/* ============================================================
   控制方法论 · CONTROL METHODS
   深色科技感共享样式
   ============================================================ */

:root{
  --bg:#060910;
  --bg-2:#0b111a;
  --panel:rgba(255,255,255,.028);
  --panel-2:rgba(255,255,255,.05);
  --line:rgba(255,255,255,.085);
  --line-2:rgba(255,255,255,.14);
  --ink:#e9eef6;
  --ink-2:#8a96ab;
  --ink-3:#5d6878;
  --cyan:#46e0ff;
  --violet:#8f7dff;
  --green:#40d99a;
  --amber:#ffb454;
  --red:#ff6b7a;
  --c-p:#46e0ff;
  --c-i:#ffb454;
  --c-d:#40d99a;
  --mono:ui-monospace,SFMono-Regular,"JetBrains Mono",Menlo,Consolas,monospace;
  --radius:14px;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}

body{
  background:var(--bg);
  color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  line-height:1.75;
  font-size:16px;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}

/* 网格背景 + 顶部光晕 */
body::before{
  content:"";position:fixed;inset:0;z-index:-2;pointer-events:none;
  background-image:
    linear-gradient(rgba(255,255,255,.028) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.028) 1px,transparent 1px);
  background-size:48px 48px;
  -webkit-mask-image:radial-gradient(ellipse 90% 60% at 50% 0%,#000 20%,transparent 78%);
  mask-image:radial-gradient(ellipse 90% 60% at 50% 0%,#000 20%,transparent 78%);
}
body::after{
  content:"";position:fixed;top:-260px;left:50%;transform:translateX(-50%);
  width:900px;height:520px;z-index:-1;pointer-events:none;
  background:radial-gradient(ellipse at center,rgba(70,224,255,.14),rgba(143,125,255,.07) 45%,transparent 70%);
  filter:blur(30px);
}

.wrap{max-width:900px;margin:0 auto;padding:0 24px}

/* ---------- nav ---------- */
.nav{
  position:sticky;top:0;z-index:50;
  backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);
  background:rgba(6,9,16,.74);
  border-bottom:1px solid var(--line);
}
.nav-in{
  max-width:900px;margin:0 auto;padding:13px 24px;
  display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;
}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--ink)}
.brand .glyph{
  width:26px;height:26px;border-radius:7px;flex:none;
  background:linear-gradient(135deg,rgba(70,224,255,.22),rgba(143,125,255,.22));
  border:1px solid rgba(70,224,255,.4);
  display:grid;place-items:center;
}
.brand .glyph svg{display:block}
.brand span{font-family:var(--mono);font-size:12.5px;letter-spacing:.14em;color:var(--ink-2)}
.nav-links{display:flex;gap:4px;flex-wrap:wrap}
.nav-links a{
  text-decoration:none;color:var(--ink-2);font-size:14px;
  padding:6px 12px;border-radius:8px;transition:color .15s,background .15s;
  border:1px solid transparent;
}
.nav-links a:hover{color:var(--ink);background:var(--panel-2)}
.nav-links a.active{color:var(--cyan);background:rgba(70,224,255,.08);border-color:rgba(70,224,255,.25)}

/* ---------- hero ---------- */
.hero{padding:76px 0 52px}
.kicker{
  display:inline-block;font-family:var(--mono);font-size:12px;letter-spacing:.16em;
  color:var(--cyan);border:1px solid rgba(70,224,255,.32);border-radius:999px;
  padding:4px 13px;margin-bottom:22px;background:rgba(70,224,255,.06);
}
.kicker.violet{color:var(--violet);border-color:rgba(143,125,255,.35);background:rgba(143,125,255,.07)}
.kicker.amber{color:var(--amber);border-color:rgba(255,180,84,.35);background:rgba(255,180,84,.07)}
.kicker.green{color:var(--green);border-color:rgba(64,217,154,.35);background:rgba(64,217,154,.07)}

h1{
  font-size:clamp(32px,6.4vw,54px);line-height:1.15;letter-spacing:-.02em;
  font-weight:700;margin-bottom:16px;
}
h1 .grad{
  background:linear-gradient(115deg,var(--cyan),var(--violet));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
h1 .mono{font-family:var(--mono);color:var(--cyan)}
.lead{font-size:clamp(15.5px,2.4vw,18px);color:var(--ink-2);max-width:660px}

/* ---------- section ---------- */
section{padding:52px 0;border-bottom:1px solid var(--line)}
section:last-of-type{border-bottom:none}
.sec-head{margin-bottom:26px}
.sec-num{
  font-family:var(--mono);font-size:13px;color:var(--cyan);
  letter-spacing:.1em;display:block;margin-bottom:6px;
}
h2{font-size:clamp(22px,4vw,27px);letter-spacing:-.01em;font-weight:700;line-height:1.3}
.sub{color:var(--ink-2);font-size:15px;margin-top:6px}
h3{font-size:16.5px;margin:26px 0 10px;font-weight:650}
p{margin-bottom:14px}
strong{font-weight:650;color:var(--ink)}
em{font-style:normal;color:var(--cyan);font-family:var(--mono);font-size:.95em}
a.inline{color:var(--cyan);text-decoration:none;border-bottom:1px solid rgba(70,224,255,.35)}
a.inline:hover{border-bottom-color:var(--cyan)}

/* ---------- 公式 ---------- */
.formula{
  background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px 24px;text-align:center;margin:20px 0;overflow-x:auto;
  font-family:var(--mono);font-size:clamp(14px,3.4vw,18px);
  background-image:linear-gradient(135deg,rgba(70,224,255,.05),transparent 60%);
}
.formula .eq{color:var(--ink-3);margin:0 6px}
.formula .p{color:var(--c-p);font-weight:700}
.formula .i{color:var(--c-i);font-weight:700}
.formula .d{color:var(--c-d);font-weight:700}
.formula .cy{color:var(--cyan);font-weight:700}
.formula .vi{color:var(--violet);font-weight:700}
.formula .am{color:var(--amber);font-weight:700}

/* ---------- terms ---------- */
.terms{display:grid;grid-template-columns:repeat(auto-fit,minmax(215px,1fr));gap:12px;margin:18px 0 4px}
.term{
  border:1px solid var(--line);border-left:3px solid var(--cyan);
  border-radius:10px;padding:14px 16px;background:var(--panel);
}
.term.p{border-left-color:var(--c-p)}
.term.i{border-left-color:var(--c-i)}
.term.d{border-left-color:var(--c-d)}
.term .k{font-family:var(--mono);font-weight:700;font-size:14.5px;display:block;margin-bottom:5px}
.term.p .k{color:var(--c-p)}
.term.i .k{color:var(--c-i)}
.term.d .k{color:var(--c-d)}
.term .v{font-size:13.8px;color:var(--ink-2);line-height:1.65}

/* ---------- 图 ---------- */
.diagram{
  background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px 12px;margin:24px 0;overflow-x:auto;
  background-image:radial-gradient(circle at 50% 0%,rgba(70,224,255,.05),transparent 65%);
}
.diagram svg{display:block;margin:0 auto;max-width:100%;height:auto}
.cap{text-align:center;font-size:13px;color:var(--ink-3);margin-top:12px;font-family:var(--mono)}

/* ---------- 表格 ---------- */
.table-wrap{overflow-x:auto;margin:16px 0;border:1px solid var(--line);border-radius:12px}
table{width:100%;border-collapse:collapse;font-size:14.5px;min-width:520px}
th,td{padding:11px 15px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
th{background:var(--panel-2);font-weight:650;white-space:nowrap;font-size:14px}
tbody tr:last-child td{border-bottom:none}
tbody tr:hover{background:var(--panel)}
td .cy{color:var(--cyan)}
td .am{color:var(--amber)}
td .gr{color:var(--green)}
td .vi{color:var(--violet)}

/* ---------- 优缺点 ---------- */
.cols{display:grid;grid-template-columns:1fr 1fr;gap:18px}
@media(max-width:700px){.cols{grid-template-columns:1fr}}
.pcard{border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:var(--panel)}
.pcard .hd{padding:12px 18px;font-weight:700;font-size:14.5px;border-bottom:1px solid var(--line);font-family:var(--mono);letter-spacing:.04em}
.pcard.good .hd{background:rgba(64,217,154,.09);color:var(--green)}
.pcard.bad .hd{background:rgba(255,180,84,.09);color:var(--amber)}
.pcard ul{list-style:none;padding:15px 18px}
.pcard li{position:relative;padding-left:21px;margin-bottom:12px;font-size:14.3px;line-height:1.68;color:var(--ink-2)}
.pcard li:last-child{margin-bottom:0}
.pcard li::before{content:"";position:absolute;left:0;top:9px;width:7px;height:7px;border-radius:2px}
.pcard.good li::before{background:var(--green)}
.pcard.bad li::before{background:var(--amber)}
.pcard li b{color:var(--ink);font-weight:650}

/* ---------- 场景卡片 ---------- */
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(235px,1fr));gap:13px}
.sc{
  border:1px solid var(--line);border-radius:var(--radius);padding:17px 19px;
  background:var(--panel);transition:border-color .18s,transform .18s,background .18s;
}
.sc:hover{border-color:rgba(70,224,255,.45);transform:translateY(-3px);background:var(--panel-2)}
.sc .t{font-weight:650;margin-bottom:6px;font-size:15px;display:flex;align-items:center;gap:7px}
.sc .t .ic{font-size:16px}
.sc .d{font-size:13.8px;color:var(--ink-2);line-height:1.66}
.tag{
  display:inline-block;margin-top:10px;font-size:11.5px;font-family:var(--mono);
  background:rgba(70,224,255,.09);color:var(--cyan);
  padding:2px 9px;border-radius:6px;border:1px solid rgba(70,224,255,.2);
}
.tag.am{background:rgba(255,180,84,.09);color:var(--amber);border-color:rgba(255,180,84,.22)}
.tag.vi{background:rgba(143,125,255,.09);color:var(--violet);border-color:rgba(143,125,255,.22)}

/* ---------- 首页方法卡片 ---------- */
.mgrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(255px,1fr));gap:16px}
.mcard{
  display:flex;flex-direction:column;
  border:1px solid var(--line);border-radius:var(--radius);
  padding:22px 22px 18px;background:var(--panel);
  text-decoration:none;color:inherit;position:relative;overflow:hidden;
  transition:border-color .2s,transform .2s,box-shadow .2s;
}
.mcard::before{
  content:"";position:absolute;top:0;left:0;right:0;height:1px;
  background:linear-gradient(90deg,transparent,var(--accent,var(--cyan)),transparent);
  opacity:.5;
}
.mcard:hover{transform:translateY(-4px);border-color:rgba(70,224,255,.4);box-shadow:0 12px 40px -18px rgba(70,224,255,.5)}
.mcard .idx{font-family:var(--mono);font-size:12px;color:var(--ink-3);letter-spacing:.12em}
.mcard .nm{font-size:21px;font-weight:700;margin:8px 0 2px;letter-spacing:-.01em}
.mcard .en{font-family:var(--mono);font-size:12.5px;color:var(--ink-3);margin-bottom:12px}
.mcard .ds{font-size:14px;color:var(--ink-2);line-height:1.68;flex:1}
.mcard .meta{display:flex;flex-wrap:wrap;gap:6px;margin-top:14px}
.mcard .meta i{
  font-style:normal;font-size:11.5px;font-family:var(--mono);
  border:1px solid var(--line-2);border-radius:6px;padding:2px 8px;color:var(--ink-2);
}
.mcard .go{
  margin-top:14px;padding-top:13px;border-top:1px solid var(--line);
  font-size:13.5px;color:var(--cyan);font-family:var(--mono);
  display:flex;align-items:center;gap:6px;
}
.mcard:hover .go{gap:10px}
.mcard .go span{transition:margin .2s}

/* ---------- note ---------- */
.note{
  border-left:3px solid var(--cyan);background:var(--panel);
  padding:14px 18px;border-radius:0 10px 10px 0;
  font-size:14.3px;color:var(--ink-2);margin:20px 0;line-height:1.7;
}
.note b{color:var(--ink)}
.note.am{border-left-color:var(--amber)}
.note.vi{border-left-color:var(--violet)}

/* ---------- footer ---------- */
footer{padding:40px 0 56px;color:var(--ink-3);font-size:13px;text-align:center}
footer .mono{font-family:var(--mono);letter-spacing:.05em}
footer .sep{margin:0 8px;opacity:.5}

/* ---------- 通用 ---------- */
.mono{font-family:var(--mono)}
@media(max-width:560px){
  .nav-links a{padding:5px 9px;font-size:13px}
  .brand span{display:none}
  section{padding:42px 0}
  .hero{padding:56px 0 40px}
}

/* ============================================================
   浅色主题 [data-theme="light"]
   ============================================================ */
html{color-scheme:dark}
html[data-theme="light"]{
  color-scheme:light;
  --bg:#f5f7fa;
  --bg-2:#eef1f6;
  --panel:rgba(20,40,80,.028);
  --panel-2:rgba(20,40,80,.055);
  --line:rgba(20,40,80,.11);
  --line-2:rgba(20,40,80,.18);
  --ink:#182233;
  --ink-2:#52617a;
  --ink-3:#6e7d94;
  --cyan:#0a84c9;
  --violet:#5b4bd6;
  --green:#0b7f54;
  --amber:#b26f00;
  --red:#d42a44;
  --c-p:#0a84c9;
  --c-i:#b26f00;
  --c-d:#0b7f54;
}
[data-theme="light"] body::before{
  background-image:
    linear-gradient(rgba(20,50,100,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(20,50,100,.05) 1px,transparent 1px);
}
[data-theme="light"] body::after{
  background:radial-gradient(ellipse at center,rgba(10,132,201,.10),rgba(91,75,214,.05) 45%,transparent 70%);
}
[data-theme="light"] .nav{background:rgba(245,247,250,.82)}
[data-theme="light"] .kicker{border-color:rgba(10,132,201,.32);background:rgba(10,132,201,.05)}
[data-theme="light"] .kicker.violet{border-color:rgba(91,75,214,.32);background:rgba(91,75,214,.05)}
[data-theme="light"] .kicker.amber{border-color:rgba(178,111,0,.32);background:rgba(178,111,0,.05)}
[data-theme="light"] .kicker.green{border-color:rgba(11,127,84,.32);background:rgba(11,127,84,.05)}
[data-theme="light"] .nav-links a.active{background:rgba(10,132,201,.07);border-color:rgba(10,132,201,.25)}
[data-theme="light"] .formula,
[data-theme="light"] .diagram{background-image:linear-gradient(135deg,rgba(10,132,201,.045),transparent 60%)}
[data-theme="light"] .mcard:hover{border-color:rgba(10,132,201,.42);box-shadow:0 10px 32px -20px rgba(10,132,201,.45)}
[data-theme="light"] .sc:hover{border-color:rgba(10,132,201,.42)}
[data-theme="light"] .pcard.good .hd{background:rgba(11,127,84,.08)}
[data-theme="light"] .pcard.bad .hd{background:rgba(178,111,0,.08)}
[data-theme="light"] .tag{background:rgba(10,132,201,.07);border-color:rgba(10,132,201,.2)}
[data-theme="light"] .tag.am{background:rgba(178,111,0,.07);border-color:rgba(178,111,0,.22)}
[data-theme="light"] .tag.vi{background:rgba(91,75,214,.07);border-color:rgba(91,75,214,.22)}
[data-theme="light"] a.inline{border-bottom-color:rgba(10,132,201,.35)}

/* 浅色模式下 SVG 内嵌颜色重映射（CSS 覆盖呈现属性） */
[data-theme="light"] [fill="#5d6878"]{fill:#6e7d94}
[data-theme="light"] [stroke="#5d6878"]{stroke:#6e7d94}
[data-theme="light"] [fill="#46e0ff"]{fill:#0a84c9}
[data-theme="light"] [stroke="#46e0ff"]{stroke:#0a84c9}
[data-theme="light"] [fill="#8a96ab"]{fill:#52617a}
[data-theme="light"] [fill="#ffb454"]{fill:#b26f00}
[data-theme="light"] [stroke="#ffb454"]{stroke:#b26f00}
[data-theme="light"] [fill="#8f7dff"]{fill:#5b4bd6}
[data-theme="light"] [stroke="#8f7dff"]{stroke:#5b4bd6}
[data-theme="light"] [fill="#40d99a"]{fill:#0b7f54}
[data-theme="light"] [stroke="#40d99a"]{stroke:#0b7f54}
[data-theme="light"] [fill="#ff6b7a"]{fill:#d42a44}
[data-theme="light"] [stroke="#ff6b7a"]{stroke:#d42a44}
[data-theme="light"] [stroke="rgba(255,180,84,.55)"]{stroke:rgba(178,111,0,.55)}
[data-theme="light"] [fill="rgba(255,180,84,.55)"]{fill:rgba(178,111,0,.55)}
[data-theme="light"] [fill="rgba(255,180,84,.38)"]{fill:rgba(178,111,0,.38)}
[data-theme="light"] [fill="rgba(255,180,84,.25)"]{fill:rgba(178,111,0,.25)}
[data-theme="light"] [fill="rgba(255,180,84,.16)"]{fill:rgba(178,111,0,.16)}
[data-theme="light"] [fill="rgba(255,180,84,.08)"]{fill:rgba(178,111,0,.07)}
[data-theme="light"] [stroke="rgba(70,224,255,.5)"]{stroke:rgba(10,132,201,.55)}
[data-theme="light"] [fill="rgba(70,224,255,.07)"],[data-theme="light"] [fill="rgba(70,224,255,.08)"]{fill:rgba(10,132,201,.07)}
[data-theme="light"] [stroke="rgba(70,224,255,.4)"]{stroke:rgba(10,132,201,.45)}
[data-theme="light"] [stroke="rgba(64,217,154,.5)"]{stroke:rgba(11,127,84,.5)}
[data-theme="light"] [fill="rgba(64,217,154,.08)"]{fill:rgba(11,127,84,.07)}
[data-theme="light"] [fill="rgba(255,107,122,.09)"]{fill:rgba(212,42,68,.06)}
[data-theme="light"] [stroke="rgba(255,107,122,.6)"]{stroke:rgba(212,42,68,.6)}
[data-theme="light"] [fill="rgba(143,125,255,.07)"]{fill:rgba(91,75,214,.06)}
[data-theme="light"] [stroke="rgba(143,125,255,.4)"]{stroke:rgba(91,75,214,.45)}
[data-theme="light"] [stroke="rgba(143,125,255,.6)"]{stroke:rgba(91,75,214,.6)}

/* ---------- 主题切换按钮 ---------- */
.theme-btn{
  flex:none;width:34px;height:34px;border-radius:10px;
  background:var(--panel-2);border:1px solid var(--line-2);
  color:var(--ink-2);cursor:pointer;display:grid;place-items:center;
  transition:transform .15s,border-color .15s,color .15s;
}
.theme-btn:hover{color:var(--cyan);border-color:var(--cyan)}
.theme-btn:active{transform:scale(.9)}
.theme-btn svg{width:17px;height:17px;display:block}
.theme-btn .i-moon{display:none}
[data-theme="light"] .theme-btn .i-sun{display:none}
[data-theme="light"] .theme-btn .i-moon{display:block}