:root{--navy:#123b63;--blue:#2f80c1;--blue-soft:#eaf4fb;--gold:#c89b3c;--ink:#172b3f;--muted:#657789;--line:#dbe5ed;--bg:#f3f7fa;--white:#fff;--green:#198754;--red:#bd3d42;--shadow:0 14px 34px rgba(25,60,90,.09);font-family:"Microsoft YaHei","PingFang SC",system-ui,sans-serif;color:var(--ink);background:var(--bg)}*{box-sizing:border-box}body{margin:0;min-height:100vh;background:radial-gradient(circle at 85% 0,#dfedf7 0,transparent 28%),var(--bg)}a{color:var(--navy);text-decoration:none}button,input,select,textarea{font:inherit}.site-header{height:72px;padding:0 max(24px,calc((100vw - 1240px)/2));display:flex;align-items:center;gap:32px;background:rgba(255,255,255,.94);border-bottom:1px solid 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.narrow-panel{max-width:620px;margin:50px auto}.stacked-form{display:grid;gap:9px}.stacked-form label{font-weight:700;font-size:13px;margin-top:8px}.stacked-form input{width:100%;border:1px solid #cfdce6;border-radius:10px;padding:11px 13px}.stacked-form small,.stacked-form li{color:var(--muted);font-size:12px;line-height:1.6}.stacked-form ul{margin:0;padding-left:20px}.errorlist{color:var(--red);font-size:12px}
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@media(max-width:620px){.site-header{padding:0 16px}.brand small,.user-menu>span{display:none}.page-shell{width:min(100% - 20px,1240px);margin-top:16px}.hero{border-radius:17px;align-items:flex-start;flex-direction:column}.score-orb{min-width:90px;height:90px}.lesson-grid{grid-template-columns:1fr}.panel,.question-card{padding:18px;border-radius:15px}.progress-summary{grid-template-columns:1fr auto}.progress-summary>span{display:none}.filter-bar{align-items:stretch;flex-direction:column}.filter-bar select{width:100%}.filter-bar #ranking-updated{margin-left:0}.choice-list.inline{display:grid}.login-intro{display:none}.login-layout{min-height:65vh}.feature-row{flex-wrap:wrap}}

.hero-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap;position:relative;z-index:1}.browser-notebook-link{background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.28);color:#fff}.browser-runner{margin-top:14px;padding:17px;border:1px solid #b9d5e8;border-radius:14px;background:linear-gradient(145deg,#f7fbfe,#eaf4fb)}.browser-runner-heading,.browser-runner-actions{display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}.browser-runner-heading strong,.browser-runner-heading span{display:block}.browser-runner-heading span{font-size:12px;color:var(--muted);margin-top:3px}.client-badge{padding:5px 9px;border-radius:999px;background:#e8f7ef;color:#16724a!important;font-weight:700}.browser-runner p{font-size:13px;line-height:1.65;color:#526b7d;margin:12px 0}.browser-runner-status{font-size:13px;color:var(--muted)}.browser-runner-status.running{color:var(--blue);font-weight:700}.browser-runner-status.passed{color:var(--green);font-weight:700}.browser-runner-status.failed{color:var(--red);font-weight:700}.browser-runner-output{margin-top:13px;display:grid;gap:8px}.browser-case{padding:11px 13px;border-radius:10px;background:#fff;border-left:4px solid var(--green);font-size:13px}.browser-case.failed{border-color:var(--red)}.browser-case b,.browser-case span{display:block}.browser-case pre{margin:7px 0 0;padding:9px;border-radius:8px;background:#10283c;color:#e9f3f9;white-space:pre-wrap;overflow:auto;font:12px/1.55 Consolas,monospace}@media(max-width:620px){.hero-actions{width:100%}.hero-actions .button{width:100%}.browser-runner-actions{align-items:stretch;flex-direction:column}.browser-run-button{width:100%}}