/* ============================================================================
   页边 · 落地页样式（公开界面：纸质、克制、一页接一页）
   令牌全在 base.css；这里只排落地页。功能界面（app）用 app.css。
   ============================================================================ */

/* ---------- 1. 版面骨架 ---------- */

.landing { background: var(--ground); }

.wrap { width: 100%; max-width: 1180px; margin-inline: auto; padding-inline: clamp(20px, 4vw, 56px); }

.landing .h1 { font-size: clamp(34px, 4.1vw, 56px); line-height: 1.16; letter-spacing: -.008em; word-break: keep-all; }
.landing .h2 { font-size: clamp(26px, 2.7vw, 36px); line-height: 1.2; letter-spacing: -.008em; }
.landing .h3 { font-size: 19.5px; line-height: 1.35; }

.sec { padding-block: clamp(64px, 8vh, 104px); }
.sec-head { display: flex; align-items: baseline; justify-content: space-between; gap: 32px; margin-bottom: 34px; }
.sec-sub { font-size: 16.5px; line-height: 1.8; color: var(--muted); max-width: 46ch; }
.meta-line { font-size: 14.5px; letter-spacing: .01em; color: var(--ink-dark-3); }

.band { background: var(--paper-deep); }
html[data-theme="night"] .band { background: #0f130c; }

/* 图版：照片按「纸上的印刷品」处理，留白比图片重要 */
.plate { margin: 0; }
.plate img { display: block; width: 100%; height: auto; border-radius: 2px; }
.plate figcaption { margin-top: 10px; font-size: 14.5px; line-height: 1.65; color: var(--ink-dark-3); max-width: 40ch; }

/* ---------- 2. 页头 ---------- */

.site-head {
  position: fixed; inset: 0 0 auto; z-index: 200;
  display: flex; align-items: center; justify-content: space-between; gap: 24px;
  height: 66px; padding-inline: clamp(20px, 4vw, 56px);
  transition: background 180ms var(--ease), border-color 180ms var(--ease);
  border-bottom: 1px solid transparent;
}
.site-head.scrolled { background: var(--ground); border-bottom-color: var(--line-soft); }

.wordmark { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.wm-glyph { display: grid; place-items: center; width: 26px; height: 26px; border: 1px solid var(--ink-dark); border-radius: 2px;
  font-family: var(--font-mark); font-weight: 700; font-size: 14.5px; line-height: 1; color: var(--ink); }
.wm-text { display: flex; align-items: baseline; gap: 7px; }
.wm-text b { font-family: var(--font-display); font-weight: 600; font-size: 16.5px; letter-spacing: .01em; }
.wm-text i { font-family: var(--font-ui); font-style: normal; font-size: 14.5px; color: var(--ink-dark-3); }

.head-nav { display: flex; align-items: center; gap: clamp(14px, 2vw, 26px); margin-left: auto; }
.head-nav a { font-size: 14px; color: var(--ink-dark-2); text-decoration: none; padding-block: 4px; }
.head-nav a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 4px; }
.head-cta { font-size: 14.5px; color: var(--gold); text-decoration: none; padding: 8px 0 8px 22px; }
.head-cta:hover { text-decoration: underline; text-underline-offset: 4px; }

/* ---------- 3. 首屏：文案在左，图版在右 ---------- */

.hero { display: grid; grid-template-columns: 1.06fr .94fr; gap: clamp(28px, 5vw, 66px); align-items: end;
  padding-top: clamp(104px, 15vh, 148px); padding-bottom: clamp(52px, 7vh, 84px); }
.hero-copy { max-width: 36ch; }
.hero-note { margin-top: 22px; font-size: 18.5px; line-height: 1.8; color: var(--ink-dark-2); max-width: 40ch; }
.hero-line { margin-top: 16px; font-size: 14px; color: var(--ink-dark-3); }
.hero-act { display: flex; align-items: center; gap: 22px; margin-top: 30px; flex-wrap: wrap; }
.hero-fine { margin-top: 26px; font-size: 14.5px; color: var(--ink-dark-3); letter-spacing: .01em; }
.hero-plate { align-self: end; }
.hero-plate img { max-height: 62vh; object-fit: contain; object-position: bottom; }

/* ---------- 4. 两段话的对照 ---------- */

.cmp-grid { display: grid; grid-template-columns: 1fr 1fr; }
.compare-half { padding: clamp(22px, 3vw, 34px); background: var(--ground); }
.compare-half.dead { background: var(--ground-deep); }
.cmp-word { font-family: var(--font-display); font-weight: 600; font-size: 15px; color: var(--ink-dark-3); }
.compare-half.alive .cmp-word { color: var(--gold); }
.cmp-sub { margin-top: 10px; font-size: 15.5px; line-height: 1.75; color: var(--ink-dark); }
.frag { margin-top: 20px; }
.frag-txt { font-size: 15.5px; line-height: 1.85; color: var(--ink-dark); }
.compare-half.dead .frag-txt { color: var(--ink-dark-3); }
.frag-meta { margin-top: 12px; font-size: 14.5px; color: var(--ink-dark-3); }
.frag-link { display: inline-block; margin-top: 12px; font-size: 14.5px; color: var(--gold); text-decoration: none; }
.frag-link:hover { text-decoration: underline; text-underline-offset: 4px; }

/* ---------- 5. 六件事（宫格） ---------- */

.cells-head { display: grid; grid-template-columns: 1.05fr .95fr; gap: 34px; align-items: end; margin-bottom: 40px; }
.cells-sub { font-size: 16.5px; line-height: 1.8; color: var(--muted); }
.cell-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 44px 40px; }
.cell { display: flex; flex-direction: column; }
.cell-statement { font-family: var(--font-display); font-weight: 600; font-size: 19px; line-height: 1.35; }
.cell-copy { margin-top: 8px; font-size: 14.5px; line-height: 1.75; color: var(--ink-dark-3); }

/* --- 宫格里的四个小样（data-ui） --- */
.frag[data-ui] { background: var(--ground-deep); border-radius: 3px; padding: 14px; margin-top: 16px; }

.wc-demo { display: grid; gap: 5px; }
.wc-word { font-family: var(--font-read); font-weight: 600; font-size: 17px; line-height: 1.2; }
.wc-ipa { font-size: 14.5px; color: var(--ink-dark-3); }
.wc-en { font-family: var(--font-read); font-size: 14.5px; line-height: 1.5; }
.wc-zh { font-size: 14.5px; color: var(--ink-dark-3); }
.wc-src { margin-top: 4px; font-size: 14.5px; letter-spacing: .02em; color: var(--ink-dark-3); }

.chunk-demo p { font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-2); }
.chunk-demo p + p { margin-top: 6px; }
.chunk-demo b { font-family: var(--font-read); font-weight: 600; font-size: 14.5px; color: var(--ink); }
.chunk-demo i { font-style: normal; margin-left: 6px; color: var(--ink-dark-3); }

.q-demo .q-t { font-family: var(--font-read); font-size: 14.5px; line-height: 1.45; }
.q-demo .q-o { margin-top: 5px; font-size: 14.5px; color: var(--ink-dark-3); }
.q-demo .q-o:first-of-type { margin-top: 8px; }
.q-demo .q-why { margin-top: 9px; padding-top: 8px; border-top: 1px solid var(--line-soft); font-size: 14.5px; line-height: 1.6; color: var(--ink-dark-3); }

.shadow-demo .sd-sent { font-family: var(--font-read); font-size: 14.5px; line-height: 1.5; }
.shadow-demo .sd-hint { margin-top: 6px; font-size: 14.5px; color: var(--ink-dark-3); }
.sd-row { display: flex; align-items: center; gap: 8px; margin-top: 8px; }
.sd-bar { flex: 1; display: grid; gap: 4px; }
.sd-bar i { display: block; height: 5px; border-radius: 3px; background: var(--chart-3); }
.sd-bar i:last-child { background: var(--chart-2); }
.sd-time { font-size: 14.5px; color: var(--ink-dark-3); font-variant-numeric: tabular-nums; }

.srs-demo table { width: 100%; border-collapse: collapse; font-size: 14.5px; }
.srs-demo th { text-align: left; font-weight: 500; color: var(--ink-dark-3); padding-bottom: 5px; }
.srs-demo th:last-child, .srs-demo td:last-child { text-align: right; }
.srs-demo td { padding-block: 4px; border-top: 1px solid var(--line-soft); color: var(--ink-dark-2); }
.srs-demo td:first-child { font-family: var(--font-read); color: var(--ink); }

.ch-demo ol { display: grid; gap: 6px; counter-reset: ch; }
.ch-demo li { display: flex; align-items: baseline; gap: 7px; font-size: 14.5px; color: var(--ink-dark-2); }
.ch-demo li::before { counter-increment: ch; content: counter(ch, decimal-leading-zero); font-size: 14.5px; color: var(--ink-dark-3); }
.ch-demo li span { margin-left: auto; font-size: 14.5px; color: var(--ink-dark-3); }

/* ---------- 6. 怎么读（左问答，右样张） ---------- */

.how-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: clamp(30px, 5vw, 64px); align-items: start; }
.how-col { display: grid; gap: 26px; }
.ex-q { font-family: var(--font-display); font-weight: 600; font-size: 17px; line-height: 1.4; }
.ex-a { margin-top: 6px; font-size: 14.5px; line-height: 1.8; color: var(--ink-dark-2); }

.how-sheet { position: relative; }
.reader-demo { background: var(--paper); border-radius: 4px;
  padding: clamp(20px, 3vw, 30px) clamp(18px, 3vw, 34px); }
.rd-meta { font-size: 14.5px; color: var(--ink-dark-3); letter-spacing: .01em; }
.rd-title { margin-top: 8px; font-family: var(--font-read); font-weight: 600; font-size: 24px; line-height: 1.25; }
.rd-body { margin-top: 14px; font-family: var(--font-read); font-size: 15.5px; line-height: 1.85; color: var(--ink-dark); }
.rd-body + .rd-body { margin-top: 12px; }
.rd-note { margin-top: 18px; padding-left: 14px; border-left: 2px solid var(--gold); }
.rd-note-label { font-size: 14.5px; font-weight: 600; color: var(--gold); }
.rd-note p { margin-top: 6px; font-size: 14.5px; line-height: 1.75; color: var(--ink-dark-2); }
.rd-foot { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 18px;
  padding-top: 12px; border-top: 1px solid var(--line-soft); font-size: 14.5px; color: var(--ink-dark-3); }
.how-cap { margin-top: 12px; font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); max-width: 44ch; }
.reader-demo .mark, .reader-demo mark { background: #ecdcae; color: var(--ink-dark); padding: 0 1px; }
.gloss-static { border-bottom: 1.5px solid var(--gold); }

/* ---------- 7. 语言思维 ---------- */

.mind-grid { display: grid; grid-template-columns: 320px 1fr; gap: clamp(30px, 5vw, 70px); align-items: start; }
.mind-lead .sec-sub { margin-top: 16px; }
.mind-plate { margin-top: 30px; }
.mind-list { display: grid; gap: 34px; }
.note-row { display: grid; gap: 8px; }
.note-tag { font-family: var(--font-ui); font-weight: 600; font-size: 14.5px; color: var(--gold); }
.note-title { font-family: var(--font-display); font-weight: 600; font-size: 20px; line-height: 1.35; }
.note-ex { font-family: var(--font-read); font-size: 15.5px; line-height: 1.6; color: var(--ink-dark); }
.note-zh { font-size: 14.5px; color: var(--ink-dark-3); }
.note-why { font-size: 14.5px; line-height: 1.8; color: var(--ink-dark-2); margin-top: 4px; }

/* ---------- 8. 本周的四篇 ---------- */

.lib-head { display: flex; align-items: baseline; justify-content: space-between; gap: 30px; margin-bottom: 30px; }
.lib-note { font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); max-width: 40ch; text-align: right; }
.lib-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 26px; }
.lib-card { display: block; text-decoration: none; color: inherit; }
.lib-img { display: block; overflow: hidden; border-radius: 2px; background: var(--ground-deep); }
.lib-img img { display: block; width: 100%; aspect-ratio: 4 / 3; object-fit: cover; transition: transform 700ms var(--ease); }
.lib-card:hover .lib-img img { transform: scale(1.04); }
.lib-meta { margin-top: 10px; font-size: 14.5px; color: var(--ink-dark-3); }
.lib-title { display: block; margin-top: 4px; font-family: var(--font-read); font-weight: 600; font-size: 15.5px; line-height: 1.4; }
.lib-line { margin-top: 5px; font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); }

/* ---------- 9. 连载 ---------- */

.serial-grid { display: grid; grid-template-columns: 300px 1fr; gap: clamp(30px, 5vw, 68px); align-items: start; }
.serial-plate img { max-height: 430px; object-fit: contain; }
.serial-copy .meta-line { margin-top: 6px; }
.serial-blurb { margin-top: 14px; font-size: 16px; line-height: 1.85; color: var(--ink-dark-2); max-width: 58ch; }
.hook-list { margin-top: 18px; display: grid; gap: 7px; max-width: 58ch; }
.hook-list li { font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); padding-left: 18px; position: relative; }
.hook-list li::before { content: "—"; position: absolute; left: 0; color: var(--gold); }
.serial-act { display: flex; align-items: center; gap: 20px; margin-top: 24px; flex-wrap: wrap; }
.serial-meta { font-size: 14.5px; color: var(--ink-dark-3); }

/* ---------- 10. 数字：滑块自己算出结果 ---------- */

.fig-grid { display: grid; grid-template-columns: .88fr 1.12fr; gap: clamp(30px, 5vw, 62px); align-items: start; }
.fig-control { margin-top: 26px; }
.fig-read { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; }
.fig-read label { font-size: 14.5px; color: var(--ink-dark-3); }
.fig-val { font-family: var(--font-display); font-weight: 600; font-size: 22px; font-variant-numeric: tabular-nums; }
.fig-val b { font-weight: 600; }
.range { -webkit-appearance: none; appearance: none; width: 100%; height: 3px; margin-top: 14px; border-radius: 2px;
  background: var(--line); outline: none; cursor: pointer; }
.range::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 16px; height: 16px; border-radius: 50%;
  background: var(--ink-dark); border: 2px solid var(--ground); cursor: pointer; }
.range::-moz-range-thumb { width: 16px; height: 16px; border: 2px solid var(--ground); border-radius: 50%; background: var(--ink-dark); }
.range:focus-visible { outline: 2px solid var(--gold); outline-offset: 6px; }
.fig-foot { margin-top: 18px; font-size: 14.5px; line-height: 1.8; color: var(--ink-dark-3); max-width: 42ch; }

.fig-right { display: grid; gap: 26px; }
.fig-list { display: grid; grid-template-columns: 1fr 1fr; gap: 24px 28px; margin: 0; }
.fig-item { display: flex; flex-direction: column; }
.fig-item dt { font-size: 14.5px; color: var(--ink-dark-3); order: 2; }
.fig-item dd { margin: 0; font-family: var(--font-display); font-weight: 600; font-size: clamp(26px, 3vw, 34px);
  line-height: 1.05; font-variant-numeric: tabular-nums; }
.fig-item dd small { font-family: var(--font-ui); font-size: 14.5px; font-weight: 400; color: var(--ink-dark-3); margin-left: 4px; }
.fig-plate img { max-height: 300px; object-fit: contain; }

/* ---------- 11. 问题 ---------- */

.faq-title { margin-bottom: 8px; }
.faq-list { display: grid; }
.qa { display: grid; grid-template-columns: 5fr 6fr; gap: clamp(24px, 4vw, 68px); padding: 22px 0 24px; }
.qa + .qa { box-shadow: inset 0 1px 0 var(--line-soft); }
.q { font-family: var(--font-display); font-weight: 600; font-size: 20px; line-height: 1.45; }
.a p { font-size: 16px; line-height: 1.85; color: var(--ink-dark-2); }
.a p + p { margin-top: 8px; }

/* ---------- 12. 结尾：一张照片，一层纸 ---------- */

.close { position: relative; isolation: isolate; min-height: 68svh; display: grid; align-items: center;
  margin-top: clamp(40px, 6vh, 80px); overflow: hidden; }
.close-bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: -2; }
.close::after { content: ""; position: absolute; inset: 0; z-index: -1; background: rgba(247, 243, 232, .55); }
html[data-theme="sepia"] .close::after { background: rgba(242, 233, 214, .74); }
html[data-theme="night"] .close::after { background: rgba(18, 21, 15, .7); }
.close-inner { padding-block: clamp(60px, 10vh, 110px); }
.close-copy { max-width: 30ch; }
.close-title { font-size: clamp(30px, 3.6vw, 46px); }
.close-line { margin-top: 16px; font-size: 15px; line-height: 1.8; color: var(--ink-dark-2); }
.close-act { display: flex; align-items: center; gap: 22px; margin-top: 30px; flex-wrap: wrap; }
.close-or { margin-top: 18px; font-size: 14.5px; color: var(--ink-dark-3); }

/* ---------- 13. 页脚：版权页 ---------- */

.foot { background: var(--paper); padding-block: clamp(44px, 6vh, 68px) 30px; }
.foot-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.5fr; gap: 38px; }
.foot-brand .wordmark { margin-bottom: 12px; }
.foot-domain { font-size: 14.5px; color: var(--ink-dark-2); }
.foot-state { margin-top: 6px; font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); }
.foot-h { font-size: 14.5px; color: var(--ink-dark-3); margin-bottom: 10px; }
.foot-col { display: grid; gap: 7px; align-content: start; }
.foot-col a { font-size: 14.5px; color: var(--ink-dark-2); text-decoration: none; }
.foot-col a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }
.credit-list { display: grid; gap: 5px; }
.credit-list a { font-size: 14.5px; line-height: 1.6; color: var(--ink-dark-3); text-decoration: none; }
.credit-list a:hover { color: var(--ink-dark); text-decoration: underline; text-underline-offset: 3px; }
.foot-credit p { margin-top: 10px; font-size: 14.5px; line-height: 1.7; color: var(--ink-dark-3); }
.foot-end { display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap;
  margin-top: 30px; padding-top: 4px; font-size: 14.5px; color: var(--ink-dark-3); }
.foot-end a { color: var(--ink-dark-3); text-decoration: none; }
.foot-end a:hover { color: var(--ink-dark); text-decoration: underline; text-underline-offset: 3px; }

/* ============================================================ 封面流：核心功能八张卡 ============================================================ */
.core { padding-bottom: 58px; }
.core-head { display: grid; grid-template-columns: 1.02fr .98fr; gap: 40px; align-items: end; margin-bottom: 44px; }
.core-head .sec-sub { max-width: 40ch; }

.fan { --fan-w: 336px; --fan-h: 398px; position: relative; height: calc(var(--fan-h) + 96px); perspective: 1900px; perspective-origin: 50% 40%; overflow: hidden; }
.fan:focus-visible { outline: 2px solid var(--gold); outline-offset: 6px; }
.fan-stage { position: absolute; inset: 0 0 56px; transform-style: preserve-3d; }

.fan-card { position: absolute; top: 0; left: 50%; display: flex; flex-direction: column; width: var(--fan-w); height: var(--fan-h); margin-left: calc(var(--fan-w) / -2);
  padding: 24px 24px 18px; background: #fffdf9; border: 1px solid var(--line); border-radius: 7px;
  display: flex; flex-direction: column; transform-origin: 50% 58%; cursor: pointer; transition: border-color 200ms var(--ease); }
.fan-card.is-on { border-color: var(--line); }
.fan-card.is-on:hover { border-color: var(--ink-dark-3); }

.fan-art { background: #f4f2ea; border-radius: 3px; padding: 18px 16px; min-height: 176px; display: grid; gap: 7px; align-content: center; flex: 1; }
.fan-title { font-family: var(--font-display); font-weight: 600; font-size: 18px; line-height: 1.3; margin-top: 15px; }
.fan-note { font-size: 14.5px; line-height: 1.72; color: var(--ink-dark-3); margin-top: 5px; flex: 1; }
.fan-go { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-top: 12px; padding-top: 4px;
  font-size: 14.5px; color: var(--gold); }
.fan-go i { font-style: normal; transition: transform 200ms var(--ease); }
.fan-card:hover .fan-go i { transform: translateX(4px); }

.fa-gloss { display: flex; align-items: baseline; gap: 8px; }
.fa-word { font-family: var(--font-read); font-weight: 600; font-size: 21px; line-height: 1.2; border-bottom: 2px solid var(--gold); padding-bottom: 1px; }
.fa-ipa { font-size: 14.5px; color: var(--ink-dark-3); }
.fa-zh { font-size: 14.5px; color: var(--ink-dark); }
.fa-zh i { display: block; font-style: normal; font-size: 14.5px; line-height: 1.6; color: var(--ink-dark-3); margin-top: 4px; }
.fa-row { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; font-size: 14.5px; padding-top: 6px; box-shadow: inset 0 1px 0 var(--line-soft); }
.fa-row:first-child { box-shadow: none; padding-top: 0; }
.fa-row b { font-family: var(--font-read); font-weight: 600; font-size: 14.5px; }
.fa-row span { font-size: 14.5px; color: var(--ink-dark-3); font-variant-numeric: tabular-nums; }
.fa-quote { font-family: var(--font-read); font-size: 16px; line-height: 1.5; color: var(--ink-dark); }
.fa-bars { display: grid; gap: 5px; margin: 8px 0 2px; }
.fa-bars i { display: block; height: 6px; width: var(--w); background: var(--chart-3); border-radius: 3px; }
.fa-bars i:last-child { background: var(--chart-2); }
.fa-mini { font-size: 14.5px; line-height: 1.6; color: var(--ink-dark-3); }
.fa-opt { display: flex; align-items: baseline; gap: 6px; font-size: 14.5px; line-height: 1.45; padding: 6px 8px; border-radius: 3px; }
.fa-opt b { font-weight: 700; font-size: 14.5px; }
.fa-opt em { font-style: normal; margin-left: auto; font-size: 14.5px; opacity: .82; white-space: nowrap; }
.fa-opt.bad { background: #f4e5df; color: #7d3521; }
.fa-opt.good { background: #e6eede; color: #2f5a3a; }
.fa-ch { display: flex; align-items: baseline; gap: 8px; font-size: 14.5px; color: var(--ink-dark); }
.fa-ch b { color: var(--ink-dark-3); font-variant-numeric: tabular-nums; font-weight: 600; }
.fa-ch em { font-style: normal; margin-left: auto; font-size: 14.5px; color: var(--ink-dark-3); }
.fa-hook { font-size: 14.5px; line-height: 1.6; color: var(--ink-dark-3); box-shadow: inset 0 1px 0 var(--line-soft); padding-top: 7px; }
.fa-big { font-family: var(--font-display); font-weight: 600; font-size: 34px; line-height: 1; }
.fa-big em, .fa-big i { font-family: inherit; font-style: normal; font-size: 0.42em; color: var(--ink-dark-3); margin-left: 4px; }
.fa-post { display: flex; align-items: center; gap: 7px; font-size: 14.5px; }
.fa-av { width: 22px; height: 22px; border-radius: 50%; display: grid; place-items: center; background: #dfe3d2; color: #3d4a3a; font-size: 14.5px; }
.fa-post b { font-weight: 600; }
.fa-post em { font-style: normal; font-size: 14.5px; color: var(--ink-dark-3); }
.fa-body { font-family: var(--font-read); font-size: 14.5px; line-height: 1.58; color: var(--ink-dark); }
.fa-swatches { display: flex; gap: 6px; }
.fa-swatches i { width: 30px; height: 30px; border-radius: 3px; border: 1px solid var(--line); background: var(--c); }

.fan-ctrl { position: absolute; left: 0; right: 0; bottom: 0; display: flex; align-items: center; justify-content: center; gap: 14px; }
.fan-btn { width: 38px; height: 38px; border-radius: 3px; background: transparent; border: 1px solid var(--line); color: var(--ink-dark);
  font-size: 15px; line-height: 1; cursor: pointer; transition: background 160ms var(--ease), border-color 160ms var(--ease); }
.fan-btn:hover { background: var(--panel); border-color: var(--ink-dark-3); }
.fan-btn:focus-visible { outline: 2px solid var(--gold); outline-offset: 2px; }
.fan-count { font-size: 14.5px; color: var(--ink-dark-3); font-variant-numeric: tabular-nums; min-width: 44px; text-align: center; }
.fan-count b { color: var(--ink-dark); font-weight: 600; }

/* 兼容：旧的清单式核心功能（若出现） */
.core-list { display: grid; }
.core-row { display: grid; grid-template-columns: 1fr 210px; gap: 24px; align-items: baseline; padding-block: 18px; border-top: 1px solid var(--line-soft); }
.core-row:first-child { border-top: 0; }
.core-note { margin-top: 5px; font-size: 14px; line-height: 1.75; color: var(--ink-dark-3); }
.core-go { display: flex; align-items: center; justify-content: space-between; gap: 8px; font-size: 14px; color: var(--gold); text-decoration: none; }

/* ---------- 14. 转场 ---------- */

.page-wipe {
  visibility: hidden; position: fixed; inset: 0; z-index: 320; background: var(--ground); transform: translateY(100%); pointer-events: none; }
.scroll-bar { position: fixed; top: 0; left: 0; right: 0; height: 2px; background: var(--gold); transform: scaleX(0); transform-origin: 0 50%; z-index: 260; pointer-events: none; }
body[data-motion="off"] .page-wipe, body[data-motion="off"] .scroll-bar { display: none; }

/* ---------- 15. 断点 ---------- */

@media (max-width: 1080px) {
  .hero { grid-template-columns: 1fr; align-items: start; padding-top: clamp(96px, 13vh, 126px); }
  .hero-plate { max-width: 420px; }
  .hero-plate img { max-height: 46vh; }
  .cells-head, .core-head { grid-template-columns: 1fr; gap: 14px; }
  .cell-grid { grid-template-columns: repeat(2, 1fr); gap: 38px 32px; }
  .how-grid, .mind-grid, .fig-grid, .serial-grid { grid-template-columns: 1fr; }
  .mind-plate { max-width: 300px; }
  .serial-plate { max-width: 320px; }
  .lib-grid { grid-template-columns: repeat(2, 1fr); }
  .foot-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
  .qa { grid-template-columns: 1fr; gap: 10px; }
  .fan { --fan-w: 268px; --fan-h: 360px; }
}

@media (max-width: 760px) {
  .head-nav { display: none; }
  .sec-head { display: block; }
  .sec-head .sec-sub { margin-top: 10px; }
  .core-head { display: block; }
  .fan-stage { padding-inline: 20px; margin-inline: -20px; }
  .fan-card { flex: 0 0 84%; }
  .site-head { height: 58px; }
  .hero { padding-top: 92px; padding-bottom: 44px; }
  .hero-copy { max-width: none; }
  .hero-plate { max-width: 260px; }
  .hero-plate img { max-height: 300px; }
  .hero-note { font-size: 17px; }
  .cmp-grid { grid-template-columns: 1fr; }
  .cell-grid { grid-template-columns: 1fr; gap: 32px; }
  .lib-grid { grid-template-columns: 1fr; gap: 24px; }
  .lib-note { text-align: left; }
  .lib-head { flex-direction: column; gap: 8px; align-items: start; }
  .fig-list { grid-template-columns: 1fr 1fr; gap: 18px; }
  .close { min-height: 0; }
  .foot-grid { grid-template-columns: 1fr; gap: 26px; }
  .plate figcaption { font-size: 14.5px; max-width: 34ch; }
  .sec-sub { font-size: 15px; }
  .landing .h1 { letter-spacing: -.008em; }
  .core { background: var(--ground-deep); padding-bottom: 54px; }
  .fan { height: auto; perspective: none; overflow: visible; }
  .fan-stage { position: static; display: block; overflow: visible; padding: 0; margin: 0; transform: none; }
  .fan-card { position: relative; left: auto; top: auto; margin: 0; width: 100%; height: auto; min-height: 330px;
    display: none; transform: none !important; opacity: 1 !important; visibility: visible !important; }
  .fan-card.is-on { display: block; }
  .fan-ctrl { display: flex; justify-content: space-between; }
  .fan-art { min-height: 140px; }
}


/* ── 首屏：一张画，一个名字 ───────────────────────────── */
.hero.hero-bg { position: relative; display: block; min-height: 94svh; padding: 0; overflow: hidden; }
.hero-bg-img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: 50% 42%; filter: saturate(.9) contrast(.95); }
.hero-bg-veil { position: absolute; inset: 0; background: var(--ground); opacity: .82; }
.hero-inner { position: relative; z-index: 2; padding-top: clamp(118px, 19vh, 214px); padding-bottom: 92px; }
.hero-mark { display: flex; flex-wrap: wrap; align-items: baseline; font-family: var(--font-display); font-weight: 600; font-size: clamp(46px, 12.6vw, 188px); line-height: .88; letter-spacing: -.045em; color: var(--ink); }
.hero-mark .hm-b { font-style: italic; color: var(--gold); }
.hero-mark .hm-dot { color: var(--gold); }
.hero-say { margin-top: clamp(22px, 3vh, 34px); font-family: var(--font-read); font-size: clamp(17px, 1.55vw, 22px); line-height: 1.72; max-width: 24ch; color: var(--ink-dark-2); }
.hero-act { margin-top: 36px; display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
.hero-fine { margin-top: 28px; font-size: 13px; color: var(--ink-dark-3); }
.hero-credit { position: absolute; right: var(--gutter); bottom: 14px; z-index: 2; font-size: 13px; color: var(--ink-dark-3); opacity: .9; }

/* ── 三个入口 ─────────────────────────────────────────── */
.gate { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; margin: 66px auto 104px; background: var(--line-soft); border-radius: 4px; overflow: hidden; }
.gate-card { position: relative; display: flex; flex-direction: column; gap: 10px; min-height: 208px; padding: 30px 26px 24px; background: var(--ground); color: inherit; text-decoration: none; overflow: hidden; }
.gc-bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .5; filter: saturate(.75); }
.gc-veil { position: absolute; inset: 0; background: var(--ground); opacity: .62; }
.gate-card > .gc-k, .gate-card > .gc-t, .gate-card > .gc-d { position: relative; z-index: 2; }
.gate-card:hover { background: var(--paper-deep); }
.gc-k { font-family: var(--font-display); font-size: 20px; color: var(--gold); line-height: 1; }
.gc-t { font-family: var(--font-display); font-size: 21px; font-weight: 600; line-height: 1.35; }
.gc-d { flex: 1; font-size: 14.5px; line-height: 1.72; color: var(--ink-dark-3); }
.gc-go { position: absolute; top: 18px; right: 20px; z-index: 2; font-size: 15px; color: var(--gold); }

/* ── 功能页 ───────────────────────────────────────────── */
.fhead-band { position: relative; display: flex; align-items: flex-end; min-height: 52svh; padding-block: 122px 46px; overflow: hidden; }
.fb-img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: 50% 55%; opacity: .85; filter: saturate(.85); }
.fb-veil { position: absolute; inset: 0; background: var(--ground); opacity: .78; }
.fb-inner { position: relative; z-index: 2; }
.fb-title { font-family: var(--font-display); font-size: clamp(38px, 6.2vw, 88px); font-weight: 600; line-height: 1.06; letter-spacing: -.02em; color: var(--ink); }
.fb-line { margin-top: 18px; max-width: 46ch; font-size: 16.5px; line-height: 1.8; color: var(--ink-dark-2); }
.fgrid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; padding-block: 48px 0; }
.fcard { position: relative; display: flex; flex-direction: column; min-height: 262px; padding: 22px 20px 18px; border-radius: 6px; overflow: hidden; color: var(--ink-dark); text-decoration: none; transition: transform 240ms var(--ease); }
.fc-bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .82; filter: saturate(.8) contrast(.97); }
.fc-veil { position: absolute; inset: 0; background: var(--paper); opacity: .56; }
.fcard > .fc-verse, .fcard > .fc-name, .fcard > .fc-hint { position: relative; z-index: 2; }
.fcard:hover { transform: translateY(-3px); }
.fc-verse { font-family: var(--font-mark); font-size: 13px; letter-spacing: .02em; color: var(--ink-dark-2); }
.fc-name { margin-top: auto; font-family: var(--font-display); font-size: 24px; font-weight: 600; line-height: 1.3; }
.fc-hint { margin-top: 5px; font-size: 13.5px; line-height: 1.6; color: var(--ink-dark-2); }
.fc-go { position: absolute; top: 16px; right: 18px; z-index: 3; font-size: 15px; color: var(--gold); }
.fnote { display: flex; align-items: flex-end; justify-content: space-between; gap: 40px; flex-wrap: wrap; padding-block: 58px 100px; }
.fnote p { max-width: 54ch; font-size: 16px; line-height: 1.85; color: var(--ink-dark-2); }
.fnote-act { display: flex; align-items: center; gap: 24px; }

@media (max-width: 1080px) {
  .fgrid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 760px) {
  .hero.hero-bg { min-height: 86svh; }
  .hero-inner { padding-top: 108px; padding-bottom: 64px; }
  .hero-mark { font-size: 17.4vw; letter-spacing: -.05em; }
  .hero-say { max-width: 22ch; }
  .hero-credit { position: static; margin: 0 var(--gutter) 18px; text-align: right; }
  .gate { grid-template-columns: 1fr; margin: 40px auto 72px; }
  .fhead-band { min-height: 44svh; padding-block: 104px 30px; }
  .fgrid { grid-template-columns: 1fr; gap: 14px; }
  .fcard { min-height: 190px; }
}

/* 插画统一规格：源文件都是 640×800（竖版 4:5）或 1200×750（横版 16:10），
   这里只负责把盒子也钉成同样的形状，避免同一页上出现三种比例 */
.plate img {
  display: block; width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  border: 1px solid var(--line-soft);
  border-radius: 5px;
  background: var(--card-2);
}

/* ---------------------------------------------------------------- 第十五版
   参考 Apple 的排版习惯做「略微改动」：一句话居中、字距收紧、
   首屏不铺满图而是「文字在上、图在下」、板块间距拉大、块更少更大。
   底色、纸感、插画与中文文案都不动，只调整节奏与尺度。 */

.site-head {
  height: 62px;
  background: color-mix(in srgb, var(--ground) 84%, transparent);
  -webkit-backdrop-filter: blur(18px) saturate(150%);
  backdrop-filter: blur(18px) saturate(150%);
}
.head-nav a { font-size: 13.5px; letter-spacing: -.005em; }

.hero { padding: clamp(84px, 12vh, 148px) 0 0; text-align: center; min-height: 0; }
.hero-inner { padding-inline: var(--gutter); }
.hero-mark {
  display: flex; flex-wrap: wrap; justify-content: center;
  font-family: "Segoe UI Variable Display", "Segoe UI Variable Text", "Segoe UI", system-ui, sans-serif;
  font-weight: 700; font-size: clamp(46px, 8.6vw, 112px); line-height: .94;
  letter-spacing: -.038em; margin: 0;
}
.hm-b, .hm-dot { color: var(--gold); font-style: normal; }
.hero-say {
  margin: clamp(18px, 2.4vh, 26px) auto 0; max-width: 32ch;
  font-family: var(--font-ui); font-weight: 400;
  font-size: clamp(17px, 1.45vw, 20px); line-height: 1.62; color: var(--ink-dark-2);
}
.hero-act { justify-content: center; margin-top: clamp(24px, 3.4vh, 34px); gap: 24px; }
.hero-act .btn, .fnote-act .btn { min-height: 46px; padding: 0 26px; border-radius: 12px; font-size: 15px; }
.hero-fine { margin: 16px auto 0; font-size: 13px; color: var(--ink-dark-3); }

.hero-band { margin: clamp(40px, 6.6vh, 74px) 0 0; }
.hero-band img { display: block; width: 100%; height: min(56svh, 480px); object-fit: cover; object-position: 50% 46%; }
.hero-band figcaption {
  max-width: var(--max); margin: 12px auto 0; padding-inline: var(--gutter);
  font-size: 12.5px; color: var(--ink-dark-3); text-align: left;
}

/* 板块：更大的呼吸，标题居中 */
.sec { padding: clamp(64px, 10vh, 124px) 0; }
.core-head, .lib-head, .fnote-act { justify-items: center; text-align: center; }
.core-head .sec-sub, .lib-head .sec-sub { margin-inline: auto; }
.sec-head h2, .core-head h2, .lib-head h2 { letter-spacing: -.026em; }

/* 门卡：圆角更大，hover 时才抬起 */
.gate { gap: 14px; background: transparent; }
.gate-card { border-radius: 16px; min-height: 226px; transition: transform 260ms var(--ease), box-shadow 260ms var(--ease); }
.gate-card:hover { transform: translateY(-3px); box-shadow: 0 18px 40px rgba(28, 34, 24, .1); }

/* 功能卡：四列改三列，块更大更少 */
.fgrid { grid-template-columns: repeat(3, 1fr); gap: 22px; padding-block: 56px 0; }
.fcard {
  border-radius: 18px; min-height: 320px; padding: 26px 24px 22px;
  box-shadow: 0 1px 0 rgba(28, 34, 24, .04);
  transition: transform 280ms var(--ease), box-shadow 280ms var(--ease);
}
.fcard:hover { transform: translateY(-4px); box-shadow: 0 22px 46px rgba(28, 34, 24, .13); }
.fc-name { font-size: 27px; letter-spacing: -.02em; }
.fc-verse { font-size: 12.5px; }

/* 功能页横带：标题居中 */
.fb-inner { text-align: center; margin-inline: auto; }
.fb-line { margin-inline: auto; }
.fb-title { letter-spacing: -.03em; }

@media (max-width: 1080px) {
  .fgrid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 760px) {
  .hero { padding-top: 74px; }
  .hero-band img { height: 52svh; }
  .fgrid { grid-template-columns: 1fr; }
  .fcard { min-height: 210px; }
  .hero-act { flex-direction: column; align-items: stretch; gap: 14px; }
  .hero-act .btn { width: 100%; justify-content: center; }
}

/* 覆盖旧版两栏网格：首屏现在是「文字在上、图在下」 */
.hero.hero, .hero { display: block; grid-template-columns: none; align-items: initial; }
.hero-inner { max-width: none; }
.hero-band { width: 100%; }
.hero-band img { width: 100%; }

.hero-band figcaption.hero-cap { padding-inline: var(--gutter); margin: 12px auto 0; max-width: var(--max); }

/* 首屏在视口里垂直居中，图带只露出上半，像 Apple 的产品页那样留白 */
.hero { padding-top: 62px; }
.hero-inner {
  display: flex; flex-direction: column; justify-content: center; align-items: center;
  min-height: min(64svh, 560px); padding-inline: var(--gutter);
}
.hero-band img { object-position: 50% 46%; }

/* 图注与正文左右边距严格对齐（不依赖 --max 是否有定义） */
.hero-band figcaption.hero-cap {
  width: min(100% - 2 * var(--gutter), 1180px);
  margin: 12px auto 0; padding: 0; max-width: none;
}

/* ------------------------------------------------ 第十六版：被 pin 住的横向画廊
   桌面端：外层 pin 住，纵向滚动换算成卡片横移（Apple 产品页常见做法）。
   手机端不 pin，直接竖排，避免横向手势和页面滚动打架。 */
.fgallery { padding: clamp(56px, 8vh, 96px) 0 clamp(40px, 6vh, 72px); }
.fg-head { display: flex; flex-direction: column; align-items: center; gap: 12px; text-align: center; }
.fg-title { font-family: var(--font-display); font-weight: 600; font-size: clamp(26px, 2.7vw, 38px); letter-spacing: -.026em; margin: 0; }
.fg-hint { margin: 0; font-size: 14px; color: var(--ink-dark-3); max-width: 46ch; }
.fg-dots { display: flex; gap: 8px; margin-top: 6px; }
.fg-dots i { width: 6px; height: 6px; border-radius: 50%; background: var(--line); transition: background 200ms var(--ease), transform 200ms var(--ease); }
.fg-dots i.on { background: var(--gold); transform: scale(1.4); }
.fg-viewport { overflow: hidden; margin-top: clamp(26px, 4vh, 44px); }
.fg-track { display: flex; gap: 22px; width: max-content; padding-inline: max(var(--gutter), calc((100vw - 1180px) / 2)); will-change: transform; }
.gcard { flex: 0 0 440px; min-height: 460px; padding: 28px 26px 24px; }
.gcard .fc-name { font-size: 30px; }
.gcard .fc-hint { font-size: 14px; max-width: 26ch; }
.gcard .fc-verse { font-size: 13px; }

@media (max-width: 860px) {
  .fg-viewport { overflow: visible; }
  .fg-track { flex-direction: column; width: auto; padding-inline: var(--gutter); }
  .gcard { flex: none; width: 100%; min-height: 220px; }
  .fg-dots { display: none; }
}

/* 首页的轻微滚动吸附：只在有首屏的页面生效，且只做 proximity，不强制 */
@media (min-width: 861px) and (prefers-reduced-motion: no-preference) {
  html:has(.hero) { scroll-snap-type: y proximity; }
  .hero { scroll-snap-align: start; }
  .gate-wrap { scroll-snap-align: start; }
}

/* 被 pin 住的那一屏里，标题与卡片垂直居中 */
@media (min-width: 861px) {
  .fgallery { min-height: 100svh; display: flex; flex-direction: column; justify-content: center; padding-block: 74px 48px; }
  .fg-head { margin-bottom: 4px; }
}

/* 视差会把画带放大 7%，必须自己裁掉，否则整页横向溢出 */
.hero-band { overflow: hidden; }
/* 字标里的 learn / 点：只变颜色，不换字体也不倾斜（原来沿用旧版的斜体衬线） */
.hero-mark .hm-b, .hero-mark .hm-dot {
  font-family: inherit; font-style: normal; font-weight: inherit; letter-spacing: inherit;
  color: var(--gold);
}

/* 流畅度优化（第十七版）
   1) 顶栏不再做整屏 backdrop-filter：Windows + 集显上每帧重算模糊是最大的掉帧来源，
      改成 88% 实色 + 一条细分隔线，视觉几乎不变，滚动便宜很多。
   2) 卡片图去掉 saturate/contrast 滤镜（8 张带滤镜的层会各自合成一次），
      用罩层浓度补回同样的观感。 */
.site-head {
  background: color-mix(in srgb, var(--ground) 92%, transparent);
  -webkit-backdrop-filter: none;
  backdrop-filter: none;
  border-bottom: 1px solid var(--line-soft);
}
.site-head.scrolled { box-shadow: none; }

.fcard .fc-bg { filter: none; opacity: .78; }
.fc-veil { opacity: .62; }
.gcard .fc-bg { opacity: .8; }

.gcard, .fcard { contain: paint; }
.fg-track { will-change: transform; }

/* 画廊改成点击翻页：不再 pin、不再跟随滚轮，控制器在标题下方 */
@media (min-width: 861px) {
  .fgallery { min-height: 0; display: block; padding-block: clamp(56px, 8vh, 92px) clamp(40px, 6vh, 72px); }
}
.fg-ctl { display: flex; align-items: center; justify-content: center; gap: 14px; margin-top: 20px; }
.fg-btn {
  width: 38px; height: 38px; border-radius: 50%;
  border: 1px solid var(--line); background: transparent; color: var(--ink-dark);
  font-size: 15px; line-height: 1; cursor: pointer;
  transition: background 180ms var(--ease), border-color 180ms var(--ease), transform 180ms var(--ease);
}
.fg-btn:hover:not([disabled]) { background: var(--paper-deep); border-color: var(--ink-dark-3); }
.fg-btn:active:not([disabled]) { transform: scale(.94); }
.fg-btn[disabled] { opacity: .3; cursor: default; }
.fg-dots { display: flex; align-items: center; gap: 8px; }
.fg-dot {
  width: 8px; height: 8px; padding: 0; border: 0; border-radius: 50%;
  background: var(--line); cursor: pointer;
  transition: background 180ms var(--ease), transform 180ms var(--ease);
}
.fg-dot.on { background: var(--gold); transform: scale(1.35); }
.fg-track { transition: none; }
@media (max-width: 860px) {
  .fg-ctl { display: none; }
}