:root {
  --paper: #f5f1e8;
  --paper-deep: #ebe4d6;
  --ink: #20211d;
  --muted: #6d6b63;
  --line: rgba(32, 33, 29, .17);
  --accent: #d86748;
  --accent-soft: #f2c3a9;
  --max: 1240px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif; font-synthesis: none; }
a { color: inherit; text-decoration: none; }
img, video { display: block; max-width: 100%; }
button, video { font: inherit; }

.case-page { width: min(var(--max), calc(100% - 64px)); margin: 0 auto; }
.site-nav { display: flex; justify-content: space-between; align-items: center; padding: 24px 0; border-bottom: 1px solid var(--line); font-size: 13px; }
.site-nav__brand { font-weight: 800; letter-spacing: -.05em; }
.site-nav__links { display: flex; gap: 24px; color: var(--muted); }
.site-nav__links a:hover { color: var(--accent); }

.case-hero { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: clamp(44px, 6vw, 84px); align-items: center; padding: clamp(72px, 8vw, 112px) 0 82px; }
.eyebrow, .section-index { margin: 0 0 18px; color: var(--accent); font: 10px/1.2 ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .16em; text-transform: uppercase; }
.case-hero h1 { max-width: 640px; margin: 0; font-size: clamp(48px, 5.3vw, 76px); line-height: 1.12; letter-spacing: -.045em; font-weight: 700; }
.case-hero h1 span { display: block; }
.hero-lead { max-width: 490px; margin: 24px 0 0; color: #4e4e47; font-size: clamp(16px, 1.25vw, 18px); line-height: 1.85; letter-spacing: .01em; }
.hero-link { display: inline-flex; align-items: center; gap: 8px; margin-top: 36px; padding-bottom: 8px; border-bottom: 1px solid var(--ink); font-size: 13px; }
.hero-link:hover { color: var(--accent); border-color: var(--accent); }
.hero-media { position: relative; display: flex; justify-content: center; padding: 22px 22px 48px; background: var(--paper-deep); }
.hero-media::before { position: absolute; inset: 0; border: 1px solid rgba(32,33,29,.1); content: ''; pointer-events: none; }
.hero-video { position: relative; width: min(100%, 340px); margin: 0; background: #11120f; }
.hero-video video { width: 100%; aspect-ratio: 9 / 16; object-fit: contain; background: #11120f; }
.hero-video figcaption { position: absolute; right: 14px; bottom: 12px; left: 14px; color: #fff; font-size: 11px; letter-spacing: .02em; text-shadow: 0 1px 8px rgba(0,0,0,.45); }
.hero-note { position: absolute; right: -12px; bottom: 8px; display: grid; gap: 3px; min-width: 156px; padding: 14px 16px; background: var(--accent); color: #fff; transform: rotate(-2deg); }
.hero-note strong { font-size: 18px; letter-spacing: -.04em; }
.hero-note span { font: 9px ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .09em; }

.section { padding: 86px 0; border-top: 1px solid var(--line); }
.section-head { display: grid; grid-template-columns: 90px minmax(0, 1fr); gap: 24px; align-items: start; margin-bottom: 44px; }
.section-head h2 { max-width: 790px; margin: 0; font-size: clamp(32px, 4.5vw, 60px); line-height: 1.12; letter-spacing: -.045em; font-weight: 600; }
.section-index { margin-top: 9px; }
.intro-grid { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(260px, .7fr); gap: clamp(40px, 9vw, 150px); }
.intro-grid p { margin: 0; color: #4d4d46; font-size: 18px; line-height: 1.75; }
.meta-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px 34px; margin: 0; }
.meta-grid div { padding-top: 12px; border-top: 1px solid var(--line); }
.meta-grid dt { margin-bottom: 8px; color: var(--muted); font: 10px ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .1em; text-transform: uppercase; }
.meta-grid dd { margin: 0; font-size: 13px; line-height: 1.55; }

.process-grid { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.process-step { min-height: 210px; padding: 18px 18px 24px 0; border-right: 1px solid var(--line); }
.process-step + .process-step { padding-left: 18px; }
.process-step:last-child { border-right: 0; }
.process-step__no { color: var(--accent); font: 11px ui-monospace, SFMono-Regular, Consolas, monospace; }
.process-step h3 { margin: 42px 0 12px; font-size: 20px; letter-spacing: -.04em; }
.process-step p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.65; }

.examples { background: #22231f; color: #f8f5ed; margin-left: calc((min(var(--max), 100vw - 64px) - 100vw) / 2); margin-right: calc((min(var(--max), 100vw - 64px) - 100vw) / 2); padding: 92px max(32px, calc((100vw - var(--max)) / 2)) 110px; }
.examples .section-head { border-color: rgba(255,255,255,.2); }
.examples .section-index { color: var(--accent-soft); }
.examples .section-head h2 { color: #f8f5ed; }
.examples-intro { max-width: 600px; margin: -20px 0 42px 114px; color: #b6b5ac; font-size: 15px; line-height: 1.7; }
.example-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 42px 22px; }
.example-card { min-width: 0; }
.example-media { position: relative; display: flex; justify-content: center; background: #0e0f0d; }
.example-media video { width: min(100%, 300px); aspect-ratio: 9 / 16; object-fit: contain; background: #0e0f0d; }
.example-media::after { position: absolute; inset: 0; border: 1px solid rgba(255,255,255,.15); content: ''; pointer-events: none; }
.example-top { display: flex; justify-content: space-between; gap: 16px; align-items: baseline; margin-bottom: 12px; color: var(--accent-soft); font: 10px ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .08em; }
.example-card h3 { margin: 14px 0 8px; font-size: clamp(21px, 2vw, 28px); letter-spacing: -.035em; }
.example-card > p { max-width: 520px; margin: 0; color: #b9b8b0; font-size: 13px; line-height: 1.8; }
.example-details { display: grid; grid-template-columns: 1fr; gap: 12px; margin: 18px 0 0; padding-top: 14px; border-top: 1px solid rgba(255,255,255,.16); }
.example-details dt { margin-bottom: 6px; color: #8f9088; font: 9px ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .08em; text-transform: uppercase; }
.example-details dd { margin: 0; color: #e1dfd5; font-size: 12px; line-height: 1.55; }

.notes-grid { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: clamp(42px, 9vw, 140px); }
.notes-grid h2 { max-width: 500px; margin: 0; font-size: clamp(32px, 4.5vw, 56px); line-height: 1.12; letter-spacing: -.045em; }
.note-list { display: grid; gap: 0; }
.note-item { display: grid; grid-template-columns: 42px 1fr; gap: 14px; padding: 18px 0; border-top: 1px solid var(--line); }
.note-item:last-child { border-bottom: 1px solid var(--line); }
.note-item b { color: var(--accent); font: 11px ui-monospace, SFMono-Regular, Consolas, monospace; }
.note-item h3 { margin: 0 0 8px; font-size: 18px; letter-spacing: -.03em; }
.note-item p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.7; }

.case-footer { display: flex; justify-content: space-between; gap: 24px; align-items: end; padding: 70px 0 48px; border-top: 1px solid var(--line); }
.case-footer h2 { max-width: 580px; margin: 0; font-size: clamp(35px, 4.5vw, 62px); line-height: 1.12; letter-spacing: -.045em; }
.case-footer a { display: inline-flex; padding-bottom: 8px; border-bottom: 1px solid var(--ink); font-size: 13px; white-space: nowrap; }
.case-footer a:hover { color: var(--accent); border-color: var(--accent); }
.case-footer small { display: block; margin-top: 17px; color: var(--muted); font: 10px ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .08em; }

@media (max-width: 820px) {
  .case-page { width: min(100% - 40px, var(--max)); }
  .site-nav { padding: 18px 0; }
  .site-nav__links { gap: 14px; font-size: 12px; }
  .case-hero { grid-template-columns: 1fr; gap: 36px; padding: 62px 0 58px; }
  .case-hero h1 { font-size: clamp(44px, 11vw, 64px); }
  .hero-media { margin: 0 -4px; }
  .hero-video { width: min(100%, 320px); }
  .section { padding: 64px 0; }
  .section-head { grid-template-columns: 50px 1fr; gap: 14px; margin-bottom: 30px; }
  .intro-grid, .notes-grid { grid-template-columns: 1fr; gap: 32px; }
  .process-grid { grid-template-columns: repeat(2, 1fr); }
  .process-step { min-height: 180px; padding: 16px 14px 18px 0; }
  .process-step + .process-step { padding-left: 14px; }
  .process-step:nth-child(2n) { border-right: 0; }
  .process-step:nth-child(n+3) { border-top: 1px solid var(--line); }
  .process-step h3 { margin-top: 34px; }
  .examples { margin-left: -20px; margin-right: -20px; padding: 64px 20px 72px; }
  .examples-intro { margin: -8px 0 34px 64px; }
  .example-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 34px 18px; }
  .example-media video { width: min(100%, 300px); }
  .case-footer { display: grid; grid-template-columns: 1fr; align-items: start; padding-top: 54px; }
}

@media (min-width: 821px) and (max-width: 980px) {
  .example-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 40px 24px; }
  .example-media video { width: min(100%, 300px); }
}

@media (max-width: 560px) {
  .example-grid { grid-template-columns: 1fr; gap: 40px; }
  .example-media video { width: min(100%, 280px); }
  .example-card > p { max-width: 420px; }
}

@media (max-width: 480px) {
  .site-nav__links a:nth-child(2) { display: none; }
  .hero-lead { font-size: 16px; }
  .hero-note { right: -5px; min-width: 140px; }
  .meta-grid { gap: 18px; }
  .example-details { gap: 12px; }
  .example-card h3 { font-size: 27px; }
}

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