/* ============================================================
   English Opera · 戏剧英文 — Design System
   Dark theater theme. CSS vars follow the colorlife convention.
   ============================================================ */

:root{
  --cl-bg:#0a0a12;
  --cl-bg-2:#101019;
  --cl-text:#f3eee4;
  --cl-text-dim:#a39d8e;
  --cl-border:rgba(245,197,66,.16);
  --cl-accent:#f5c542;          /* gold spotlight */
  --cl-accent-soft:rgba(245,197,66,.12);
  --cl-muted-bg:rgba(255,255,255,.04);
  --cl-logic:#5ad1c4;           /* teal = logic/structure */
  --cl-curtain:#7a1420;
  --cl-curtain-2:#b21f2e;
  --font-serif:"Microsoft YaHei","微软雅黑","SimHei","黑体","Heiti SC","黑体-简","PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC",sans-serif;
  --font-cn:"Microsoft YaHei","微软雅黑","SimHei","黑体","Heiti SC","黑体-简","PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC",sans-serif;
  --font-sans:"Microsoft YaHei","微软雅黑","SimHei","黑体","Heiti SC","黑体-简","PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC",sans-serif;
  --maxw:1120px;
  --r:16px;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  background:var(--cl-bg);
  color:var(--cl-text);
  font-family:var(--font-sans);
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
strong,b{color:var(--cl-text);font-weight:700}
code{font-family:"SFMono-Regular",Consolas,monospace;background:var(--cl-accent-soft);color:var(--cl-accent);padding:.05em .4em;border-radius:6px;font-size:.9em}

/* ===== Nav ===== */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:50;
  display:flex;align-items:center;justify-content:space-between;
  padding:14px clamp(16px,4vw,40px);
  background:rgba(10,10,18,.55);
  backdrop-filter:blur(14px);
  border-bottom:1px solid transparent;
  transition:border-color .4s,background .4s;
}
.nav.is-scrolled{border-color:var(--cl-border);background:rgba(10,10,18,.85)}
.nav__brand{font-family:var(--font-serif);font-weight:700;font-size:1.15rem;letter-spacing:.5px;display:flex;align-items:center;gap:8px}
.nav__mark{font-size:1.25rem}
.nav__links{display:flex;gap:clamp(10px,1.8vw,26px);list-style:none;font-size:.86rem;font-weight:400}
.nav__links a{color:var(--cl-text-dim);transition:color .25s;position:relative}
.nav__links a:hover{color:var(--cl-accent)}
.nav__links a::after{content:"";position:absolute;left:0;bottom:-4px;width:0;height:1px;background:var(--cl-accent);transition:width .25s}
.nav__links a:hover::after{width:100%}
/* parent dropdown menus */
.nav__item{position:relative}
.nav__parent-link{display:inline-flex;align-items:center;gap:4px;cursor:pointer}
.nav__parent--accent > .nav__parent-link{color:var(--cl-accent);font-weight:700}
.nav__parent--accent > .nav__parent-link:hover{color:#ffe08a}
.nav__caret{font-size:.62rem;opacity:.8}
.nav__dropdown{
  position:absolute;top:calc(100% + 10px);left:0;min-width:168px;
  list-style:none;display:none;flex-direction:column;gap:2px;padding:8px;
  background:rgba(12,12,20,.97);border:1px solid var(--cl-border);border-radius:12px;
  backdrop-filter:blur(14px);box-shadow:0 18px 44px rgba(0,0,0,.55);z-index:60;
}
/* hover 桥：填补父链接与下拉之间的 10px 间隙，避免鼠标移动时 hover 丢失（否则嵌套子菜单无法触发） */
.nav__dropdown::before{content:"";position:absolute;top:-12px;left:0;right:0;height:12px}
.nav__item:hover > .nav__dropdown{display:flex}
.nav__dropdown a{
  color:var(--cl-text-dim);padding:9px 13px;border-radius:8px;font-size:.84rem;white-space:nowrap;
  transition:color .2s,background .2s;
}
.nav__dropdown a:hover{color:var(--cl-accent);background:var(--cl-accent-soft)}
.nav__dropdown a::after{display:none}
/* nested submenu (词汇 ▸ COCA 词汇 ▸ COCA1000 …) */
.nav__sub{top:0;left:100%;margin-left:0;min-width:156px}
.nav__sub::before{content:"";position:absolute;top:0;left:-12px;width:12px;height:100%}
.nav__item:hover > .nav__sub{display:flex}
@media(max-width:820px){.nav__links{display:none}}

/* ===== Hero ===== */
.hero{position:relative;height:100vh;min-height:640px;display:flex;align-items:center;justify-content:center;overflow:hidden}
#stage-canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.hero__veil{position:absolute;inset:0;background:radial-gradient(120% 90% at 50% 30%,transparent 30%,rgba(10,10,18,.55) 70%,rgba(10,10,18,.92) 100%);pointer-events:none}
.hero__content{position:relative;z-index:2;text-align:center;padding:0 20px;max-width:880px;
  opacity:0;transform:translateY(24px);animation:heroIn 1.2s .3s cubic-bezier(.2,.7,.2,1) forwards}
@keyframes heroIn{to{opacity:1;transform:none}}
.hero__eyebrow{font-family:var(--font-cn);letter-spacing:6px;color:var(--cl-accent);font-size:.8rem;text-transform:uppercase;margin-bottom:18px}
.hero__title{font-family:var(--font-serif);font-weight:900;font-size:clamp(3rem,9vw,6.5rem);line-height:1;letter-spacing:2px;
  background:linear-gradient(180deg,#fff 0%,#f5c542 60%,#d99b2a 100%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
  text-shadow:0 0 60px rgba(245,197,66,.25)}
.hero__title-en{display:block;font-size:.32em;letter-spacing:10px;color:var(--cl-text-dim);-webkit-text-fill-color:var(--cl-text-dim);margin-top:10px;font-weight:700}
.hero__sub{font-family:var(--font-cn);font-size:clamp(1rem,2.4vw,1.35rem);color:var(--cl-text);margin:26px 0 30px;font-weight:400}
.hero__formula{display:flex;flex-wrap:wrap;gap:10px;align-items:center;justify-content:center;font-family:var(--font-cn);font-size:1.05rem}
.hero__formula .chip{background:var(--cl-muted-bg);border:1px solid var(--cl-border);padding:8px 16px;border-radius:999px;font-weight:500}
.hero__formula .chip--accent{border-color:var(--cl-accent);color:var(--cl-accent);box-shadow:0 0 22px rgba(245,197,66,.18)}
.hero__formula .op{color:var(--cl-accent);font-size:1.3rem;font-weight:700}
.hero__formula-eq{margin-left:8px;color:var(--cl-text-dim);font-size:.95rem}
.hero__axiom{margin-top:26px;font-family:var(--font-cn);color:var(--cl-text-dim);font-size:.95rem;font-style:italic}
.hero__scroll{display:inline-block;margin-top:42px;color:var(--cl-text-dim);font-size:.85rem;letter-spacing:2px;animation:bob 2s ease-in-out infinite}
@keyframes bob{0%,100%{transform:translateY(0)}50%{transform:translateY(8px)}}

/* ===== Sections ===== */
.section{max-width:var(--maxw);margin:0 auto;padding:clamp(70px,11vw,130px) clamp(16px,4vw,32px)}
.section--stage{
  max-width:none;
  background:
    radial-gradient(80% 60% at 50% 0%,rgba(245,197,66,.06),transparent 60%),
    linear-gradient(180deg,#0c0c16,#0a0a12);
  border-top:1px solid var(--cl-border);
  border-bottom:1px solid var(--cl-border);
}
.section--stage{max-width:none}
.section--stage > *{max-width:var(--maxw);margin-left:auto;margin-right:auto}
.section__head{text-align:center;margin-bottom:54px}
.section__no{display:inline-block;font-family:var(--font-cn);letter-spacing:4px;color:var(--cl-accent);font-size:.78rem;border:1px solid var(--cl-border);border-radius:999px;padding:5px 14px;margin-bottom:18px}
.section__title{font-family:var(--font-serif);font-weight:700;font-size:clamp(1.8rem,4.5vw,2.9rem);line-height:1.2}
.section__lead{color:var(--cl-text-dim);font-family:var(--font-cn);max-width:680px;margin:18px auto 0;font-size:1.02rem}

/* ===== Foundation pillars ===== */
.pillars{display:grid;grid-template-columns:1fr 1fr;gap:24px}
@media(max-width:780px){.pillars{grid-template-columns:1fr}}
.pillar{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:34px;position:relative;overflow:hidden}
.pillar::before{content:"";position:absolute;top:0;left:0;right:0;height:3px;background:linear-gradient(90deg,var(--cl-curtain-2),var(--cl-accent))}
.pillar__icon{font-size:2rem;margin-bottom:12px}
.pillar h3{font-family:var(--font-cn);font-size:1.3rem;font-weight:700;margin-bottom:4px}
.pillar__sub{color:var(--cl-accent);font-size:.82rem;letter-spacing:2px;margin-bottom:16px;text-transform:uppercase}
.pillar p{color:var(--cl-text);font-family:var(--font-cn);font-size:.98rem;margin-bottom:14px}
.pillar__list{list-style:none;margin:0 0 16px;display:grid;gap:8px}
.pillar__list li{padding-left:18px;position:relative;color:var(--cl-text-dim);font-family:var(--font-cn);font-size:.95rem}
.pillar__list li::before{content:"▸";position:absolute;left:0;color:var(--cl-accent)}
.pillar__note{font-size:.9rem;color:var(--cl-text-dim);border-left:2px solid var(--cl-accent);padding-left:12px;font-style:italic}

/* contrast */
.contrast{display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:20px;margin-top:30px}
@media(max-width:780px){.contrast{grid-template-columns:1fr}.contrast__vs{justify-self:center}}
.contrast__col{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:26px}
.contrast__col--cn{border-left:3px solid var(--cl-logic)}
.contrast__col--en{border-left:3px solid var(--cl-accent)}
.contrast__col h4{font-family:var(--font-cn);font-size:1.25rem;font-weight:700}
.contrast__meta{color:var(--cl-text-dim);font-size:.82rem;letter-spacing:1px;margin:4px 0 14px}
.contrast__col ul{list-style:none;display:grid;gap:10px}
.contrast__col li{font-family:var(--font-cn);font-size:.95rem;color:var(--cl-text);padding-left:16px;position:relative}
.contrast__col li::before{content:"·";position:absolute;left:2px;color:var(--cl-accent);font-weight:700}
.contrast__vs{font-family:var(--font-serif);font-weight:900;font-size:1.4rem;color:var(--cl-text-dim)}

.pull{font-family:var(--font-cn);font-size:clamp(1.1rem,2.6vw,1.5rem);text-align:center;max-width:760px;margin:46px auto 0;line-height:1.6;color:var(--cl-text)}
.pull--center{text-align:center;max-width:680px}
.pull strong{color:var(--cl-accent)}

/* ===== Architecture 533 ===== */
.arch{display:flex;flex-direction:column;align-items:center;gap:0}
.arch__tier{width:100%;text-align:center;padding:8px 0}
.arch__tag{display:inline-block;font-family:var(--font-cn);font-size:.8rem;letter-spacing:3px;color:var(--cl-text-dim);border:1px dashed var(--cl-border);border-radius:999px;padding:4px 14px;margin-bottom:18px}
.arch__nodes{display:flex;flex-wrap:wrap;gap:14px;justify-content:center}
.arch__node{min-width:96px;padding:16px 18px;border-radius:14px;border:1px solid var(--cl-border);background:var(--cl-muted-bg);display:flex;flex-direction:column;align-items:center;gap:4px;transition:transform .3s,box-shadow .3s,border-color .3s;cursor:default}
.arch__node:hover{transform:translateY(-6px)}
.arch__node b{font-family:var(--font-cn);font-size:1.15rem;font-weight:700}
.arch__node span{font-size:.72rem;letter-spacing:2px;color:var(--cl-text-dim);text-transform:uppercase}
.node--pat{border-color:rgba(90,209,196,.4)}
.node--pat:hover{box-shadow:0 10px 30px rgba(90,209,196,.18);border-color:var(--cl-logic)}
.node--clause{border-color:rgba(245,197,66,.4)}
.node--clause:hover{box-shadow:0 10px 30px rgba(245,197,66,.2);border-color:var(--cl-accent)}
.node--tvt{border-color:rgba(178,31,46,.5)}
.node--tvt:hover{box-shadow:0 10px 30px rgba(178,31,46,.3);border-color:var(--cl-curtain-2)}
.arch__label{font-family:var(--font-cn);color:var(--cl-text-dim);font-size:.92rem;margin-top:16px}
.arch__connector{width:2px;height:34px;background:linear-gradient(180deg,var(--cl-border),transparent)}
.arch__foot{font-family:var(--font-cn);color:var(--cl-text-dim);margin-top:26px;font-size:.95rem}
.arch__foot b{color:var(--cl-accent)}

/* ===== Cards (5 patterns) ===== */
.cards{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}
@media(max-width:980px){.cards{grid-template-columns:repeat(2,1fr)}}
@media(max-width:520px){.cards{grid-template-columns:1fr}}
.card{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:24px 20px;position:relative;transition:transform .35s,box-shadow .35s,border-color .35s;overflow:hidden}
.card:hover{transform:translateY(-8px);box-shadow:0 18px 40px rgba(0,0,0,.45)}
.card__code{font-family:var(--font-serif);font-weight:900;font-size:1.8rem;color:var(--cl-accent);letter-spacing:1px}
.card__name{font-family:var(--font-cn);font-size:1.15rem;font-weight:700;margin:8px 0 4px}
.card__drama{font-family:var(--font-cn);font-size:.82rem;color:var(--cl-logic);margin-bottom:14px}
.card__logic{font-family:var(--font-cn);font-size:.9rem;color:var(--cl-text);margin-bottom:12px;line-height:1.5}
.card__eg{font-family:var(--font-cn);font-size:.92rem;background:rgba(0,0,0,.3);border-radius:10px;padding:10px 12px;margin-bottom:12px;color:var(--cl-text)}
.card__eg u{text-decoration:none;border-bottom:2px solid var(--cl-accent);padding-bottom:1px}
.card__tip{font-family:var(--font-cn);font-size:.8rem;color:var(--cl-text-dim);border-top:1px dashed var(--cl-border);padding-top:10px}
.card--sv:hover{border-color:var(--cl-logic)}
.card--svc:hover{border-color:var(--cl-logic)}
.card--svo:hover{border-color:var(--cl-accent)}
.card--svoo:hover{border-color:var(--cl-accent)}
.card--svoc:hover{border-color:var(--cl-curtain-2)}

.diff{display:flex;flex-wrap:wrap;gap:14px;justify-content:center;align-items:center;margin-top:30px;background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:18px 24px;font-family:var(--font-cn);font-size:.9rem;color:var(--cl-text-dim)}
.diff__title{color:var(--cl-text);font-weight:700;font-size:1rem}
.diff b{color:var(--cl-accent)}

/* ===== Plugins (3 clauses) ===== */
.plugins{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
@media(max-width:860px){.plugins{grid-template-columns:1fr}}
.plugin{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:30px;position:relative}
.plugin__badge{position:absolute;top:18px;right:18px;font-family:var(--font-cn);font-size:.72rem;letter-spacing:2px;color:var(--cl-text-dim);border:1px solid var(--cl-border);border-radius:999px;padding:3px 10px}
.plugin h3{font-family:var(--font-cn);font-size:1.4rem;font-weight:700}
.plugin__type{color:var(--cl-accent);font-family:var(--font-cn);font-size:.92rem;margin:6px 0 16px}
.plugin p{font-family:var(--font-cn);font-size:.95rem;color:var(--cl-text);margin-bottom:14px}
.plugin__eg{background:rgba(0,0,0,.3);border-radius:10px;padding:12px 14px;font-size:1rem}
.plugin__test{font-size:.82rem;color:var(--cl-text-dim);border-left:2px solid var(--cl-logic);padding-left:10px;font-style:italic;margin-top:10px}
.hl-nom{background:rgba(245,197,66,.22);border-radius:4px;padding:0 4px;color:var(--cl-accent)}
.hl-rel{background:rgba(80,200,120,.2);border-radius:4px;padding:0 4px;color:#7ee6a0;font-weight:600}
.hl-adv{background:rgba(178,31,46,.28);border-radius:4px;padding:0 4px;color:#ff6f7d;font-weight:600}

/* ===== Effects TVT ===== */
.effects{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
@media(max-width:860px){.effects{grid-template-columns:1fr}}
.effect{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:32px;text-align:center;transition:transform .35s,box-shadow .35s}
.effect:hover{transform:translateY(-8px);box-shadow:0 18px 40px rgba(0,0,0,.4)}
.effect__icon{font-size:2.4rem;margin-bottom:10px}
.effect h3{font-family:var(--font-cn);font-size:1.4rem;font-weight:700}
.effect__metaphor{font-family:var(--font-cn);color:var(--cl-accent);font-size:.9rem;letter-spacing:1px;margin:6px 0 16px}
.effect p{font-family:var(--font-cn);font-size:.95rem;color:var(--cl-text);margin-bottom:12px}
.effect__rule{font-size:.85rem;color:var(--cl-text-dim);border-top:1px dashed var(--cl-border);padding-top:12px}

/* ===== Decompose ===== */
.decompose{max-width:900px;margin:0 auto}
.decompose__stage{background:linear-gradient(180deg,#0c0c16,#08080f);border:1px solid var(--cl-border);border-radius:var(--r);padding:34px 30px;min-height:140px;display:flex;align-items:center;box-shadow:inset 0 0 60px rgba(245,197,66,.05)}
.decompose__sentence{font-family:var(--font-cn);font-size:clamp(1.05rem,2.4vw,1.4rem);line-height:2.1;font-weight:400}
.decompose__sentence .tk{transition:all .5s;display:inline;padding:2px 3px;border-radius:5px}
.tk-adv,.tk-adv2{color:#ff6f7d}
.tk-sub{color:#f5c542;font-weight:700}
.tk-verb{color:#f5c542;font-weight:700;text-decoration:underline}
.tk-obj{color:#f5c542}
.tk-rel,.tk-rel2{color:#7ee6a0}

/* step states */
.decompose[data-step="0"] .tk-adv,.decompose[data-step="0"] .tk-adv2,
.decompose[data-step="0"] .tk-rel,.decompose[data-step="0"] .tk-rel2,
.decompose[data-step="0"] .tk-obj{opacity:.32;filter:blur(.4px)}
.decompose[data-step="1"] .tk-adv,.decompose[data-step="1"] .tk-adv2,
.decompose[data-step="1"] .tk-rel,.decompose[data-step="1"] .tk-rel2{opacity:.32;filter:blur(.4px)}
.decompose[data-step="2"] .tk-sub,.decompose[data-step="2"] .tk-verb,.decompose[data-step="2"] .tk-obj{opacity:1}
.decompose[data-step="2"] .tk-adv,.decompose[data-step="2"] .tk-adv2{color:#ff6f7d;opacity:1;filter:none;background:rgba(178,31,46,.22)}
.decompose[data-step="2"] .tk-rel,.decompose[data-step="2"] .tk-rel2{color:#7ee6a0;opacity:1;filter:none;background:rgba(80,200,120,.2)}
.decompose[data-step="3"] .tk{opacity:1!important;filter:none!important}
.decompose[data-step="3"] .tk-adv,.decompose[data-step="3"] .tk-adv2{background:rgba(178,31,46,.22)}
.decompose[data-step="3"] .tk-rel,.decompose[data-step="3"] .tk-rel2{background:rgba(80,200,120,.2)}
.decompose[data-step="3"] .tk-sub,.decompose[data-step="3"] .tk-verb,.decompose[data-step="3"] .tk-obj{background:rgba(245,197,66,.16)}

.decompose__steps{display:flex;gap:10px;margin:22px 0;flex-wrap:wrap}
.step{flex:1;min-width:120px;background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:12px;padding:14px;color:var(--cl-text-dim);font-family:var(--font-cn);font-size:.95rem;cursor:pointer;transition:all .3s;display:flex;align-items:center;gap:10px;justify-content:center}
.step__no{display:inline-flex;width:24px;height:24px;border-radius:50%;background:var(--cl-muted-bg);border:1px solid var(--cl-border);align-items:center;justify-content:center;font-weight:700;font-size:.85rem}
.step:hover{border-color:var(--cl-accent)}
.step.is-active{background:var(--cl-accent-soft);border-color:var(--cl-accent);color:var(--cl-text)}
.step.is-active .step__no{background:var(--cl-accent);color:#0a0a12;border-color:var(--cl-accent)}

.decompose__panel{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:28px 30px;min-height:150px}
.dp{display:none;font-family:var(--font-cn);animation:fadeIn .4s}
.dp.is-active{display:block}
.dp h4{font-family:var(--font-cn);color:var(--cl-accent);font-size:1.1rem;margin-bottom:12px}
.dp p{font-size:.98rem;color:var(--cl-text);margin-bottom:10px}
.dp ul{list-style:none;display:grid;gap:8px}
.dp li{font-size:.95rem;padding-left:16px;position:relative;color:var(--cl-text)}
.dp li::before{content:"▸";position:absolute;left:0;color:var(--cl-accent)}
@keyframes fadeIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* ===== Focus firewall ===== */
.firewall{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
@media(max-width:820px){.firewall{grid-template-columns:1fr}}
.fw{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:30px;position:relative;overflow:hidden}
.fw__no{font-family:var(--font-serif);font-weight:900;font-size:2.4rem;color:var(--cl-text-dim);opacity:.4;position:absolute;top:14px;right:20px}
.fw h3{font-family:var(--font-cn);font-size:1.3rem;font-weight:700;margin-bottom:12px;display:flex;align-items:center;gap:10px}
.fw p{font-family:var(--font-cn);font-size:.95rem;color:var(--cl-text-dim)}
.fw__key{background:var(--cl-accent);color:#0a0a12;font-size:.7rem;font-weight:700;padding:3px 9px;border-radius:999px;letter-spacing:1px}
.fw--s{border-color:var(--cl-accent);box-shadow:0 0 40px rgba(245,197,66,.14)}
.fw--s h3{color:var(--cl-accent)}

.stat{display:flex;align-items:center;gap:30px;margin-top:36px;background:linear-gradient(90deg,rgba(245,197,66,.08),transparent);border:1px solid var(--cl-border);border-radius:var(--r);padding:30px 34px;flex-wrap:wrap}
.stat__num{font-family:var(--font-serif);font-weight:900;font-size:clamp(3rem,8vw,5rem);line-height:1;background:linear-gradient(180deg,#fff,var(--cl-accent));-webkit-background-clip:text;background-clip:text;color:transparent;min-width:140px;text-align:center}
.stat__txt{font-family:var(--font-cn);font-size:1.02rem;color:var(--cl-text);flex:1;min-width:260px}
.stat__txt b{color:var(--cl-accent)}

/* ===== Deep-dive: 词汇 vs 句子 ===== */
.dd-sub{margin-top:56px;text-align:center}
.dd-sub__title{font-family:var(--font-cn);font-size:clamp(1.3rem,3vw,1.7rem);font-weight:700;color:var(--cl-text)}
.dd-sub__lead{font-family:var(--font-cn);color:var(--cl-text-dim);margin-top:10px;font-size:.98rem}

.deepdive{display:grid;grid-template-columns:1fr 1fr;gap:22px;margin-top:26px}
@media(max-width:820px){.deepdive{grid-template-columns:1fr}}

.dd-card{background:var(--cl-muted-bg);border:1px solid var(--cl-border);border-radius:var(--r);padding:30px;position:relative;overflow:hidden}
.dd-card::before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:linear-gradient(180deg,var(--cl-accent),rgba(245,197,66,.1))}
.dd-card--s::before{background:linear-gradient(180deg,var(--cl-logic),rgba(90,209,196,.1))}

.dd-card__head{display:flex;align-items:center;gap:14px;margin-bottom:18px}
.dd-card__icon{width:44px;height:44px;flex:0 0 44px;display:grid;place-items:center;font-family:var(--font-serif);font-weight:900;font-size:1.3rem;color:#0a0a12;background:linear-gradient(135deg,#ffe08a,var(--cl-accent));border-radius:12px;box-shadow:0 6px 18px rgba(245,197,66,.25)}
.dd-card__icon--s{color:#06110f;background:linear-gradient(135deg,#9af0e6,var(--cl-logic));box-shadow:0 6px 18px rgba(90,209,196,.22)}
.dd-card__title{font-family:var(--font-cn);font-size:1.45rem;font-weight:700;color:var(--cl-text);display:flex;align-items:baseline;gap:8px;flex-wrap:wrap}
.dd-card__eq{font-family:var(--font-cn);font-size:.92rem;font-weight:700;color:var(--cl-accent);letter-spacing:.5px}
.dd-card__eq--s{color:var(--cl-logic)}

.dd-read__label{font-family:var(--font-cn);font-size:.74rem;font-weight:700;letter-spacing:2px;color:var(--cl-text-dim);text-transform:none;margin-bottom:6px}
.dd-read{font-family:var(--font-cn);font-size:1.02rem;color:var(--cl-text);line-height:1.7;margin-bottom:20px}
.dd-read b{color:var(--cl-accent)}
.dd-card--s .dd-read b{color:var(--cl-logic)}

/* 词汇频率光谱 */
.spectrum{margin-bottom:20px}
.spectrum__bar{position:relative;height:34px;border-radius:8px;overflow:hidden;display:flex;align-items:center;justify-content:space-between;padding:0 12px;background:linear-gradient(90deg,var(--cl-accent) 0%,rgba(245,197,66,.5) 38%,var(--cl-curtain) 70%,var(--cl-curtain-2) 100%);font-family:var(--font-cn);font-size:.74rem;font-weight:700;color:#0a0a12}
.spectrum__lo{color:#fff}
.spectrum__mark{position:relative;height:0}
.spectrum__mark::before{content:"";position:absolute;left:38%;top:6px;width:2px;height:14px;background:var(--cl-text);transform:translateX(-1px)}
.spectrum__num{position:absolute;left:38%;top:18px;transform:translateX(-50%);font-family:var(--font-serif);font-weight:900;font-size:.8rem;color:var(--cl-text)}
.spectrum__cap{position:absolute;left:38%;top:34px;transform:translateX(-50%);font-family:var(--font-cn);font-size:.68rem;color:var(--cl-text-dim);white-space:nowrap}

/* 句子主干演绎 */
.deduce{margin-bottom:20px;background:rgba(90,209,196,.06);border:1px dashed rgba(90,209,196,.4);border-radius:12px;padding:20px;text-align:center}
.deduce__core{font-family:var(--font-serif);font-weight:700;font-size:1.15rem;color:var(--cl-logic);letter-spacing:.5px}
.deduce__arrow{display:block;margin:10px 0;font-family:var(--font-serif);font-weight:900;font-size:1.1rem;color:var(--cl-text)}
.deduce__note{font-family:var(--font-cn);font-size:.86rem;color:var(--cl-text-dim);line-height:1.6}

.dd-list{list-style:none;display:flex;flex-direction:column;gap:10px}
.dd-list li{font-family:var(--font-cn);font-size:.94rem;color:var(--cl-text-dim);line-height:1.6;padding-left:20px;position:relative}
.dd-list li::before{content:"";position:absolute;left:0;top:10px;width:7px;height:7px;border-radius:50%;background:var(--cl-accent)}
.dd-card--s .dd-list li::before{background:var(--cl-logic)}
.dd-list li b{color:var(--cl-text)}

/* ===== Footer ===== */
.footer{text-align:center;padding:80px 20px 60px;border-top:1px solid var(--cl-border);background:#08080f}
.footer__mantra{font-family:var(--font-serif);font-size:clamp(1.4rem,4vw,2.2rem);font-weight:700;background:linear-gradient(180deg,#fff,var(--cl-accent));-webkit-background-clip:text;background-clip:text;color:transparent}
.footer__sub{font-family:var(--font-cn);color:var(--cl-text-dim);margin-top:14px;font-size:.95rem}
.footer__src{font-family:var(--font-cn);color:var(--cl-text-dim);margin-top:18px;font-size:.82rem;opacity:.7}
.footer__src a{color:var(--cl-accent);text-decoration:underline}

/* ===== Reveal animation ===== */
.reveal{opacity:0;transform:translateY(30px);transition:opacity .8s cubic-bezier(.2,.7,.2,1),transform .8s cubic-bezier(.2,.7,.2,1)}
.reveal.is-in{opacity:1;transform:none}
@media(prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none}.hero__content{animation:none;opacity:1;transform:none}}