/* ============================================================
   鼎培·知域大陆 — 落地页样式
   墨金 + 宣纸 · 编辑式排版 · 12 栏不对称网格
   ============================================================ */

:root {
  --ink-900: #080b10;
  --ink-800: #0d1015;
  --ink-700: #151a23;
  --ink-600: #1e2531;
  --paper: #f5f0e7;
  --paper-2: #ece3d4;
  --gold: #c9a227;
  --gold-lite: #e6c67d;
  --gold-deep: #9a7615;
  --jade: #56968e;
  --text-dark: #201b14;
  --text-mute: #6c6353;
  --text-light: #ece6da;
  --text-light-mute: #a49d8e;
  --hair-dark: rgba(32, 27, 20, .14);
  --hair-light: rgba(236, 230, 218, .16);
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", STSong, "SimSun", serif;
  --sans: "Noto Sans SC", Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --pad-x: clamp(20px, 5vw, 68px);
  --sec-y: clamp(84px, 11vw, 156px);
  --ease: cubic-bezier(.22, .68, .18, 1);
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--ink-800);
  color: var(--text-light);
  font-family: var(--sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
p { margin: 0 0 1.1em; }
b { font-weight: 700; }

::selection { background: rgba(201, 162, 39, .34); color: #fff; }

.wrap {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 var(--pad-x);
}
.wrap.narrow { max-width: 940px; }

/* ---------- 通用小部件 ---------- */

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 26px;
  font-size: 12.5px;
  letter-spacing: .18em;
  color: var(--gold-lite);
  text-transform: none;
}
.eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, .16);
}

.sec { padding: var(--sec-y) 0; position: relative; }
.sec-paper { background: var(--paper); color: var(--text-dark); }
.sec-ink { background: var(--ink-800); }
.sec-deep { background: var(--ink-900); overflow: hidden; }

.sec-index {
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: .26em;
  color: var(--gold-deep);
  margin: 0 0 22px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--hair-dark);
  max-width: 1320px;
}
.sec-ink .sec-index, .sec-deep .sec-index {
  color: var(--gold-lite);
  border-bottom-color: var(--hair-light);
}

.sec-h2 {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(1.85rem, 3.5vw, 3.05rem);
  line-height: 1.34;
  letter-spacing: -.012em;
  margin: 0 0 26px;
  max-width: 21ch;
}
.sec-lede {
  font-size: clamp(1rem, 1.15vw, 1.12rem);
  line-height: 2.05;
  color: var(--text-mute);
  max-width: 62ch;
  margin: 0 0 clamp(44px, 5vw, 68px);
}
.sec-ink .sec-lede, .sec-deep .sec-lede { color: var(--text-light-mute); }

/* ---------- 按钮 ---------- */

.btn {
  --btn-py: 15px;
  --btn-px: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: var(--btn-py) var(--btn-px);
  border: 1px solid transparent;
  border-radius: 3px;
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .03em;
  line-height: 1.2;
  cursor: pointer;
  transition: transform .32s var(--ease), box-shadow .32s var(--ease),
              background-color .32s var(--ease), border-color .32s var(--ease),
              color .32s var(--ease);
  white-space: nowrap;
}
.btn-sm { --btn-py: 10px; --btn-px: 18px; font-size: 13px; }
.btn-lg { --btn-py: 18px; --btn-px: 38px; font-size: 16.5px; }

.btn-gold {
  background: linear-gradient(135deg, #e9cd88 0%, var(--gold) 52%, #b28a17 100%);
  color: #1b1508;
  box-shadow: 0 10px 30px -14px rgba(201, 162, 39, .85);
}
.btn-gold:hover { transform: translateY(-2px); box-shadow: 0 18px 40px -16px rgba(230, 198, 125, .95); }

.btn-line {
  border-color: var(--hair-light);
  color: var(--text-light);
  background: rgba(255, 255, 255, .02);
}
.btn-line:hover { border-color: rgba(230, 198, 125, .6); color: var(--gold-lite); }

.btn-line-light { border-color: var(--hair-light); color: var(--text-light); }
.btn-line-light:hover { border-color: rgba(230, 198, 125, .65); color: var(--gold-lite); }

.btn-ink { background: var(--ink-800); color: var(--paper); }
.btn-ink:hover { transform: translateY(-2px); background: var(--ink-600); }

.btn-ghost-light {
  border-color: var(--hair-light);
  color: var(--text-light);
  width: 100%;
}

/* ---------- 导航 ---------- */

.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 60;
  transition: background-color .4s var(--ease), border-color .4s var(--ease),
              backdrop-filter .4s var(--ease);
  border-bottom: 1px solid transparent;
}
.nav.is-stuck {
  background: rgba(8, 11, 16, .88);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom-color: var(--hair-light);
}
.nav-inner {
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 var(--pad-x);
  height: 76px;
  display: flex;
  align-items: center;
  gap: 32px;
}
.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 34px; height: 34px;
  display: grid; place-items: center;
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 900;
  color: #1b1508;
  background: linear-gradient(140deg, #e9cd88, var(--gold-deep));
  clip-path: polygon(50% 0, 93% 25%, 93% 75%, 50% 100%, 7% 75%, 7% 25%);
}
.brand-text { font-family: var(--serif); font-size: 18px; letter-spacing: .02em; }
.brand-text b { font-weight: 900; }
.brand-text i { font-style: normal; font-weight: 500; color: var(--text-light-mute); font-size: 15px; }

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.1vw, 34px);
  margin-left: auto;
  font-size: 14.5px;
  color: rgba(236, 230, 218, .78);
}
.nav-links a { position: relative; padding: 6px 0; transition: color .3s var(--ease); }
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%; bottom: 0;
  height: 1px;
  background: var(--gold);
  transition: right .38s var(--ease);
}
.nav-links a:hover { color: var(--gold-lite); }
.nav-links a:hover::after { right: 0; }

.nav-cta { display: flex; align-items: center; gap: 12px; }

.burger {
  display: none;
  width: 42px; height: 42px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  padding: 0;
  background: transparent;
  border: 1px solid var(--hair-light);
  border-radius: 3px;
  cursor: pointer;
}
.burger span {
  width: 17px; height: 1.5px;
  background: var(--text-light);
  transition: transform .3s var(--ease), opacity .3s var(--ease);
}
.burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* 右侧抽屉 */
.drawer-backdrop {
  position: fixed; inset: 0; z-index: 70;
  background: rgba(5, 7, 10, .62);
  backdrop-filter: blur(2px);
  opacity: 0;
  transition: opacity .34s var(--ease);
}
.drawer-backdrop.is-open { opacity: 1; }

.drawer {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  z-index: 80;
  width: min(354px, 86vw);
  padding: 26px 26px 34px;
  background: var(--ink-700);
  border-left: 1px solid var(--hair-light);
  transform: translateX(101%);
  transition: transform .42s var(--ease);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}
.drawer.is-open { transform: none; }
.drawer-head {
  display: flex; align-items: center; justify-content: space-between;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--hair-light);
}
.drawer-close {
  width: 34px; height: 34px;
  font-size: 22px; line-height: 1;
  color: var(--text-light-mute);
  background: transparent;
  border: 1px solid var(--hair-light);
  border-radius: 3px;
  cursor: pointer;
}
.drawer-links { display: flex; flex-direction: column; padding: 10px 0 26px; flex: 1; }
.drawer-links a {
  font-family: var(--serif);
  font-size: 19px;
  padding: 15px 2px;
  border-bottom: 1px solid rgba(236, 230, 218, .08);
  color: rgba(236, 230, 218, .86);
}
.drawer-links a:active { color: var(--gold-lite); }
.drawer-foot { display: flex; flex-direction: column; gap: 12px; }

/* ---------- HERO ---------- */

.hero {
  position: relative;
  padding: clamp(126px, 15vw, 176px) 0 clamp(72px, 8vw, 112px);
  background: var(--ink-900);
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: -6% -4%;
  background: url("./img/hero-art.jpg") center 34% / cover no-repeat;
  opacity: .3;
  filter: saturate(.82);
  animation: heroDrift 46s ease-in-out infinite alternate;
}
.hero-veil {
  position: absolute; inset: 0;
  background:
    radial-gradient(120% 90% at 18% 12%, rgba(8, 11, 16, .34) 0%, rgba(8, 11, 16, .93) 62%, #080b10 100%),
    linear-gradient(180deg, rgba(8, 11, 16, .9) 0%, rgba(8, 11, 16, .18) 34%, rgba(8, 11, 16, .96) 100%);
}
@keyframes heroDrift {
  from { transform: scale(1.03) translate3d(0, 0, 0); }
  to   { transform: scale(1.1) translate3d(-1.6%, -1.2%, 0); }
}
.hero-grid {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
  gap: clamp(40px, 5vw, 84px);
  align-items: center;
}
.hero-h1 {
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(1.85rem, 3.1vw, 2.8rem);
  line-height: 1.46;
  letter-spacing: -.01em;
  margin: 0 0 30px;
}
.hero-h1 em {
  font-style: normal;
  font-weight: 900;
  color: var(--gold-lite);
  background: linear-gradient(transparent 76%, rgba(201, 162, 39, .3) 76%);
}
.hero-h1-strong {
  display: inline-block;
  font-weight: 900;
  font-size: 1.2em;
  line-height: 1.24;
  color: #fff;
}
.hero-lede {
  max-width: 46ch;
  font-size: clamp(1rem, 1.12vw, 1.1rem);
  line-height: 2.05;
  color: rgba(236, 230, 218, .74);
  margin-bottom: 40px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: clamp(44px, 5vw, 62px); }

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  margin: 0;
  padding-top: 28px;
  border-top: 1px solid var(--hair-light);
}
.hero-stats > div { padding: 0 clamp(8px, 1.4vw, 20px); }
.hero-stats > div:first-child { padding-left: 0; }
.hero-stats > div + div { border-left: 1px solid var(--hair-light); }
.hero-stats dt {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(1.7rem, 2.7vw, 2.35rem);
  line-height: 1.1;
  color: var(--gold-lite);
}
.hero-stats dd {
  margin: 8px 0 0;
  font-size: 12.5px;
  letter-spacing: .05em;
  color: var(--text-light-mute);
}
.stat-zero { color: #fff !important; }

.scroll-hint {
  position: relative;
  z-index: 2;
  display: inline-block;
  margin-top: clamp(48px, 6vw, 76px);
  font-size: 12px;
  letter-spacing: .22em;
  color: rgba(236, 230, 218, .45);
  border-left: 1px solid var(--hair-light);
  padding-left: 14px;
}
.scroll-hint:hover { color: var(--gold-lite); }

/* 截图框 */
.shot-frame {
  position: relative;
  border: 1px solid rgba(230, 198, 125, .22);
  border-radius: 6px;
  overflow: hidden;
  background: var(--ink-700);
  box-shadow: 0 40px 90px -40px rgba(0, 0, 0, .92),
              0 0 0 6px rgba(255, 255, 255, .018);
  transition: transform .5s var(--ease), box-shadow .5s var(--ease);
}
.shot-frame::after {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(148deg, rgba(255, 255, 255, .1) 0%, rgba(255, 255, 255, 0) 34%);
  pointer-events: none;
}
.shot-frame img { width: 100%; }
.hero-shot:hover .shot-frame { transform: translateY(-6px); box-shadow: 0 54px 110px -44px rgba(0, 0, 0, .95); }

.shot-caption {
  margin-top: 18px;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--text-light-mute);
}
.sec-paper .shot-caption { color: var(--text-mute); }
.cap-tag {
  display: inline-block;
  margin-right: 8px;
  padding: 3px 9px;
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--gold-lite);
  border: 1px solid rgba(230, 198, 125, .3);
  border-radius: 2px;
  vertical-align: 1px;
}
.sec-paper .cap-tag { color: var(--gold-deep); border-color: rgba(154, 118, 21, .34); }

/* ---------- 01 痛点 ---------- */

.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  margin-bottom: clamp(60px, 7vw, 96px);
}
.pain {
  padding: 6px clamp(22px, 2.6vw, 40px) 0;
  border-left: 1px solid var(--hair-dark);
}
.pain:first-child { padding-left: 0; border-left: 0; }
.pain-no {
  display: block;
  font-family: var(--serif);
  font-size: 34px;
  font-weight: 900;
  color: rgba(154, 118, 21, .34);
  line-height: 1;
  margin-bottom: 22px;
}
.pain h3 {
  font-family: var(--serif);
  font-size: clamp(1.12rem, 1.5vw, 1.32rem);
  font-weight: 700;
  margin: 0 0 14px;
  line-height: 1.5;
}
.pain p { font-size: 15.5px; line-height: 2; color: var(--text-mute); margin: 0; }

.pull {
  position: relative;
  margin: 0;
  padding: clamp(28px, 3vw, 44px) clamp(24px, 3vw, 52px);
  border-left: 3px solid var(--gold);
  background: linear-gradient(90deg, rgba(201, 162, 39, .07), rgba(201, 162, 39, 0) 62%);
  font-family: var(--serif);
  font-size: clamp(1.25rem, 2.35vw, 1.95rem);
  font-weight: 700;
  line-height: 1.72;
  letter-spacing: -.005em;
  max-width: 34ch;
}
.pull cite {
  display: block;
  margin-top: 18px;
  font-family: var(--sans);
  font-size: 13.5px;
  font-style: normal;
  letter-spacing: .04em;
  color: var(--text-mute);
}

/* ---------- 02 孩子屏 ---------- */

.feat-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(38px, 4vw, 64px);
  margin-bottom: clamp(64px, 7vw, 96px);
}
.feat { grid-column: span 4; }
.feat-wide {
  grid-column: span 12;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
  gap: clamp(36px, 4.4vw, 72px);
  align-items: center;
  padding-bottom: clamp(48px, 5vw, 72px);
  border-bottom: 1px solid var(--hair-light);
}
.feat-kicker {
  display: inline-block;
  margin-bottom: 14px;
  font-size: 12px;
  letter-spacing: .2em;
  color: var(--gold);
}
.feat h3, .band h3 {
  font-family: var(--serif);
  font-size: clamp(1.15rem, 1.75vw, 1.5rem);
  font-weight: 700;
  line-height: 1.55;
  margin: 0 0 16px;
}
.feat-wide h3 { font-size: clamp(1.35rem, 2.3vw, 2rem); }
.feat p, .band p {
  font-size: 15.5px;
  line-height: 2;
  color: var(--text-light-mute);
  margin: 0;
}
.feat-list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}
.feat-list li {
  position: relative;
  padding: 11px 0 11px 22px;
  border-top: 1px solid var(--hair-light);
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(236, 230, 218, .8);
}
.feat-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 20px;
  width: 8px; height: 8px;
  border: 1px solid var(--gold);
  transform: rotate(45deg);
}
.feat .feat-shot { margin-bottom: 24px; }
.feat-wide .feat-shot { margin: 0; }
.feat-shot img { display: block; width: 100%; height: auto; border-radius: 4px; }

.band {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
  gap: clamp(34px, 4vw, 64px);
  align-items: center;
  padding: clamp(32px, 3.6vw, 58px);
  border: 1px solid var(--hair-light);
  border-radius: 6px;
  background:
    linear-gradient(120deg, rgba(30, 37, 49, .96), rgba(13, 16, 21, .96)),
    url("./img/band-mech.jpg") center / cover no-repeat;
}
.band h3 { font-size: clamp(1.3rem, 2.1vw, 1.8rem); }
.band p { max-width: 52ch; }
.band p + p { margin-top: 14px; }
.band-note {
  margin-top: 24px !important;
  padding-top: 18px;
  border-top: 1px solid var(--hair-light);
  font-size: 13.5px !important;
  color: rgba(230, 198, 125, .78) !important;
}
.band-shot {
  border-radius: 6px;
  overflow: hidden;
  border: 1px solid rgba(230, 198, 125, .2);
  box-shadow: 0 34px 70px -34px rgba(0, 0, 0, .9);
  max-height: 460px;
}
.band-shot img { width: 100%; height: 100%; object-fit: cover; object-position: center 22%; }

/* ---------- 03 家长端 ---------- */

.split {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(0, .96fr);
  gap: clamp(40px, 5vw, 88px);
  align-items: start;
}
.split-copy .sec-lede { margin-bottom: 38px; }
.split-shot { position: sticky; top: 108px; margin: 0; }

.check-list { list-style: none; margin: 0 0 40px; padding: 0; }
.check-list li {
  position: relative;
  padding: 18px 0 18px 40px;
  border-top: 1px solid var(--hair-dark);
  font-size: 15.5px;
  line-height: 1.95;
  color: var(--text-mute);
}
.check-list li b {
  display: block;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 4px;
}
.check-list li::before {
  content: "";
  position: absolute;
  left: 2px; top: 26px;
  width: 11px; height: 6px;
  border-left: 1.6px solid var(--gold-deep);
  border-bottom: 1.6px solid var(--gold-deep);
  transform: rotate(-45deg);
}
.inline-cta { display: flex; align-items: center; flex-wrap: wrap; gap: 18px; }
.cta-hint { font-size: 13px; color: var(--text-mute); }

/* ---------- 04 底线 ---------- */

.sec-deep::before {
  content: "";
  position: absolute; inset: 0;
  background: url("./img/band-mech.jpg") center / cover no-repeat;
  opacity: .1;
  pointer-events: none;
}
.sec-deep .wrap { position: relative; }

.rule-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--hair-light);
}
.rule {
  padding: clamp(28px, 2.8vw, 40px) clamp(20px, 2.2vw, 32px);
  border-left: 1px solid var(--hair-light);
  transition: background-color .45s var(--ease);
}
.rule:first-child { border-left: 0; padding-left: 0; }
.rule:hover { background: rgba(255, 255, 255, .022); }
.rule-no {
  display: block;
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: .2em;
  color: var(--gold);
  margin-bottom: 20px;
}
.rule h3 {
  font-family: var(--serif);
  font-size: clamp(1.12rem, 1.5vw, 1.3rem);
  font-weight: 700;
  margin: 0 0 14px;
  color: #fff;
}
.rule p { font-size: 14.5px; line-height: 2; color: var(--text-light-mute); margin: 0 0 22px; }
.rule-foot {
  display: block;
  padding-top: 14px;
  border-top: 1px dashed rgba(236, 230, 218, .14);
  font-size: 12.5px;
  letter-spacing: .04em;
  color: rgba(230, 198, 125, .8);
}

/* ---------- 05 内容与年级 ---------- */

.table-wrap {
  overflow-x: auto;
  margin-bottom: 22px;
  border-top: 1px solid var(--hair-dark);
  border-bottom: 1px solid var(--hair-dark);
}
.grade-table {
  width: 100%;
  min-width: 720px;
  border-collapse: collapse;
  text-align: left;
}
.grade-table th {
  padding: 16px 22px 16px 0;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .16em;
  color: var(--text-mute);
  border-bottom: 1px solid var(--hair-dark);
  white-space: nowrap;
}
.grade-table td {
  padding: 22px 22px 22px 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-mute);
  border-bottom: 1px solid rgba(32, 27, 20, .07);
  vertical-align: top;
}
.grade-table tbody tr:last-child td { border-bottom: 0; }
.grade-table td:first-child { color: var(--text-dark); font-size: 16px; white-space: nowrap; }
.grade-table td:nth-child(3) {
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 700;
  color: var(--gold-deep);
  white-space: nowrap;
}
.grade-table tbody tr { transition: background-color .35s var(--ease); }
.grade-table tbody tr:hover { background: rgba(201, 162, 39, .05); }
.table-note { font-size: 13px; color: var(--text-mute); margin-bottom: clamp(56px, 6vw, 84px); }

.three-steps ol {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(24px, 3vw, 48px);
  list-style: none;
  margin: 0;
  padding: 0;
}
.three-steps h3 {
  font-family: var(--serif);
  font-size: clamp(1.2rem, 1.9vw, 1.6rem);
  font-weight: 700;
  margin: 0 0 30px;
}
.three-steps li {
  padding-top: 24px;
  border-top: 2px solid var(--gold);
  font-size: 15px;
  line-height: 1.95;
  color: var(--text-mute);
}
.three-steps li span {
  display: block;
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 900;
  color: rgba(154, 118, 21, .32);
  line-height: 1;
  margin-bottom: 14px;
}
.three-steps li b {
  display: block;
  font-family: var(--serif);
  font-size: 17px;
  color: var(--text-dark);
  margin-bottom: 8px;
}

/* ---------- 06 FAQ ---------- */

.sec-faq { padding-top: 0; }
.faq-list { border-top: 1px solid var(--hair-dark); }
.faq { border-bottom: 1px solid var(--hair-dark); }
.faq summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 26px 0;
  font-family: var(--serif);
  font-size: clamp(1.02rem, 1.5vw, 1.24rem);
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  transition: color .3s var(--ease);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary:hover { color: var(--gold-deep); }
.faq-mark {
  position: relative;
  flex: 0 0 18px;
  width: 18px; height: 18px;
  transition: transform .35s var(--ease);
}
.faq-mark::before, .faq-mark::after {
  content: "";
  position: absolute;
  left: 0; top: 8px;
  width: 18px; height: 1.5px;
  background: var(--gold-deep);
}
.faq-mark::after { transform: rotate(90deg); transition: opacity .3s var(--ease); }
.faq[open] .faq-mark { transform: rotate(180deg); }
.faq[open] .faq-mark::after { opacity: 0; }
.faq-body { padding: 0 0 28px; max-width: 74ch; }
.faq-body p { font-size: 15.5px; line-height: 2.05; color: var(--text-mute); margin: 0; }

/* ---------- CTA ---------- */

.cta {
  position: relative;
  padding: clamp(96px, 12vw, 168px) 0;
  background: var(--ink-900);
  text-align: center;
  overflow: hidden;
}
.cta-bg {
  position: absolute; inset: 0;
  background: url("./img/hero-art.jpg") center / cover no-repeat;
  opacity: .22;
}
.cta-bg::after {
  content: "";
  position: absolute; inset: 0;
  background: radial-gradient(90% 120% at 50% 100%, rgba(201, 162, 39, .2) 0%, rgba(8, 11, 16, .96) 62%);
}
.cta-inner { position: relative; z-index: 2; }
.cta-h2 {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(1.9rem, 4vw, 3.4rem);
  line-height: 1.4;
  letter-spacing: -.01em;
  margin: 0 0 22px;
}
.cta-p { font-size: clamp(1rem, 1.3vw, 1.16rem); color: rgba(236, 230, 218, .74); margin-bottom: 42px; }
.cta-actions {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 28px;
}
.cta-fine { font-size: 13px; color: rgba(236, 230, 218, .48); margin: 0; }

/* ---------- 页脚 ---------- */

.foot { background: #05070a; border-top: 1px solid var(--hair-light); padding: clamp(52px, 6vw, 76px) 0 30px; }
.foot-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) repeat(3, minmax(0, 1fr));
  gap: clamp(28px, 4vw, 56px);
  padding-bottom: 46px;
  border-bottom: 1px solid var(--hair-light);
}
.foot-brand { display: flex; gap: 16px; }
.foot-brand .brand-mark { flex: 0 0 34px; margin-top: 4px; }
.foot-brand b { font-family: var(--serif); font-size: 17px; font-weight: 900; }
.foot-brand p { margin: 10px 0 0; font-size: 13.5px; line-height: 1.9; color: var(--text-light-mute); max-width: 34ch; }
.foot-col h4 {
  margin: 0 0 16px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .18em;
  color: rgba(230, 198, 125, .8);
}
.foot-col a {
  display: block;
  padding: 6px 0;
  font-size: 14px;
  color: rgba(236, 230, 218, .7);
  transition: color .3s var(--ease);
}
.foot-col a:hover { color: var(--gold-lite); }
.foot-note { font-size: 12.5px; line-height: 1.95; color: rgba(236, 230, 218, .48); margin: 0; }
.foot-base {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding-top: 26px;
  font-size: 12.5px;
  letter-spacing: .06em;
  color: rgba(236, 230, 218, .38);
}

/* ---------- 出场动画 ---------- */

html.js .reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .9s var(--ease), transform .9s var(--ease);
}
html.js .reveal.in { opacity: 1; transform: none; }
html.js .feat:nth-child(2).reveal { transition-delay: .1s; }
html.js .feat:nth-child(3).reveal { transition-delay: .18s; }
html.js .feat:nth-child(4).reveal { transition-delay: .26s; }
html.js .rule:nth-child(2).reveal { transition-delay: .1s; }
html.js .rule:nth-child(3).reveal { transition-delay: .18s; }
html.js .rule:nth-child(4).reveal { transition-delay: .26s; }

/* ---------- 响应式 ---------- */

@media (max-width: 1180px) {
  .nav-links { display: none; }
  .burger { display: flex; }
  .rule-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .rule { padding-left: 0; border-left: 0; }
  .rule:nth-child(even) { padding-left: clamp(20px, 3vw, 36px); border-left: 1px solid var(--hair-light); }
}

@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr); }
  .hero-shot { max-width: 620px; }
  .split { grid-template-columns: minmax(0, 1fr); }
  .split-shot { position: static; max-width: 620px; }
  .feat { grid-column: span 6; }
  .feat-wide { grid-template-columns: minmax(0, 1fr); gap: 34px; }
  .band { grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); }
}

@media (max-width: 780px) {
  .pain-grid { grid-template-columns: minmax(0, 1fr); gap: 34px; }
  .pain { padding: 0 0 0 22px; border-left: 2px solid rgba(201, 162, 39, .38); }
  .pain:first-child { padding-left: 22px; }
  .hero-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); row-gap: 26px; }
  .hero-stats > div:nth-child(3) { padding-left: 0; border-left: 0; }
  .hero-h1 { font-size: clamp(1.7rem, 7.2vw, 2.3rem); line-height: 1.5; }
  .three-steps ol { grid-template-columns: minmax(0, 1fr); }
  .feat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: clamp(28px, 4.4vw, 44px); }
  .feat { grid-column: span 1; }
  .feat-wide { grid-column: span 2; }
  .band { grid-template-columns: minmax(0, 1fr); }
  .band-shot { max-height: 320px; }
  .foot-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .nav-inner { height: 66px; gap: 12px; }
  .brand-text i { display: none; }
  .nav-cta .btn { display: none; }
  .hero { padding-top: 108px; }
  .hero-actions .btn { width: 100%; }
  .feat-grid { grid-template-columns: minmax(0, 1fr); gap: 40px; }
  .feat, .feat-wide { grid-column: auto; }
  .rule-grid { grid-template-columns: minmax(0, 1fr); }
  .rule { border-left: 0; padding: 24px 0; border-top: 1px solid var(--hair-light); }
  .rule:nth-child(even) { padding-left: 0; border-left: 0; }
  .rule:first-child { border-top: 0; }
  .cta-actions .btn { width: 100%; }
  .foot-grid { grid-template-columns: minmax(0, 1fr); }
  .scroll-hint { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .hero-bg { animation: none; }
  html.js .reveal { opacity: 1; transform: none; transition: none; }
  .btn, .shot-frame, .rule, .grade-table tbody tr { transition: none; }
  .hero-shot:hover .shot-frame { transform: none; }
}