@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700;800&display=swap');

:root {
  --ink: #000000;
  --paper: #ffffff;
  --line: rgba(0, 0, 0, 0.16);
  --glass: rgba(255, 255, 255, 0.72);
  --r: 28px;
  --u: 8px;
  --pad: clamp(16px, 4vw, 44px);
  --shell: 1320px;
}

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

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

body {
  margin: 0;
  color: var(--ink);
  background-color: var(--paper);
  background-image: radial-gradient(rgba(0, 0, 0, 0.12) 1px, transparent 1px);
  background-size: 18px 18px;
  font-family: Inter, Helvetica, Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 17px;
  line-height: 1.62;
  font-weight: 400;
}

a {
  color: inherit;
}

:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: 16px;
  top: -70px;
  z-index: 90;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-weight: 700;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip:focus {
  top: 12px;
}

/* 顶部两行：品牌行 / 菜单行 */
.masthead {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--ink);
}

.mast-brand {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px var(--pad);
  max-width: var(--shell);
  margin: 0 auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 48px;
  font-size: 21px;
  font-weight: 800;
  letter-spacing: -0.035em;
  text-decoration: none;
}

.brand::before {
  content: "";
  flex: none;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink);
}

.mast-tools {
  display: flex;
  align-items: center;
  gap: 8px;
}

.tool {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--paper);
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
}

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

.burger {
  display: grid;
  place-content: center;
  gap: 5px;
  width: 46px;
  height: 46px;
  padding: 0;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--ink);
  cursor: pointer;
}

.burger span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--paper);
  transition: background 0.2s ease;
}

.burger[aria-expanded="true"] {
  background: var(--paper);
}

.burger[aria-expanded="true"] span {
  background: var(--ink);
}

.mast-nav {
  border-top: 1px solid var(--ink);
  overflow-x: auto;
  scrollbar-width: thin;
}

.mast-nav p {
  display: flex;
  gap: 2px;
  margin: 0;
  padding: 0 clamp(6px, 3vw, 28px);
}

.mast-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border-bottom: 3px solid transparent;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}

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

/* 全屏遮罩菜单 */
.dock {
  position: fixed;
  inset: 0;
  z-index: 70;
  display: grid;
  align-content: start;
  gap: 20px;
  padding: clamp(18px, 5vw, 56px);
  background: var(--ink);
  color: var(--paper);
  overflow-y: auto;
  visibility: hidden;
  opacity: 0;
  transform: translateY(-10px);
  transition: opacity 0.28s ease, transform 0.28s ease, visibility 0.28s;
}

.dock[data-open="true"] {
  visibility: visible;
  opacity: 1;
  transform: none;
}

.dock-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.dock-brand {
  margin: 0;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.03em;
}

.dock-close {
  min-height: 44px;
  padding: 0 18px;
  border: 1px solid var(--paper);
  border-radius: 999px;
  background: transparent;
  color: var(--paper);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.dock nav p {
  display: grid;
  margin: 0;
}

.dock nav a {
  display: flex;
  align-items: center;
  min-height: 56px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.24);
  color: var(--paper);
  font-size: clamp(20px, 4.4vw, 34px);
  font-weight: 800;
  letter-spacing: -0.035em;
  text-decoration: none;
  transition: padding 0.2s ease;
}

.dock nav a:hover {
  padding-left: 12px;
}

/* 首屏 */
.hero {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 16px;
  align-items: end;
  min-height: 70vh;
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(28px, 6vw, 72px) var(--pad) clamp(24px, 4vw, 52px);
  border-bottom: 1px solid var(--ink);
}

.hero-copy {
  grid-column: 1 / span 7;
  min-width: 0;
}

.hero-copy h1 {
  margin: 0 0 20px;
  font-size: clamp(36px, 6.2vw, 78px);
  font-weight: 800;
  line-height: 0.98;
  letter-spacing: -0.045em;
  max-width: 16ch;
}

.hero-lede {
  max-width: 46ch;
  margin: 0 0 26px;
  font-size: clamp(17px, 1.5vw, 20px);
  color: rgba(0, 0, 0, 0.72);
}

.hero-act {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  min-height: 50px;
  padding: 0 24px;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
}

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

.hero-fig {
  grid-column: 9 / span 4;
  align-self: end;
  margin: 0;
  min-width: 0;
}

.hero-shot {
  padding: 10px;
  border: 1px solid var(--ink);
  border-radius: var(--r);
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.hero-img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 20px;
}

.hero-plate {
  width: 100%;
  aspect-ratio: 4 / 5;
  border: 1px solid var(--ink);
  border-radius: var(--r);
  background: repeating-linear-gradient(135deg, var(--ink) 0 2px, transparent 2px 12px);
}

/* 正文 + 右侧栏 */
.band {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 16px;
  align-items: start;
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(28px, 5vw, 64px) var(--pad) clamp(44px, 6vw, 88px);
}

.band-main {
  grid-column: 1 / span 8;
  min-width: 0;
}

.rail {
  grid-column: 10 / span 3;
  display: grid;
  gap: 16px;
  position: sticky;
  top: 136px;
  min-width: 0;
}

.rail-block {
  padding: 18px;
  border: 1px solid var(--ink);
  border-radius: var(--r);
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.rail-title {
  margin: 0 0 12px;
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.rail-title > span {
  display: inline-block;
  padding-bottom: 4px;
  border-bottom: 3px solid var(--ink);
}

.rail-list {
  display: grid;
  margin: 0;
}

.rail-list a {
  display: flex;
  align-items: center;
  min-height: 42px;
  padding: 4px 0;
  border-bottom: 1px solid var(--line);
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  transition: padding 0.2s ease;
}

.rail-list a:last-child {
  border-bottom: 0;
}

.rail-list a:hover {
  padding-left: 6px;
}

/* 正文排版 */
.band-main > article {
  margin: 0 0 20px;
  padding: clamp(20px, 3vw, 36px);
  border: 1px solid var(--ink);
  border-radius: var(--r);
  background: var(--glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  scroll-margin-top: 140px;
}

.band-main > article:last-child {
  margin-bottom: 0;
}

.band-main h2 {
  margin: 0 0 16px;
  max-width: 22ch;
  font-size: clamp(24px, 3.1vw, 38px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.035em;
}

.band-main h2 > span {
  display: inline-block;
}

.band-main h2 > span::before {
  content: "";
  display: block;
  width: 38px;
  height: 4px;
  margin-bottom: 14px;
  background: var(--ink);
}

.band-main h3 {
  margin: 28px 0 10px;
  font-size: clamp(19px, 2.1vw, 24px);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.band-main h3 > span {
  display: inline-block;
  border-bottom: 3px solid var(--ink);
}

.band-main p {
  margin: 0 0 16px;
  max-width: 66ch;
}

.band-main ul,
.band-main ol {
  margin: 0 0 18px;
  padding-left: 1.25em;
  max-width: 66ch;
}

.band-main li {
  margin: 0 0 10px;
}

.band-main a {
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.band-main img {
  max-width: 100%;
  height: auto;
  margin: 8px 0 18px;
  border: 1px solid var(--ink);
  border-radius: 20px;
}

.band-main figure {
  margin: 0 0 18px;
}

.band-main figure img {
  margin: 0;
}

.band-main blockquote {
  margin: 0 0 18px;
  padding: 12px 0 12px 18px;
  border-left: 4px solid var(--ink);
  font-weight: 600;
}

.band-main strong {
  font-weight: 800;
}

.band-main table {
  width: 100%;
  margin: 0 0 18px;
  border-collapse: collapse;
  font-size: 16px;
}

.band-main th,
.band-main td {
  padding: 10px 8px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.band-main hr {
  margin: 24px 0;
  border: 0;
  border-top: 1px solid rgba(0, 0, 0, 0.25);
}

/* 页脚：仅 p 与 small */
.base {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 16px;
  padding: clamp(28px, 5vw, 56px) var(--pad) 20px;
  background: var(--ink);
  color: var(--paper);
}

.base-brand {
  grid-column: 1 / span 5;
  margin: 0;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.035em;
}

.base-nav {
  grid-column: 7 / span 6;
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 6px 18px;
  margin: 0;
}

.base-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.4);
  color: var(--paper);
  font-size: 16px;
  text-decoration: none;
}

.base-nav a:hover {
  border-bottom-color: var(--paper);
}

.base-copy {
  grid-column: 1 / -1;
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.24);
  text-align: center;
  font-size: 16px;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.72);
}

/* 滚动揭示 */
.js-reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

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

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    align-items: start;
    min-height: 0;
    padding-top: 26px;
  }

  .hero-copy,
  .hero-fig {
    grid-column: 1 / -1;
  }

  .hero-copy h1 {
    max-width: none;
  }

  .hero-fig {
    margin-top: 4px;
  }

  .band {
    grid-template-columns: 1fr;
  }

  .band-main,
  .rail {
    grid-column: 1 / -1;
  }

  .rail {
    position: static;
    grid-template-columns: 1fr 1fr;
  }

  .band-main > article {
    scroll-margin-top: 150px;
  }

  .base {
    grid-template-columns: 1fr;
  }

  .base-brand,
  .base-nav {
    grid-column: 1 / -1;
  }

  .base-nav {
    justify-content: flex-start;
  }
}

@media (max-width: 560px) {
  .rail {
    grid-template-columns: 1fr;
  }

  .mast-nav a {
    padding: 0 10px;
  }
}

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

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

  .dock,
  .skip {
    transition: none;
  }
}

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