@charset "UTF-8";
:root{--bg:#f5fbff;--white:#fff;--soft:#eaf7fc;--tint:#dff5fb;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--navy:#174b78;--title:#173b60;--body:#2d4359;--muted:#687f93;--border:#dcebf3;--shadow:0 14px 45px rgba(20,78,119,.07)}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:90px}body{margin:0;background:var(--bg);color:var(--body);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.8}a{color:inherit;text-decoration:none}a:hover{color:var(--blue)}button{font:inherit;cursor:pointer}img{display:block;max-width:100%;height:auto}h1,h2,h3,p{margin-top:0}h1,h2,h3{color:var(--title);line-height:1.35;letter-spacing:-.02em}h1{font-size:clamp(27px,3.2vw,40px);margin-bottom:22px}h2{font-size:clamp(21px,2.2vw,26px);margin-bottom:14px}h3{font-size:19px;margin-bottom:10px}p{margin-bottom:18px}.container{width:min(1160px,calc(100% - 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img{width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.hero-media{min-height:310px;max-height:360px}.feature-media{min-height:210px;max-height:300px}.card-media{min-height:145px;max-height:180px}.portrait-media{min-height:260px;max-height:380px}.media-placeholder{width:100%;min-height:inherit;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;padding:25px;color:var(--navy);font-size:14px;text-align:center;background:radial-gradient(circle at 70% 25%,#c7eef7,transparent 40%),linear-gradient(135deg,#eaf7fc,#dff5fb)}.placeholder-symbol{width:58px;height:58px;display:grid;place-items:center;border-radius:17px;background:#fff9;color:var(--blue);font-size:26px}.section{padding:36px 0}.section-head{margin-bottom:22px}.section-head h2{margin-bottom:7px}.section-head p{color:var(--muted);margin-bottom:0}.panel{background:#fff;border:1px solid var(--border);border-radius:18px;padding:27px;box-shadow:var(--shadow)}.panel h3:last-child,.panel p:last-child{margin-bottom:0}.grid{display:grid;gap:18px}.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}.topic-card{display:block;padding:25px;background:#fff;border:1px solid var(--border);border-radius:16px;transition:transform .2s,box-shadow .2s}.topic-card:hover{transform:translateY(-3px);box-shadow:var(--shadow)}.topic-card .number{font-size:12px;color:var(--blue);font-weight:800;letter-spacing:.1em}.topic-card h3{margin:14px 0 9px}.topic-card p{font-size:15px;color:var(--muted);margin:0}.topic-card .arrow{display:block;color:var(--blue);font-size:19px;margin-top:17px}.feature-split{display:grid;grid-template-columns:1fr 1fr;gap:32px;align-items:center}.feature-split.reverse .media{order:-1}.content-wrap{padding:52px 0 20px}.page-intro{padding-bottom:28px;border-bottom:1px solid var(--border);margin-bottom:32px}.page-intro 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