@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@400;500;600;700;800&display=swap');
:root{--ink:#19314c;--muted:#708094;--blue:#235fb1;--line:#e5eaf0;--pale:#f0f5fc;--white:#fff}*{box-sizing:border-box}body{margin:0;background:#fafbfd;color:var(--ink);font-family:'Noto Sans SC','Microsoft YaHei',sans-serif;font-size:14px}button,input,select{font:inherit}button,a,select{-webkit-tap-highlight-color:transparent}button{cursor:pointer}a{color:inherit;text-decoration:none}button{color:inherit}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #90b5e9;outline-offset:4px}header{height:92px;background:#fff;border-bottom:1px solid var(--line);padding:0 max(32px,calc((100vw - 1240px)/2));display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:12px;font-weight:700;font-size:19px;white-space:nowrap}.logo{background:#1f4775;color:white;width:44px;height:46px;display:grid;place-content:center;position:relative;border-radius:11px 11px 11px 2px;font-family:Georgia,serif;font-size:30px}.logo span{font-size:15px;position:absolute;right:7px;bottom:8px}.brand small{display:block;font-size:9px;letter-spacing:2px;font-weight:500;color:#8492a3;margin-top:5px}nav{display:flex;gap:32px;height:100%;align-items:center}.nav{height:100%;border:0;background:transparent;font-size:14px;position:relative;color:#6d7b8b}.nav.active{color:var(--blue);font-weight:600}.nav.active:after{position:absolute;content:'';bottom:0;left:20%;width:60%;height:3px;background:var(--blue)}.saved{border:1px solid var(--line);background:white;border-radius:7px;padding:10px 14px;font-size:13px}.saved b{margin-left:7px;color:var(--blue);font-size:11px}main{max-width:1240px;margin:auto}.hero{position:relative;padding:64px 52px 44px;margin-top:30px;display:grid;grid-template-columns:1.4fr 1fr;gap:24px;background:linear-gradient(115deg,#f0f5fc,#edf4fa 60%,#e6effa);border-radius:16px;overflow:hidden}.eyebrow{font-size:11px;letter-spacing:2px;color:#51779f;display:flex;align-items:center;gap:8px;font-weight:500}.eyebrow>span{display:inline-block;width:6px;height:6px;border-radius:50%;background:#638cba}h1{font-size:42px;line-height:1.5;letter-spacing:-1px;margin:18px 0 16px;font-weight:800}h1 span{color:var(--blue)}.hero-copy>p{font-size:14px;line-height:1.9;color:#6c8096;margin-bottom:27px}#search-form{display:flex;align-items:center;background:white;padding:7px 8px 7px 16px;border:1px solid #dbe4ef;box-shadow:0 8px 20px #2b599509;border-radius:9px;position:relative;z-index:1}.search-icon{font-family:Arial;font-size:31px;line-height:1;color:#66809b;margin-right:8px}#search{width:100%;min-width:0;border:0;outline:none;font-size:12px;padding:10px 0;color:var(--ink);background:white}#search-form button{flex-shrink:0;border:0;background:#245cab;color:white;border-radius:6px;padding:12px 16px;font-size:12px}#search-form button span{margin-left:12px}.hot{display:flex;gap:12px;align-items:center;color:#91a0af;font-size:10px;margin-top:16px}.hot button{border:0;background:transparent;color:#71849a;padding:0;font-size:11px}.hero-art{position:relative;min-height:325px;align-self:center;display:grid;place-items:center}.art-grid{position:absolute;inset:0;background-image:radial-gradient(#bdcfe2 1px,transparent 1px);background-size:17px 17px;mask-image:radial-gradient(ellipse,#000 25%,transparent 70%)}.paper{width:270px;height:290px;border-radius:9px;background:white;position:absolute}.paper.back{transform:rotate(10deg) translate(15px,0);background:#ccdaec}.paper.front{transform:rotate(-6deg);box-shadow:0 18px 35px #204b6c13;padding:25px 22px}.paper-top{display:flex;justify-content:space-between;font-size:8px;letter-spacing:1px;color:#92a2b2}.paper-top b{font-family:Georgia;font-size:20px;color:#9fb5d0}.paper-title{font-weight:700;line-height:1.9;font-size:17px;margin:14px 0}.paper i{display:block;height:5px;background:#edf1f6;margin:9px 0;border-radius:2px;width:95%}.paper i.short{width:67%}.citation{margin:18px -10px 15px;background:#eef4fc;border:1px solid #dae6f6;border-radius:5px;padding:12px 8px;display:flex;gap:8px;align-items:center;font-size:10px}.citation b{font-family:Georgia;color:#32649e}.citation em{font-style:normal;margin-left:auto;color:#478c7c}.paper-foot{color:#9aa8b7;font-size:8px;margin-top:15px}.floating{position:absolute;right:-2px;bottom:29px;border:1px solid #e0e9f3;background:white;border-radius:7px;font-size:11px;padding:12px 19px;color:#447766;box-shadow:0 9px 25px #213b5810;transform:rotate(3deg)}.spark{position:absolute;top:0;right:25px;font-size:48px;color:#77a1cd;transform:rotate(10deg)}.stats{display:flex;align-items:center;gap:44px;padding:25px 8px 28px;border-bottom:1px solid var(--line);color:#7d8b9c;font-size:12px}.stats b{color:#435d7a;font-size:14px;margin-right:6px}.stat-note{margin-left:auto;color:#9ca7b5;font-size:10px}.workspace{display:grid;grid-template-columns:220px 1fr;gap:36px;padding:34px 0 50px}.aside-label{font-size:11px;color:#8a97a6;margin:6px 0 14px 13px;letter-spacing:1px}.cat{width:100%;display:flex;align-items:center;gap:11px;border:0;background:transparent;padding:13px;border-radius:7px;margin-bottom:5px;text-align:left;font-size:13px;color:#617288}.cat .cat-icon{font-size:17px;width:23px;text-align:center}.cat b{margin-left:auto;font-size:10px;font-weight:400;color:#9aa7b5}.cat.active{background:#e9f0fa;color:#255da2;font-weight:600}.cat.active b{color:#4977b3}.cat:hover{background:#eff3f8}.side-note{border:1px solid var(--line);border-radius:9px;margin-top:30px;padding:19px;background:white}.side-note>span{color:#7f9ec1;font-size:23px}.side-note h3{font-size:13px;margin:9px 0}.side-note p{font-size:11px;line-height:1.9;color:#8492a2}.side-note button{border:0;background:transparent;padding:8px 0 0;font-size:11px;color:#376ba8}.section-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:22px}.small{font-size:9px;letter-spacing:1.6px;color:#8c9eb3}h2{font-size:23px;margin:8px 0;font-weight:700}.section-head p{font-size:12px;color:#8a98a8;margin:8px 0 0}.system-label{display:flex;align-items:center;font-size:10px;color:#8e9bab;gap:9px;flex-shrink:0}select{padding:8px;border:1px solid var(--line);border-radius:6px;background:white;color:#596f89;font-size:11px}#list{display:grid;grid-template-columns:1fr 1fr;gap:14px}.question-card{background:white;border:1px solid var(--line);border-radius:9px;padding:20px 21px;transition:transform .15s,border-color .15s;position:relative;min-height:180px;display:flex;flex-direction:column}.question-card:hover{transform:translateY(-2px);border-color:#b9cde5}.card-top{display:flex;align-items:center;gap:8px;margin-bottom:13px}.tag{font-size:10px;color:#5e80aa;background:#eff4fb;border-radius:4px;padding:4px 7px}.platform{font-size:9px;color:#9aa6b3}.bookmark{margin-left:auto;background:transparent;border:0;color:#98a9bd;font-size:18px;padding:0 3px}.bookmark.on{color:#c18a27}.question-card h3{font-size:14px;margin:0 0 9px;font-weight:600;line-height:1.7}.open-answer{border:0;background:transparent;padding:0;text-align:left;font:inherit;color:inherit}.question-card p{font-size:11px;line-height:1.8;color:#8491a2;margin:0 0 18px}.card-foot{display:flex;justify-content:space-between;align-items:center;margin-top:auto;font-size:9px;color:#9aa6b5}.card-foot button{color:#4774ad;background:transparent;border:0;font-size:10px;padding:0}.bottom-note{display:flex;gap:10px;margin-top:24px;color:#8c99aa;align-items:start}.bottom-note>span{border:1px solid #a3b2c4;border-radius:50%;padding:0 5px;font-size:10px;margin-top:3px}.bottom-note p{margin:0;font-size:10px;line-height:1.9}footer{max-width:1240px;margin:auto;border-top:1px solid var(--line);padding:30px 0 36px;display:flex;justify-content:space-between;align-items:center;gap:25px}.footer-brand{font-size:14px}.footer-brand .logo{width:34px;height:36px;font-size:23px;border-radius:8px 8px 8px 2px}.footer-brand .logo span{font-size:11px;bottom:6px;right:5px}.footer-brand small{font-size:9px;letter-spacing:1px}footer p{font-size:10px;line-height:1.9;color:#929eac}footer>a{font-size:11px;color:#788aa1}.other-view{padding:45px 0 65px;min-height:500px}.other-view>p{color:var(--muted);line-height:1.9}.route-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:30px}.route,.resource{padding:25px;border:1px solid var(--line);border-radius:10px;background:white}.route>span{font-family:Georgia;font-size:32px;color:#a9bed8}.route h3{font-size:18px}.route p{font-size:12px;color:#8090a4;line-height:1.9}.route button{display:block;width:100%;text-align:left;background:transparent;border:0;border-top:1px solid var(--line);padding:14px 0;color:#356ba9;font-size:12px}.resource-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-top:25px}.resource small{color:#8fa2ba}.resource h3{font-size:16px}.resource p{font-size:12px;color:#7d8da2;line-height:1.9}.resource a{font-size:12px;color:var(--blue)}dialog{width:min(730px,calc(100vw - 28px));max-height:88vh;border:0;border-radius:14px;padding:0;color:var(--ink);box-shadow:0 20px 80px #12274233}dialog::backdrop{background:#14294077;backdrop-filter:blur(3px)}.dialog-top{position:sticky;top:0;background:#f4f7fc;display:flex;justify-content:space-between;align-items:center;padding:15px 28px;border-bottom:1px solid var(--line);z-index:2;font-size:12px;color:#5979a2}.dialog-top button{border:0;background:white;border-radius:50%;width:30px;height:30px;color:#687e99}#answer-body{padding:25px 32px 35px}#answer-body h2{line-height:1.7;font-size:24px;margin:0 0 12px}.answer-meta{font-size:11px;color:#8b9aad}.answer-intro{background:#edf4fc;border-radius:7px;padding:15px 18px;line-height:1.9;font-size:13px;margin:24px 0}#answer-body h3{font-size:14px;margin-top:25px}#answer-body ol{padding-left:24px}#answer-body li{font-size:13px;line-height:2;margin:11px 0;padding-left:6px}.tip{background:#faf7ee;border-left:3px solid #d7b77c;padding:13px 16px;color:#8a7656;font-size:12px;line-height:1.9}.source-links{display:flex;flex-direction:column;gap:10px}.source-links a{font-size:12px;color:#3b71b6;line-height:1.8}.answer-actions{display:flex;gap:10px;margin-top:27px}.answer-actions button,#reset{border:1px solid #d3dfed;border-radius:6px;background:white;padding:10px 17px;color:#4a709e;font-size:12px}#empty{text-align:center;padding:60px 20px;color:#8b9caf}#empty>span{font-size:45px}#empty h3{color:#516c8c}#empty p{font-size:12px}#toast{position:fixed;bottom:30px;left:50%;transform:translateX(-50%);background:#21446c;color:white;border-radius:8px;padding:12px 22px;opacity:0;pointer-events:none;transition:opacity .2s;font-size:12px;z-index:10}#toast.show{opacity:1}[hidden]{display:none!important}
@media(min-width:1500px){main,footer{max-width:1240px}.hero{margin-top:40px}}@media(max-width:1300px){main,footer{margin-left:32px;margin-right:32px}.hero{padding:42px 36px}.floating{right:-10px}h1{font-size:36px}}@media(max-width:960px){header{padding:0 24px;gap:15px}nav{gap:15px}.hero{grid-template-columns:1fr}.hero-art{display:none}.hero-copy{max-width:690px}.workspace{grid-template-columns:180px 1fr;gap:22px}#list{grid-template-columns:1fr}.stats{gap:25px}.stat-note{display:none}.route-grid{grid-template-columns:1fr}.resource-grid{grid-template-columns:1fr}}@media(max-width:640px){header{height:auto;min-height:100px;flex-wrap:wrap;padding:16px 20px 0;gap:12px}.brand{font-size:16px}.brand .logo{width:36px;height:39px}.brand small{font-size:8px}nav{order:3;width:100%;height:43px;justify-content:space-around}.nav{font-size:12px}.saved{font-size:12px;padding:8px}.saved span{display:none}main,footer{margin-left:16px;margin-right:16px}.hero{margin-top:18px;padding:28px 22px;border-radius:11px}.eyebrow{font-size:9px;letter-spacing:1px}h1{font-size:30px;margin-top:16px}.hero-copy>p{font-size:12px}#search-form{padding:5px 6px 5px 10px}#search{font-size:11px}#search-form button{padding:10px;font-size:11px}#search-form button span{display:none}.hot{gap:10px;font-size:9px}.hot button{font-size:9px}.stats{gap:13px;justify-content:space-between;padding:19px 0;font-size:9px}.stats b{font-size:11px;margin-right:2px}.workspace{display:block;padding-top:22px}.aside-label,.side-note{display:none}#categories{display:flex;overflow-x:auto;gap:8px;padding-bottom:10px}.cat{white-space:nowrap;width:auto;flex-shrink:0;padding:9px 10px;font-size:11px;border:1px solid var(--line);background:white}.cat .cat-icon{display:none}.cat b{font-size:9px}.section-head{margin-top:15px;align-items:flex-end;gap:10px}h2{font-size:19px}.section-head p{font-size:10px}.system-label{flex-direction:column;align-items:end;font-size:9px;gap:4px}.question-card{min-height:170px}.other-view{padding-top:30px}footer{flex-wrap:wrap;padding:24px 0}footer p{font-size:9px}#answer-body{padding:20px}#answer-body h2{font-size:21px}.dialog-top{padding:12px 20px}.answer-actions{flex-wrap:wrap}}