/* =========================================================
   游咔网址指南 / shared site kit  →  /assets/site.css
   查询地图语言：纸面网格底 + 炭黑命令横带 + 玻璃索引带
   ========================================================= */

/* ---------- 1. reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body { margin: 0; }

h1, h2, h3, h4, h5, p, figure, blockquote, ul, ol, dl, dd { margin: 0; }

ul, ol { padding: 0; list-style: none; }

a { color: inherit; text-decoration: none; }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

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

table { border-collapse: collapse; }

kbd { font: inherit; }

/* ---------- 2. tokens ---------- */
:root {
  --c-sand: #F4EBDD;
  --c-ochre: #B57945;
  --c-ink: #17130E;
  --c-green: #0B7A5A;
  --c-amber: #D98A2B;
  --c-indigo: #2C4D8A;
  --c-glass: #FFFFFFB3;
  --c-line: #D9CDBB;
  --c-deep: #6B4E32;
  --c-cool: #3F6B5E;

  --font-head: "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "HarmonyOS Sans SC", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", SFMono-Regular, "SF Mono", Consolas, monospace;

  --page-max: 1180px;
  --gutter: clamp(16px, 4vw, 40px);
  --radius: 3px;
  --shadow-card: 6px 6px 0 rgba(181, 121, 69, 0.18);
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ---------- 3. base typography ---------- */
body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--c-ink);
  background-color: var(--c-sand);
  background-image:
    linear-gradient(rgba(23, 19, 14, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 19, 14, 0.045) 1px, transparent 1px);
  background-size: 56px 56px;
  background-position: center top;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.01em;
}

.yk-h1 { font-size: clamp(2.6rem, 6vw, 5.6rem); }
.yk-h2 { font-size: clamp(1.6rem, 3.4vw, 2.6rem); }
.yk-h3 { font-size: clamp(1.25rem, 1.8vw, 1.5rem); }

.yk-lead {
  font-size: clamp(1.05rem, 1.5vw, 1.25rem);
  line-height: 1.7;
  color: var(--c-deep);
  max-width: 34em;
}

.yk-note {
  font-size: 12.5px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--c-deep);
}

.yk-mono {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-deep);
}

.yk-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  color: var(--c-deep);
  text-transform: uppercase;
}

.yk-eyebrow::before {
  content: "";
  width: 9px;
  height: 9px;
  flex: 0 0 auto;
  background: var(--c-ochre);
}

/* ---------- 4. layout utilities ---------- */
.yk-wrap {
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.yk-section { padding-block: clamp(40px, 7vw, 88px); }

.yk-section--tight { padding-block: clamp(24px, 4vw, 48px); }

.yk-grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}

.yk-grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.yk-grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.yk-divider {
  height: 0;
  border: 0;
  border-top: 1px dashed var(--c-ochre);
  opacity: 0.65;
  margin-block: clamp(24px, 4vw, 48px);
}

.yk-version {
  font-family: var(--font-mono);
  font-size: clamp(3.4rem, 11vw, 8.5rem);
  line-height: 0.85;
  letter-spacing: -0.04em;
  color: var(--c-sand);
  -webkit-text-stroke: 2px var(--c-ochre);
  text-shadow: none;
  user-select: none;
}

/* ---------- 5. buttons ---------- */
.yk-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1px solid transparent;
  border-radius: 2px;
  font-family: var(--font-head);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.4;
  white-space: nowrap;
  transition: background-color 0.18s var(--ease), color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.yk-btn--primary {
  background: var(--c-green);
  color: #F7F3EC;
  border-color: var(--c-green);
}

.yk-btn--primary:hover { background: #096348; border-color: #096348; }

.yk-btn--ghost {
  background: rgba(255, 255, 255, 0.5);
  color: var(--c-ink);
  border-color: var(--c-ink);
}

.yk-btn--ghost:hover { background: var(--c-ink); color: var(--c-sand); }

.yk-btn--onink {
  background: transparent;
  color: var(--c-sand);
  border-color: rgba(244, 235, 221, 0.55);
}

.yk-btn--onink:hover {
  background: var(--c-sand);
  color: var(--c-ink);
  border-color: var(--c-sand);
}

/* ---------- 6. labels / tags ---------- */
.yk-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 1px solid var(--c-ochre);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.55);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-deep);
}

.yk-tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 4px 9px;
  border: 1px solid var(--c-line);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.62);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--c-ink);
}

.yk-tag::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-cool);
}

.yk-tag--green { border-color: rgba(11, 122, 90, 0.45); }
.yk-tag--green::before { background: var(--c-green); }

.yk-tag--amber { border-color: rgba(217, 138, 43, 0.55); }
.yk-tag--amber::before { background: var(--c-amber); }

.yk-tag--indigo { border-color: rgba(44, 77, 138, 0.45); }
.yk-tag--indigo::before { background: var(--c-indigo); }

/* ---------- 7. surfaces ---------- */
.yk-card {
  position: relative;
  padding: clamp(16px, 2.4vw, 26px);
  border: 1px solid var(--c-line);
  border-top: 3px solid var(--c-ochre);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.7);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.yk-panel {
  padding: clamp(16px, 2.4vw, 26px);
  border: 1px solid var(--c-ink);
  border-left: 4px solid var(--c-green);
  border-radius: var(--radius);
  background: var(--c-sand);
  box-shadow: var(--shadow-card);
}

.yk-glass {
  padding: clamp(14px, 2vw, 22px);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: var(--c-glass);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

/* ---------- 8. index strip ---------- */
.yk-index-strip {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding: 12px 2px 16px;
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
  scroll-snap-type: x proximity;
  scrollbar-width: thin;
  cursor: grab;
  -webkit-overflow-scrolling: touch;
}

.yk-index-strip[data-dragging="true"] {
  cursor: grabbing;
  scroll-snap-type: none;
  user-select: none;
}

.yk-index-strip::-webkit-scrollbar { height: 6px; }
.yk-index-strip::-webkit-scrollbar-track { background: transparent; }
.yk-index-strip::-webkit-scrollbar-thumb {
  background: var(--c-line);
  border-radius: 6px;
}

.yk-index-strip__item {
  flex: 0 0 auto;
  scroll-snap-align: start;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--c-line);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.62);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--c-ink);
  white-space: nowrap;
  transition: border-color 0.18s var(--ease), background-color 0.18s var(--ease), color 0.18s var(--ease);
}

.yk-index-strip__item:hover {
  border-color: var(--c-ochre);
  color: var(--c-deep);
}

.yk-index-strip__item[aria-current="true"] {
  background: var(--c-ink);
  border-color: var(--c-ink);
  color: var(--c-sand);
}

/* ---------- 9. breadcrumb ---------- */
.yk-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
  padding-block: 14px 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--c-deep);
}

.yk-crumbs__item { display: inline-flex; align-items: center; }

.yk-crumbs__item + .yk-crumbs__item::before {
  content: "/";
  margin-inline: 8px;
  color: var(--c-ochre);
}

.yk-crumbs__link { color: var(--c-deep); border-bottom: 1px solid transparent; }
.yk-crumbs__link:hover { color: var(--c-ink); border-bottom-color: var(--c-ochre); }

/* ---------- 10. toc ---------- */
.yk-toc {
  display: grid;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
}

.yk-toc__link {
  display: block;
  padding: 7px 10px;
  border-left: 2px solid var(--c-line);
  color: var(--c-deep);
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.yk-toc__link:hover {
  border-left-color: var(--c-ochre);
  color: var(--c-ink);
}

.yk-toc__link[aria-current="true"] {
  border-left-color: var(--c-green);
  background: rgba(255, 255, 255, 0.62);
  color: var(--c-ink);
}

/* ---------- 11. figure / media ---------- */
.yk-figure {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.55);
}

.yk-figure__media {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background-color: var(--c-line);
  background-image:
    repeating-linear-gradient(45deg, rgba(23, 19, 14, 0.07) 0 2px, transparent 2px 11px),
    linear-gradient(160deg, rgba(244, 235, 221, 0.95), rgba(217, 205, 187, 0.95));
}

.yk-figure__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.yk-figure__cap {
  padding: 10px 12px;
  border-top: 1px solid var(--c-line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--c-deep);
}

.yk-figure--wide .yk-figure__media { aspect-ratio: 21 / 9; }
.yk-figure--tall .yk-figure__media { aspect-ratio: 4 / 5; }

/* ---------- 12. reveal ---------- */
.yk-reveal { transition: opacity 0.5s var(--ease), transform 0.5s var(--ease); }

.yk-reveal[data-reveal-ready] {
  opacity: 0;
  transform: translateY(12px);
}

.yk-reveal[data-visible="true"] {
  opacity: 1;
  transform: none;
}

/* ---------- 13. skip link ---------- */
.yk-skip {
  position: absolute;
  left: 12px;
  top: -72px;
  z-index: 200;
  padding: 10px 16px;
  border-radius: 2px;
  background: var(--c-ink);
  color: var(--c-sand);
  font-family: var(--font-head);
  font-size: 14px;
  font-weight: 700;
  transition: top 0.2s var(--ease);
}

.yk-skip:focus { top: 10px; }

/* ---------- 14. header ---------- */
.yk-header {
  position: sticky;
  top: 0;
  z-index: 90;
}

.yk-header__meta {
  background: var(--c-ink);
  color: var(--c-sand);
}

.yk-meta__inner {
  display: flex;
  align-items: center;
  gap: clamp(10px, 2vw, 24px);
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding: 7px var(--gutter);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  line-height: 1.6;
}

.yk-meta__line { color: rgba(244, 235, 221, 0.86); }

.yk-meta__badge {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 2px 8px;
  border: 1px solid rgba(244, 235, 221, 0.28);
  border-radius: 2px;
  color: var(--c-sand);
  white-space: nowrap;
}

.yk-meta__badge::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-amber);
}

.yk-meta__hint {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  color: rgba(244, 235, 221, 0.72);
  white-space: nowrap;
}

.yk-kbd {
  display: inline-block;
  padding: 2px 5px;
  border: 1px solid rgba(244, 235, 221, 0.42);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 10px;
  line-height: 1.2;
  color: var(--c-sand);
}

.yk-bar {
  position: relative;
  background: rgba(244, 235, 221, 0.88);
  border-bottom: 1px solid var(--c-ink);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
}

.yk-bar__inner {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding: 10px var(--gutter);
}

.yk-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.yk-brand__mark {
  position: relative;
  width: 26px;
  height: 26px;
  flex: 0 0 auto;
  border: 2px solid var(--c-ochre);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.6);
}

.yk-brand__mark::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 4px;
  width: 8px;
  height: 8px;
  background: var(--c-green);
}

.yk-brand__mark::after {
  content: "";
  position: absolute;
  right: 4px;
  bottom: 4px;
  width: 6px;
  height: 6px;
  border-right: 2px solid var(--c-ink);
  border-bottom: 2px solid var(--c-ink);
}

.yk-brand__text { display: block; }

.yk-brand__name {
  display: block;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--c-ink);
}

.yk-brand__sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 9.5px;
  line-height: 1.4;
  letter-spacing: 0.2em;
  color: var(--c-deep);
}

.yk-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
  min-width: 0;
}

.yk-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
  flex-wrap: nowrap;
}

.yk-nav__item { flex: 0 0 auto; }

.yk-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 10px;
  border: 1px solid transparent;
  border-radius: 2px;
  font-family: var(--font-body);
  font-size: 14.5px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--c-ink);
  white-space: nowrap;
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.yk-nav__idx {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 0.1em;
  color: var(--c-ochre);
}

.yk-nav__link:hover {
  border-color: var(--c-ochre);
  background: rgba(255, 255, 255, 0.6);
}

.yk-nav__link[aria-current="page"] {
  background: var(--c-ink);
  border-color: var(--c-ink);
  color: var(--c-sand);
}

.yk-nav__link[aria-current="page"] .yk-nav__idx { color: var(--c-amber); }

.yk-nav__link:focus-visible {
  outline: 2px solid var(--c-indigo);
  outline-offset: 2px;
}

.yk-bar__actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  margin-left: auto;
}

.yk-burger {
  display: none;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--c-ink);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.55);
  color: var(--c-ink);
}

.yk-burger__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: background-color 0.2s var(--ease);
}

.yk-burger__bars::before,
.yk-burger__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform 0.22s var(--ease), top 0.22s var(--ease);
}

.yk-burger__bars::before { top: -6px; }
.yk-burger__bars::after { top: 6px; }

.yk-burger[aria-expanded="true"] .yk-burger__bars { background: transparent; }

.yk-burger[aria-expanded="true"] .yk-burger__bars::before {
  top: 0;
  transform: rotate(45deg);
}

.yk-burger[aria-expanded="true"] .yk-burger__bars::after {
  top: 0;
  transform: rotate(-45deg);
}

.yk-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--c-green) 0%, var(--c-amber) 60%, var(--c-indigo) 100%);
  pointer-events: none;
}

/* ---------- 15. footer ---------- */
.yk-footer {
  margin-top: clamp(48px, 8vw, 96px);
  border-top: 3px solid var(--c-ochre);
  background: var(--c-ink);
  color: var(--c-sand);
}

.yk-footer__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 2fr) minmax(0, 1.05fr);
  gap: clamp(24px, 4vw, 56px);
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding: clamp(32px, 5vw, 64px) var(--gutter) clamp(24px, 4vw, 44px);
}

.yk-footer__brand { display: grid; gap: 12px; align-content: start; }

.yk-footer__logo {
  font-family: var(--font-head);
  font-size: clamp(1.35rem, 2.4vw, 1.9rem);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.yk-footer__tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: rgba(244, 235, 221, 0.72);
}

.yk-footer__meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: rgba(244, 235, 221, 0.85);
}

.yk-footer__brand .yk-btn { justify-self: start; margin-top: 4px; }

.yk-footer__nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 3vw, 32px);
  align-content: start;
}

.yk-fgroup__title {
  padding-bottom: 8px;
  margin-bottom: 12px;
  border-bottom: 1px solid rgba(244, 235, 221, 0.18);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--c-amber);
}

.yk-fgroup__list { display: grid; gap: 8px; }

.yk-fgroup__link {
  display: inline-block;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  font-size: 14.5px;
  color: rgba(244, 235, 221, 0.86);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.yk-fgroup__link:hover {
  color: #FFFFFF;
  border-bottom-color: var(--c-green);
}

.yk-footer__contact { display: grid; gap: 10px; align-content: start; }

.yk-contact__item {
  display: grid;
  gap: 2px;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(244, 235, 221, 0.2);
}

.yk-contact__key {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: rgba(244, 235, 221, 0.55);
}

.yk-contact__val {
  font-size: 13.5px;
  line-height: 1.6;
  color: rgba(244, 235, 221, 0.92);
  overflow-wrap: anywhere;
}

.yk-footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 24px;
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding: 16px var(--gutter) 28px;
  border-top: 1px solid rgba(244, 235, 221, 0.15);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: rgba(244, 235, 221, 0.62);
}

.yk-footer__legal { color: rgba(244, 235, 221, 0.78); }

.yk-footer :focus-visible {
  outline: 2px solid var(--c-amber);
  outline-offset: 3px;
}

/* ---------- 16. focus ---------- */
:focus-visible {
  outline: 2px solid var(--c-indigo);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 17. responsive ---------- */
@media (max-width: 1023px) {
  .yk-burger { display: inline-flex; }

  .yk-nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    z-index: 95;
    flex-direction: column;
    justify-content: flex-start;
    padding: 10px var(--gutter) 18px;
    border-bottom: 1px solid var(--c-ink);
    background: rgba(244, 235, 221, 0.97);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
    box-shadow: 0 18px 40px rgba(23, 19, 14, 0.18);
  }

  .yk-nav[data-open="true"] { display: block; }

  .yk-nav__list {
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 2px;
  }

  .yk-nav__link {
    width: 100%;
    justify-content: flex-start;
    padding: 12px 10px;
    border-bottom: 1px solid var(--c-line);
    font-size: 16px;
  }

  .yk-nav__link:hover { border-color: var(--c-line); }

  .yk-footer__inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr);
  }

  .yk-footer__contact { grid-column: 1 / -1; grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .yk-meta__hint { display: none; }

  .yk-grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 720px) {
  body { background-size: 40px 40px; }

  .yk-bar__inner { gap: 10px; padding: 9px var(--gutter); }

  .yk-bar__actions .yk-btn--primary { padding: 9px 12px; font-size: 13px; }

  .yk-footer__nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .yk-grid--2,
  .yk-grid--3 { grid-template-columns: minmax(0, 1fr); }

  .yk-footer__inner { grid-template-columns: minmax(0, 1fr); }

  .yk-footer__contact { grid-template-columns: minmax(0, 1fr); }

  .yk-footer__base { gap: 6px 14px; font-size: 11px; }

  .yk-lead { font-size: 1.02rem; }
}

@media (max-width: 520px) {
  .yk-header__meta { display: none; }

  .yk-brand__name { font-size: 15.5px; }

  .yk-brand__sub { font-size: 9px; letter-spacing: 0.16em; }

  .yk-bar__actions .yk-btn--primary { display: none; }

  .yk-version { -webkit-text-stroke-width: 1.5px; }
}

/* ---------- 18. reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .yk-reveal,
  .yk-reveal[data-reveal-ready] {
    opacity: 1;
    transform: none;
  }

  .yk-progress { transition: none; }
}