@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;
  --hair: rgba(0, 0, 0, 0.16);
  --pad: clamp(1rem, 4vw, 3rem);
  --gut: clamp(1.5rem, 4vw, 3.5rem);
  --sans: 'Montserrat', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
  --serif: 'Cormorant', 'Songti SC', 'Times New Roman', serif;
}

*,
*::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: 400;
  line-height: 1.7;
  letter-spacing: 0.01em;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 220ms ease, background-color 220ms ease, color 220ms ease;
}

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

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

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

menu {
  margin: 0;
  padding: 0;
}

/* ---------- 页头 ---------- */

.masthead {
  position: sticky;
  top: 0;
  z-index: 60;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem var(--pad);
  background: var(--paper);
  border-bottom: 1px solid var(--ink);
}

.mast-side {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  min-width: 0;
}

.mast-right {
  justify-content: flex-end;
}

.brand {
  font-family: var(--serif);
  font-size: 1.45rem;
  font-weight: 600;
  letter-spacing: 0.32em;
  line-height: 1;
  padding: 0.55rem 0 0.55rem 0.32em;
  border-bottom: 0;
  white-space: nowrap;
}

.brand:hover {
  border-bottom: 0;
}

.drawer {
  position: relative;
}

.drawer summary {
  list-style: none;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.5rem 0.85rem;
  border: 1px solid var(--ink);
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  cursor: pointer;
  user-select: none;
  transition: background-color 220ms ease, color 220ms ease;
}

.drawer summary::-webkit-details-marker {
  display: none;
}

.drawer summary::marker {
  content: '';
}

.drawer[open] > summary {
  background: var(--ink);
  color: var(--paper);
}

.drawer menu {
  position: absolute;
  top: calc(100% + 0.55rem);
  left: 0;
  width: min(74vw, 19rem);
  background: var(--paper);
  border: 1px solid var(--ink);
  list-style: none;
  z-index: 70;
}

.drawer-right menu {
  left: auto;
  right: 0;
}

.drawer menu li + li {
  border-top: 1px solid var(--hair);
}

.drawer menu a {
  display: flex;
  align-items: center;
  min-height: 46px;
  padding: 0.6rem 1rem;
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  border-bottom: 0;
}

.drawer menu a:hover {
  background: var(--ink);
  color: var(--paper);
}

.contact {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.5rem 0.1rem;
  font-size: 0.8rem;
  letter-spacing: 0.18em;
}

/* ---------- 首屏 ---------- */

.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  align-items: center;
  padding: clamp(2.5rem, 7vw, 6rem) var(--pad);
  border-bottom: 1px solid var(--ink);
  overflow: hidden;
}

.hero-grid {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
  align-items: center;
}

.hero-copy h1 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.5rem, 7.6vw, 5.6rem);
  line-height: 1.14;
  letter-spacing: 0.01em;
  margin: 0;
  max-width: 22ch;
}

.hero-rule {
  display: block;
  width: 3.5rem;
  height: 1px;
  background: var(--ink);
  margin-bottom: clamp(1rem, 3vw, 2rem);
}

.hero-badge {
  position: absolute;
  top: clamp(1rem, 4vw, 2.25rem);
  right: var(--pad);
  z-index: 2;
  border: 1px solid var(--ink);
  background: var(--paper);
  padding: 0.42rem 0.85rem;
  font-size: 0.72rem;
  letter-spacing: 0.24em;
}

.hero-figure {
  margin: 0;
  border: 1px solid var(--ink);
  padding: 0;
}

.hero-figure img {
  width: 100%;
  height: auto;
}

/* ---------- 主体 ---------- */

main {
  padding: clamp(2.5rem, 6vw, 5rem) var(--pad);
}

.wrap {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 16rem;
  gap: var(--gut);
  align-items: start;
}

.prose {
  font-size: 1.0625rem;
  line-height: 1.78;
}

.prose > section {
  scroll-margin-top: 5.75rem;
}

.prose > section + section {
  margin-top: clamp(2.5rem, 5vw, 4rem);
  padding-top: clamp(2rem, 4vw, 3rem);
  border-top: 1px solid var(--ink);
}

.prose h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(1.6rem, 3.6vw, 2.4rem);
  line-height: 1.22;
  letter-spacing: 0.01em;
  margin: 0 0 0.85rem;
}

.prose h3 {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 1.12rem;
  letter-spacing: 0.02em;
  line-height: 1.5;
  margin: 2rem 0 0.6rem;
}

.prose hr {
  border: 0;
  border-top: 1px solid var(--ink);
  margin: 0 0 1.6rem;
}

.prose p {
  margin: 0 0 1.15rem;
}

.prose a {
  border-bottom: 1px solid var(--ink);
}

.prose ul,
.prose ol {
  margin: 0 0 1.3rem;
  padding-left: 1.35rem;
}

.prose li {
  margin-bottom: 0.5rem;
}

.prose blockquote {
  margin: 1.8rem 0;
  padding: 0.2rem 0 0.2rem 1.25rem;
  border-left: 3px solid var(--ink);
  font-family: var(--serif);
  font-size: 1.3rem;
  line-height: 1.5;
}

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

.prose strong {
  font-weight: 600;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.4rem;
  font-size: 0.95rem;
}

.prose th,
.prose td {
  border: 1px solid var(--ink);
  padding: 0.6rem 0.75rem;
  text-align: left;
}

/* ---------- 侧栏 ---------- */

.rail {
  position: sticky;
  top: 5.75rem;
  border: 1px solid var(--ink);
  padding: 1.1rem 1.1rem 0.6rem;
}

.rail h2 {
  font-family: var(--sans);
  font-weight: 500;
  font-size: 0.78rem;
  letter-spacing: 0.26em;
  margin: 0 0 0.55rem;
}

.rail hr {
  border: 0;
  border-top: 1px solid var(--ink);
  margin: 0 0 0.65rem;
}

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

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

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

.rail a {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  min-height: 42px;
  padding: 0.45rem 0;
  font-size: 0.92rem;
  line-height: 1.4;
  border-bottom: 0;
}

.rail a::before {
  counter-increment: rail;
  content: counter(rail, decimal-leading-zero);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: #000;
  opacity: 0.55;
  flex: none;
}

.rail a:hover::before {
  opacity: 1;
}

/* ---------- 页脚 ---------- */

.tail {
  border-top: 1px solid var(--ink);
  padding: clamp(2rem, 5vw, 3.5rem) var(--pad) 1.6rem;
}

.tail-brand {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(3rem, 13vw, 10rem);
  line-height: 0.92;
  letter-spacing: 0.02em;
  margin: 0 auto 1.6rem;
  max-width: 1200px;
}

.tail-row {
  max-width: 1200px;
  margin: 0 auto;
  border-top: 1px solid var(--ink);
  padding-top: 1.3rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2.5rem;
  justify-content: space-between;
  align-items: flex-start;
}

.tail address {
  font-style: normal;
  font-size: 0.82rem;
  letter-spacing: 0.22em;
  padding-top: 0.6rem;
}

.tail ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0 1.4rem;
}

.tail ul a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0.4rem 0;
  font-size: 0.82rem;
  letter-spacing: 0.06em;
}

.tail-copy {
  max-width: 1200px;
  margin: 2rem auto 0;
  text-align: center;
  font-size: 0.74rem;
  letter-spacing: 0.16em;
}

/* ---------- 断点 ---------- */

@media (min-width: 780px) {
  .hero-grid:has(.hero-figure) {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
  }
}

@media (max-width: 960px) {
  .wrap {
    grid-template-columns: minmax(0, 1fr);
  }

  .rail {
    position: static;
    order: 2;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 16px;
  }

  .brand {
    font-size: 1.1rem;
    letter-spacing: 0.2em;
    padding-left: 0.2em;
  }

  .masthead {
    padding: 0.6rem 1rem;
  }

  .drawer summary,
  .contact {
    font-size: 0.74rem;
    letter-spacing: 0.12em;
    padding: 0.45rem 0.6rem;
  }

  .contact {
    padding-left: 0.2rem;
    padding-right: 0.2rem;
  }

  .hero {
    min-height: 66vh;
    padding-top: 4rem;
  }

  .hero-badge {
    font-size: 0.66rem;
    letter-spacing: 0.18em;
  }

  .tail-row {
    flex-direction: column;
  }
}

/* ---------- 动效 ---------- */

.js .prose > section,
.js .rail {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 550ms ease, transform 550ms ease;
}

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

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

  *,
  *::before,
  *::after {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
  }
}

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