@import url('https://fonts.googleapis.com/css2?family=Cormorant:wght@400;500;600;700&family=Montserrat:wght@300;400;500;600;700&display=swap');

:root {
  --ink: #000000;
  --paper: #ffffff;
  --muted: #585858;
  --line: 1px solid #000000;
  --serif: "Cormorant", "Songti SC", "Noto Serif SC", "SimSun", Georgia, serif;
  --sans: "Montserrat", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --wrap: 1180px;
}

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  font-weight: 300;
  line-height: 1.75;
  letter-spacing: 0.01em;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; }
h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.1; margin: 0; }

/* 报头 */
.masthead {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--paper);
  border-bottom: 2px solid var(--ink);
}

.mast-bar {
  max-width: var(--wrap);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 8px 24px;
}

.brand {
  flex: 0 0 auto;
  font-family: var(--serif);
  font-size: 27px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.03em;
  text-decoration: none;
  padding: 10px 0;
}

.mast-nav {
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0 2px;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 9px;
  font-size: 16px;
  font-weight: 400;
  text-decoration: none;
  border-bottom: 2px solid transparent;
}

.nav-link:hover { border-bottom-color: var(--ink); }

.mast-cta {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  background: var(--ink);
  color: var(--paper);
  font-size: 16px;
  font-weight: 500;
  text-decoration: none;
  border-radius: 10px;
  border: 2px solid var(--ink);
}

.mast-cta:hover { background: var(--paper); color: var(--ink); }

.menu-btn { display: none; }

/* 骨架：左栏 + 正文 */
main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 208px minmax(0, 1fr);
  gap: 0 48px;
  align-items: start;
}

.rail {
  position: sticky;
  top: 84px;
  align-self: start;
  padding: 40px 20px 0 0;
  border-right: var(--line);
}

.rail small {
  display: block;
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--muted);
}

.rail-title { font-size: 22px; margin: 4px 0 14px; }

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

.rail-list li {
  counter-increment: rail;
  border-top: var(--line);
}

.rail-list a {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  padding: 4px 0;
  font-size: 16px;
  text-decoration: none;
}

.rail-list a::before {
  content: counter(rail, decimal-leading-zero);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.rail-list a:hover { color: var(--muted); }

/* 头版 */
.feature { min-width: 0; }

.hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
  align-items: end;
  min-height: 70vh;
  padding: 36px 0 44px;
}

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

.hero-collage {
  position: relative;
  min-height: 300px;
  align-self: stretch;
}

.shot {
  margin: 0;
  border: var(--line);
  border-radius: 10px;
  overflow: hidden;
  background: var(--paper);
}

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

.shot-a { position: absolute; left: 0; top: 4%; width: 78%; height: 74%; }
.shot-b { position: absolute; right: 0; bottom: 2%; width: 62%; height: 50%; }

.hero-words { text-align: right; }

.kicker {
  margin: 0 0 12px;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.26em;
  color: var(--muted);
}

.hero h1 {
  font-size: clamp(38px, 5.4vw, 76px);
  letter-spacing: -0.02em;
  line-height: 1.02;
}

.dek {
  margin: 20px 0 0 auto;
  max-width: 30em;
  font-size: 17px;
  color: var(--muted);
}

/* 正文区块 */
article > div[id] {
  scroll-margin-top: 100px;
  border-top: var(--line);
  margin-top: 34px;
  padding-top: 34px;
}

article small {
  display: block;
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--muted);
  margin-bottom: 8px;
}

article h2 {
  font-size: clamp(26px, 3.2vw, 40px);
  margin: 0 0 18px;
  letter-spacing: -0.01em;
}

article h3 { font-size: 23px; margin: 1.6em 0 0.5em; }

article p { margin: 0 0 1.15em; }

article ul,
article ol { margin: 0 0 1.15em; padding-left: 1.4em; }

article li { margin: 0.35em 0; }

article a { text-decoration: underline; text-underline-offset: 3px; }

article blockquote {
  margin: 1.7em 0;
  padding: 16px 24px;
  border-left: 4px solid var(--ink);
  font-family: var(--serif);
  font-size: 23px;
  line-height: 1.42;
}

article figure { margin: 1.7em 0; }

article figcaption {
  margin-top: 8px;
  font-size: 16px;
  color: var(--muted);
}

article img { border: var(--line); border-radius: 10px; }

article table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.2em;
  font-size: 16px;
}

article th,
article td {
  border-bottom: var(--line);
  padding: 10px 8px;
  text-align: left;
}

article code {
  font-size: 16px;
  border: var(--line);
  border-radius: 4px;
  padding: 0 4px;
}

article > div[id] > p:first-of-type::first-letter {
  float: left;
  font-family: var(--serif);
  font-size: 3.3em;
  line-height: 0.84;
  padding: 0.06em 0.12em 0 0;
}

/* 报尾 */
.colophon {
  max-width: var(--wrap);
  margin: 72px auto 0;
  padding: 40px 24px 26px;
  border-top: 2px solid var(--ink);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.8fr);
  gap: 26px 48px;
  align-items: start;
}

.foot-mark {
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1.1;
  text-decoration: none;
  display: inline-block;
  padding: 8px 0;
}

.foot-links dl { margin: 0; }

.foot-links dt {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--muted);
  margin-bottom: 4px;
}

.foot-links dd { display: inline-block; margin: 0 20px 0 0; }

.foot-links dd a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 16px;
  font-weight: 400;
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.foot-links dd a:hover { border-bottom-color: var(--ink); }

.foot-bar {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 10px 24px;
  margin-top: 18px;
  padding-top: 14px;
  border-top: var(--line);
}

.copy { margin: 0; font-size: 16px; color: var(--muted); }

.foot-bar-links { margin: 0; display: flex; gap: 20px; }

.foot-bar-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 16px;
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.foot-bar-links a:hover { border-bottom-color: var(--ink); }

/* 动效 */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}

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

/* 宽屏多栏 */
@media (min-width: 1100px) {
  article > div[id] {
    columns: 2;
    column-gap: 2.6rem;
    column-rule: var(--line);
  }
  article > div[id] > small,
  article > div[id] > h2 { column-span: all; }
}

@media (max-width: 1080px) {
  .menu-btn {
    display: inline-flex;
    align-items: center;
    margin-left: auto;
    min-height: 44px;
    padding: 0 14px;
    border: 2px solid var(--ink);
    border-radius: 10px;
    background: var(--paper);
    font-family: var(--sans);
    font-size: 16px;
    font-weight: 500;
    color: var(--ink);
    cursor: pointer;
  }

  .mast-nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin: 0;
    padding: 6px 18px 14px;
    background: var(--paper);
    border-bottom: 2px solid var(--ink);
    flex-direction: column;
    justify-content: flex-start;
  }

  .masthead.menu-open .mast-nav { display: flex; }

  .nav-link {
    width: 100%;
    min-height: 48px;
    padding: 0 2px;
    border-bottom: var(--line);
  }
}

@media (max-width: 900px) {
  .mast-bar { padding: 8px 16px; gap: 10px; }
  .brand { font-size: 22px; }
  .mast-cta { padding: 0 12px; font-size: 16px; }

  main { grid-template-columns: minmax(0, 1fr); padding: 0 16px; gap: 0; }

  .rail {
    position: static;
    border-right: 0;
    border-bottom: var(--line);
    padding: 18px 0 12px;
  }

  .rail-list {
    display: flex;
    overflow-x: auto;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .rail-list li {
    flex: 0 0 auto;
    border-top: 0;
    border-right: var(--line);
  }

  .rail-list a { padding: 0 12px; white-space: nowrap; }
  .rail-list a::before { content: none; }

  .hero {
    grid-template-columns: minmax(0, 1fr);
    min-height: 0;
    padding: 26px 0 30px;
    gap: 22px;
  }

  .hero-collage { order: 2; min-height: 220px; }

  .hero-words { text-align: left; }
  .dek { margin-left: 0; }

  article > div[id] { scroll-margin-top: 84px; margin-top: 26px; padding-top: 26px; }

  .colophon {
    grid-template-columns: minmax(0, 1fr);
    padding: 30px 16px 22px;
    gap: 22px;
  }

  .foot-bar { margin-top: 6px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .shot { transform: none !important; }
}

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