/* ============================================================
 * 老阳建站 · 案例陈列馆
 * 设计系统 style.css
 * 目录：
 *  01 设计变量    02 基础重置    03 通用组件
 *  04 顶部公告    05 导航        06 首屏 Hero
 *  07 信任条      08 服务        09 案例（核心）
 *  10 企业服务    11 为什么免费   12 流程
 *  13 FAQ         14 关于我      15 转化区
 *  16 页脚        17 直播模式    18 自动演示
 *  19 响应式
 * ============================================================ */

/* ------------------------------------------------------------
 * 01 设计变量
 * ---------------------------------------------------------- */
:root {
  /* 品牌色 */
  --brand:          #2563EB;
  --brand-600:      #1D4ED8;
  --brand-700:      #1E40AF;
  --brand-050:      #EFF6FF;
  --brand-100:      #DBEAFE;
  --brand-glow:     rgba(37, 99, 235, .35);

  /* 中性色 */
  --ink:            #0F172A;
  --ink-2:          #475569;
  --ink-3:          #94A3B8;
  --line:           #E2E8F0;
  --line-soft:      #F1F5F9;
  --bg:             #F8FAFC;
  --surface:        #FFFFFF;

  /* 深色区 */
  --dark:           #070B16;
  --dark-2:         #0E1526;
  --dark-3:         #17203A;
  --dark-line:      rgba(148, 163, 184, .16);
  --dark-text:      #E8EEF9;
  --dark-sub:       #94A3B8;

  /* 语义色 */
  --ok:             #16A34A;
  --ok-bg:          #DCFCE7;
  --warn:           #F59E0B;
  --warn-bg:        #FEF3C7;
  --violet:         #7C3AED;
  --rose:           #DB2777;
  --cyan:           #06B6D4;

  /* 圆角 */
  --r-xs: 6px;
  --r-sm: 10px;
  --r:    16px;
  --r-lg: 22px;
  --r-xl: 30px;
  --r-full: 999px;

  /* 阴影 */
  --sh-1: 0 1px 2px rgba(15, 23, 42, .06);
  --sh-2: 0 6px 18px -6px rgba(15, 23, 42, .12);
  --sh-3: 0 16px 40px -16px rgba(15, 23, 42, .20);
  --sh-4: 0 30px 70px -24px rgba(15, 23, 42, .30);

  /* 8pt 间距 */
  --sp-1: 8px;  --sp-2: 16px; --sp-3: 24px; --sp-4: 32px;
  --sp-5: 40px; --sp-6: 56px; --sp-7: 80px; --sp-8: 112px;

  /* 动效 */
  --ease: cubic-bezier(.22, 1, .36, 1);
  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --t-fast: .16s;
  --t: .28s;
  --t-slow: .6s;

  --maxw: 1200px;
  --nav-h: 68px;
}

/* ------------------------------------------------------------
 * 02 基础重置
 * ---------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "PingFang SC", "HarmonyOS Sans SC",
               "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 { margin: 0; line-height: 1.25; font-weight: 800; letter-spacing: -.01em; }
p { margin: 0; }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }
button { font: inherit; cursor: pointer; border: 0; background: none; color: inherit; }

::selection { background: var(--brand); color: #fff; }

:focus-visible {
  outline: 3px solid var(--brand);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ------------------------------------------------------------
 * 03 通用组件
 * ---------------------------------------------------------- */
.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: var(--sp-8) 0; position: relative; }
.section--tight { padding: var(--sp-7) 0; }
.section--dark { background: var(--dark); color: var(--dark-text); }
.section--soft { background: var(--surface); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 14px;
}
.eyebrow::before {
  content: "";
  width: 22px; height: 2px;
  background: currentColor;
  border-radius: 2px;
}
.section--dark .eyebrow { color: #60A5FA; }

.h-sec {
  font-size: clamp(26px, 3.4vw, 40px);
  letter-spacing: -.02em;
}
.sub-sec {
  margin-top: 16px;
  font-size: 17px;
  color: var(--ink-2);
  max-width: 720px;
  line-height: 1.85;
}
.section--dark .sub-sec { color: var(--dark-sub); }

.sec-head { margin-bottom: var(--sp-7); }
.sec-head--center { text-align: center; }
.sec-head--center .sub-sec { margin-left: auto; margin-right: auto; }
.sec-head--center .eyebrow { justify-content: center; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 48px;
  padding: 0 24px;
  border-radius: var(--r-full);
  font-size: 15px;
  font-weight: 700;
  white-space: nowrap;
  transition: transform var(--t-fast) var(--ease),
              box-shadow var(--t) var(--ease),
              background var(--t) var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 10px 26px -10px var(--brand-glow);
}
.btn--primary:hover { background: var(--brand-600); box-shadow: 0 16px 34px -12px var(--brand-glow); }

.btn--ghost {
  border: 1.5px solid var(--line);
  background: var(--surface);
  color: var(--ink);
}
.btn--ghost:hover { border-color: var(--brand); color: var(--brand); box-shadow: var(--sh-2); }

.btn--onDark {
  border: 1.5px solid rgba(148, 163, 184, .35);
  color: var(--dark-text);
  background: rgba(255, 255, 255, .04);
}
.btn--onDark:hover { border-color: #93C5FD; background: rgba(255, 255, 255, .09); }

.btn--lg { height: 56px; padding: 0 32px; font-size: 16px; }
.btn--block { width: 100%; }

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 26px;
  padding: 0 10px;
  border-radius: var(--r-full);
  font-size: 12px;
  font-weight: 600;
  background: var(--brand-050);
  color: var(--brand-600);
  border: 1px solid var(--brand-100);
  white-space: nowrap;
}
.tag--free { background: var(--ok-bg); color: #15803D; border-color: #BBF7D0; }
.tag--dark { background: rgba(37, 99, 235, .16); color: #93C5FD; border-color: rgba(96, 165, 250, .3); }
.tag--gray { background: var(--line-soft); color: var(--ink-2); border-color: var(--line); }

/* 卡片 */
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 32px;
  transition: transform var(--t) var(--ease),
              box-shadow var(--t) var(--ease),
              border-color var(--t) var(--ease);
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--sh-3);
  border-color: var(--brand-100);
}

/* 滚动淡入 */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .7s var(--ease-out), transform .7s var(--ease-out);
  transition-delay: var(--d, 0ms);
  will-change: opacity, transform;
}
.reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}

/* ------------------------------------------------------------
 * 04 顶部公告条
 * ---------------------------------------------------------- */
.topbar {
  background: linear-gradient(90deg, var(--brand-700), var(--brand), #4F46E5);
  color: #fff;
  font-size: 13.5px;
  font-weight: 600;
  text-align: center;
  padding: 9px 16px;
  letter-spacing: .01em;
}
.topbar b { font-weight: 800; }
.topbar .dot {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: #4ADE80;
  margin-right: 7px;
  vertical-align: middle;
  box-shadow: 0 0 0 0 rgba(74, 222, 128, .7);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  70% { box-shadow: 0 0 0 9px rgba(74, 222, 128, 0); }
  100% { box-shadow: 0 0 0 0 rgba(74, 222, 128, 0); }
}

/* ------------------------------------------------------------
 * 05 导航
 * ---------------------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.nav.is-stuck {
  border-bottom-color: var(--line);
  box-shadow: 0 4px 24px -12px rgba(15, 23, 42, .18);
}
.nav__inner {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: 28px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -.01em;
  flex-shrink: 0;
}
.logo__mark {
  width: 34px; height: 34px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--brand), #7C3AED);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 16px;
  font-weight: 800;
  box-shadow: 0 6px 16px -6px var(--brand-glow);
}
.logo__sub {
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-3);
  letter-spacing: .02em;
}

.nav__menu {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}
.nav__link {
  position: relative;
  padding: 8px 13px;
  font-size: 14.5px;
  font-weight: 600;
  white-space: nowrap;
  color: var(--ink-2);
  border-radius: var(--r-sm);
  transition: color var(--t-fast), background var(--t-fast);
}
.nav__link:hover { color: var(--brand); background: var(--brand-050); }
.nav__link.is-active { color: var(--brand); }
.nav__link.is-active::after {
  content: "";
  position: absolute;
  left: 14px; right: 14px; bottom: 2px;
  height: 2px;
  background: var(--brand);
  border-radius: 2px;
}

.nav__actions { display: flex; align-items: center; gap: 10px; margin-left: 12px; }
.nav__tools { display: flex; align-items: center; gap: 6px; }
.tool-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 34px;
  padding: 0 12px;
  border-radius: var(--r-full);
  font-size: 12.5px;
  font-weight: 700;
  white-space: nowrap;
  color: var(--ink-2);
  border: 1px solid var(--line);
  background: var(--surface);
  transition: all var(--t-fast) var(--ease);
}
.tool-btn:hover { border-color: var(--brand); color: var(--brand); }
.tool-btn[aria-pressed="true"] {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

.burger {
  display: none;
  width: 40px; height: 40px;
  border-radius: var(--r-sm);
  border: 1px solid var(--line);
  background: var(--surface);
  /* 用 place-content 把三条杠整体居中，行距固定为 row-gap。
     这样翻"叉"时 translateY 的值就等于杠间距（2+4=6px），不会错位成">"。 */
  place-content: center;
  row-gap: 4px;
}
.burger span {
  display: block;
  width: 18px; height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform var(--t) var(--ease), opacity var(--t);
}
.nav.is-open .burger span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav.is-open .burger span:nth-child(2) { opacity: 0; }
.nav.is-open .burger span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ------------------------------------------------------------
 * 06 首屏 Hero
 * ---------------------------------------------------------- */
.hero {
  position: relative;
  background: var(--dark);
  color: var(--dark-text);
  overflow: hidden;
  padding: 88px 0 96px;
  isolation: isolate;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--dark-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--dark-line) 1px, transparent 1px);
  background-size: 68px 68px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 75%);
  z-index: -1;
}
.hero::after {
  content: "";
  position: absolute;
  width: 900px; height: 620px;
  top: -300px; left: 50%;
  transform: translateX(-50%);
  background: radial-gradient(circle, rgba(37, 99, 235, .40), transparent 62%);
  filter: blur(40px);
  z-index: -1;
  animation: float 14s ease-in-out infinite;
}
@keyframes float {
  50% { transform: translateX(-50%) translateY(38px) scale(1.06); }
}

.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  gap: 64px;
  align-items: center;
}
.hero__grid > * { min-width: 0; }

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 16px 7px 8px;
  border-radius: var(--r-full);
  background: rgba(255, 255, 255, .06);
  border: 1px solid rgba(148, 163, 184, .24);
  font-size: 13px;
  font-weight: 600;
  color: #CBD5E1;
  margin-bottom: 26px;
  backdrop-filter: blur(8px);
}
.hero__badge i {
  font-style: normal;
  padding: 3px 10px;
  border-radius: var(--r-full);
  background: linear-gradient(135deg, var(--brand), #6366F1);
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .04em;
}

.hero__title {
  font-size: clamp(31px, 4.15vw, 53px);
  line-height: 1.16;
  letter-spacing: -.03em;
  font-weight: 800;
  text-wrap: balance;
}
.hero__title em {
  font-style: normal;
  background: linear-gradient(120deg, #60A5FA 0%, #A78BFA 50%, #22D3EE 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__desc {
  margin-top: 24px;
  font-size: 17.5px;
  line-height: 1.85;
  color: #A9B7CE;
  max-width: 560px;
}
.hero__desc b { color: #fff; font-weight: 700; }

.hero__points {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 30px;
}
.hero__point {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 34px;
  padding: 0 14px;
  border-radius: var(--r-full);
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(148, 163, 184, .2);
  font-size: 13px;
  font-weight: 600;
  color: #D5DEEB;
}
.hero__point svg { color: #4ADE80; flex-shrink: 0; }

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.hero__stats {
  display: flex;
  gap: 40px;
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--dark-line);
}
.hero__stat b {
  display: block;
  font-size: 30px;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -.02em;
  background: linear-gradient(180deg, #fff, #9CB3D6);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero__stat span { font-size: 13px; color: var(--dark-sub); }

/* Hero 右侧：浏览器窗口演示 */
.hero__visual { position: relative; }
.hero__visual .glow {
  position: absolute;
  inset: -14% -8%;
  background: radial-gradient(circle at 60% 40%, rgba(99, 102, 241, .32), transparent 65%);
  filter: blur(30px);
  z-index: -1;
}

.win {
  border-radius: var(--r-lg);
  overflow: hidden;
  background: #101827;
  border: 1px solid rgba(148, 163, 184, .22);
  box-shadow: var(--sh-4), 0 0 0 1px rgba(255, 255, 255, .04) inset;
  transform: perspective(1400px) rotateY(-7deg) rotateX(3deg);
  transition: transform var(--t-slow) var(--ease);
}
.hero__visual:hover .win { transform: perspective(1400px) rotateY(-2deg) rotateX(0); }
.win__bar {
  height: 34px;
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 0 14px;
  background: #0B1220;
  border-bottom: 1px solid rgba(148, 163, 184, .16);
}
.win__bar i { width: 10px; height: 10px; border-radius: 50%; background: #334155; }
.win__bar i:nth-child(1) { background: #F87171; }
.win__bar i:nth-child(2) { background: #FBBF24; }
.win__bar i:nth-child(3) { background: #34D399; }
.win__url {
  margin-left: 12px;
  flex: 1;
  min-width: 0;
  height: 20px;
  border-radius: var(--r-full);
  background: rgba(148, 163, 184, .12);
  font-size: 11px;
  color: #64748B;
  display: flex;
  align-items: center;
  padding: 0 12px;
  letter-spacing: .02em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.win__body { height: 372px; position: relative; overflow: hidden; }

/* 首屏窗口里轮播的案例预览图
   内容不是写死的，由 main.js 的 initHeroSlider() 用真实案例数据生成，
   轮播 官网 / 小程序 / 后台系统 各一个，3 秒读懂"我做过什么"。 */
.slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity .9s var(--ease);
  padding: 22px 20px;
  display: grid;
  place-items: center;
}
.slide.is-on { opacity: 1; }
.slide .mk-wrap { width: 100%; }
.slide .mk-phones { height: 100%; }

/* 浮动小卡片 */
.float-card {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: var(--r);
  background: rgba(255, 255, 255, .96);
  box-shadow: var(--sh-4);
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  animation: bob 6s ease-in-out infinite;
}
.float-card small { display: block; font-size: 11.5px; font-weight: 500; color: var(--ink-3); }
.float-card--a { left: -26px; top: 16%; animation-delay: -1s; }
.float-card--b { right: -22px; bottom: 14%; animation-delay: -3s; }
.float-card__ico {
  width: 32px; height: 32px;
  border-radius: 9px;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 15px;
  flex-shrink: 0;
}
@keyframes bob {
  50% { transform: translateY(-12px); }
}

/* ------------------------------------------------------------
 * 07 信任条（跑马灯）
 * ---------------------------------------------------------- */
.trust {
  border-top: 1px solid var(--dark-line);
  border-bottom: 1px solid var(--dark-line);
  background: #05080F;
  overflow: hidden;
  padding: 18px 0;
}
.marquee { display: flex; width: max-content; animation: scroll-x 34s linear infinite; }
.trust:hover .marquee { animation-play-state: paused; }
@keyframes scroll-x {
  to { transform: translateX(-50%); }
}
.marquee__item {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 0 34px;
  font-size: 14px;
  font-weight: 600;
  color: #7E8DA6;
  white-space: nowrap;
}
.marquee__item::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--brand);
  opacity: .7;
}

/* ------------------------------------------------------------
 * 08 服务
 * ---------------------------------------------------------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 26px; }

.svc { display: flex; flex-direction: column; }
.svc__ico {
  width: 52px; height: 52px;
  border-radius: 15px;
  display: grid;
  place-items: center;
  color: #fff;
  margin-bottom: 22px;
  box-shadow: var(--sh-2);
}
.svc__ico--1 { background: linear-gradient(135deg, #2563EB, #4F46E5); }
.svc__ico--2 { background: linear-gradient(135deg, #0EA5E9, #06B6D4); }
.svc__ico--3 { background: linear-gradient(135deg, #7C3AED, #DB2777); }
.svc__head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 12px; }
.svc__title { font-size: 20px; }
.svc__desc { font-size: 15px; color: var(--ink-2); line-height: 1.8; }
.svc__list { margin-top: 20px; padding-top: 20px; border-top: 1px dashed var(--line); display: grid; gap: 10px; }
.svc__list li { display: flex; gap: 10px; font-size: 14.5px; color: var(--ink-2); }
.svc__list svg { color: var(--brand); flex-shrink: 0; margin-top: 6px; }
.svc__foot { margin-top: 24px; font-size: 13px; color: var(--ink-3); }

/* ------------------------------------------------------------
 * 09 案例（核心模块）
 * ---------------------------------------------------------- */
.cases { background: var(--surface); }

.case-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}
.tabs {
  display: inline-flex;
  gap: 4px;
  padding: 5px;
  border-radius: var(--r-full);
  background: var(--line-soft);
  border: 1px solid var(--line);
}
.tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 40px;
  padding: 0 20px;
  border-radius: var(--r-full);
  font-size: 14.5px;
  font-weight: 700;
  color: var(--ink-2);
  transition: all var(--t) var(--ease);
}
.tab:hover { color: var(--brand); }
.tab.is-active {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 8px 20px -8px var(--brand-glow);
}
.tab__n {
  font-size: 12px;
  padding: 1px 7px;
  border-radius: var(--r-full);
  background: rgba(15, 23, 42, .08);
}
.tab.is-active .tab__n { background: rgba(255, 255, 255, .22); }

.case-count { font-size: 13.5px; color: var(--ink-3); }
.case-count b { color: var(--ink); font-size: 15px; }

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.case {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  cursor: pointer;
  transition: transform var(--t) var(--ease),
              box-shadow var(--t) var(--ease),
              border-color var(--t) var(--ease);
  animation: cardIn .5s var(--ease-out) both;
  animation-delay: var(--d, 0ms);
}
@keyframes cardIn {
  from { opacity: 0; transform: translateY(18px) scale(.985); }
}
.case:hover {
  transform: translateY(-8px);
  box-shadow: var(--sh-4);
  border-color: var(--brand-100);
}
.case.is-hidden { display: none; }

.case__media {
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  background: #0B1220;
  display: grid;
  place-items: center;
  padding: 14px;
}
.case__media > .mk,
.case__media > .mk-phones,
.case__media > .shot {
  width: 100%;
  transition: transform .5s var(--ease);
}
.case:hover .case__media > .mk,
.case:hover .case__media > .mk-phones,
.case:hover .case__media > .shot { transform: scale(1.04); }
.case__media[data-kind="mini"] > .mk-phones { height: 100%; }

.case__badge {
  position: absolute;
  top: 12px; left: 12px;
  z-index: 3;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 26px;
  padding: 0 11px;
  border-radius: var(--r-full);
  background: rgba(255, 255, 255, .94);
  color: var(--ink);
  font-size: 11.5px;
  font-weight: 800;
  letter-spacing: .02em;
  box-shadow: var(--sh-2);
  backdrop-filter: blur(6px);
}
.case__badge i { width: 6px; height: 6px; border-radius: 50%; background: var(--brand); font-style: normal; }
.case__badge[data-t="mini"] i { background: var(--ok); }
.case__badge[data-t="admin"] i { background: var(--violet); }

.case__zoom {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: grid;
  place-items: center;
  background: linear-gradient(180deg, rgba(7, 11, 22, .1), rgba(7, 11, 22, .72));
  opacity: 0;
  transition: opacity var(--t) var(--ease);
}
.case:hover .case__zoom { opacity: 1; }
.case__zoom span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 42px;
  padding: 0 22px;
  border-radius: var(--r-full);
  background: #fff;
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(10px);
  transition: transform var(--t) var(--ease);
}
.case:hover .case__zoom span { transform: none; }

.case__body { padding: 22px 24px 24px; display: flex; flex-direction: column; flex: 1; }
.case__title { font-size: 17.5px; display: flex; align-items: center; gap: 10px; }
.case__meta { margin-top: 8px; font-size: 12.5px; color: var(--ink-3); display: flex; flex-wrap: wrap; gap: 6px; }
.case__meta i { font-style: normal; }
.case__meta i + i::before { content: "·"; margin-right: 6px; color: var(--line); }
.case__desc {
  margin-top: 14px;
  font-size: 14px;
  color: var(--ink-2);
  line-height: 1.75;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.case__tags { margin-top: 16px; display: flex; flex-wrap: wrap; gap: 7px; }
.case__foot {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line-soft);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  font-weight: 700;
  color: var(--brand);
}
.case__foot small { font-weight: 500; color: var(--ink-3); font-size: 12px; }

/* 空态 */
.case-empty {
  grid-column: 1 / -1;
  text-align: center;
  padding: 80px 0;
  color: var(--ink-3);
}

/* 大图预览 Lightbox */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(7, 11, 22, .92);
  backdrop-filter: blur(6px);
  display: grid;
  place-items: center;
  padding: 40px 24px;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--t) var(--ease), visibility var(--t);
}
.lightbox.is-open { opacity: 1; visibility: visible; }
.lightbox__inner {
  width: min(940px, 100%);
  max-height: 94vh;
  display: flex;
  flex-direction: column;
  background: #0E1526;
  border: 1px solid rgba(148, 163, 184, .22);
  border-radius: var(--r-lg);
  overflow: hidden;
  box-shadow: var(--sh-4);
  transform: translateY(16px) scale(.98);
  transition: transform var(--t) var(--ease);
}
.lightbox.is-open .lightbox__inner { transform: none; }
.lightbox__head {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 22px;
  border-bottom: 1px solid var(--dark-line);
  color: #fff;
}
.lightbox__head h3 { font-size: 18px; }
.lightbox__head p { font-size: 12.5px; color: var(--dark-sub); margin-top: 3px; }
.lightbox__close {
  margin-left: auto;
  width: 36px; height: 36px;
  border-radius: var(--r-sm);
  border: 1px solid rgba(148, 163, 184, .26);
  color: #CBD5E1;
  display: grid;
  place-items: center;
  font-size: 18px;
  transition: all var(--t-fast);
}
.lightbox__close:hover { background: rgba(255, 255, 255, .1); color: #fff; }
.lightbox__stage {
  flex: 1;
  min-height: 0;
  overflow: auto;
  padding: 30px;
  background:
    radial-gradient(circle at 50% 0%, rgba(37, 99, 235, .22), transparent 60%),
    #080D18;
  display: grid;
  place-items: center;
}
.lightbox__stage .mk { width: min(760px, 100%); aspect-ratio: 16 / 10; }
.lightbox__stage .mk-phones { height: auto; width: min(680px, 100%); gap: 6%; }
.lightbox__foot {
  flex-shrink: 0;
  padding: 18px 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  border-top: 1px solid var(--dark-line);
}
.lightbox__foot .tag { background: rgba(37, 99, 235, .16); color: #93C5FD; border-color: rgba(96, 165, 250, .3); }
.lightbox__note {
  margin-left: auto;
  font-size: 12px;
  color: var(--dark-sub);
  align-self: center;
}

/* ------------------------------------------------------------
 * 10 企业服务
 * ---------------------------------------------------------- */
.chan {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 30px 26px;
  border-radius: var(--r-lg);
  background: linear-gradient(180deg, rgba(255, 255, 255, .06), rgba(255, 255, 255, .02));
  border: 1px solid var(--dark-line);
  transition: transform var(--t) var(--ease), border-color var(--t), background var(--t);
}
.chan:hover {
  transform: translateY(-6px);
  border-color: rgba(96, 165, 250, .45);
  background: linear-gradient(180deg, rgba(37, 99, 235, .14), rgba(255, 255, 255, .02));
}
.chan__top { display: flex; align-items: center; gap: 12px; }
.chan__ico {
  width: 40px; height: 40px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-size: 19px;
  background: rgba(255, 255, 255, .07);
  border: 1px solid var(--dark-line);
}
.chan__title { font-size: 16.5px; color: #fff; }
.chan__desc { font-size: 13.5px; line-height: 1.8; color: var(--dark-sub); }
.chan__list { display: grid; gap: 8px; margin-top: auto; padding-top: 4px; }
.chan__list li {
  font-size: 13px;
  color: #A9B7CE;
  display: flex;
  gap: 9px;
  align-items: baseline;
}
.chan__list li::before {
  content: "";
  width: 5px; height: 5px;
  border-radius: 50%;
  background: #60A5FA;
  flex-shrink: 0;
  transform: translateY(-2px);
}

/* ------------------------------------------------------------
 * 11 为什么免费 / 商业闭环
 * ---------------------------------------------------------- */
.flow {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  margin-top: 8px;
}
.flow__step {
  position: relative;
  padding: 28px 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-right: 0;
}
.flow__step:first-child { border-radius: var(--r-lg) 0 0 var(--r-lg); }
.flow__step:last-child { border-radius: 0 var(--r-lg) var(--r-lg) 0; border-right: 1px solid var(--line); }
.flow__step b {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  border-radius: 10px;
  background: var(--brand-050);
  color: var(--brand);
  font-size: 14px;
  font-weight: 800;
  margin-bottom: 16px;
}
.flow__step h4 { font-size: 16px; margin-bottom: 8px; }
.flow__step p { font-size: 13.5px; color: var(--ink-2); line-height: 1.75; }
.flow__step::after {
  content: "";
  position: absolute;
  right: -7px; top: 44px;
  width: 13px; height: 13px;
  border-radius: 50%;
  background: var(--brand);
  border: 3px solid var(--surface);
  z-index: 2;
}
.flow__step:last-child::after { display: none; }

.explain {
  margin-top: 40px;
  padding: 30px 34px;
  border-radius: var(--r-lg);
  background: linear-gradient(120deg, var(--brand-050), #F5F3FF);
  border: 1px solid var(--brand-100);
  display: flex;
  gap: 20px;
  align-items: flex-start;
}
.explain__ico {
  width: 44px; height: 44px;
  border-radius: 12px;
  background: var(--brand);
  color: #fff;
  display: grid;
  place-items: center;
  flex-shrink: 0;
  font-size: 20px;
}
.explain h4 { font-size: 17px; margin-bottom: 10px; }
.explain p { font-size: 14.5px; color: var(--ink-2); line-height: 1.85; }
.explain p + p { margin-top: 10px; }

/* ------------------------------------------------------------
 * 12 流程
 * ---------------------------------------------------------- */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: s; }
.step { position: relative; padding-top: 8px; }
.step__n {
  display: inline-grid;
  place-items: center;
  width: 44px; height: 44px;
  border-radius: 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--brand);
  font-weight: 800;
  font-size: 15px;
  margin-bottom: 18px;
  box-shadow: var(--sh-1);
}
.step h4 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--ink-2); line-height: 1.8; }
.step u {
  position: absolute;
  top: 22px; right: 16px;
  font-size: 12px;
  color: var(--ink-3);
  text-decoration: none;
}

/* ------------------------------------------------------------
 * 13 FAQ
 * ---------------------------------------------------------- */
.faq { max-width: 860px; margin: 0 auto; display: grid; gap: 12px; }
.qa {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r);
  overflow: hidden;
  transition: border-color var(--t), box-shadow var(--t);
}
.qa[open] { border-color: var(--brand-100); box-shadow: var(--sh-2); }
.qa summary {
  list-style: none;
  cursor: pointer;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 14px;
}
.qa summary::-webkit-details-marker { display: none; }
.qa summary::after {
  content: "";
  margin-left: auto;
  width: 9px; height: 9px;
  border-right: 2px solid var(--ink-3);
  border-bottom: 2px solid var(--ink-3);
  transform: rotate(45deg) translateY(-2px);
  transition: transform var(--t) var(--ease);
  flex-shrink: 0;
}
.qa[open] summary::after { transform: rotate(-135deg) translateY(-2px); border-color: var(--brand); }
.qa summary em {
  font-style: normal;
  width: 26px; height: 26px;
  border-radius: 8px;
  background: var(--brand-050);
  color: var(--brand);
  font-size: 12px;
  font-weight: 800;
  display: grid;
  place-items: center;
  flex-shrink: 0;
}
.qa__body {
  padding: 0 24px 22px 64px;
  font-size: 14.5px;
  color: var(--ink-2);
  line-height: 1.9;
}

/* ------------------------------------------------------------
 * 14 关于我
 * ---------------------------------------------------------- */
.about { display: grid; grid-template-columns: .82fr 1.18fr; gap: 60px; align-items: center; }
.about__card {
  position: relative;
  padding: 36px 32px;
  border-radius: var(--r-xl);
  background: linear-gradient(160deg, #101827, #0A1020);
  border: 1px solid var(--dark-line);
  color: var(--dark-text);
  overflow: hidden;
}
.about__card::after {
  content: "";
  position: absolute;
  width: 260px; height: 260px;
  right: -90px; top: -90px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(37, 99, 235, .45), transparent 68%);
  filter: blur(18px);
}
.avatar {
  width: 88px; height: 88px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 30px;
  font-weight: 800;
  color: #fff;
  background: linear-gradient(135deg, var(--brand), #7C3AED);
  box-shadow: 0 14px 30px -12px var(--brand-glow);
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
}
.about__name { font-size: 22px; color: #fff; position: relative; z-index: 1; }
.about__role { font-size: 13.5px; color: var(--dark-sub); margin-top: 6px; position: relative; z-index: 1; }
.about__badges { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; position: relative; z-index: 1; }
.about__stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 26px;
  padding-top: 22px;
  border-top: 1px solid var(--dark-line);
  position: relative;
  z-index: 1;
}
.about__stats b { display: block; font-size: 22px; color: #fff; }
.about__stats span { font-size: 12px; color: var(--dark-sub); }

.about__text h3 { font-size: clamp(24px, 3vw, 34px); margin-bottom: 20px; }
.about__text p { font-size: 16px; color: var(--ink-2); line-height: 1.95; }
.about__text p + p { margin-top: 16px; }
.about__text strong { color: var(--ink); font-weight: 700; }
.about__list { margin-top: 26px; display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.about__list li {
  display: flex;
  gap: 10px;
  font-size: 14.5px;
  color: var(--ink-2);
  align-items: flex-start;
}
.about__list svg { color: var(--brand); flex-shrink: 0; margin-top: 5px; }

/* ------------------------------------------------------------
 * 15 转化区
 * ---------------------------------------------------------- */
.cta {
  position: relative;
  background: linear-gradient(140deg, #0B1D48 0%, #10275C 45%, #1E1B4B 100%);
  border-radius: var(--r-xl);
  padding: 60px 56px;
  overflow: hidden;
  color: #fff;
}
.cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(148, 163, 184, .1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 163, 184, .1) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: radial-gradient(ellipse 80% 100% at 100% 0%, #000, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 80% 100% at 100% 0%, #000, transparent 70%);
}
.cta__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.3fr .7fr;
  gap: 48px;
  align-items: center;
}
.cta h2 { font-size: clamp(26px, 3.4vw, 38px); }
.cta__desc { margin-top: 18px; font-size: 16px; color: #C3CFE3; line-height: 1.9; max-width: 560px; }
.cta__list { margin-top: 26px; display: grid; gap: 11px; }
.cta__list li { display: flex; gap: 11px; font-size: 14.5px; color: #D5DEEB; align-items: flex-start; }
.cta__list svg { color: #4ADE80; flex-shrink: 0; margin-top: 5px; }

.qr-box {
  background: rgba(255, 255, 255, .07);
  border: 1px solid rgba(148, 163, 184, .24);
  border-radius: var(--r-lg);
  padding: 24px;
  text-align: center;
  backdrop-filter: blur(10px);
}
.qr {
  width: 148px; height: 148px;
  margin: 0 auto 16px;
  border-radius: var(--r);
  background:
    repeating-conic-gradient(#0F172A 0% 25%, #FFFFFF 0% 50%) 50% / 12px 12px;
  border: 8px solid #fff;
  box-shadow: var(--sh-3);
  position: relative;
}
.qr::after {
  content: "微信二维码";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-size: 11.5px;
  font-weight: 700;
  color: transparent;
  background: rgba(255, 255, 255, .82);
  opacity: 0;
  transition: opacity var(--t);
  border-radius: 6px;
}
.qr-box:hover .qr::after { opacity: 1; }
.qr-box b { display: block; font-size: 15px; }
.qr-box small { display: block; font-size: 12.5px; color: #A9B7CE; margin-top: 6px; line-height: 1.7; }

/* ------------------------------------------------------------
 * 16 页脚
 * ---------------------------------------------------------- */
.footer {
  background: #05080F;
  color: #7E8DA6;
  padding: 64px 0 32px;
  font-size: 13.5px;
}
.footer__grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--dark-line);
}
.footer h4 { color: #E8EEF9; font-size: 14.5px; margin-bottom: 16px; }
.footer li { margin-bottom: 10px; }
.footer a { transition: color var(--t-fast); }
.footer a:hover { color: #93C5FD; }
.footer__brand p { margin-top: 16px; line-height: 1.85; max-width: 320px; }
.footer .logo { color: #fff; }
.footer .logo__sub { color: #7E8DA6; }
.footer__bottom {
  padding-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  align-items: center;
  justify-content: space-between;
}
.footer__beian { display: flex; flex-wrap: wrap; gap: 18px; align-items: center; }
.footer__beian a { display: inline-flex; align-items: center; gap: 8px; }
.footer__beian a:hover { color: #93C5FD; }
.footer__beian svg { opacity: .7; }

/* ------------------------------------------------------------
 * 17 直播模式
 * ---------------------------------------------------------- */
body.live-mode {
  font-size: 18px;
}
body.live-mode .section { padding: 104px 0; }
body.live-mode .h-sec { font-size: clamp(30px, 3.8vw, 46px); }
body.live-mode .sub-sec { font-size: 19px; }
body.live-mode .case__title { font-size: 19px; }
body.live-mode .case__desc { font-size: 15.5px; -webkit-line-clamp: 3; }
body.live-mode .svc__title { font-size: 22px; }
body.live-mode .svc__desc,
body.live-mode .svc__list li { font-size: 16.5px; }
body.live-mode .chan__title { font-size: 18.5px; }
body.live-mode .chan__desc,
body.live-mode .chan__list li { font-size: 15px; }
body.live-mode .qa summary { font-size: 17.5px; }
body.live-mode .qa__body { font-size: 16px; }
body.live-mode .nav__link { font-size: 16px; }
body.live-mode .case__meta { font-size: 14px; }
body.live-mode .tag { font-size: 13px; height: 29px; }
body.live-mode .case__media { padding: 20px; }
body.live-mode .grid-3,
body.live-mode .case-grid { gap: 34px; }

/* 直播引导条 */
.live-hint {
  position: fixed;
  left: 50%;
  bottom: 22px;
  transform: translateX(-50%) translateY(120%);
  z-index: 150;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 10px 12px 10px 20px;
  border-radius: var(--r-full);
  background: rgba(14, 21, 38, .94);
  border: 1px solid rgba(148, 163, 184, .24);
  box-shadow: var(--sh-4);
  color: #fff;
  font-size: 13.5px;
  font-weight: 600;
  backdrop-filter: blur(12px);
  transition: transform .5s var(--ease);
}
.live-hint.is-on { transform: translateX(-50%) translateY(0); }
.live-hint__dot {
  width: 9px; height: 9px;
  border-radius: 50%;
  background: #EF4444;
  animation: pulse 1.6s infinite;
}
.live-hint button {
  height: 32px;
  padding: 0 16px;
  border-radius: var(--r-full);
  background: var(--brand);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
}
.live-hint button:hover { background: var(--brand-600); }

/* 回到顶部 */
.to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 140;
  width: 46px; height: 46px;
  border-radius: 50%;
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--ink-2);
  display: grid;
  place-items: center;
  box-shadow: var(--sh-3);
  opacity: 0;
  visibility: hidden;
  transition: all var(--t) var(--ease);
}
.to-top.is-on { opacity: 1; visibility: visible; }
.to-top:hover { color: var(--brand); border-color: var(--brand); transform: translateY(-3px); }

/* ------------------------------------------------------------
 * 18 自动演示（讲解神器）
 * ---------------------------------------------------------- */
body.is-demo { scroll-behavior: smooth; }
.demo-progress {
  position: fixed;
  left: 0; right: 0; top: 0;
  height: 3px;
  z-index: 200;
  background: transparent;
  opacity: 0;
  transition: opacity var(--t);
}
body.is-demo .demo-progress { opacity: 1; }
.demo-progress i {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--brand), #22D3EE);
  transition: width .3s linear;
}

/* ------------------------------------------------------------
 * 19 响应式
 * ---------------------------------------------------------- */
@media (max-width: 1180px) {
  .nav__menu { gap: 0; }
  .nav__link { padding: 8px 10px; font-size: 14px; }
  /* 收窄导航：去掉品牌副标题，给工具按钮腾位置（按钮文字必须保留，
     否则只剩一个空胶囊，直播时看不出是干什么的） */
  .nav .logo__sub { display: none; }
  .tool-btn { padding: 0 10px; font-size: 12.5px; }
}

@media (max-width: 1024px) {
  :root { --sp-7: 64px; --sp-8: 88px; }
  /* minmax(0, 1fr) 不能写成 1fr：默认的 auto 下限会被子元素的最小内容宽度
     撑开，导致整列比容器还宽、文字在手机上被裁掉 */
  .hero__grid { grid-template-columns: minmax(0, 1fr); gap: 56px; }
  .hero__grid > * { min-width: 0; }
  .hero__visual { max-width: 620px; }
  .tool-btn { padding: 0 9px; font-size: 12px; height: 32px; }
  .float-card--a { left: 0; }
  .float-card--b { right: 0; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .case-grid { grid-template-columns: repeat(2, 1fr); }
  .flow { grid-template-columns: repeat(2, 1fr); }
  .flow__step:nth-child(odd) { border-radius: var(--r-lg) 0 0 0; }
  .flow__step:nth-child(even) { border-radius: 0 var(--r-lg) 0 0; border-right: 1px solid var(--line); }
  .flow__step:nth-child(3) { border-radius: 0 0 0 var(--r-lg); }
  .flow__step:nth-child(4) { border-radius: 0 0 var(--r-lg) 0; }
  .flow__step:nth-child(2)::after { display: none; }
  .flow__step:nth-child(4)::after { display: none; }
  .about { grid-template-columns: 1fr; gap: 40px; }
  .cta { padding: 48px 36px; }
  .cta__inner { grid-template-columns: 1fr; gap: 36px; }
  .footer__grid { grid-template-columns: 1fr 1fr; gap: 32px; }

  /* 导航折叠为汉堡菜单 */
  .burger { display: grid; order: 3; }
  .nav__inner { gap: 14px; }
  .nav__tools { order: 2; margin-left: auto; }
  .nav__actions { display: none; }

  .nav__menu {
    /* 贴住 sticky 导航的下沿。用 top:100% 而不是写死像素值，
       因为顶部公告条在窄屏会换行变高，写死就会漏出一条缝 */
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    margin: 0;
    padding: 14px 18px 22px;
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    box-shadow: var(--sh-3);
    transform: translateY(-14px);
    opacity: 0;
    visibility: hidden;
    transition: all var(--t) var(--ease);
  }
  .nav.is-open .nav__menu { transform: none; opacity: 1; visibility: visible; }
  .nav__link { padding: 14px 12px; font-size: 16px; border-radius: var(--r-sm); }
  .nav__link.is-active { background: var(--brand-050); }
  .nav__link.is-active::after { display: none; }
}

@media (max-width: 860px) {
  .grid-3, .grid-2 { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root { --nav-h: 62px; }
  .wrap { padding: 0 18px; }
  .section { padding: 68px 0; }

  .hero { padding: 56px 0 68px; }
  .hero__stats { gap: 22px; margin-top: 36px; padding-top: 24px; }
  .hero__stat b { font-size: 24px; }
  .win__body { height: 260px; }
  .float-card { display: none; }

  .case-toolbar { flex-direction: column; align-items: stretch; }
  .tabs { overflow-x: auto; justify-content: flex-start; -webkit-overflow-scrolling: touch; }
  .tab { padding: 0 16px; font-size: 14px; flex-shrink: 0; }
  .case-grid { grid-template-columns: 1fr; }
  .case__media { padding: 20px; }

  .flow { grid-template-columns: 1fr; }
  .flow__step, .flow__step:nth-child(n) {
    border-radius: 0;
    border-right: 1px solid var(--line);
    border-bottom: 0;
  }
  .flow__step:first-child { border-radius: var(--r-lg) var(--r-lg) 0 0; }
  .flow__step:last-child { border-radius: 0 0 var(--r-lg) var(--r-lg); border-bottom: 1px solid var(--line); }
  .flow__step::after { display: none; }

  .explain { flex-direction: column; padding: 26px; }
  .steps { grid-template-columns: 1fr; }
  .qa__body { padding-left: 24px; }
  .about__list { grid-template-columns: 1fr; }
  .about__stats { grid-template-columns: 1fr 1fr; }
  .cta { padding: 36px 22px; border-radius: var(--r-lg); }
  .footer__grid { grid-template-columns: 1fr; gap: 28px; }
  .footer__bottom { flex-direction: column; align-items: flex-start; }
  .lightbox__stage { padding: 18px; }
  .to-top { right: 16px; bottom: 16px; }
  .live-hint { left: 14px; right: 14px; bottom: 14px; transform: translateY(140%); }
  .live-hint.is-on { transform: none; }
  .live-hint span.txt { display: none; }
}

/* 打印 */
@media print {
  .nav, .topbar, .live-hint, .to-top { display: none; }
  .section { padding: 24px 0; }
  .reveal { opacity: 1; transform: none; }
}