/* Kotone 官网 — 品牌 VI：琴音蓝 #2455A4 / 深蓝 #122B4F / 金 #E8B93E */
:root{
  --brand:#2455A4; --brand-deep:#122B4F; --brand-light:#4A7BC8;
  --gold:#E8B93E; --green:#34C759;
  --ink:#16181D; --ink-2:#5A6070; --ink-3:#8A90A0;
  --bg:#fff; --bg-soft:#F5F7FB; --line:#E6E9F0;
  --radius:18px; --max:1080px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:"Hiragino Sans","Hiragino Kaku Gothic ProN","Noto Sans JP","PingFang SC",system-ui,-apple-system,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.8;
  font-feature-settings:"palt";
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
.wrap{max-width:var(--max);margin:0 auto;padding:0 24px}

/* ── 导航 ── */
header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.82);
  backdrop-filter:saturate(180%) blur(16px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;gap:28px;height:64px}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;letter-spacing:.2px}
.logo .mark{width:32px;height:32px;border-radius:8px;
  background:linear-gradient(160deg,#2455A4,#16345F);display:flex;align-items:center;
  justify-content:center;gap:2px;padding:0 5px}
.logo .mark i{display:block;width:2.4px;border-radius:2px;background:#fff}
.logo .mark i:nth-child(1){height:6px}.logo .mark i:nth-child(2){height:11px}
.logo .mark i:nth-child(3){height:16px;background:var(--gold)}
.logo .mark i:nth-child(4){height:11px}.logo .mark i:nth-child(5){height:6px}
.nav-links{display:flex;gap:24px;margin-left:auto;font-size:14px;color:var(--ink-2)}
.nav-links a:hover{color:var(--brand)}
.lang{display:flex;gap:2px;background:var(--bg-soft);border-radius:999px;padding:3px}
.lang button{border:0;background:none;font:inherit;font-size:12.5px;padding:5px 11px;
  border-radius:999px;cursor:pointer;color:var(--ink-2)}
.lang button.on{background:#fff;color:var(--brand);font-weight:600;box-shadow:0 1px 3px rgba(0,0,0,.09)}

/* ── Hero ── */
.hero{background:linear-gradient(165deg,#1B3F76 0%,#122B4F 100%);color:#fff;
  padding:90px 0 100px;text-align:center;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;inset:auto -10% -60% -10%;height:60%;
  background:radial-gradient(ellipse at center,rgba(74,123,200,.35),transparent 70%)}
.hero .inner{position:relative;z-index:1}
.hero .mark-lg{width:84px;height:84px;border-radius:20px;margin:0 auto 22px;
  background:linear-gradient(160deg,#2455A4,#16345F);box-shadow:0 14px 44px rgba(0,0,0,.34);
  display:flex;align-items:center;justify-content:center;gap:4px}
.hero .mark-lg i{display:block;width:6px;border-radius:3px;background:#fff}
.hero .mark-lg i:nth-child(1){height:13px}.hero .mark-lg i:nth-child(2){height:23px}
.hero .mark-lg i:nth-child(3){height:33px}
.hero .mark-lg i:nth-child(4){height:42px;background:var(--gold)}
.hero .mark-lg i:nth-child(5){height:33px}
.hero .mark-lg i:nth-child(6){height:23px}.hero .mark-lg i:nth-child(7){height:13px}
.hero h1{font-size:38px;letter-spacing:1px;margin-bottom:6px}
.hero .tagline{font-size:15px;opacity:.82;margin-bottom:34px;letter-spacing:.5px}
.hero .claim{font-size:31px;font-weight:700;line-height:1.55;margin-bottom:20px}
.hero .sub{font-size:15.5px;opacity:.8;max-width:620px;margin:0 auto 34px;line-height:1.9}
.btn{display:inline-block;padding:14px 34px;border-radius:999px;font-weight:600;font-size:15px;
  background:#fff;color:var(--brand-deep);transition:transform .16s ease,box-shadow .16s ease}
.btn:hover{transform:translateY(-1px);box-shadow:0 8px 24px rgba(0,0,0,.22)}
.download-block{display:flex;flex-direction:column;align-items:center;gap:14px}
.download-qr{display:block;padding:10px;background:#fff;border-radius:16px;
  box-shadow:0 14px 38px rgba(0,0,0,.24);transition:transform .16s ease,box-shadow .16s ease}
.download-qr:hover{transform:translateY(-2px);box-shadow:0 18px 44px rgba(0,0,0,.3)}
.download-qr img{width:148px;height:148px}
.download-hint{font-size:12.5px;color:rgba(255,255,255,.68);line-height:1.5}
.hero .note{margin-top:16px;font-size:12.5px;opacity:.6}

/* ── 通用区块 ── */
section{padding:84px 0}
section.soft{background:var(--bg-soft)}
.sec-title{font-size:27px;font-weight:700;text-align:center;margin-bottom:12px;letter-spacing:.3px}
.sec-lead{text-align:center;color:var(--ink-2);font-size:15px;margin-bottom:52px}
.grid{display:grid;gap:20px}
.g3{grid-template-columns:repeat(3,1fr)}
.g2{grid-template-columns:repeat(2,1fr)}

/* 痛点 */
.pain{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px}
.pain .ic{font-size:26px;margin-bottom:12px}
.pain h3{font-size:16px;margin-bottom:8px}
.pain p{font-size:14px;color:var(--ink-2);line-height:1.85}
.pain-close{text-align:center;margin-top:40px;font-size:16px;color:var(--ink);
  max-width:680px;margin-left:auto;margin-right:auto;font-weight:500}

/* 步骤 */
.step{position:relative;padding:30px 26px;background:#fff;border-radius:var(--radius);
  border:1px solid var(--line)}
.step .n{width:34px;height:34px;border-radius:10px;background:var(--brand);color:#fff;
  display:flex;align-items:center;justify-content:center;font-weight:700;font-size:16px;margin-bottom:16px}
.step h3{font-size:17px;margin-bottom:9px}
.step p{font-size:14px;color:var(--ink-2);line-height:1.85}

/* 特点 */
.feat{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px}
.feat .ic{width:42px;height:42px;border-radius:12px;background:rgba(36,85,164,.09);
  color:var(--brand);display:flex;align-items:center;justify-content:center;font-size:20px;margin-bottom:16px}
.feat h3{font-size:17px;margin-bottom:10px;line-height:1.5}
.feat p{font-size:14px;color:var(--ink-2);line-height:1.9}

/* 价格 */
.plans{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;align-items:start}
.plans.single{grid-template-columns:minmax(0,440px);justify-content:center}
.plan{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:30px 26px;position:relative}
.plan.hot{border-color:var(--brand);box-shadow:0 10px 34px rgba(36,85,164,.13)}
.plan .tag{position:absolute;top:-11px;left:26px;background:var(--gold);color:#3A2C00;
  font-size:11.5px;font-weight:700;padding:3px 11px;border-radius:999px}
.plan .name{font-size:19px;font-weight:700;margin-bottom:6px}
.plan .price{font-size:32px;font-weight:700;color:var(--brand);letter-spacing:-.5px}
.plan .price .per{font-size:14px;color:var(--ink-3);font-weight:500}
.plan ul{list-style:none;margin-top:20px;padding-top:18px;border-top:1px solid var(--line)}
.plan li{font-size:14px;color:var(--ink-2);padding:7px 0;display:flex;gap:9px;align-items:baseline}
.plan li b{color:var(--ink);font-weight:600}
.price-all{text-align:center;margin-top:26px;font-size:13.5px;color:var(--ink-2)}
.price-note{text-align:center;margin-top:10px;font-size:12.5px;color:var(--ink-3)}

/* FAQ */
.faq{max-width:760px;margin:0 auto}
.faq details{border-bottom:1px solid var(--line);padding:4px 0}
.faq summary{cursor:pointer;padding:18px 34px 18px 0;font-size:15.5px;font-weight:600;
  position:relative;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:6px;top:16px;font-size:21px;
  color:var(--brand);font-weight:400;transition:transform .2s}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq p{padding:0 20px 20px 0;font-size:14.5px;color:var(--ink-2);line-height:1.95}

/* 隐私 */
.privacy-box{max-width:760px;margin:0 auto;background:#fff;border:1px solid var(--line);
  border-radius:var(--radius);padding:32px}
.privacy-box h3{font-size:18px;margin-bottom:18px}
.privacy-box li{list-style:none;font-size:14.5px;color:var(--ink-2);padding:8px 0 8px 28px;
  position:relative;line-height:1.85}
.privacy-box li::before{content:"✓";position:absolute;left:0;color:var(--green);font-weight:700}
.privacy-box a{color:var(--brand);font-size:14px;font-weight:600;display:inline-block;margin-top:14px}

/* CTA */
.cta{background:linear-gradient(165deg,#1B3F76,#122B4F);color:#fff;text-align:center}
.cta h2{font-size:27px;margin-bottom:10px}
.cta p{opacity:.78;margin-bottom:28px;font-size:15px}

/* 页脚 */
footer{background:#0E2340;color:rgba(255,255,255,.62);padding:52px 0 34px;font-size:13.5px}
.foot-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;margin-bottom:34px}
footer h4{color:#fff;font-size:13px;margin-bottom:14px;font-weight:600;letter-spacing:.5px}
footer a{display:block;padding:5px 0;color:rgba(255,255,255,.62)}
footer a:hover{color:#fff}
.foot-brand .logo{color:#fff;margin-bottom:12px}
.foot-brand p{font-size:13px;line-height:1.8;opacity:.75;max-width:270px}
.foot-bot{border-top:1px solid rgba(255,255,255,.12);padding-top:22px;
  display:flex;justify-content:space-between;font-size:12.5px;opacity:.6;flex-wrap:wrap;gap:10px}

@media(max-width:860px){
  .g3,.g2,.plans,.foot-grid{grid-template-columns:1fr}
  .nav-links{display:none}
  .hero{padding:64px 0 74px}
  .hero h1{font-size:31px}.hero .claim{font-size:24px}
  .sec-title{font-size:23px}
  section{padding:60px 0}
  .br-sp{display:none}
}