/* ===== 基础 & 设计变量 ===== */
:root{
  --primary:#FF8A4C;
  --primary-dark:#F2702E;
  --green:#7FC8A9;
  --green-dark:#3E8E6E;
  --blue:#6FB3E0;
  --blue-dark:#2F6FA3;
  --cream:#FFF6EF;
  --tint:#FFF1E6;
  --ink:#2D2A32;
  --ink-soft:#6B6570;
  --line:#F0E2D6;
  --white:#fff;
  --radius:18px;
  --shadow:0 10px 30px rgba(255,138,76,.12);
  --shadow-sm:0 4px 14px rgba(45,42,50,.08);
  --maxw:1120px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  color:var(--ink);
  background:var(--white);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img,svg{display:block}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.container--narrow{max-width:760px}

/* ===== 按钮 ===== */
.btn{
  display:inline-block;font-weight:700;font-size:15px;
  padding:11px 22px;border-radius:999px;border:2px solid transparent;
  cursor:pointer;transition:transform .15s ease, box-shadow .15s ease, background .15s;
  text-align:center;
}
.btn:hover{transform:translateY(-2px)}
.btn--primary{background:var(--primary);color:#fff;box-shadow:var(--shadow)}
.btn--primary:hover{background:var(--primary-dark)}
.btn--ghost{background:#fff;color:var(--primary-dark);border-color:var(--line)}
.btn--ghost:hover{border-color:var(--primary)}
.btn--light{background:#fff;color:var(--primary-dark)}
.btn--light:hover{background:var(--tint)}
.btn--lg{padding:14px 30px;font-size:16px}
.btn--block{display:block;width:100%}

/* ===== 导航 ===== */
.nav{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.9);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);
}
.nav__inner{display:flex;align-items:center;justify-content:space-between;height:66px}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;font-size:20px;color:var(--ink)}
.brand__logo{display:flex}
.nav__links{display:flex;gap:26px}
.nav__links a{font-weight:600;color:var(--ink-soft);font-size:15px;transition:color .15s}
.nav__links a:hover{color:var(--primary-dark)}
.nav__cta{padding:9px 18px;font-size:14px}
.nav__toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px}
.nav__toggle span{width:24px;height:3px;background:var(--ink);border-radius:3px;transition:.2s}

/* ===== Hero ===== */
.hero{padding:56px 0 30px;background:linear-gradient(180deg,#FFF6EF 0%,#fff 100%)}
.hero__inner{display:grid;grid-template-columns:1.05fr .95fr;gap:40px;align-items:center}
.badge{display:inline-block;background:var(--tint);color:var(--primary-dark);
  font-weight:700;font-size:13px;padding:6px 14px;border-radius:999px;margin-bottom:18px}
.hero__title{font-size:clamp(28px,4.4vw,46px);line-height:1.25;font-weight:800;letter-spacing:-.5px}
.hero__title .hl{color:var(--primary)}
.hero__sub{margin:18px 0 26px;font-size:17px;color:var(--ink-soft);max-width:520px}
.hero__cta{display:flex;gap:14px;flex-wrap:wrap}
.hero__points{list-style:none;margin-top:24px;display:flex;flex-direction:column;gap:8px;color:var(--ink-soft);font-weight:600;font-size:15px}
.hero__art{display:flex;justify-content:center}

/* ===== 数据条 ===== */
.stats{background:var(--primary);color:#fff;padding:30px 0}
.stats__inner{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;text-align:center}
.stat b{display:block;font-size:clamp(26px,3.5vw,38px);font-weight:800}
.stat span{font-size:14px;opacity:.92}

/* ===== 区块通用 ===== */
.section{padding:70px 0}
.section--tint{background:var(--cream)}
.section__title{font-size:clamp(24px,3vw,34px);font-weight:800;text-align:center;margin-bottom:12px}
.section__lead{text-align:center;color:var(--ink-soft);font-size:17px;margin-bottom:40px;max-width:640px;margin-left:auto;margin-right:auto}
.section__note{text-align:center;color:var(--ink-soft);margin-top:26px;font-size:15px}
.section__note strong{color:var(--primary-dark)}

/* ===== 网格 & 卡片 ===== */
.grid{display:grid;gap:22px}
.grid--3{grid-template-columns:repeat(3,1fr)}
.grid--4{grid-template-columns:repeat(4,1fr)}
.card{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 22px;box-shadow:var(--shadow-sm);transition:transform .18s, box-shadow .18s}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.card--soft{background:var(--tint);border-color:transparent}
.card__icon{font-size:34px;margin-bottom:12px}
.card h3{font-size:19px;margin-bottom:8px}
.card p{color:var(--ink-soft);font-size:15px}

/* ===== 流程 ===== */
.steps{display:flex;align-items:stretch;justify-content:center;gap:10px;flex-wrap:wrap}
.step{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px 24px;width:280px;text-align:center;box-shadow:var(--shadow-sm)}
.step__num{width:46px;height:46px;border-radius:50%;background:var(--primary);color:#fff;
  font-weight:800;font-size:22px;display:flex;align-items:center;justify-content:center;margin:0 auto 14px}
.step h3{font-size:20px;margin-bottom:8px}
.step p{color:var(--ink-soft);font-size:15px}
.step__arrow{display:flex;align-items:center;font-size:30px;color:var(--primary);font-weight:800}

/* ===== 演示 ===== */
.demo{margin-top:46px;background:var(--tint);border-radius:var(--radius);padding:30px;text-align:center}
.demo__title{font-size:20px;margin-bottom:6px}
.demo__hint{color:var(--ink-soft);font-size:14px;margin-bottom:20px}
.demo__poem{font-size:24px;font-family:serif;line-height:2.4;letter-spacing:2px}
.blank{display:inline-block;min-width:42px;height:40px;margin:0 2px;vertical-align:middle;
  border:2px dashed var(--primary);border-radius:8px;background:#fff;color:var(--primary-dark);
  font-size:22px;font-family:serif;cursor:pointer;font-weight:700}
.blank.filled{border-style:solid;background:var(--green);color:#fff;border-color:var(--green-dark)}
.demo #demoReset{margin-top:18px}

/* ===== 课文库 pills ===== */
.pill{background:var(--white);border:1px solid var(--line);border-radius:999px;
  padding:14px 18px;text-align:center;font-weight:600;box-shadow:var(--shadow-sm);font-size:15px}

/* ===== 价格 ===== */
.pricing{display:grid;grid-template-columns:repeat(2,minmax(0,320px));gap:24px;justify-content:center}
.plan{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);
  padding:30px 26px;box-shadow:var(--shadow-sm);position:relative;display:flex;flex-direction:column}
.plan--hot{border:2px solid var(--primary);box-shadow:var(--shadow)}
.plan__tag{position:absolute;top:-13px;left:50%;transform:translateX(-50%);
  background:var(--primary);color:#fff;font-size:12px;font-weight:700;padding:5px 14px;border-radius:999px}
.plan h3{font-size:22px;margin-bottom:10px}
.plan__price{font-size:34px;font-weight:800;color:var(--primary-dark);margin-bottom:18px}
.plan__price span{font-size:15px;color:var(--ink-soft);font-weight:600}
.plan ul{list-style:none;display:flex;flex-direction:column;gap:10px;margin-bottom:22px;flex:1}
.plan ul li{font-size:15px;color:var(--ink-soft)}

/* ===== 好评 ===== */
.quote{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);
  padding:24px;box-shadow:var(--shadow-sm)}
.quote p{font-size:16px;margin-bottom:12px}
.quote footer{font-weight:700;color:var(--primary-dark);font-size:14px}

/* ===== FAQ ===== */
.faq{display:flex;flex-direction:column;gap:12px}
.faq details{background:var(--white);border:1px solid var(--line);border-radius:14px;padding:4px 18px;box-shadow:var(--shadow-sm)}
.faq summary{cursor:pointer;font-weight:700;font-size:16px;padding:14px 0;list-style:none;position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:4px;font-size:22px;color:var(--primary);transition:.2s}
.faq details[open] summary::after{content:"−";transform:rotate(180deg)}
.faq details p{padding:0 0 16px;color:var(--ink-soft);font-size:15px}

/* ===== CTA ===== */
.cta{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;padding:64px 0;text-align:center}
.cta h2{font-size:clamp(24px,3vw,34px);margin-bottom:10px}
.cta p{opacity:.95;font-size:17px;margin-bottom:26px}
.cta__btns{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.cta__note{margin-top:22px;font-size:14px;opacity:.9}
.cta__note a{text-decoration:underline;font-weight:700}

/* ===== 页脚 ===== */
.footer{background:#2D2A32;color:#cfc9d2;padding:50px 0 24px}
.footer__inner{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:30px}
.footer__brand .brand__name{color:#fff;font-size:22px;font-weight:800}
.footer__brand p{margin-top:8px;font-size:14px;color:#a9a3ad}
.footer__col h4{color:#fff;font-size:15px;margin-bottom:12px}
.footer__col a{display:block;font-size:14px;color:#cfc9d2;margin-bottom:8px;transition:color .15s}
.footer__col a:hover{color:var(--primary)}
.footer__bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;
  margin-top:34px;padding-top:18px;border-top:1px solid #423e48;font-size:13px;color:#8d8794}

/* 联系我们 悬停提示 */
.contact-wrap{position:relative;display:inline-block}
.contact-tip{
  position:absolute;
  bottom:160%;
  left:50%;
  transform:translateX(-50%) translateY(6px);
  width:240px;
  background:#fff;
  color:#2D2A32;
  padding:12px 14px;
  border-radius:12px;
  font-size:13px;
  line-height:1.65;
  box-shadow:0 10px 30px rgba(0,0,0,.22);
  border:1px solid rgba(0,0,0,.06);
  opacity:0;
  visibility:hidden;
  transition:opacity .18s ease,transform .18s ease,visibility .18s;
  z-index:60;
  text-align:left;
  pointer-events:none;
}
.contact-tip::after{
  content:"";
  position:absolute;
  top:100%;
  left:50%;
  transform:translateX(-50%);
  border:8px solid transparent;
  border-top-color:#fff;
}
.contact-wrap:hover .contact-tip,
.contact-wrap:focus-within .contact-tip{
  opacity:1;
  visibility:visible;
  transform:translateX(-50%) translateY(0);
}
.contact-tip .tip-row{display:block}
.contact-tip .tip-row + .tip-row{margin-top:6px}
.contact-tip b{color:var(--primary-dark);font-weight:700}

/* ===== 响应式 ===== */
@media (max-width:900px){
  .hero__inner{grid-template-columns:1fr;text-align:center}
  .hero__sub{margin-left:auto;margin-right:auto}
  .hero__cta,.hero__points{justify-content:center;align-items:center}
  .hero__art{order:-1;max-width:340px;margin:0 auto}
  .grid--3{grid-template-columns:1fr 1fr}
  .grid--4{grid-template-columns:1fr 1fr}
  .steps{flex-direction:column;align-items:center}
  .step__arrow{transform:rotate(90deg)}
  .footer__inner{grid-template-columns:1fr 1fr}
}
@media (max-width:640px){
  .nav__links{position:fixed;top:66px;left:0;right:0;background:#fff;flex-direction:column;
    gap:0;padding:10px 0;border-bottom:1px solid var(--line);
    transform:translateY(-120%);transition:transform .25s;box-shadow:var(--shadow-sm)}
  .nav__links.open{transform:translateY(0)}
  .nav__links a{padding:13px 24px;font-size:16px;border-bottom:1px solid var(--line)}
  .nav__cta{display:none}
  .nav__toggle{display:flex}
  .stats__inner{grid-template-columns:1fr 1fr;gap:24px 12px}
  .grid--3,.grid--4{grid-template-columns:1fr}
  .pricing{grid-template-columns:1fr}
  .footer__inner{grid-template-columns:1fr 1fr}
  .footer__bottom{flex-direction:column}
}