/* ===========================================================
   乐竞赛场 · 共享样式表 /assets/site.css
   头部 · 页脚 · 变量 · 排版 · 通用组件
   =========================================================== */

/* ---------- 1. 变量 ---------- */
:root {
  --c-void: #0B0F0C;
  --c-graphite: #171D18;
  --c-graphite-hi: #1F2620;
  --c-charcoal: #28302A;
  --c-lime: #C8FF3D;
  --c-orange: #FF7A1F;
  --c-blue: #3AD4FF;
  --c-cold: #F2F6EF;
  --c-mist: #9BA79D;
  --c-paper: #FFFFFF;

  --shell: 1240px;
  --gutter: clamp(1rem, 4vw, 3.5rem);
  --skew: 12deg;

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

  --ease: cubic-bezier(.2, .7, .2, 1);
  --dur: 180ms;
}

/* ---------- 2. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--c-void);
  color: var(--c-cold);
  font-family: var(--font-sans);
  font-size: clamp(15px, 1.05vw, 17px);
  font-weight: 400;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a { color: inherit; }

button { font: inherit; color: inherit; }

h1, h2, h3, h4, p, ul, ol, figure, blockquote { margin: 0; }

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

::selection { background: var(--c-lime); color: var(--c-void); }

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

/* ---------- 3. 中文排版基础 ---------- */
.lj-prose {
  max-width: 68ch;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--c-cold);
  overflow-wrap: break-word;
}

.lj-prose > * + * { margin-top: 1.15em; }

.lj-prose h2 {
  font-size: clamp(1.25rem, 2.2vw, 1.75rem);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.2;
  margin-top: 2.2em;
  padding-left: .7rem;
  border-left: 4px solid var(--c-lime);
}

.lj-prose h3 {
  font-size: clamp(1.08rem, 1.6vw, 1.3rem);
  font-weight: 800;
  letter-spacing: -.01em;
  margin-top: 1.8em;
}

.lj-prose p { color: #DCE4DB; }

.lj-prose strong { color: var(--c-lime); font-weight: 800; }

.lj-prose ul, .lj-prose ol { padding-left: 1.15rem; }

.lj-prose li { margin-top: .5em; }

.lj-prose ul > li { list-style: none; position: relative; }

.lj-prose ul > li::before {
  content: "";
  position: absolute;
  left: -1.1rem;
  top: .72em;
  width: 8px;
  height: 2px;
  background: var(--c-lime);
}

.lj-prose ol { list-style: decimal; }

.lj-prose ol > li::marker { color: var(--c-lime); font-family: var(--font-mono); }

.lj-prose a {
  color: var(--c-blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(58, 212, 255, .4);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.lj-prose a:hover { color: var(--c-lime); border-bottom-color: var(--c-lime); }

.lj-prose code, .lj-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---------- 4. 容器与网格 ---------- */
.lj-shell {
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.lj-main {
  display: block;
  padding-block: clamp(2rem, 5vw, 4rem) clamp(3rem, 7vw, 5.5rem);
}

.lj-section { padding-block: clamp(1.75rem, 4.5vw, 3.25rem); }

.lj-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(1rem, 2.5vw, 2rem);
  align-items: start;
}

.lj-col-wide { grid-column: 1 / span 7; }
.lj-col-note { grid-column: 9 / span 3; }
.lj-col-half { grid-column: 1 / span 6; }
.lj-col-right { grid-column: 6 / span 7; }
.lj-col-bleed { grid-column: 1 / -1; }

.lj-rule {
  border: 0;
  border-top: 1px solid var(--c-charcoal);
  margin-block: clamp(1.5rem, 4vw, 3rem);
}

/* ---------- 5. 标题与文本组件 ---------- */
.lj-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  font-weight: 600;
  letter-spacing: .16em;
  color: var(--c-lime);
}

.lj-eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  background: var(--c-lime);
  flex: 0 0 auto;
}

.lj-h1 {
  font-size: clamp(2rem, 5.6vw, 4.2rem);
  font-weight: 900;
  letter-spacing: -.03em;
  line-height: 1.02;
  margin: .35em 0 .35em;
  text-wrap: balance;
}

.lj-h2 {
  font-size: clamp(1.35rem, 2.8vw, 2rem);
  font-weight: 900;
  letter-spacing: -.022em;
  line-height: 1.15;
  text-wrap: balance;
}

.lj-lede {
  max-width: 52ch;
  font-size: clamp(1rem, 1.4vw, 1.14rem);
  color: var(--c-mist);
}

.lj-quote {
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 2vw, 1.45rem);
  line-height: 1.65;
  color: var(--c-cold);
  border-left: 3px solid var(--c-lime);
  padding-left: 1rem;
}

.lj-aside {
  background: var(--c-graphite);
  border: 1px solid var(--c-charcoal);
  padding: 1.1rem 1.2rem;
  font-size: .9rem;
  color: var(--c-mist);
}

.lj-aside__title {
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .1em;
  color: var(--c-orange);
  margin-bottom: .6rem;
}

/* ---------- 6. 面包屑 ---------- */
.lj-crumbs {
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--c-mist);
  margin-bottom: clamp(1.25rem, 3vw, 2rem);
}

.lj-crumbs__list { display: flex; flex-wrap: wrap; gap: .4rem; }

.lj-crumbs__item { display: inline-flex; align-items: center; gap: .4rem; }

.lj-crumbs__sep { color: var(--c-charcoal); }

.lj-crumbs__link {
  color: var(--c-mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.lj-crumbs__link:hover { color: var(--c-blue); border-bottom-color: var(--c-blue); }

.lj-crumbs__current { color: var(--c-cold); }

/* ---------- 7. 按钮 ---------- */
.lj-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .68rem 1.3rem;
  font-size: .92rem;
  font-weight: 800;
  letter-spacing: .01em;
  text-decoration: none;
  cursor: pointer;
  background: transparent;
  color: var(--c-cold);
  border: 1px solid var(--c-charcoal);
  clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.lj-btn:hover { transform: translateY(-1px); }

.lj-btn--lime {
  background: var(--c-lime);
  color: var(--c-void);
  border-color: var(--c-lime);
}

.lj-btn--lime:hover { background: var(--c-cold); border-color: var(--c-cold); }

.lj-btn--ghost {
  color: var(--c-lime);
  border-color: var(--c-lime);
}

.lj-btn--ghost:hover { background: var(--c-lime); color: var(--c-void); }

.lj-btn--blue {
  color: var(--c-blue);
  border-color: var(--c-blue);
}

.lj-btn--blue:hover { background: var(--c-blue); color: var(--c-void); }

/* ---------- 8. 跳转链接 ---------- */
.lj-skip {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  padding: .7rem 1.15rem;
  background: var(--c-lime);
  color: var(--c-void);
  font-weight: 800;
  font-size: .9rem;
  text-decoration: none;
  transform: translateY(-130%);
  transition: transform var(--dur) var(--ease);
}

.lj-skip:focus { transform: translateY(0); }

/* ---------- 9. 头部 ---------- */
.lj-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background: rgba(11, 15, 12, .94);
  border-bottom: 1px solid var(--c-charcoal);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.lj-header__inner {
  display: flex;
  align-items: center;
  gap: clamp(.5rem, 1.4vw, 1.25rem);
  min-height: 74px;
  padding-block: .55rem;
  position: relative;
}

.lj-brand {
  display: flex;
  align-items: center;
  gap: .65rem;
  flex: 0 0 auto;
  text-decoration: none;
  color: var(--c-cold);
}

.lj-brand__mark {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  background: var(--c-lime);
  color: var(--c-void);
  font-size: 1.2rem;
  font-weight: 900;
  letter-spacing: -.04em;
  clip-path: polygon(14% 0, 100% 0, 86% 100%, 0 100%);
  transition: background-color var(--dur) var(--ease);
}

.lj-brand:hover .lj-brand__mark { background: var(--c-blue); }

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

.lj-brand__name {
  font-size: 1.06rem;
  font-weight: 900;
  letter-spacing: -.02em;
}

.lj-brand__tag {
  font-size: .68rem;
  color: var(--c-mist);
  letter-spacing: .04em;
}

.lj-nav { margin-left: auto; }

.lj-nav__list {
  display: flex;
  align-items: center;
  gap: .25rem;
}

.lj-nav__link {
  display: block;
  padding: .52rem 1.05rem;
  font-size: .92rem;
  font-weight: 700;
  color: var(--c-mist);
  text-decoration: none;
  background: transparent;
  clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.lj-nav__link:hover {
  color: var(--c-cold);
  background: var(--c-graphite);
  transform: translateY(-1px);
}

.lj-nav__link[aria-current="page"] {
  background: var(--c-lime);
  color: var(--c-void);
}

.lj-nav__hint { display: none; }

.lj-cta {
  position: relative;
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
  margin-left: .6rem;
  padding: .55rem 1.15rem;
  font-size: .9rem;
  font-weight: 800;
  color: var(--c-lime);
  background: transparent;
  border: 1px solid var(--c-lime);
  text-decoration: none;
  transform: skewX(-12deg);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}

.lj-cta__label { display: block; transform: skewX(12deg); }

.lj-cta:hover { background: var(--c-lime); color: var(--c-void); border-color: var(--c-lime); }

.lj-burger {
  display: none;
  align-items: center;
  gap: .55rem;
  margin-left: auto;
  padding: .5rem .85rem;
  font-size: .85rem;
  font-weight: 800;
  color: var(--c-cold);
  background: var(--c-graphite);
  border: 1px solid var(--c-charcoal);
  cursor: pointer;
  clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.lj-burger:hover { border-color: var(--c-lime); color: var(--c-lime); }

.lj-burger__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 12px;
}

.lj-burger__bars::before,
.lj-burger__bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--c-lime);
  transition: transform var(--dur) var(--ease);
}

.lj-burger__bars::before { top: 0; }
.lj-burger__bars::after { bottom: 0; }

.lj-burger[aria-expanded="true"] .lj-burger__bars::before {
  transform: translateY(5px) rotate(45deg);
}

.lj-burger[aria-expanded="true"] .lj-burger__bars::after {
  transform: translateY(-5px) rotate(-45deg);
}

.lj-meter {
  height: 2px;
  background: var(--c-charcoal);
  overflow: hidden;
}

.lj-meter__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--c-lime), var(--c-blue));
  transition: width 90ms linear;
}

/* ---------- 10. 页脚 ---------- */
.lj-footer {
  position: relative;
  margin-top: clamp(3rem, 8vw, 6rem);
  background: var(--c-void);
  border-top: 1px solid var(--c-charcoal);
}

.lj-footer__slash {
  height: clamp(26px, 5vw, 54px);
  background: linear-gradient(90deg, rgba(200, 255, 61, .16), rgba(58, 212, 255, .07) 58%, transparent);
  clip-path: polygon(0 0, 100% 0, 100% 22%, 0 100%);
}

.lj-footer__inner { padding-block: clamp(2rem, 5vw, 3.5rem) 1.5rem; }

.lj-footer__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .6rem clamp(1rem, 4vw, 2.5rem);
  padding-bottom: clamp(1.25rem, 3vw, 2rem);
  border-bottom: 1px solid var(--c-charcoal);
}

.lj-footer__brand {
  font-size: clamp(1.9rem, 5.5vw, 3.4rem);
  font-weight: 900;
  letter-spacing: -.035em;
  line-height: 1;
  color: var(--c-cold);
}

.lj-footer__line {
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .04em;
  color: var(--c-mist);
}

.lj-footer__grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr 1.35fr;
  gap: clamp(1.5rem, 3.5vw, 3rem);
  padding-block: clamp(1.75rem, 4vw, 2.75rem);
}

.lj-footer__title {
  font-size: .76rem;
  font-weight: 800;
  letter-spacing: .14em;
  color: var(--c-mist);
  padding-left: .6rem;
  border-left: 3px solid var(--c-lime);
  margin-bottom: .9rem;
}

.lj-footer__list { display: grid; gap: .45rem; }

.lj-footer__item { line-height: 1.5; }

.lj-footer__link {
  position: relative;
  display: inline-block;
  font-size: .92rem;
  color: var(--c-cold);
  text-decoration: none;
  padding-bottom: 1px;
  background-image: linear-gradient(var(--c-lime), var(--c-lime));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0 1px;
  transition: background-size var(--dur) var(--ease), color var(--dur) var(--ease);
}

.lj-footer__link:hover {
  color: var(--c-lime);
  background-size: 100% 1px;
}

.lj-footer__block--lanes .lj-footer__link { font-weight: 700; }

.lj-footer__note {
  font-size: .88rem;
  color: var(--c-mist);
  margin-bottom: .9rem;
  max-width: 30ch;
}

.lj-footer__meta {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--c-cold);
  letter-spacing: .01em;
  margin-top: .55rem;
  overflow-wrap: anywhere;
}

.lj-footer__block--contact .lj-btn { margin-bottom: .35rem; }

.lj-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: .5rem 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px dashed var(--c-charcoal);
}

.lj-footer__legal {
  font-family: var(--font-mono);
  font-size: .76rem;
  color: var(--c-mist);
  letter-spacing: .02em;
}

/* ---------- 11. 通用内容模块 ---------- */
.lj-tag {
  display: inline-block;
  padding: .2rem .65rem;
  font-size: .72rem;
  font-weight: 800;
  letter-spacing: .06em;
  background: rgba(200, 255, 61, .14);
  color: var(--c-lime);
  clip-path: polygon(6px 0, 100% 0, calc(100% - 6px) 100%, 0 100%);
}

.lj-tag--orange { background: rgba(255, 122, 31, .16); color: var(--c-orange); }
.lj-tag--blue { background: rgba(58, 212, 255, .14); color: var(--c-blue); }

.lj-row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .4rem 1rem;
  padding: .85rem 1rem;
  background: var(--c-graphite);
  border-left: 3px solid var(--c-charcoal);
  color: inherit;
  text-decoration: none;
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.lj-row:hover {
  background: var(--c-graphite-hi);
  border-left-color: var(--c-lime);
  transform: translateX(2px);
}

.lj-row__title { font-weight: 800; letter-spacing: -.01em; }

.lj-row__meta {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--c-mist);
}

.lj-metric {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  padding-left: .9rem;
  border-left: 2px solid var(--c-charcoal);
}

.lj-metric__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.9rem, 5.4vw, 3.4rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.04em;
  color: var(--c-cold);
}

.lj-metric__label {
  font-size: .78rem;
  letter-spacing: .1em;
  color: var(--c-mist);
}

/* ---------- 12. 图片容器基础规则 ---------- */
.lj-figure { margin: 0; }

.lj-figure__media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--c-graphite) 0%, #101511 58%, rgba(200, 255, 61, .1) 100%);
  border: 1px solid var(--c-charcoal);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.lj-figure__media img,
.lj-figure__media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.lj-figure__caption {
  margin-top: .6rem;
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--c-mist);
}

.lj-figure--wide .lj-figure__media { aspect-ratio: 21 / 9; }
.lj-figure--tall .lj-figure__media { aspect-ratio: 3 / 4; }

/* ---------- 13. 横向轨道（时间轴 / 数据条） ---------- */
.lj-rail {
  display: flex;
  gap: clamp(.75rem, 2vw, 1.25rem);
  overflow-x: auto;
  padding-bottom: .85rem;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  scrollbar-color: var(--c-charcoal) transparent;
}

.lj-rail.is-dragging {
  cursor: grabbing;
  user-select: none;
  scroll-snap-type: none;
}

.lj-rail::-webkit-scrollbar { height: 6px; }
.lj-rail::-webkit-scrollbar-track { background: var(--c-graphite); }
.lj-rail::-webkit-scrollbar-thumb { background: var(--c-charcoal); }
.lj-rail::-webkit-scrollbar-thumb:hover { background: var(--c-lime); }

.lj-rail__item {
  flex: 0 0 clamp(230px, 62vw, 310px);
  scroll-snap-align: start;
}

/* ---------- 14. 显现动效 ---------- */
.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 320ms var(--ease), transform 400ms var(--ease);
}

.js-ready [data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1080px) {
  .lj-burger { display: inline-flex; }

  .lj-nav {
    position: absolute;
    left: calc(var(--gutter) * -1);
    right: calc(var(--gutter) * -1);
    top: 100%;
    margin: 0;
    padding: .85rem var(--gutter) 1.1rem;
    background: var(--c-graphite);
    border-bottom: 1px solid var(--c-charcoal);
    max-height: 0;
    overflow: hidden;
    visibility: hidden;
    opacity: 0;
    transform: translateY(-6px);
    transition: max-height 240ms var(--ease), opacity 160ms var(--ease),
      transform 200ms var(--ease), visibility 0s linear 240ms;
  }

  .lj-nav[data-open] {
    max-height: min(74vh, 540px);
    overflow-y: auto;
    visibility: visible;
    opacity: 1;
    transform: none;
    transition-delay: 0s;
  }

  .lj-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: .4rem;
  }

  .lj-nav__link {
    clip-path: none;
    padding: .72rem .95rem;
    font-size: 1rem;
    border-left: 3px solid var(--c-charcoal);
  }

  .lj-nav__link[aria-current="page"] { border-left-color: var(--c-void); }

  .lj-nav__hint {
    display: block;
    margin-top: 1rem;
    padding-top: .9rem;
    border-top: 1px dashed var(--c-charcoal);
    font-size: .82rem;
    line-height: 1.6;
    color: var(--c-mist);
  }

  .lj-cta { margin-left: 0; }
}

@media (max-width: 1024px) {
  .lj-col-wide,
  .lj-col-note,
  .lj-col-half,
  .lj-col-right { grid-column: 1 / -1; }

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

@media (max-width: 720px) {
  .lj-header__inner { min-height: 64px; }

  .lj-brand__tag { display: none; }

  .lj-brand__mark { width: 34px; height: 34px; font-size: 1.05rem; }

  .lj-cta { padding: .5rem .9rem; font-size: .82rem; }

  .lj-burger__text { display: none; }

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

  .lj-footer__bottom { justify-content: flex-start; }

  .lj-figure--wide .lj-figure__media { aspect-ratio: 16 / 9; }

  .lj-metric { padding-left: .7rem; }
}

@media (max-width: 420px) {
  .lj-brand__name { font-size: .98rem; }
  .lj-nav__link { font-size: .95rem; }
}

/* ---------- 16. 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .js-ready [data-reveal] { opacity: 1; transform: none; }

  .lj-meter__bar { transition: none; }
}