/* ============================================================
   铭星智学 · 门户站样式
   ============================================================ */

:root {
  --ink:        #070b1c;
  --ink-2:      #0b1026;
  --ink-3:      #111838;
  --primary:    #5b6cff;
  --primary-d:  #3f4fd8;
  --violet:     #8b5cf6;
  --cyan:       #22d3ee;
  --amber:      #fbbf24;

  --text:       #12182b;
  --text-2:     #475069;
  --muted:      #7b849c;
  --line:       #e6e9f2;
  --soft:       #f6f7fc;
  --white:      #ffffff;

  --radius:     18px;
  --radius-sm:  12px;
  --shadow-sm:  0 2px 10px rgba(18, 24, 43, .05);
  --shadow:     0 18px 48px rgba(18, 24, 43, .08);
  --shadow-lg:  0 30px 80px rgba(11, 16, 38, .35);

  --wrap:       1200px;
  --ease:       cubic-bezier(.22, .61, .36, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  color: var(--text);
  background: var(--ink);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5 { margin: 0; line-height: 1.3; font-weight: 700; letter-spacing: -.01em; }
p  { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }
a  { color: inherit; text-decoration: none; }

.wrap { width: min(100% - 48px, var(--wrap)); margin-inline: auto; }
.wrap-narrow { width: min(100% - 48px, 880px); }

/* ---------------- 通用按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: 8px; padding: 10px 20px; border-radius: 999px;
  font-size: 14px; font-weight: 600; white-space: nowrap;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease),
              background .25s var(--ease), color .25s var(--ease),
              border-color .25s var(--ease);
}
.btn-lg { padding: 14px 30px; font-size: 15px; }

.btn-primary {
  background: linear-gradient(120deg, var(--primary), var(--violet) 60%, #6d7bff);
  color: #fff;
  box-shadow: 0 10px 26px rgba(91, 108, 255, .32);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 36px rgba(91, 108, 255, .42); }

.btn-outline {
  border-color: rgba(255, 255, 255, .28);
  color: #fff; background: rgba(255, 255, 255, .04);
  backdrop-filter: blur(6px);
}
.btn-outline:hover { background: rgba(255, 255, 255, .12); transform: translateY(-2px); }

.btn-ghost { border-color: var(--line); color: var(--text); background: #fff; }
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }

/* ---------------- 导航 ---------------- */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  transition: background .3s var(--ease), box-shadow .3s var(--ease), border-color .3s;
  border-bottom: 1px solid transparent;
}
.nav-inner { display: flex; align-items: center; gap: 28px; height: 72px; }

.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark {
  display: grid; place-items: center; width: 38px; height: 38px;
  border-radius: 11px; background: rgba(255, 255, 255, .07);
  border: 1px solid rgba(255, 255, 255, .12);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-text b { font-size: 17px; color: #fff; letter-spacing: .02em; }
.brand-text i {
  font-style: normal; font-size: 10px; letter-spacing: .18em;
  color: rgba(255, 255, 255, .5); text-transform: uppercase;
}

.nav-links { display: flex; gap: 4px; margin-left: auto; }
.nav-links a {
  position: relative; padding: 8px 14px; border-radius: 8px;
  font-size: 14.5px; color: rgba(255, 255, 255, .78);
  transition: color .2s, background .2s;
}
.nav-links a:hover { color: #fff; background: rgba(255, 255, 255, .08); }

.nav-actions { display: flex; align-items: center; gap: 10px; }
.nav-actions .btn-ghost {
  background: rgba(255, 255, 255, .06); color: #fff;
  border-color: rgba(255, 255, 255, .2);
}
.nav-actions .btn-ghost:hover { background: rgba(255, 255, 255, .14); color: #fff; }

/* 滚动后 */
.nav.scrolled {
  background: rgba(255, 255, 255, .86);
  backdrop-filter: saturate(180%) blur(16px);
  border-bottom-color: var(--line);
  box-shadow: 0 6px 24px rgba(18, 24, 43, .06);
}
.nav.scrolled .brand-mark { background: #fff; border-color: var(--line); box-shadow: var(--shadow-sm); }
.nav.scrolled .brand-text b { color: var(--text); }
.nav.scrolled .brand-text i { color: var(--muted); }
.nav.scrolled .nav-links a { color: var(--text-2); }
.nav.scrolled .nav-links a:hover { color: var(--primary); background: rgba(91, 108, 255, .08); }
.nav.scrolled .nav-actions .btn-ghost {
  background: #fff; color: var(--text); border-color: var(--line);
}
.nav.scrolled .nav-actions .btn-ghost:hover { color: var(--primary); border-color: var(--primary); }

.nav-toggle { display: none; flex-direction: column; gap: 5px;
  width: 40px; height: 38px; align-items: center; justify-content: center;
  background: rgba(255, 255, 255, .06); border: 1px solid rgba(255, 255, 255, .18);
  border-radius: 10px; cursor: pointer; }
.nav-toggle span { display: block; width: 18px; height: 2px; background: #fff; border-radius: 2px;
  transition: transform .3s var(--ease), opacity .2s; }
.nav.scrolled .nav-toggle { border-color: var(--line); background: #fff; }
.nav.scrolled .nav-toggle span { background: var(--text); }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------------- Hero ---------------- */
.hero {
  position: relative; min-height: 92svh; padding: 128px 0 104px;
  background: radial-gradient(1200px 700px at 12% 8%, #1b2352 0%, transparent 60%),
              radial-gradient(1000px 600px at 88% 12%, #2a1a55 0%, transparent 58%),
              radial-gradient(900px 600px at 70% 90%, #0d3b52 0%, transparent 60%),
              linear-gradient(160deg, var(--ink) 0%, var(--ink-2) 45%, #0a0f24 100%);
  color: #fff; overflow: hidden;
}
.starfield { position: absolute; inset: 0; width: 100%; height: 100%; opacity: .75; }
.hero-glow {
  position: absolute; width: 620px; height: 620px; border-radius: 50%;
  right: -140px; top: -160px; filter: blur(120px); opacity: .38;
  background: linear-gradient(140deg, var(--primary), var(--violet) 50%, var(--cyan));
  animation: drift 22s ease-in-out infinite;
}
@keyframes drift {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50%      { transform: translate(-40px, 50px) scale(1.08); }
}
.hero-grid {
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.045) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.045) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: radial-gradient(circle at 50% 30%, #000 0%, transparent 72%);
  -webkit-mask-image: radial-gradient(circle at 50% 30%, #000 0%, transparent 72%);
}

.hero-inner {
  position: relative; z-index: 2;
  display: grid; grid-template-columns: 1.05fr .95fr; gap: 64px; align-items: center;
}

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px 6px 10px; margin-bottom: 26px;
  border: 1px solid rgba(255, 255, 255, .18); border-radius: 999px;
  background: rgba(255, 255, 255, .06);
  font-size: 13px; color: rgba(255, 255, 255, .86); letter-spacing: .01em;
}
.eyebrow .dot {
  width: 7px; height: 7px; border-radius: 50%; background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(34, 211, 238, .18);
  animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: .45; } }

.hero h1 {
  font-size: clamp(38px, 5.2vw, 62px); font-weight: 800; letter-spacing: -.02em;
  margin-bottom: 24px;
}
.grad {
  background: linear-gradient(100deg, #8fa0ff, #22d3ee 55%, #a78bfa);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lead {
  max-width: 560px; font-size: 17px; line-height: 1.95;
  color: rgba(255, 255, 255, .74);
}
.lead strong { color: #fff; font-weight: 600; }

.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 36px; }
.hero-note { margin-top: 20px; font-size: 13px; color: rgba(255, 255, 255, .45); }

/* 驾驶舱预览 */
.hero-visual { display: grid; gap: 16px; }
.panel {
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, .12);
  background: linear-gradient(160deg, rgba(255,255,255,.09), rgba(255,255,255,.03));
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  animation: floaty 8s ease-in-out infinite;
}
.panel:nth-child(2) { animation-delay: -2.6s; }
.panel:nth-child(3) { animation-delay: -5.2s; }
@keyframes floaty {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-8px); }
}

.panel-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 18px; border-bottom: 1px solid rgba(255, 255, 255, .09);
}
.panel-title { font-size: 14px; font-weight: 600; color: #fff; }
.chip {
  font-size: 11.5px; padding: 3px 10px; border-radius: 999px;
  background: rgba(255, 255, 255, .1); color: rgba(255, 255, 255, .8);
}
.chip-ok { background: rgba(34, 211, 238, .16); color: #7ee7f7; }

.panel-body { padding: 18px; }
.ring-row { display: flex; align-items: center; gap: 20px; }
.ring { position: relative; width: 108px; height: 108px; flex: none; }
.ring svg { width: 100%; height: 100%; }
.ring-label {
  position: absolute; inset: 0; display: grid; place-content: center; text-align: center;
}
.ring-label b { display: block; font-size: 22px; color: #fff; line-height: 1.1; }
.ring-label i { font-style: normal; font-size: 11px; color: rgba(255,255,255,.55); }

.ring-side { display: grid; gap: 8px; width: 100%; }
.mini {
  display: flex; justify-content: space-between; align-items: baseline;
  padding: 7px 12px; border-radius: 10px; background: rgba(255,255,255,.05);
  font-size: 12.5px; color: rgba(255,255,255,.65);
}
.mini b { font-size: 15px; color: #fff; }

.bars { display: grid; gap: 10px; margin-top: 16px; }
.bar { display: grid; grid-template-columns: 40px 1fr 40px; align-items: center; gap: 10px;
  font-size: 12.5px; color: rgba(255,255,255,.7); }
.bar b { text-align: right; color: #fff; font-size: 12px; }
.track { height: 6px; border-radius: 99px; background: rgba(255,255,255,.1); overflow: hidden; }
.track i {
  display: block; height: 100%; border-radius: 99px;
  background: linear-gradient(90deg, var(--primary), var(--cyan));
}

.todo { padding: 14px 18px 18px; display: grid; gap: 9px; }
.todo li { display: flex; align-items: center; gap: 10px; font-size: 13.5px; color: rgba(255,255,255,.78); }
.todo li i {
  width: 16px; height: 16px; border-radius: 5px; flex: none;
  border: 1.5px solid rgba(255,255,255,.28);
}
.todo li.done { color: rgba(255,255,255,.42); text-decoration: line-through; }
.todo li.done i {
  border-color: var(--cyan); background: var(--cyan);
  box-shadow: inset 0 0 0 2px rgba(11,16,38,.9);
}

.lib { display: flex; flex-wrap: wrap; gap: 8px; padding: 16px 18px; }
.lib-item {
  font-size: 12.5px; padding: 5px 12px; border-radius: 8px;
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.1);
  color: rgba(255,255,255,.75);
}

/* ---------------- 区块通用 ---------------- */
.section { padding: 100px 0; background: var(--ink-2); color: #fff; }
.section-soft { background: var(--ink-2); }

.sec-head { max-width: 720px; margin-bottom: 52px; }
.sec-head.center { margin-inline: auto; text-align: center; }
.kicker {
  display: inline-block; margin-bottom: 14px;
  font-size: 12.5px; font-weight: 700; letter-spacing: .16em;
  color: var(--cyan); text-transform: uppercase;
}
.sec-head h2 { font-size: clamp(26px, 3.2vw, 38px); margin-bottom: 16px; color: #fff; }
.sec-head p { color: rgba(255, 255, 255, .66); font-size: 16px; line-height: 1.9; }

.section-dark {
  background: radial-gradient(900px 500px at 15% 0%, #1a2350 0%, transparent 60%),
              linear-gradient(160deg, var(--ink-2), #0a0f24);
  color: #fff;
}
.sec-head-light h2 { color: #fff; }
.sec-head-light p { color: rgba(255,255,255,.66); }
.sec-head-light .kicker { color: var(--cyan); }

/* ---------------- 能力卡片 ---------------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

.card {
  position: relative; padding: 30px 28px 26px;
  border: 1px solid rgba(255, 255, 255, .12); border-radius: var(--radius);
  background: rgba(255, 255, 255, .05);
  backdrop-filter: blur(10px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, .25);
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), border-color .35s, background .35s;
  overflow: hidden; color: #fff;
}
.card::after {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--cyan));
  transform: scaleX(0); transform-origin: left;
  transition: transform .4s var(--ease);
}
.card:hover { transform: translateY(-6px); box-shadow: 0 18px 48px rgba(0, 0, 0, .35); border-color: rgba(255, 255, 255, .22); background: rgba(255, 255, 255, .08); }
.card:hover::after { transform: scaleX(1); }

.card-ico {
  display: grid; place-items: center; width: 42px; height: 42px; margin-bottom: 18px;
  border-radius: 12px; font-size: 17px; font-weight: 700; color: var(--cyan);
  background: rgba(255, 255, 255, .08); border: 1px solid rgba(255, 255, 255, .12);
}
.card h3 { font-size: 18.5px; margin-bottom: 10px; color: #fff; }
.card p  { font-size: 14.5px; color: rgba(255, 255, 255, .72); line-height: 1.85; }
.card-list { margin-top: 16px; display: grid; gap: 6px; }
.card-list li {
  position: relative; padding-left: 16px; font-size: 13.5px; color: var(--muted);
}
.card-list li::before {
  content: ""; position: absolute; left: 0; top: 10px;
  width: 5px; height: 5px; border-radius: 50%; background: var(--primary); opacity: .5;
}

/* ---------------- 学习闭环 ---------------- */
.loop {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 0;
  border: 1px solid rgba(255, 255, 255, .12); border-radius: var(--radius);
  background: rgba(255, 255, 255, .05); overflow: hidden; box-shadow: 0 10px 30px rgba(0, 0, 0, .2);
}
.loop-item {
  position: relative; padding: 30px 24px;
  border-right: 1px solid rgba(255, 255, 255, .12);
}
.loop-item:last-child { border-right: 0; }
.loop-item::after {
  content: "→"; position: absolute; right: -10px; top: 34px; z-index: 2;
  width: 20px; height: 20px; display: grid; place-items: center;
  font-size: 12px; color: var(--cyan); background: rgba(255, 255, 255, .08);
  border: 1px solid rgba(255, 255, 255, .12); border-radius: 50%;
}
.loop-item:last-child::after { content: "↺"; right: 12px; top: auto; bottom: 18px; color: var(--cyan); }
.loop-num {
  font-size: 26px; font-weight: 800; letter-spacing: -.02em; margin-bottom: 12px;
  background: linear-gradient(120deg, var(--primary), var(--cyan));
  -webkit-background-clip: text; background-clip: text; color: transparent;
  opacity: .85;
}
.loop-item h4 { font-size: 16px; margin-bottom: 8px; color: #fff; }
.loop-item p  { font-size: 13.5px; color: rgba(255, 255, 255, .68); line-height: 1.8; }

/* ---------------- 学段 Tabs ---------------- */
.tabs { border: 1px solid rgba(255, 255, 255, .12); border-radius: var(--radius);
  background: rgba(255, 255, 255, .05); box-shadow: 0 10px 30px rgba(0, 0, 0, .2);
  overflow: hidden; }
.tab-bar { display: flex; border-bottom: 1px solid rgba(255, 255, 255, .12); background: rgba(255, 255, 255, .04); }
.tab {
  flex: 1; padding: 18px 12px; border: 0; background: transparent; cursor: pointer;
  font-size: 15px; font-weight: 600; color: rgba(255, 255, 255, .7); font-family: inherit;
  border-bottom: 2px solid transparent;
  transition: color .25s, background .25s, border-color .25s;
}
.tab:hover { color: var(--cyan); }
.tab.active { color: #fff; background: rgba(255, 255, 255, .06); border-bottom-color: var(--cyan); }

.tab-panel { display: none; padding: 38px 36px; }
.tab-panel.active { display: block; animation: fade .35s var(--ease); }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.split { display: grid; grid-template-columns: 1.5fr 1fr; gap: 40px; align-items: start; }
.split-copy h3 { font-size: 22px; margin-bottom: 14px; color: #fff; }
.split-copy > p { color: rgba(255, 255, 255, .72); font-size: 15.5px; line-height: 1.95; margin-bottom: 18px; }
.split-copy strong { color: #fff; }

.ticks { display: grid; gap: 10px; }
.ticks li { position: relative; padding-left: 26px; font-size: 14.5px; color: rgba(255, 255, 255, .72); }
.ticks li::before {
  content: "✓"; position: absolute; left: 0; top: 0;
  color: var(--cyan); font-weight: 700;
}

.split-side {
  display: grid; gap: 10px; padding: 22px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(255, 255, 255, .12);
}
.kv { display: flex; justify-content: space-between; align-items: center; gap: 12px;
  padding-bottom: 10px; border-bottom: 1px dashed rgba(255, 255, 255, .15); font-size: 13.5px; }
.kv:last-child { border-bottom: 0; padding-bottom: 0; }
.kv span { color: rgba(255, 255, 255, .55); }
.kv b { color: #fff; font-weight: 600; }

/* ---------------- 科学方法 ---------------- */
.principle {
  padding: 28px 24px; border-radius: var(--radius);
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(255, 255, 255, .12); box-shadow: 0 10px 30px rgba(0, 0, 0, .2);
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), background .35s, border-color .35s;
}
.principle:hover { transform: translateY(-6px); box-shadow: 0 18px 48px rgba(0, 0, 0, .3); background: rgba(255, 255, 255, .08); border-color: rgba(255, 255, 255, .2); }
.p-ico {
  display: grid; place-items: center; width: 40px; height: 40px; margin-bottom: 16px;
  border-radius: 11px; font-size: 18px; color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--violet));
}
.principle h4 { font-size: 16.5px; margin-bottom: 8px; color: #fff; }
.principle p { font-size: 14px; color: rgba(255, 255, 255, .7); line-height: 1.85; }

.science-extra { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 22px; }
.se-card {
  padding: 26px 24px; border-radius: var(--radius);
  border: 1px dashed rgba(255, 255, 255, .2); background: rgba(255, 255, 255, .05);
}
.se-card h4 { font-size: 16px; margin-bottom: 10px; color: var(--cyan); }
.se-card p { font-size: 14px; color: rgba(255, 255, 255, .7); line-height: 1.9; }

/* ---------------- 高考专项 ---------------- */
.gk-top {
  display: flex; align-items: center; gap: 32px; flex-wrap: wrap;
  padding: 26px 30px; margin-bottom: 44px;
  border: 1px solid rgba(255,255,255,.12); border-radius: var(--radius);
  background: linear-gradient(120deg, rgba(91,108,255,.16), rgba(34,211,238,.08));
  backdrop-filter: blur(6px);
}
.countdown { display: flex; align-items: baseline; gap: 8px; }
.cd-label { font-size: 14px; color: rgba(255,255,255,.7); }
.countdown b {
  font-size: 46px; font-weight: 800; line-height: 1;
  background: linear-gradient(120deg, #a5b4ff, #22d3ee);
  -webkit-background-clip: text; background-clip: text; color: transparent;
  font-variant-numeric: tabular-nums;
}
.cd-unit { font-size: 16px; color: rgba(255,255,255,.6); }
.cd-date { margin-left: 8px; font-size: 12.5px; color: rgba(255,255,255,.45); }
.gk-top-note { flex: 1; min-width: 260px; font-size: 14px; color: rgba(255,255,255,.62); line-height: 1.9; }

.timeline { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; position: relative; }
.tl-item {
  position: relative; padding: 28px 24px; border-radius: var(--radius);
  border: 1px solid rgba(255,255,255,.12); background: rgba(255,255,255,.04);
  backdrop-filter: blur(6px);
  transition: transform .35s var(--ease), background .35s, border-color .35s;
}
.tl-item:hover { transform: translateY(-6px); background: rgba(255,255,255,.08); border-color: rgba(34,211,238,.4); }
.tl-dot {
  position: absolute; top: -6px; left: 24px; width: 12px; height: 12px; border-radius: 50%;
  background: var(--cyan); box-shadow: 0 0 0 4px rgba(34,211,238,.2);
}
.tl-tag {
  display: inline-block; margin-bottom: 12px; padding: 3px 10px; border-radius: 6px;
  font-size: 12px; font-weight: 600; color: #0b1026; background: var(--cyan);
}
.tl-item h4 { font-size: 17px; color: #fff; margin-bottom: 10px; }
.tl-item p { font-size: 13.5px; color: rgba(255,255,255,.6); line-height: 1.85; }

/* ---------------- 克制说明 ---------------- */
.promise { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.promise-col {
  padding: 34px 32px; border-radius: var(--radius);
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(255, 255, 255, .12); box-shadow: 0 10px 30px rgba(0, 0, 0, .2);
}
.promise-col h3 { font-size: 19px; margin-bottom: 18px; }
.promise-col h3.ok { color: var(--cyan); }
.promise-col h3.no { color: #f59e0b; }
.promise-col ul { display: grid; gap: 14px; }
.promise-col li { font-size: 14.5px; color: rgba(255, 255, 255, .72); line-height: 1.85; padding-left: 16px; position: relative; }
.promise-col li::before {
  content: ""; position: absolute; left: 0; top: 12px;
  width: 6px; height: 6px; border-radius: 50%; background: currentColor; opacity: .35;
}
.promise-col li b { color: #fff; font-weight: 600; }

/* ---------------- FAQ ---------------- */
.faq { border: 1px solid rgba(255, 255, 255, .12); border-radius: var(--radius);
  background: rgba(255, 255, 255, .05); box-shadow: 0 10px 30px rgba(0, 0, 0, .2);
  overflow: hidden; }
.faq-item { border-bottom: 1px solid rgba(255, 255, 255, .12); }
.faq-item:last-child { border-bottom: 0; }
.faq-q {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 20px 26px; border: 0; background: transparent; cursor: pointer;
  font-size: 15.5px; font-weight: 600; color: #fff; text-align: left;
  font-family: inherit; transition: background .25s, color .25s;
}
.faq-q:hover { background: rgba(255, 255, 255, .05); color: var(--cyan); }
.faq-arrow {
  position: relative; flex: none; width: 16px; height: 16px;
}
.faq-arrow::before, .faq-arrow::after {
  content: ""; position: absolute; background: var(--cyan); border-radius: 2px;
  transition: transform .3s var(--ease), opacity .3s;
}
.faq-arrow::before { top: 7px; left: 0; width: 16px; height: 2px; }
.faq-arrow::after  { left: 7px; top: 0; width: 2px; height: 16px; }
.faq-item.open .faq-arrow::after { transform: rotate(90deg); opacity: 0; }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .35s var(--ease); }
.faq-a p { padding: 0 26px 22px; font-size: 14.5px; color: rgba(255, 255, 255, .7); line-height: 1.95; }

/* ---------------- 页脚 ---------------- */
.footer { padding: 64px 0 28px; background: #070b1a; color: rgba(255,255,255,.6); }
.footer-inner { display: grid; grid-template-columns: 1.2fr 2fr; gap: 48px; padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,.08); }
.foot-brand { display: flex; gap: 12px; align-items: flex-start; }
.foot-brand b { display: block; font-size: 17px; color: #fff; margin-bottom: 6px; }
.foot-brand p { font-size: 13.5px; }

.foot-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.foot-col { display: grid; gap: 10px; align-content: start; }
.foot-col h5 { font-size: 14px; color: #fff; margin-bottom: 4px; }
.foot-col a, .foot-col span { font-size: 13.5px; transition: color .2s; }
.foot-col a:hover { color: var(--cyan); }
.foot-col .muted { color: rgba(255,255,255,.4); }

.footer-bottom {
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  padding-top: 22px; font-size: 13px; color: rgba(255,255,255,.42);
}
.beian a { color: rgba(255, 255, 255, .55); transition: color .2s; }
.beian a:hover { color: var(--cyan); }

/* ---------------- 动画 ---------------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

/* ---------------- 响应式 ---------------- */
@media (max-width: 1080px) {
  .hero-inner { grid-template-columns: 1fr; gap: 48px; }
  .hero-visual { max-width: 520px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .loop { grid-template-columns: repeat(2, 1fr); }
  .loop-item { border-bottom: 1px solid rgba(255, 255, 255, .12); }
  .loop-item:nth-child(2n) { border-right: 0; }
  .loop-item:nth-child(2n)::after { display: none; }
  .loop-item:nth-last-child(-n+1) { border-bottom: 0; }
  .timeline { grid-template-columns: repeat(2, 1fr); }
  .science-extra { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; gap: 28px; }
  .footer-inner { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 900px) {
  .nav-links {
    position: fixed; inset: 72px 0 auto 0; flex-direction: column; gap: 2px;
    padding: 14px 24px 22px; background: rgba(255,255,255,.97);
    backdrop-filter: blur(12px); border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow); transform: translateY(-12px); opacity: 0;
    pointer-events: none; transition: opacity .25s, transform .25s var(--ease);
  }
  .nav-links.open { opacity: 1; transform: none; pointer-events: auto; }
  .nav-links a { color: var(--text) !important; padding: 12px 8px; font-size: 15px; }
  .nav-links a:hover { background: rgba(91,108,255,.08) !important; }
  .nav-toggle { display: flex; }
  .nav-actions .btn-ghost { display: none; }
  .promise { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .wrap, .wrap-narrow { width: calc(100% - 32px); }
  .section { padding: 72px 0; }
  .hero { padding-top: 108px; }
  .grid-3, .grid-4, .timeline, .loop { grid-template-columns: 1fr; }
  .loop-item { border-right: 0; }
  .loop-item::after { display: none; }
  .tab-bar { flex-direction: column; }
  .tab { border-bottom: 1px solid rgba(255, 255, 255, .12); border-left: 2px solid transparent; text-align: left; }
  .tab.active { border-left-color: var(--cyan); border-bottom-color: rgba(255, 255, 255, .12); }
  .tab-panel { padding: 26px 20px; }
  .hero-cta .btn { width: 100%; }
  .footer-bottom { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}