@charset "utf-8";

:root {
  --ink: #000000;
  --paper: #ffffff;
  --hair: rgba(0, 0, 0, 0.16);
  --hair-2: rgba(0, 0, 0, 0.08);
  --glass: rgba(255, 255, 255, 0.62);
  --radius: 10px;
  --shell: 1200px;
  --stack: 'Plus Jakarta Sans', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, -apple-system, 'Segoe UI', sans-serif;
}

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

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

body {
  margin: 0;
  overflow-x: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--stack);
  font-size: 17px;
  line-height: 1.72;
  font-weight: 400;
  letter-spacing: 0.004em;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.018em;
  overflow-wrap: break-word;
}

p {
  margin: 0 0 1.05em;
  max-width: 68ch;
  overflow-wrap: break-word;
}

ul,
ol {
  margin: 0 0 1.1em;
  padding-left: 1.25em;
}

li {
  margin: 0.35em 0;
}

hr {
  border: 0;
  height: 2px;
  width: 64px;
  background: var(--ink);
  margin: 0.55rem 0 1.9rem;
}

::selection {
  background: #000;
  color: #fff;
}

:focus-visible {
  outline: 3px solid #000;
  outline-offset: 3px;
}

[id] {
  scroll-margin-top: 26px;
}

.skip {
  position: absolute;
  left: 12px;
  top: -60px;
  z-index: 40;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 18px;
  background: #000;
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius);
  font-size: 16px;
  transition: top 0.2s ease;
}

.skip:focus {
  top: 12px;
}

/* ---------- 顶部细条 ---------- */

.ticker {
  background: var(--ink);
  color: #fff;
  font-size: 16px;
  letter-spacing: 0.03em;
  overflow: hidden;
}

.ticker span {
  display: block;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 8px 20px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ---------- 品牌行 ---------- */

.masthead {
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 2px solid var(--ink);
}

@supports (backdrop-filter: blur(2px)) {
  .masthead {
    backdrop-filter: blur(12px) saturate(1.1);
  }
}

.brandrow {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 20px;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 12px 20px 8px;
  min-width: 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  min-height: 44px;
  text-decoration: none;
}

.brand .mark {
  width: 36px;
  height: 36px;
  flex: 0 0 36px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0;
  overflow: hidden;
}

.brand .mark img {
  width: 36px;
  height: 36px;
  max-width: 36px;
  object-fit: cover;
}

.brandname {
  font-size: 21px;
  font-weight: 700;
  letter-spacing: -0.02em;
  min-width: 0;
  overflow-wrap: break-word;
}

.brandline {
  margin: 0;
  font-size: 16px;
  line-height: 1.5;
  color: rgba(0, 0, 0, 0.72);
  max-width: 46ch;
  min-width: 0;
}

/* ---------- 菜单行（分组竖排） ---------- */

.menubar {
  border-top: 1px solid var(--hair-2);
  min-width: 0;
}

.menubar nav {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
  min-width: 0;
}

.navlist {
  display: flex;
  gap: 2px;
  list-style: none;
  margin: 0;
  padding: 0;
  overflow-x: auto;
  max-width: 100%;
  scrollbar-width: thin;
}

.navlist li {
  flex: 0 0 auto;
  margin: 0;
}

.navlist a {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 46px;
  padding: 11px 13px;
  font-size: 16px;
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  border-radius: var(--radius);
  transition: background 0.18s ease, color 0.18s ease;
}

.navlist .n {
  font-size: 16px;
  font-weight: 700;
  opacity: 0.45;
}

.navlist a:hover,
.navlist a:focus-visible {
  background: var(--ink);
  color: #fff;
}

.navlist a:hover .n,
.navlist a:focus-visible .n {
  opacity: 0.7;
}

/* ---------- 主体栅格：左栏 + 正文 ---------- */

.shell {
  display: grid;
  grid-template-columns: 236px minmax(0, 1fr);
  align-items: start;
  gap: clamp(24px, 3.4vw, 52px);
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(22px, 3.4vw, 44px) 20px clamp(36px, 5vw, 72px);
  min-width: 0;
  background-image: radial-gradient(rgba(0, 0, 0, 0.11) 1px, transparent 1px);
  background-size: 22px 22px;
}

.shell > * {
  min-width: 0;
}

main {
  min-width: 0;
}

div {
  min-width: 0;
}

/* ---------- 左栏 ---------- */

.rail {
  display: grid;
  gap: 16px;
  align-content: start;
  min-width: 0;
}

.rail-card {
  background: var(--glass);
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  padding: 16px 14px;
  min-width: 0;
}

@supports (backdrop-filter: blur(2px)) {
  .rail-card {
    backdrop-filter: blur(12px) saturate(1.15);
  }
}

.rail-title {
  font-size: 16px;
  letter-spacing: 0.16em;
}

.rail-card hr {
  width: 32px;
  height: 2px;
  margin: 0.5rem 0 0.9rem;
}

.rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  max-width: 100%;
  overflow-x: auto;
  scrollbar-width: thin;
}

.rail-list li {
  margin: 0;
  border-top: 1px solid var(--hair-2);
}

.rail-list li:first-child {
  border-top: 0;
}

.rail-list a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  min-height: 44px;
  padding: 10px 2px;
  font-size: 16px;
  line-height: 1.4;
  text-decoration: none;
}

.rail-list .n {
  font-size: 16px;
  font-weight: 700;
  opacity: 0.4;
}

.rail-list a:hover .t,
.rail-list a:focus-visible .t {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.rail-note {
  margin: 0;
  font-size: 16px;
  line-height: 1.6;
  color: rgba(0, 0, 0, 0.7);
  padding: 0 2px;
  max-width: none;
}

/* ---------- 首屏 ---------- */

.hero {
  display: grid;
  grid-template-columns: 1.06fr 0.94fr;
  align-items: center;
  gap: clamp(20px, 3vw, 44px);
  min-height: 70vh;
  padding: clamp(14px, 2.4vw, 30px) 0 clamp(26px, 4vw, 46px);
  min-width: 0;
}

.hero-copy {
  text-align: center;
  min-width: 0;
}

.kicker {
  margin: 0 0 14px;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.24em;
  color: rgba(0, 0, 0, 0.7);
  max-width: none;
}

.hero h1 {
  margin: 0 0 18px;
  font-size: clamp(2rem, 4.6vw, 3.4rem);
  line-height: 1.05;
  letter-spacing: -0.032em;
}

.hero-lede {
  margin: 0 auto 22px;
  max-width: 40ch;
  font-size: clamp(1.02rem, 1.35vw, 1.14rem);
  line-height: 1.72;
  color: rgba(0, 0, 0, 0.78);
}

.hero-lede::first-letter {
  float: left;
  font-size: 3.4em;
  line-height: 0.8;
  padding: 0.05em 0.1em 0 0;
  font-weight: 700;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 24px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.18s ease, color 0.18s ease, transform 0.15s ease;
}

.btn:active {
  transform: translateY(1px);
}

.btn-solid {
  background: var(--ink);
  color: #fff;
}

.btn-solid:hover,
.btn-solid:focus-visible {
  background: #fff;
  color: var(--ink);
}

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

.btn-ghost:hover,
.btn-ghost:focus-visible {
  background: var(--ink);
  color: #fff;
}

.hero-figure {
  margin: 0;
  min-width: 0;
}

.hero-shot,
.hero-frame {
  width: 100%;
  max-width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(0, 0, 0, 0.06), rgba(0, 0, 0, 0.015));
}

.hero-frame {
  background-image: radial-gradient(rgba(0, 0, 0, 0.26) 1px, transparent 1px);
  background-size: 14px 14px;
}

.hero-figure figcaption {
  margin-top: 10px;
  padding-top: 9px;
  border-top: 1px solid var(--hair);
  font-size: 16px;
  color: rgba(0, 0, 0, 0.66);
}

/* ---------- 正文标签与引文 ---------- */

.bodylabel {
  font-size: clamp(1.1rem, 1.8vw, 1.3rem);
  letter-spacing: 0.06em;
  margin: 0;
}

.pull {
  margin: 0 0 clamp(24px, 3.6vw, 44px);
  padding: 4px 0 4px 20px;
  border-left: 6px solid var(--ink);
  font-size: clamp(1.1rem, 1.9vw, 1.4rem);
  line-height: 1.5;
  font-weight: 600;
  max-width: 52ch;
}

/* ---------- 正文分区 ---------- */

.content {
  counter-reset: sec;
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  min-width: 0;
  overflow-wrap: break-word;
}

.content > article {
  counter-increment: sec;
  position: relative;
  min-width: 0;
  padding-top: clamp(22px, 3vw, 34px);
  border-top: 3px solid var(--ink);
}

.content > article::before {
  content: counter(sec, decimal-leading-zero);
  position: absolute;
  top: -0.85em;
  right: 0;
  padding: 0 0.45em;
  background: var(--paper);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.content h2 {
  font-size: clamp(1.4rem, 2.6vw, 1.95rem);
  margin: 0 0 0.15em;
  letter-spacing: -0.02em;
}

.content h3 {
  font-size: clamp(1.14rem, 1.8vw, 1.32rem);
  margin: 1.5em 0 0.3em;
}

.content h2 + hr,
.content h3 + hr {
  width: 100%;
  height: 1px;
  background: var(--hair);
  margin: 0.75rem 0 1.3rem;
}

.content a {
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 2px;
}

.content strong {
  font-weight: 700;
}

.content ul,
.content ol {
  padding-left: 1.35em;
}

.content ul li::marker {
  font-weight: 700;
}

.content figure {
  margin: 1.5em 0;
  max-width: 100%;
}

.content img {
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  max-width: 100%;
}

.content figcaption {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--hair);
  font-size: 16px;
  color: rgba(0, 0, 0, 0.66);
}

.content blockquote {
  margin: 1.6em 0;
  padding: 16px 18px;
  border-left: 6px solid var(--ink);
  border-radius: 0 var(--radius) var(--radius) 0;
  background: var(--glass);
  font-size: 1.05rem;
}

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

.content table {
  width: 100%;
  max-width: 100%;
  border-collapse: collapse;
  margin: 1.4em 0;
  font-size: 16px;
}

.content th,
.content td {
  padding: 10px 8px;
  text-align: left;
  border-bottom: 1px solid var(--hair);
  overflow-wrap: break-word;
}

.content th {
  border-bottom: 2px solid var(--ink);
  font-weight: 700;
}

.content code {
  font-size: 16px;
  padding: 1px 5px;
  border-radius: 4px;
  background: rgba(0, 0, 0, 0.07);
  overflow-wrap: break-word;
}

/* ---------- 结尾大块 ---------- */

.cta {
  margin-top: clamp(34px, 5vw, 64px);
  padding: clamp(26px, 4vw, 48px) clamp(20px, 4vw, 40px);
  border-radius: var(--radius);
  background: var(--ink);
  color: #fff;
  text-align: center;
  min-width: 0;
}

.cta h2 {
  font-size: clamp(1.45rem, 3vw, 2.1rem);
  margin: 0;
}

.cta hr {
  width: 56px;
  height: 2px;
  background: #fff;
  margin: 0.8rem auto 1.2rem;
}

.cta p {
  margin: 0 auto 1.5em;
  max-width: 44ch;
  color: rgba(255, 255, 255, 0.86);
}

.cta .btn {
  border-color: #fff;
  background: #fff;
  color: var(--ink);
}

.cta .btn:hover,
.cta .btn:focus-visible {
  background: transparent;
  color: #fff;
}

/* ---------- 页脚 ---------- */

footer {
  margin-top: clamp(30px, 4vw, 56px);
  border-top: 2px solid var(--ink);
  padding: 26px 20px 44px;
  text-align: center;
}

footer p {
  margin: 0 auto 6px;
  max-width: none;
  font-size: 16px;
  font-weight: 600;
}

footer small {
  display: block;
  margin: 0 auto;
  max-width: 52ch;
  font-size: 16px;
  line-height: 1.6;
  color: rgba(0, 0, 0, 0.68);
}

/* ---------- 入场 ---------- */

html.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

html.js .reveal.in {
  opacity: 1;
  transform: none;
}

html.js .rail-list li:nth-child(2) { transition-delay: 0.04s; }
html.js .rail-list li:nth-child(3) { transition-delay: 0.08s; }
html.js .rail-list li:nth-child(4) { transition-delay: 0.12s; }
html.js .rail-list li:nth-child(5) { transition-delay: 0.16s; }
html.js .rail-list li:nth-child(6) { transition-delay: 0.2s; }
html.js .rail-list li:nth-child(7) { transition-delay: 0.24s; }

/* ---------- 断点 ---------- */

@media (max-width: 1000px) {
  .shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .rail-card {
    padding: 12px 12px 8px;
  }

  .rail-card hr {
    display: none;
  }

  .rail-title {
    display: none;
  }

  .rail-list {
    display: flex;
    gap: 0;
  }

  .rail-list li {
    flex: 0 0 auto;
    border-top: 0;
    border-left: 1px solid var(--hair-2);
  }

  .rail-list li:first-child {
    border-left: 0;
  }

  .rail-list a {
    gap: 7px;
    padding: 10px 12px;
    white-space: nowrap;
  }

  .rail-note {
    display: none;
  }

  .hero {
    grid-template-columns: minmax(0, 1fr);
    min-height: 0;
  }
}

@media (max-width: 720px) {
  body {
    font-size: 17px;
  }

  .brandrow {
    padding: 10px 16px 6px;
  }

  .brandline {
    width: 100%;
    font-size: 16px;
  }

  .menubar nav {
    padding: 0 12px;
  }

  .shell {
    padding: 16px 16px 40px;
  }

  .hero h1 {
    font-size: clamp(1.85rem, 8.4vw, 2.4rem);
  }

  .hero-lede {
    max-width: 34ch;
  }

  .hero-figure figcaption {
    font-size: 16px;
  }

  .content > article::before {
    font-size: 16px;
  }

  .cta {
    text-align: left;
  }

  .cta hr {
    margin-left: 0;
  }

  .cta p {
    margin-left: 0;
  }
}

@media (max-width: 420px) {
  .brandname {
    font-size: 19px;
  }

  .hero-actions .btn {
    padding: 12px 18px;
  }
}

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

  html.js .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

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

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