/* ==========================================================================
   36沙龙国主页 · /assets/site.css
   共享外壳：重置 / 变量 / 中文排版 / 页头 / 页脚 / 基础组件
   ========================================================================== */

/* ---------- 1. 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, ul, ol, dl, dd { margin: 0; }

ul, ol { padding: 0; }
ul[class], ol[class] { list-style: none; }

img, picture, svg, video { display: block; max-width: 100%; }

a { color: inherit; text-decoration: none; }

button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }

table { border-collapse: collapse; }

/* ---------- 2. 变量 ---------- */
:root {
  --ink: #0A1622;
  --ink-soft: #12263A;
  --rule: #1E3A55;
  --cyan: #35F0D0;
  --cyan-dim: #1FA98F;
  --amber: #FFA33C;
  --paper: #E6EDF3;
  --muted: #8FA1B3;
  --muted-deep: #5C7186;
  --cream: #F2EDE3;
  --shadow: #05101A;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;

  --fs-display: clamp(2.5rem, 6vw, 4.5rem);
  --fs-h2: clamp(1.75rem, 3.4vw, 3rem);
  --fs-h3: clamp(1.25rem, 2vw, 2rem);
  --fs-h4: clamp(1.05rem, 1.4vw, 1.375rem);
  --fs-body: clamp(1rem, 1.05vw, 1.125rem);
  --fs-note: 0.875rem;
  --fs-mono: 0.8125rem;

  --gutter: clamp(1.25rem, 4vw, 4rem);
  --maxw: 1280px;
  --header-h: 76px;
  --gap: clamp(1.25rem, 3vw, 2.5rem);
  --radius: 2px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  padding-top: var(--header-h);
  background-color: var(--ink);
  background-image:
    repeating-linear-gradient(90deg, transparent 0 23px, rgba(30, 58, 85, 0.22) 23px 24px);
  background-attachment: fixed;
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  font-weight: 400;
  line-height: 1.85;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: 0.04em;
  color: var(--paper);
  text-wrap: balance;
}

h1 { font-size: var(--fs-display); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }
h4 { font-size: var(--fs-h4); }

p { text-wrap: pretty; }

strong { font-weight: 700; color: var(--paper); }

::selection {
  background: var(--cyan);
  color: var(--ink);
}

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 1px;
}

/* ---------- 4. 页面骨架 ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.prose {
  max-width: 38em;
  line-height: 1.85;
  color: var(--paper);
}

.prose p + p { margin-top: 1.1em; }

.section {
  position: relative;
  padding-block: clamp(2.5rem, 6vw, 5.5rem);
}

.section + .section { border-top: 1px solid var(--rule); }

.grid {
  display: grid;
  gap: var(--gap);
}

.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }

.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

/* ---------- 5. 工具类 ---------- */
.mono {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
}

.text-cyan { color: var(--cyan); }
.text-amber { color: var(--amber); }

.annotation {
  font-size: var(--fs-note);
  line-height: 1.6;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.annotation--vertical {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  letter-spacing: 0.24em;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.eyebrow::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}

/* ---------- 6. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 300;
  padding: 0.7rem 1.1rem;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
  border-radius: var(--radius);
  transform: translateY(-200%);
  transition: transform 160ms var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible { transform: translateY(0); }

/* ---------- 7. 页头 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 200ms var(--ease), border-color 200ms var(--ease);
}

.site-header[data-scrolled="true"] {
  background: rgba(10, 22, 34, 0.95);
  border-bottom-color: var(--rule);
}

@supports (backdrop-filter: blur(2px)) {
  .site-header[data-scrolled="true"] {
    background: rgba(10, 22, 34, 0.86);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }
}

.header-inner {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 3vw, 2.5rem);
  width: 100%;
  max-width: var(--maxw);
  min-height: var(--header-h);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 0 0 auto;
  padding-block: 0.5rem;
}

.brand-mark {
  flex: 0 0 auto;
  width: 14px;
  height: 26px;
  background-image:
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan-dim), var(--cyan-dim)),
    linear-gradient(var(--cyan-dim), var(--cyan-dim));
  background-repeat: no-repeat;
  background-size: 3px 26px, 3px 20px, 3px 14px;
  background-position: 0 0, 5.5px 6px, 11px 12px;
}

.brand-text {
  display: grid;
  gap: 0.1rem;
}

.brand-word {
  font-size: clamp(1.1rem, 1.5vw, 1.35rem);
  font-weight: 800;
  letter-spacing: 0.14em;
  line-height: 1.25;
  color: var(--paper);
  transition: color 160ms var(--ease);
}

.brand:hover .brand-word { color: var(--cyan); }

.brand-descriptor {
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.4;
  letter-spacing: 0.14em;
  color: var(--muted);
  white-space: nowrap;
}

/* 主导航 */
.primary-nav {
  margin-left: auto;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(0.4rem, 1.6vw, 1.5rem);
  counter-reset: nav;
}

.nav-item { counter-increment: nav; }

.nav-link {
  position: relative;
  display: inline-block;
  padding: 0.55rem 0.3rem;
  font-size: 0.9375rem;
  letter-spacing: 0.06em;
  color: var(--muted);
  transition: color 160ms var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.15rem;
  height: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 160ms var(--ease);
}

.nav-link:hover,
.nav-link:focus-visible { color: var(--paper); }

.nav-link:hover::after,
.nav-link:focus-visible::after { transform: scaleX(1); }

.nav-link[aria-current="page"] { color: var(--cyan); }
.nav-link[aria-current="page"]::after { transform: scaleX(1); }

.nav-panel-foot { display: none; }

/* 页头行动按钮 */
.header-cta {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 40px;
  padding: 0.5rem 1rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.1em;
  color: var(--paper);
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease), color 160ms var(--ease);
}

.header-cta::after {
  content: "→";
  color: var(--cyan);
  transition: transform 160ms var(--ease);
}

.header-cta:hover,
.header-cta:focus-visible {
  border-color: var(--cyan);
  background: rgba(53, 240, 208, 0.08);
  color: var(--cyan);
}

.header-cta:hover::after,
.header-cta:focus-visible::after { transform: translateX(3px); }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  position: fixed;
  right: 0;
  top: 50%;
  z-index: 3;
  width: 66px;
  padding: 1rem 0.25rem;
  transform: translateY(-50%);
  background: var(--ink-soft);
  border: 1px solid var(--rule);
  border-right: 0;
  border-radius: var(--radius) 0 0 var(--radius);
  color: var(--paper);
  text-align: center;
  box-shadow: -6px 0 18px rgba(5, 16, 26, 0.6);
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.nav-toggle:hover { border-color: var(--cyan-dim); }

.nav-toggle-glyph {
  display: grid;
  gap: 4px;
  width: 22px;
  margin: 0 auto 0.7rem;
}

.nav-toggle-glyph span {
  display: block;
  height: 2px;
  background: var(--cyan);
  transition: transform 200ms var(--ease), opacity 200ms var(--ease);
}

.nav-toggle-glyph span:nth-child(2) { width: 70%; }
.nav-toggle-glyph span:nth-child(3) { width: 45%; }

.nav-toggle-text {
  display: block;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.3em;
  color: var(--muted);
}

.nav-toggle[aria-expanded="true"] { border-color: var(--cyan); }

.nav-toggle[aria-expanded="true"] .nav-toggle-glyph span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-glyph span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-glyph span:nth-child(3) {
  width: 100%;
  transform: translateY(-6px) rotate(-45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-text { color: var(--cyan); }

/* 阅读进度 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  pointer-events: none;
}

.scroll-progress > span {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--cyan-dim), var(--cyan));
}

body[data-nav-open="true"] { overflow: hidden; }

/* ---------- 8. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(3rem, 7vw, 6rem);
  background: var(--shadow);
  color: var(--muted);
}

.footer-rule {
  height: 14px;
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  background-image: repeating-linear-gradient(90deg, var(--rule) 0 1px, transparent 1px 24px);
}

.footer-inner {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: clamp(2rem, 4vw, 3.5rem) var(--gutter) clamp(1.5rem, 3vw, 2rem);
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(200px, 1fr) minmax(0, 2.4fr);
  gap: clamp(1.5rem, 4vw, 3rem);
  padding-bottom: clamp(1.5rem, 3vw, 2.5rem);
  border-bottom: 1px solid var(--rule);
}

.footer-word {
  display: block;
  font-size: clamp(1.4rem, 2.4vw, 2rem);
  font-weight: 800;
  letter-spacing: 0.14em;
  line-height: 1.3;
  color: var(--paper);
}

.footer-desc {
  margin-top: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1rem, 2.5vw, 2rem);
}

.footer-col-title {
  margin-bottom: 0.9rem;
  padding-top: 0.7rem;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  font-weight: 400;
  letter-spacing: 0.14em;
  line-height: 1.4;
  color: var(--cyan);
}

.footer-links {
  display: grid;
  gap: 0.55rem;
  margin: 0;
}

.footer-links a {
  display: inline-block;
  font-size: 0.9375rem;
  letter-spacing: 0.02em;
  color: var(--muted);
  transition: color 160ms var(--ease), transform 160ms var(--ease);
}

.footer-links a:hover,
.footer-links a:focus-visible {
  color: var(--paper);
  transform: translateX(3px);
}

.footer-contact {
  max-width: 64ch;
  margin-top: clamp(1.25rem, 2.5vw, 2rem);
  font-size: 0.9375rem;
  line-height: 1.95;
  color: var(--muted);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem 1.5rem;
  margin-top: clamp(1.25rem, 2.5vw, 2rem);
  padding-top: 1.25rem;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--muted-deep);
}

/* ---------- 9. 通用组件 ---------- */
.panel {
  background: var(--ink-soft);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: clamp(1.25rem, 2.5vw, 2rem);
}

.panel--stack {
  box-shadow:
    6px 6px 0 0 rgba(5, 16, 26, 0.7),
    6px 6px 0 1px var(--rule);
}

.plate {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  height: 32px;
  padding: 0 0.75rem;
  background: var(--cream);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
  line-height: 1;
  border-radius: var(--radius);
  box-shadow: 3px 3px 0 rgba(5, 16, 26, 0.75);
  white-space: nowrap;
}

.plate--amber {
  background: var(--amber);
  color: var(--ink);
}

.beat-rail {
  position: relative;
  padding-left: 28px;
}

.beat-rail::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 1px;
  background: var(--rule);
}

.beat-rail::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 9px;
  background-image: repeating-linear-gradient(180deg, var(--rule) 0 1px, transparent 1px 24px);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  min-height: 44px;
  padding: 0.7rem 1.35rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.1em;
  color: var(--paper);
  background: transparent;
  transition: background-color 160ms var(--ease), border-color 160ms var(--ease), color 160ms var(--ease);
}

.btn--primary {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

.btn--primary:hover,
.btn--primary:focus-visible {
  background: transparent;
  color: var(--cyan);
}

.btn--ghost:hover,
.btn--ghost:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
}

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

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

.breadcrumb {
  padding-block: 1rem;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
  color: var(--muted);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumb li + li::before {
  content: "/";
  color: var(--rule);
}

.breadcrumb a {
  color: var(--muted);
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.breadcrumb a:hover,
.breadcrumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* 图片容器基础规则 */
.figure-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--ink-soft);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
}

.figure-frame > img,
.figure-frame > picture,
.figure-frame > svg,
.figure-frame > .figure-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.figure-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, transparent 0 23px, rgba(53, 240, 208, 0.1) 23px 24px),
    repeating-linear-gradient(180deg, transparent 0 23px, rgba(53, 240, 208, 0.06) 23px 24px);
  mix-blend-mode: screen;
}

.figure-frame--wide { aspect-ratio: 21 / 9; }
.figure-frame--tall { aspect-ratio: 4 / 5; }
.figure-frame--square { aspect-ratio: 1 / 1; }

.figure-caption {
  margin-top: 0.75rem;
  font-size: var(--fs-note);
  line-height: 1.6;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 10. 响应式：平板 ---------- */
@media (max-width: 1080px) {
  .brand-descriptor { display: none; }
  .nav-link { font-size: 0.875rem; }
  .header-cta { padding: 0.45rem 0.8rem; }
}

@media (max-width: 900px) {
  .grid--12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .col-4, .col-5, .col-7, .col-8 { grid-column: span 6; }

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

/* ---------- 11. 响应式：移动导航 ---------- */
@media (max-width: 860px) {
  :root { --header-h: 64px; }

  .header-cta { display: none; }

  .nav-toggle { display: block; }

  .primary-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 2;
    width: min(340px, 84vw);
    margin: 0;
    padding: calc(var(--header-h) + 1.5rem) 1.5rem 2rem;
    background: var(--ink-soft);
    border-left: 1px solid var(--rule);
    box-shadow: -18px 0 40px rgba(5, 16, 26, 0.7);
    overflow-y: auto;
    transform: translateX(102%);
    transition: transform 220ms var(--ease);
  }

  .primary-nav[data-open="true"] { transform: translateX(0); }

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

  .nav-link {
    display: flex;
    align-items: center;
    padding: 0.95rem 0;
    border-bottom: 1px solid var(--rule);
    font-size: 1.0625rem;
    letter-spacing: 0.08em;
  }

  .nav-link::after { display: none; }

  .nav-link::before {
    content: "0" counter(nav);
    margin-right: 0.85rem;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    color: var(--rule);
  }

  .nav-link[aria-current="page"]::before { color: var(--cyan); }

  .nav-panel-foot {
    display: grid;
    gap: 0.9rem;
    margin-top: 2rem;
  }

  .nav-panel-foot .btn { width: 100%; }

  .brand-word { font-size: 1.05rem; letter-spacing: 0.1em; }

  .footer-legal { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 560px) {
  .footer-cols { grid-template-columns: 1fr; }
  .footer-contact { font-size: 0.875rem; }
  .nav-toggle { width: 58px; }
  .plate { font-size: 0.75rem; }
}

/* ---------- 12. 减少动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .nav-link::after { transition: none; }
  .primary-nav { transition: none; }
}