
.plat-row { display: flex; flex-wrap: wrap; gap: 0.55rem 0.7rem; margin: 0.9rem 0 0; }
.plat-row a { display: inline-flex; align-items: center; min-height: 2.2rem; padding: 0.25rem 0.85rem; border: 1px solid var(--gold); color: var(--spine); text-decoration: none; font-family: var(--sans); font-size: 0.86rem; background: #fffdf8; }
.plat-row a:hover { background: var(--spine); color: #fffdf8; }

@keyframes spin { to { transform: rotate(360deg); } }
a.is-loading, [data-download].is-loading { pointer-events: none; opacity: 0.88; }