* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: #fff;
  color: #000;
  font-family: "Space Grotesk", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: #000; }
:focus-visible { outline: 3px solid #000; outline-offset: 3px; }

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

/* ---------- 顶栏 ---------- */
.masthead {
  position: sticky;
  top: 0;
  z-index: 30;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: .55rem .9rem;
  padding: .65rem 1rem;
  background: #fff;
  border-bottom: 3px solid #000;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  min-height: 44px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -.03em;
  white-space: nowrap;
}

.brand .mark {
  display: block;
  flex: none;
  width: 22px;
  height: 22px;
  background: #000;
  border: 3px solid #000;
  box-shadow: inset 0 0 0 3px #fff;
}

.brand:hover .mark { background: #fff; }

.dock {
  grid-column: 1 / -1;
  order: 3;
  display: flex;
  gap: .4rem;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: none;
  padding-bottom: .12rem;
}

.dock::-webkit-scrollbar { display: none; }

.dock a {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  min-height: 44px;
  padding: .55rem .7rem;
  border: 3px solid #000;
  background: #fff;
  text-decoration: none;
  font-size: 1rem;
  line-height: 1.2;
  white-space: nowrap;
}

.dock a:hover,
.dock a:focus-visible { background: #000; color: #fff; }

.dock .ico {
  display: block;
  flex: none;
  width: 9px;
  height: 9px;
  background: #000;
}

.dock a:hover .ico { background: #fff; }
.dock a.out { display: none; }

.seek {
  display: flex;
  border: 3px solid #000;
  background: #fff;
  justify-self: end;
}

.seek input {
  width: 8rem;
  max-width: 40vw;
  min-height: 44px;
  padding: .45rem .6rem;
  border: 0;
  background: transparent;
  color: #000;
  font: inherit;
  font-size: 1rem;
}

.seek input:focus { outline: none; }
.seek:focus-within { box-shadow: 0 0 0 3px #000; }

.seek button {
  min-height: 44px;
  padding: 0 .8rem;
  border: 0;
  border-left: 3px solid #000;
  background: #000;
  color: #fff;
  font: inherit;
  font-weight: 700;
  font-size: 1rem;
  cursor: pointer;
}

.seek button:hover { background: #fff; color: #000; }

/* ---------- 大标题 ---------- */
.billboard {
  min-height: 70vh;
  display: grid;
  place-items: center;
  align-content: center;
  text-align: center;
  padding: 5rem 1.1rem;
  border-bottom: 3px solid #000;
  background-color: #fff;
  background-image: radial-gradient(#000 1.2px, transparent 1.2px);
  background-size: 16px 16px;
  scroll-margin-top: 7rem;
}

.billboard h1 {
  margin: 0;
  max-width: 22ch;
  font-size: clamp(3rem, 10vw, 12rem);
  font-weight: 900;
  line-height: .9;
  letter-spacing: -.05em;
  overflow-wrap: break-word;
}

.billboard .lede {
  margin: 1.7rem auto 0;
  max-width: 36ch;
  padding: .85rem 1.1rem;
  border: 3px solid #000;
  background: #fff;
  font-size: 1rem;
  line-height: 1.6;
}

/* ---------- 主体 ---------- */
main { display: block; }

.frame {
  max-width: 1180px;
  margin: 0 auto;
  padding: 3.5rem 1.1rem 5.5rem;
  display: grid;
  gap: 2.4rem;
}

.rail {
  border: 3px solid #000;
  padding: .95rem 1rem 1.1rem;
  background: #fff;
  align-self: start;
}

.rail-title {
  margin: 0 0 .7rem;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: .22em;
}

.rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.rail-list a {
  display: flex;
  align-items: center;
  gap: .65rem;
  min-height: 44px;
  padding: .35rem .1rem;
  border-top: 1px solid #000;
  text-decoration: none;
  font-size: 1rem;
  line-height: 1.3;
}

.rail-list a:hover { background: #000; color: #fff; }

.num {
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  flex: none;
}

.totop {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  margin-top: 1rem;
  border: 3px solid #000;
  background: #000;
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  font-size: 1rem;
}

.totop:hover { background: #fff; color: #000; }

.body { min-width: 0; overflow-wrap: break-word; }

.body > section {
  scroll-margin-top: 7rem;
  padding-top: 2.2rem;
  margin-top: 2.6rem;
  border-top: 3px solid #000;
}

.body > section:first-child {
  padding-top: 0;
  margin-top: 0;
  border-top: 0;
}

.body h2 {
  margin: 0 0 .8rem;
  font-size: clamp(1.9rem, 5.4vw, 3.4rem);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -.045em;
}

.body h3 {
  margin: 1.9rem 0 .6rem;
  font-size: clamp(1.35rem, 3vw, 1.9rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -.03em;
}

.body h2 + hr,
.body h3 + hr {
  height: 7px;
  border: 0;
  background: #000;
  margin: .2rem 0 1.6rem;
  width: 100%;
}

.body hr {
  height: 5px;
  border: 0;
  background: #000;
  margin: 1.6rem 0;
}

.body p {
  margin: 0 0 1.15rem;
  max-width: 64ch;
  font-size: 1.05rem;
}

.body ul,
.body ol {
  margin: 0 0 1.3rem;
  padding-left: 1.4rem;
  max-width: 64ch;
}

.body li { margin: 0 0 .5rem; font-size: 1.05rem; }

.body blockquote {
  margin: 1.6rem 0;
  padding: 1rem 1.2rem;
  border: 3px solid #000;
  font-size: 1.05rem;
}

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

.body figure { margin: 1.7rem 0; }

.body strong { font-weight: 700; }

.body a {
  text-decoration: none;
  border-bottom: 2px solid #000;
  font-weight: 700;
}

.body a:hover { background: #000; color: #fff; }

.body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.4rem 0;
  font-size: 1rem;
}

.body th,
.body td {
  border: 2px solid #000;
  padding: .55rem .65rem;
  text-align: left;
  vertical-align: top;
}

.body th { background: #000; color: #fff; font-weight: 700; }

.body code {
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  border: 2px solid #000;
  padding: 0 .3em;
  font-size: .95em;
}

.body pre {
  overflow-x: auto;
  border: 3px solid #000;
  padding: .9rem;
}

.body pre code { border: 0; padding: 0; }

.stamp {
  margin: 0;
  padding: 1.1rem .9rem;
  border: 3px solid #000;
  background: #000;
  color: #fff;
  text-align: center;
  transform: rotate(-2deg);
  align-self: start;
}

.stamp-mark {
  margin: 0;
  font-weight: 900;
  font-size: 1.1rem;
  line-height: 1.1;
  letter-spacing: -.04em;
  color: #fff;
}

/* ---------- 页脚 ---------- */
footer {
  border-top: 3px solid #000;
  background: #000;
  color: #fff;
  padding: 2.6rem 1.1rem 2.2rem;
  display: grid;
  gap: 2.2rem;
}

footer section { min-width: 0; }

footer h2 {
  margin: 0;
  color: #fff;
  font-weight: 900;
  font-size: clamp(1.8rem, 6vw, 3.2rem);
  line-height: .92;
  letter-spacing: -.05em;
}

footer hr {
  height: 5px;
  border: 0;
  background: #fff;
  margin: .75rem 0 .9rem;
}

footer .foot-title {
  margin: 0;
  color: #fff;
  font-size: 1rem;
  line-height: 1.5;
}

footer nav dl {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: .15rem 1rem;
  margin: 0;
}

footer dt {
  font-size: 1rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  opacity: .55;
}

footer dd { margin: 0; }

footer dd a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: .2rem .15rem;
  color: #fff;
  text-decoration: none;
  font-size: 1rem;
  border-bottom: 2px solid #000;
}

footer dd a:hover,
footer dd a:focus-visible {
  background: #fff;
  color: #000;
  border-bottom-color: #fff;
}

footer .foot-copy p {
  margin: 0;
  color: #fff;
  font-size: 1rem;
}

/* ---------- 揭示动效 ---------- */
.js .body > section,
.js .rail,
.js .stamp {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .55s ease, transform .6s cubic-bezier(.2, .7, .2, 1);
}

.js .stamp { transform: translateY(22px) rotate(-2deg); }

.js .body > section.in,
.js .rail.in {
  opacity: 1;
  transform: none;
}

.js .stamp.in {
  opacity: 1;
  transform: rotate(-2deg);
}

/* ---------- 断点 ---------- */
@media (min-width: 60rem) {
  .masthead {
    grid-template-columns: auto minmax(0, 1fr) auto;
    gap: 1.4rem;
    padding: .8rem 2rem;
  }

  .dock {
    grid-column: auto;
    order: 2;
    flex-wrap: wrap;
    overflow: visible;
  }

  .seek { justify-self: end; }
  .seek input { width: 10rem; max-width: none; }

  .frame {
    grid-template-columns: 205px minmax(0, 1fr);
    column-gap: 3.6rem;
    padding: 5rem 2rem 7rem;
  }

  .rail { grid-column: 1; grid-row: 1; }
  .body { grid-column: 2; grid-row: 1 / span 2; }
  .stamp { grid-column: 1; grid-row: 2; }
}

@media (min-width: 52rem) {
  footer {
    grid-template-columns: 1.1fr 1.4fr auto;
    align-items: start;
    padding: 3.2rem 2rem 2.2rem;
  }

  footer .foot-copy { text-align: right; }
}

@media (max-width: 26rem) {
  .brand { font-size: 1rem; }
  .billboard { padding: 3.6rem 1rem; }
  .billboard .lede { margin-top: 1.3rem; }
}
</｜DSML｜ parameter>
</｜DSML｜ invoke>
</｜DSML｜ calls>

button[aria-expanded]{min-width:44px;min-height:44px}