:root {
  --ink-deep: #0E1F18;
  --moss: #1C3A2C;
  --slate: #3A4440;
  --dew: #F3F6F0;
  --gold: #C9A96A;
  --petal: #E8B7C2;
  --apricot: #E7C9A9;
  --lichen: #A9B8AC;
  --ink: #101512;
  --brown: #8A6A3B;

  --font-display: "Songti SC", "Noto Serif SC", "Source Han Serif SC", SimSun, Georgia, serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, "Courier New", monospace;

  --shell: 1180px;
  --gutter: clamp(18px, 4vw, 48px);
  --header-h: 74px;
  --radius: 2px;

  --line: rgba(201, 169, 106, 0.28);
  --line-soft: rgba(169, 184, 172, 0.20);
  --hairline: rgba(16, 21, 18, 0.16);

  --dur: 200ms;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

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

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

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: 0.012em;
  color: var(--ink);
  background-color: var(--dew);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body.is-nav-open { overflow: hidden; }

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 300;
  line-height: 1.24;
  letter-spacing: 0.04em;
}

p { margin: 0 0 1.05em; }
p:last-child { margin-bottom: 0; }

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

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

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.24em;
  text-decoration-color: var(--gold);
}

button { font: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--brown);
  outline-offset: 3px;
  border-radius: 2px;
}

.on-dark :focus-visible,
.site-footer :focus-visible,
.site-header :focus-visible {
  outline-color: var(--petal);
}

#main-content { scroll-margin-top: calc(var(--header-h) + 18px); }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 0; left: 50%;
  z-index: 200;
  transform: translate(-50%, -130%);
  padding: 11px 22px;
  background: var(--dew);
  color: var(--ink-deep);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-decoration: none;
  border-radius: 0 0 3px 3px;
  transition: transform 180ms var(--ease);
}

.skip-link:focus { transform: translate(-50%, 0); }

/* ---------- 布局容器 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(56px, 8vw, 104px); }

.grid { display: grid; gap: clamp(20px, 3vw, 40px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr); align-items: start; }

/* ---------- 文字组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.8em;
  margin: 0 0 1em;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--brown);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: currentColor;
  opacity: 0.6;
}

.label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--lichen);
}

.lead {
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.95;
  color: var(--slate);
}

.rule {
  height: 1px;
  margin: 0;
  border: 0;
  background: var(--hairline);
}

.on-dark { color: var(--dew); }
.on-dark .lead { color: var(--lichen); }
.on-dark .eyebrow { color: var(--gold); }
.on-dark .label { color: var(--lichen); }
.on-dark .rule { background: var(--line-soft); }

.bg-deep { background-color: var(--ink-deep); color: var(--dew); }
.bg-moss { background-color: var(--moss); color: var(--dew); }
.bg-slate { background-color: var(--slate); color: var(--dew); }
.bg-dew { background-color: var(--dew); color: var(--ink); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6em;
  padding: 0.78em 1.35em;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 13.5px;
  letter-spacing: 0.1em;
  line-height: 1.4;
  text-decoration: none;
  background: transparent;
  cursor: pointer;
  transition: background-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.btn--outline {
  border-color: var(--gold);
  color: var(--gold);
}

.btn--outline:hover {
  background: var(--gold);
  color: var(--ink-deep);
}

.btn--solid {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--ink-deep);
}

.btn--solid:hover {
  background: var(--apricot);
  border-color: var(--apricot);
}

.btn--quiet {
  border-color: var(--hairline);
  color: inherit;
}

.btn--quiet:hover {
  border-color: var(--brown);
  color: var(--brown);
}

.on-dark .btn--quiet { border-color: var(--line-soft); }
.on-dark .btn--quiet:hover { border-color: var(--petal); color: var(--petal); }

.btn--sm { padding: 0.55em 1em; font-size: 12.5px; }

/* ---------- 面包屑 ---------- */
.crumbs {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--lichen);
}

.crumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7em;
  list-style: none;
  padding: 0;
  margin: 0;
}

.crumbs li + li::before {
  content: "/";
  margin-right: 0.7em;
  color: var(--gold);
  opacity: 0.7;
}

.crumbs a { text-decoration: none; }
.crumbs a:hover { color: inherit; text-decoration: underline; }

/* ---------- 图片与设备容器 ---------- */
.media {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background:
    radial-gradient(120% 100% at 20% 0%, rgba(201, 169, 106, 0.22), transparent 60%),
    linear-gradient(150deg, var(--moss), var(--slate));
}

.media > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.02);
}

.media--3x2 { aspect-ratio: 3 / 2; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }

.media__tag {
  position: absolute;
  left: 14px;
  bottom: 14px;
  padding: 4px 10px;
  background: rgba(14, 31, 24, 0.82);
  border: 1px solid var(--line);
  color: var(--apricot);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.device {
  width: 100%;
  max-width: 260px;
  aspect-ratio: 9 / 19.5;
  padding: 9px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--ink-deep);
  box-shadow:
    0 0 0 1px rgba(201, 169, 106, 0.08),
    0 34px 60px -38px rgba(0, 0, 0, 0.9);
}

.device__screen {
  width: 100%;
  height: 100%;
  overflow: hidden;
  border-radius: 21px;
  background: linear-gradient(165deg, var(--moss), var(--ink-deep));
}

/* ---------- 头部 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 90;
  color: var(--dew);
  background: linear-gradient(180deg, rgba(14, 31, 24, 0.94) 0%, rgba(14, 31, 24, 0.72) 62%, rgba(14, 31, 24, 0.38) 100%);
  -webkit-backdrop-filter: blur(10px) saturate(115%);
  backdrop-filter: blur(10px) saturate(115%);
  border-bottom: 1px solid transparent;
  transition: background-color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.site-header[data-scrolled="true"] {
  background: var(--moss);
  border-bottom-color: var(--line);
  box-shadow: 0 20px 36px -30px rgba(0, 0, 0, 0.9);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.2vw, 30px);
  min-height: var(--header-h);
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.site-header__progress {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: rgba(201, 169, 106, 0.14);
  overflow: hidden;
}

.site-header__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--gold), var(--petal));
  transition: width 120ms linear;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  color: var(--dew);
  text-decoration: none;
}

.brand__seal {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  flex: 0 0 36px;
  border: 1px solid var(--gold);
  border-radius: 50%;
  color: var(--gold);
  font-family: var(--font-display);
  font-size: 15px;
  line-height: 1;
  letter-spacing: 0;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.brand:hover .brand__seal { border-color: var(--petal); color: var(--petal); }

.brand__text { display: flex; flex-direction: column; line-height: 1.15; }

.brand__name {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 400;
  letter-spacing: 0.14em;
  color: var(--dew);
}

.brand__latin {
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--lichen);
}

.site-header__edition {
  margin: 0 0 0 clamp(8px, 1.6vw, 22px);
  padding-left: clamp(8px, 1.6vw, 22px);
  border-left: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: var(--lichen);
  white-space: nowrap;
}

/* 导航 */
.nav { margin-left: auto; }

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.5vw, 22px);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 0.42em;
  padding: 0.55em 0.1em;
  font-size: 14px;
  letter-spacing: 0.08em;
  color: rgba(243, 246, 240, 0.76);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.nav__index {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.08em;
  color: var(--gold);
  opacity: 0.6;
  transition: opacity var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0.1em;
  height: 1px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 220ms var(--ease), background-color var(--dur) var(--ease);
}

.nav__link:hover { color: var(--dew); }
.nav__link:hover::after { transform: scaleX(1); }
.nav__link:hover .nav__index { opacity: 1; }

.nav__link[aria-current="page"] { color: var(--dew); }
.nav__link[aria-current="page"] .nav__index { opacity: 1; color: var(--petal); }
.nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--petal);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: clamp(10px, 1.8vw, 24px);
}

/* 移动端索引按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 13px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: transparent;
  color: var(--dew);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-toggle__box {
  position: relative;
  display: block;
  width: 18px;
  height: 10px;
}

.nav-toggle__bar {
  position: absolute;
  left: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transition: transform var(--dur) var(--ease);
}

.nav-toggle__bar:nth-child(1) { top: 1px; }
.nav-toggle__bar:nth-child(2) { bottom: 1px; }

.site-header[data-open="true"] .nav-toggle {
  border-color: var(--petal);
  color: var(--petal);
}

.site-header[data-open="true"] .nav-toggle__bar:nth-child(1) { transform: translateY(4px) rotate(45deg); }
.site-header[data-open="true"] .nav-toggle__bar:nth-child(2) { transform: translateY(-4px) rotate(-45deg); }

/* ---------- 页脚 ---------- */
.site-footer {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border-top: 1px solid var(--line);
  color: var(--dew);
  font-size: 14.5px;
  background:
    radial-gradient(92% 74% at 84% -12%, rgba(201, 169, 106, 0.13), transparent 60%),
    radial-gradient(70% 62% at 6% 112%, rgba(232, 183, 194, 0.09), transparent 58%),
    var(--ink-deep);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -38%;
  right: -8%;
  width: min(560px, 62vw);
  aspect-ratio: 1;
  border: 1px solid rgba(201, 169, 106, 0.13);
  border-radius: 50%;
  pointer-events: none;
  z-index: -1;
}

.site-footer__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.75fr) minmax(0, 1.1fr);
  gap: clamp(26px, 3.6vw, 54px);
  padding-block: clamp(52px, 7vw, 90px) clamp(38px, 5vw, 62px);
}

.site-footer__grid > * + * {
  border-left: 1px solid var(--line-soft);
  padding-left: clamp(20px, 2.8vw, 42px);
}

.footer__brand {
  margin: 0 0 0.5em;
  font-family: var(--font-display);
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 300;
  letter-spacing: 0.16em;
  color: var(--dew);
}

.footer__tagline {
  margin: 0 0 1.5em;
  color: var(--lichen);
  font-size: 13.5px;
  line-height: 1.9;
}

.footer__stamp {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  opacity: 0.85;
}

.footer__nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(14px, 2vw, 30px);
}

.footer__title {
  margin: 0 0 1.05em;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 400;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--gold);
}

.footer__list { margin: 0; padding: 0; }
.footer__list li + li { margin-top: 0.1em; }

.footer__link {
  display: inline-block;
  padding: 0.22em 0;
  font-size: 14px;
  letter-spacing: 0.05em;
  color: rgba(243, 246, 240, 0.74);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer__link:hover {
  color: var(--dew);
  border-bottom-color: var(--gold);
}

.footer__link[aria-current="page"] {
  color: var(--petal);
  border-bottom-color: rgba(232, 183, 194, 0.55);
}

.footer__data {
  display: grid;
  gap: 15px;
  margin: 0;
}

.footer__row dt {
  margin-bottom: 3px;
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--lichen);
}

.footer__row dd { margin: 0; }

.copy {
  display: inline;
  padding: 0;
  border: 0;
  border-bottom: 1px dashed rgba(201, 169, 106, 0.42);
  background: none;
  color: rgba(243, 246, 240, 0.86);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.copy:hover {
  color: var(--dew);
  border-bottom-color: var(--petal);
}

.copy__text { overflow-wrap: anywhere; }

.copy__hint {
  margin-left: 0.55em;
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.16em;
  color: var(--gold);
  white-space: nowrap;
}

.copy[data-copied="true"] { border-bottom-color: var(--petal); }
.copy[data-copied="true"] .copy__hint { color: var(--petal); }

.footer__note {
  margin: 1.35em 0 0;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  color: rgba(169, 184, 172, 0.85);
}

.site-footer__base {
  border-top: 1px solid var(--line-soft);
  background: rgba(0, 0, 0, 0.2);
}

.site-footer__base-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 28px;
  padding-block: 18px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  color: var(--lichen);
}

.footer__icp,
.footer__copy { margin: 0; }

/* ---------- 手风琴 ---------- */
.accordion {
  border-top: 1px solid var(--hairline);
}

.accordion__item {
  border-bottom: 1px solid var(--hairline);
}

.on-dark .accordion,
.on-dark .accordion__item { border-color: var(--line-soft); }

.accordion__trigger {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  width: 100%;
  padding: 1.05em 0;
  border: 0;
  background: none;
  color: inherit;
  font-family: var(--font-display);
  font-size: clamp(16px, 1.5vw, 18px);
  font-weight: 400;
  letter-spacing: 0.05em;
  text-align: left;
  cursor: pointer;
  transition: color var(--dur) var(--ease);
}

.accordion__trigger:hover { color: var(--brown); }
.on-dark .accordion__trigger:hover { color: var(--petal); }

.accordion__icon {
  position: relative;
  flex: 0 0 14px;
  width: 14px;
  height: 14px;
  margin-top: 0.4em;
  transition: transform var(--dur) var(--ease);
}

.accordion__icon::before,
.accordion__icon::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 1px;
  background: var(--gold);
}

.accordion__icon::after { transform: rotate(90deg); }
.accordion__trigger[aria-expanded="true"] .accordion__icon { transform: rotate(45deg); }

.accordion__panel[data-open="true"] {
  animation: panel-in 200ms var(--ease) both;
}

.accordion__body {
  padding: 0 0 1.5em;
  color: var(--slate);
  font-size: 15.5px;
  line-height: 1.95;
}

.on-dark .accordion__body { color: var(--lichen); }

@keyframes panel-in {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1199px) {
  .site-header__edition { display: none; }
  .site-footer__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr);
  }
  .site-footer__grid > .footer__contact {
    grid-column: 1 / -1;
    border-left: 0;
    padding-left: 0;
    border-top: 1px solid var(--line-soft);
    padding-top: clamp(20px, 3vw, 32px);
  }
  .footer__data {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (max-width: 1023px) {
  :root { --header-h: 66px; }

  .header__cta { display: none; }
  .nav-toggle { display: inline-flex; }
  .site-header__actions { margin-left: auto; }

  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
    margin: 0;
    padding: 22px var(--gutter) 40px;
    background:
      radial-gradient(90% 60% at 88% 0%, rgba(201, 169, 106, 0.12), transparent 62%),
      linear-gradient(180deg, var(--moss), var(--ink-deep));
    border-top: 1px solid var(--line);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity var(--dur) var(--ease),
                transform var(--dur) var(--ease),
                visibility 0s linear var(--dur);
  }

  .site-header[data-open="true"] .nav {
    opacity: 1;
    visibility: visible;
    transform: none;
    transition-delay: 0s;
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav__item + .nav__item { border-top: 1px solid rgba(169, 184, 172, 0.16); }

  .nav__link {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 16px;
    padding: 15px 0;
    font-size: 18px;
    letter-spacing: 0.07em;
    color: var(--dew);
  }

  .nav__index { order: 2; font-size: 11px; opacity: 0.7; }
  .nav__link::after { display: none; }
  .nav__link[aria-current="page"] .nav__label { border-bottom: 1px solid var(--petal); }
}

@media (max-width: 899px) {
  .grid--2,
  .grid--3,
  .grid--split { grid-template-columns: minmax(0, 1fr); }

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

  .site-footer__grid > * + * {
    border-left: 0;
    padding-left: 0;
    border-top: 1px solid var(--line-soft);
    padding-top: clamp(20px, 4vw, 30px);
  }

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

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

  .site-footer__base-inner { justify-content: flex-start; }
}

@media (max-width: 520px) {
  .brand__latin { display: none; }
  .brand__name { font-size: 17px; letter-spacing: 0.1em; }
  .brand__seal { width: 32px; height: 32px; flex-basis: 32px; font-size: 13px; }
  .nav-toggle__text { display: none; }
  .footer__nav { grid-template-columns: minmax(0, 1fr); }
}

@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;
    scroll-behavior: auto !important;
  }

  .site-header__bar { transition: none; }
}