/* ============================================================
   流明 LUMEN · 基础与共用组件
   （页面私有的排版写在各自的 <style> 里）
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: var(--fs-16);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
::selection { background: var(--accent); color: #0a0a0b; }

:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 4px;
}

/* ---------- 背景：光晕 / 网格 / 颗粒 ---------- */

.bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  background: var(--bg);
  pointer-events: none;
}

.bg__blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(64px);
  opacity: .5;
  mix-blend-mode: screen;
  will-change: transform;
}

.bg__blob--1 {
  width: 78vw; height: 78vw; max-width: 1100px; max-height: 1100px;
  left: -18vw; top: -26vw;
  background: radial-gradient(circle at 50% 50%, var(--glow-1) 0%, rgba(31, 106, 112, .16) 38%, transparent 66%);
  animation: drift-a 46s var(--ease) infinite alternate;
}

.bg__blob--2 {
  width: 62vw; height: 62vw; max-width: 900px; max-height: 900px;
  right: -14vw; top: 6vh;
  background: radial-gradient(circle at 50% 50%, var(--glow-2) 0%, rgba(59, 53, 118, .14) 40%, transparent 68%);
  opacity: .42;
  animation: drift-b 58s var(--ease) infinite alternate;
}

.bg__blob--3 {
  width: 70vw; height: 70vw; max-width: 1000px; max-height: 1000px;
  left: 18vw; bottom: -34vw;
  background: radial-gradient(circle at 50% 50%, var(--glow-3) 0%, rgba(125, 77, 28, .13) 40%, transparent 68%);
  opacity: .4;
  animation: drift-c 64s var(--ease) infinite alternate;
}

.bg__blob--4 {
  width: 46vw; height: 46vw; max-width: 640px; max-height: 640px;
  right: 6vw; bottom: 8vh;
  background: radial-gradient(circle at 50% 50%, var(--glow-4) 0%, rgba(94, 36, 71, .12) 42%, transparent 70%);
  opacity: .34;
  animation: drift-b 52s var(--ease) infinite alternate-reverse;
}

/* 竖向栏线：像期刊的分栏 */
.bg__rails {
  position: absolute;
  inset: 0;
  max-width: var(--w-page);
  margin: 0 auto;
  padding: 0 40px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}
.bg__rails span {
  border-left: 1px solid rgba(233, 231, 225, .038);
}

/* 颗粒：把纯平的数字黑撑出一点质感 */
.bg__grain {
  position: absolute;
  inset: 0;
  opacity: .05;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='180' height='180' filter='url(%23n)'/%3E%3C/svg%3E");
}

.bg__vignette {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(120% 90% at 50% 0%, transparent 40%, rgba(4, 5, 6, .55) 100%),
    linear-gradient(180deg, rgba(4, 5, 6, .35) 0%, transparent 22%, transparent 78%, rgba(4, 5, 6, .5) 100%);
}

@keyframes drift-a {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to   { transform: translate3d(4vw, 3vh, 0) scale(1.08); }
}
@keyframes drift-b {
  from { transform: translate3d(0, 0, 0) scale(1.04); }
  to   { transform: translate3d(-3vw, 4vh, 0) scale(.96); }
}
@keyframes drift-c {
  from { transform: translate3d(0, 0, 0) scale(.98); }
  to   { transform: translate3d(-4vw, -3vh, 0) scale(1.06); }
}

/* ---------- 版心 ---------- */

.shell {
  width: 100%;
  max-width: var(--w-page);
  margin: 0 auto;
  padding: 0 40px;
  position: relative;
}

/* ---------- 刊头 ---------- */

.masthead {
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--faint);
}
.masthead__in {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  height: 38px;
}
.masthead__mid { color: var(--muted); letter-spacing: .22em; }
.masthead__dot {
  display: inline-block;
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  margin-right: 8px;
  vertical-align: 1px;
  box-shadow: 0 0 0 3px rgba(217, 166, 83, .12);
}

/* ---------- 顶栏 ---------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(7, 8, 10, .78);
  backdrop-filter: blur(16px) saturate(120%);
  -webkit-backdrop-filter: blur(16px) saturate(120%);
  border-bottom: 1px solid var(--line);
}
.topbar__in {
  display: flex;
  align-items: center;
  gap: var(--sp-7);
  height: 70px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--serif);
  font-size: var(--fs-18);
  letter-spacing: .04em;
  white-space: nowrap;
}
.brand__mark { color: var(--accent); flex: none; }
.brand__en {
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .3em;
  color: var(--faint);
  padding-left: 4px;
}

.nav {
  display: flex;
  align-items: center;
  gap: var(--sp-5);
  margin-left: auto;
  font-size: var(--fs-13);
  color: var(--text-2);
}
.nav a {
  position: relative;
  padding: 6px 2px;
  transition: color .2s var(--ease);
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .25s var(--ease);
}
.nav a:hover { color: var(--text); }
.nav a:hover::after,
.nav a[aria-current="page"]::after { transform: scaleX(1); }
.nav a[aria-current="page"] { color: var(--text); }

.topbar__issue {
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .12em;
  color: var(--faint);
  padding-left: var(--sp-5);
  border-left: 1px solid var(--line);
  white-space: nowrap;
}

/* ---------- 区块标题 ---------- */

.sec-head {
  display: flex;
  align-items: baseline;
  gap: var(--sp-3);
  padding-top: var(--sp-3);
  margin-bottom: var(--sp-6);
  border-top: 1px solid var(--line-2);
}
.sec-head__no {
  font-family: var(--mono);
  font-size: var(--fs-11);
  color: var(--accent);
  letter-spacing: .1em;
  padding-top: 10px;
}
.sec-head h2 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 500;
  font-size: var(--fs-28);
  letter-spacing: .02em;
  line-height: 1.3;
}
.sec-head__en {
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--faint);
  padding-top: 10px;
}
.sec-head__more {
  margin-left: auto;
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .1em;
  color: var(--muted);
  padding-top: 10px;
  transition: color .2s var(--ease);
}
.sec-head__more:hover { color: var(--accent); }

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  height: 46px;
  padding: 0 22px;
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: .12em;
  text-transform: uppercase;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease), transform .2s var(--ease);
}
.btn--solid { background: var(--accent); color: #100c05; border-color: var(--accent); }
.btn--solid:hover { background: #e9b967; border-color: #e9b967; transform: translateY(-1px); }
.btn--ghost { border-color: var(--line-2); color: var(--text-2); }
.btn--ghost:hover { border-color: var(--accent-dim); color: var(--text); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

/* ---------- 页脚 ---------- */

.footer {
  border-top: 1px solid var(--line-2);
  margin-top: var(--sp-9);
  padding: var(--sp-8) 0 var(--sp-6);
}
.footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: var(--sp-6);
}
.footer h3 {
  font-family: var(--mono);
  font-size: var(--fs-11);
  font-weight: 400;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--faint);
  margin: 0 0 var(--sp-3);
}
.footer__about {
  max-width: 40ch;
  color: var(--muted);
  font-size: var(--fs-13);
  line-height: 1.8;
  margin: 0;
}
.footer__links { display: grid; gap: 10px; font-size: var(--fs-13); color: var(--text-2); }
.footer__links a { display: inline-flex; align-items: center; gap: 8px; transition: color .2s var(--ease); }
.footer__links a:hover { color: var(--accent); }
.footer__links span:first-child {
  font-family: var(--mono);
  font-size: var(--fs-11);
  color: var(--faint);
  min-width: 44px;
}

.colophon {
  display: flex;
  justify-content: space-between;
  gap: var(--sp-4);
  flex-wrap: wrap;
  margin-top: var(--sp-8);
  padding-top: var(--sp-4);
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .1em;
  color: var(--faint);
}

/* ---------- 通用小件 ---------- */

.mono-label {
  font-family: var(--mono);
  font-size: var(--fs-11);
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--faint);
}

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

/* ---------- 响应式 ---------- */

@media (max-width: 980px) {
  .shell { padding: 0 24px; }
  .bg__rails { padding: 0 24px; grid-template-columns: repeat(2, 1fr); }
  .topbar__issue { display: none; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
  .footer__about { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .masthead__mid { display: none; }
  .topbar__in { height: 62px; gap: var(--sp-4); }
  .nav { gap: var(--sp-4); font-size: var(--fs-12); }
  .brand__en { display: none; }
  .sec-head { flex-wrap: wrap; }
  .sec-head__more { margin-left: 0; width: 100%; padding-top: 2px; }
  .footer__grid { grid-template-columns: 1fr; }
  .footer { margin-top: var(--sp-8); }
  .shell { padding: 0 20px; }
  .bg__rails { padding: 0 20px; }
  .colophon { font-size: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .bg__blob { animation: none !important; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}