:root{--blue:#315af5;--navy:#172642;--muted:#69758a;--line:#e3e8f3;--canvas:#f7f8fc;--orange:#e8793c;--shadow:0 5px 22px #1b356807}*{box-sizing:border-box}body{margin:0;background:var(--canvas);color:var(--navy);font:15px/1.65 "Microsoft YaHei","PingFang SC",system-ui,sans-serif}button,input,select{font:inherit}button,a,input,select,summary{touch-action:manipulation}button,a{ -webkit-tap-highlight-color:transparent}button{cursor:pointer}a{color:inherit;text-decoration:none}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #9aacff;outline-offset:4px}button:disabled{opacity:.4;cursor:default}button{color:inherit}button,a{transition:background .18s,border-color .18s,box-shadow .18s}.skip{position:fixed;left:16px;top:-60px;background:white;padding:10px;z-index:20}.skip:focus{top:12px}.site-header{height:78px;padding:0 3.5%;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:46px}.brand{display:flex;align-items:center;flex-shrink:0;gap:22px}.brand img{width:174px;height:auto}.brand>span{border-left:1px solid #cbd4e8;padding-left:22px;color:#45536b;font-size:21px;font-weight:400;letter-spacing:2px;white-space:nowrap}.site-header nav{display:flex;gap:30px;height:100%;align-items:center}.site-header nav a{position:relative;font-weight:500;white-space:nowrap}.site-header nav a.active{color:var(--blue)}.site-header nav a.active:after{content:"";height:3px;background:var(--blue);position:absolute;bottom:-24px;left:0;right:0;border-radius:3px}.back{margin-left:auto;color:var(--muted);font-size:13px;white-space:nowrap}.back span{color:var(--blue);margin-left:8px}main{max-width:1512px;margin:auto;padding:25px 38px 0}.breadcrumb{font-size:13px;color:var(--muted);display:flex;gap:15px;margin-bottom:22px}.breadcrumb a:hover{color:var(--blue)}.hero{position:relative;display:flex;min-height:288px;overflow:hidden;background:linear-gradient(110deg,#fff 45%,#eaf0ff);border:1px solid #e6eaf4;border-radius:22px;padding:33px 42px;align-items:center}.hero-copy{position:relative;z-index:1;width:78%}.eyebrow{font-size:12px;font-weight:500;color:var(--blue);letter-spacing:1px}h1{font-size:38px;line-height:1.4;letter-spacing:1px;margin:12px 0 13px;font-weight:650}h1 em{font-style:normal;color:var(--blue)}.hero p{max-width:650px;margin:0;color:var(--muted);font-size:15px}.hero-actions{display:flex;align-items:center;gap:14px;margin:23px 0 18px}.primary,.secondary{display:inline-flex;gap:18px;align-items:center;justify-content:center;min-height:42px;border-radius:9px;padding:9px 18px;white-space:nowrap}.primary{background:var(--blue);color:#fff;border:1px solid var(--blue);box-shadow:0 4px 9px #315af514}.primary:hover{background:#2349dd}.secondary{background:#fff;border:1px solid #d1d9eb;color:var(--navy)}.secondary:hover{background:#eef2ff;border-color:#acbaf5}.text-link{font-size:13px;color:var(--blue);border:0;background:none;padding:7px 0;cursor:pointer}.hero-tags{display:flex;gap:18px;color:#7b8597;font-size:12px}.hero-tags span+span:before{content:"·";margin-right:18px}.hero-art{position:absolute;right:10px;top:0;height:100%;width:260px;overflow:hidden}.hero-art>img{position:absolute;right:23px;width:205px;top:14px;mix-blend-mode:multiply}.art-orbit{width:230px;height:230px;border-radius:50%;background:#dde6ff;position:absolute;top:37px;right:15px}.art-note{position:absolute;right:0;bottom:27px;border:1px solid #ffffffdb;border-radius:13px;background:#fffffff2;padding:12px 18px;color:#ac582a;font-size:13px;transform:rotate(-3deg);box-shadow:0 5px 20px #1726420a}.art-note strong{font-weight:600}.quick-paths{display:flex;gap:10px;align-items:center;margin:20px 0 26px;flex-wrap:wrap}.quick-label{font-size:12px;color:var(--muted);margin-right:7px}.quick-paths button{border:1px solid var(--line);border-radius:30px;padding:7px 15px;background:white;font-size:13px}.quick-paths button span{color:var(--blue);margin-left:8px}.quick-paths button:hover{border-color:#9bacf8}.study-layout{display:grid;grid-template-columns:238px minmax(0,1fr) 205px;gap:20px;align-items:start;scroll-margin-top:22px}.directory,.reader,.coach-card,.mnemonic-card,.reader-tip{background:#fff;border:1px solid var(--line);border-radius:15px;box-shadow:var(--shadow)}.directory{position:sticky;top:20px;padding:20px 14px 12px;max-height:calc(100vh - 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