@charset "UTF-8";
:root{--ink:#233e5b;--muted:#647b91;--blue:#246bd2;--line:#e0e7ed;--paper:#fffefa;--shadow:0 7px 22px #24486b08;font-family:"Microsoft YaHei","PingFang SC",Arial,sans-serif;color:var(--ink);background:#f7f8f7;font-synthesis:none}
*{box-sizing:border-box}body{margin:0}h1,h2,h3,p{margin:0}p{line-height:1.85}a{text-decoration:none;color:inherit}button,input{font:inherit}button{color:inherit;cursor:pointer;border:0;background:none}button:disabled{cursor:default;opacity:.45}button,a{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,input:focus-visible,[tabindex="0"]:focus-visible{outline:3px solid #dc9a16;outline-offset:4px}code,pre,kbd{font-family:Consolas,"Cascadia Code",monospace}pre{margin:0;white-space:pre-wrap;overflow-wrap:anywhere;line-height:1.9}code{overflow-wrap:anywhere}img{object-fit:contain}mark{background:#ffe79c;color:inherit;border-radius:6px;padding:2px 5px}.skip{position:fixed;top:-80px;left:200px;padding:14px;background:white;z-index:99}.skip:focus{top:10px}.sidebar{position:fixed;inset:0 auto 0 0;width:190px;padding:25px 16px;background:#fff;border-right:1px solid var(--line);display:flex;flex-direction:column;z-index:20}.brand img{width:157px;height:58px;display:block}.product-name{font-size:13px;font-weight:700;margin:14px 0 35px}.product-name span{font-size:10px;background:#eef3f9;padding:3px 5px;border-radius:5px;color:#718399;margin-left:2px}.nav-caption{font-size:12px;color:#8193a4;margin:0 10px 14px}.sidebar nav{display:grid;gap:10px}.sidebar nav a{display:flex;align-items:center;gap:10px;padding:12px 10px;font-size:14px;white-space:nowrap;border-radius:12px;color:#647b91}.sidebar nav a span{font-size:22px;width:23px;text-align:center}.sidebar nav a.active{background:#eaf2ff;color:#2068ce;font-weight:700}.sidebar nav a:hover{background:#f0f5fc}.sidebar-note{margin-top:auto;padding:12px;border-radius:18px;background:#f6f9ff;text-align:center}.sidebar-note img{width:116px;height:110px;display:block;margin:0 auto}.sidebar-note strong{display:block;font-size:13px;line-height:1.8}.sidebar-note p{font-size:12px;color:var(--muted);margin-top:6px}.sidebar-bottom{font-size:10px;text-align:center;color:#8293a4;margin-top:20px}.workspace{margin-left:190px}.topbar{height:70px;padding:0 34px;display:flex;gap:18px;align-items:center;border-bottom:1px solid var(--line);background:#ffffffb8}.crumb{font-size:13px;color:#91a0ad}.crumb b{font-weight:400;color:#5f778e;margin-left:8px}.search-shortcut{margin-left:auto;border:1px solid var(--line);padding:9px 14px;border-radius:12px;display:flex;gap:10px;align-items:center;font-size:13px;color:#7890a6}.search-shortcut kbd{margin-left:32px;padding:1px 5px;background:#f5f7fa;border-radius:4px}.avatar{background:#ffecad;border:3px solid white;border-radius:50%;width:36px;height:36px;display:grid;place-items:center;font-size:14px;color:#8b6613}main{width:100%;max-width:1230px;margin:0 auto;padding:28px 34px 42px;min-height:calc(100vh - 132px)}main:focus{outline:none}footer{max-width:1230px;margin:auto;border-top:1px solid var(--line);padding:20px 34px;display:flex;justify-content:space-between;gap:20px;font-size:11px;color:#8494a3}.eyebrow{font-size:13px;font-weight:700;color:#5882ab;letter-spacing:1px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:12px;min-height:46px;padding:12px 21px;border-radius:13px;border:1px solid transparent;background:var(--blue);color:white;font-size:16px;font-weight:700;box-shadow:0 4px 0 #1b55a9;transition:transform .16s}.btn:hover:not(:disabled){transform:translateY(-2px)}.btn.secondary{background:white;border-color:#d3dfec;color:#546d87;box-shadow:0 3px 0 #e4eaf1}.btn.small{font-size:15px;padding:10px 17px;min-height:42px}.quiet-link{font-size:14px;color:#3b73ae;white-space:nowrap}.quiet-link:hover{text-decoration:underline}.blue{--tint:#eaf4ff;--accent:#4d8be4;background:var(--tint)}.yellow{--tint:#fff6d9;--accent:#c49529;background:var(--tint)}.peach{--tint:#fff0e7;--accent:#d38a62;background:var(--tint)}.purple{--tint:#f0edff;--accent:#9178cb;background:var(--tint)}.mint{--tint:#eaf7f0;--accent:#5f9d85;background:var(--tint)}
/* 首页：画幅收紧，星宝成为卡片的主体。 */
.home-hero{position:relative;display:grid;grid-template-columns:1.15fr 1fr;align-items:center;min-height:348px;background:#eaf3ff;border:1px solid #dbe6f0;border-radius:30px;overflow:hidden}.hero-copy{position:relative;z-index:2;padding:31px 0 31px 34px}.hero-copy .eyebrow{display:flex;align-items:center;gap:8px}.hero-copy .eyebrow span{width:7px;height:7px;border-radius:50%;background:#eab12e}.hero-copy h1{font-size:39px;line-height:1.5;letter-spacing:1px;margin:14px 0 12px;font-weight:850}.hand-underline{position:relative;white-space:nowrap;z-index:1}.hand-underline:after{content:"";position:absolute;bottom:3px;left:0;right:7px;height:12px;background:#ffdf7e;border-radius:50% 40% 30% 50%;z-index:-1;transform:rotate(-1deg)}.hero-copy p{font-size:17px;line-height:1.9;color:#58738c}.hero-actions{display:flex;gap:21px;align-items:center;margin-top:23px}.hero-meta{display:flex;align-items:center;gap:10px;font-size:12px;color:#6d859c;margin-top:22px}.hero-meta i{font-style:normal;color:#aebdcb}.hero-scene{position:relative;min-height:335px;display:flex;align-items:center;justify-content:center}.hero-circle{position:absolute;width:290px;height:290px;background:#fff4d5;border:12px solid #ffffff60;border-radius:47% 53% 53% 47%;transform:rotate(-14deg)}.hero-scene>img{position:relative;width:302px;height:302px;z-index:1;filter:drop-shadow(0 10px 9px #708fb922)}.floating-hello{position:absolute;z-index:2;top:15px;left:28px;font:18px Consolas,monospace;padding:12px 17px;background:white;border:1px solid #d8e4f4;border-radius:18px 18px 2px 18px;color:#467cab;transform:rotate(-8deg)}.hero-spark{position:absolute;right:35px;top:51px;font-size:37px;color:#e5b137}.hero-code{position:absolute;bottom:6px;right:16px;z-index:3;background:#fffefa;border:1px solid #dce5ee;box-shadow:0 7px 16px #2e507914;border-radius:14px;padding:13px 20px;transform:rotate(3deg)}.hero-code span{display:block;font-size:11px;color:#8394a3;margin-bottom:5px}.hero-code code{font-size:17px;color:#3c6898}.home-lessons{margin-top:31px}.section-heading{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:18px}.section-heading h2{font-size:23px;line-height:1.5}.section-heading .eyebrow{display:block;font-size:12px;margin-bottom:6px}.course-grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:16px}.course-card{min-width:0;border:1px solid #dfe5e8;border-radius:23px;overflow:hidden;box-shadow:0 4px 0 #dfe6eb85;transition:transform .18s,box-shadow .18s}.course-card:hover{transform:translateY(-6px);box-shadow:0 11px 24px #31527614}.course-art{height:198px;position:relative;padding-top:14px;display:flex;justify-content:center;align-items:center;overflow:hidden}.course-art:before{content:"";position:absolute;width:145px;height:145px;border-radius:50%;background:#ffffff83;top:37px}.course-art img{position:relative;width:184px;height:184px;max-width:100%;transition:transform .2s;z-index:1}.course-card:hover img{transform:rotate(-3deg) scale(1.03)}.course-number{position:absolute;top:14px;left:15px;font-size:25px;font-weight:800;color:var(--accent);opacity:.75}.course-sticker{position:absolute;top:18px;right:12px;z-index:2;font-size:10px;font-weight:700;color:#6e8595;background:#ffffffbd;border:1px solid #fff;padding:3px 7px;border-radius:7px}.course-copy{padding:16px 17px 13px;background:#ffffffcf}.course-copy>code{font-size:13px;color:var(--accent);display:block;white-space:nowrap}.course-copy h3{font-size:18px;line-height:1.55;margin:7px 0 5px;min-height:55px}.course-copy p{font-size:13px;color:#748698;line-height:1.6}.course-entry{margin-top:15px;padding-top:12px;border-top:1px dashed #dce3e8;display:flex;align-items:center;justify-content:space-between;font-size:12px;color:#4f7396}.course-entry b{font-size:21px;line-height:1}.path-note{font-size:13px;color:#7890a5;margin:18px 0 0;line-height:1.8}.path-note span{display:inline-block;background:#edf0f5;color:#607e99;padding:2px 9px;border-radius:6px;margin-right:8px}.home-tools{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:24px}.tool-card{display:flex;align-items:center;gap:12px;border:1px solid var(--line);background:white;padding:18px 16px;border-radius:17px}.tool-card>b{margin-left:auto;color:#8095aa}.tool-icon{width:42px;height:45px;flex-shrink:0;background:#eaf3ff;color:#5e8dc1;border-radius:12px;display:grid;place-items:center;font-size:26px}.yellow-icon{background:#fff2c5;color:#b38b34}.purple-icon{background:#eee8fc;color:#987abf}.tool-card h3{font-size:15px;margin-bottom:4px}.tool-card p{font-size:11px;color:#7c8ea0}
/* 绘本式学习页：一页一件事，大字、完整图解。 */
.learning-main{max-width:1310px}.lesson-topline{display:flex;align-items:center;gap:22px;margin-bottom:21px;font-size:13px;color:#7990a4}.lesson-topline>a{color:#4c7198}.lesson-topline>span{margin:auto}.favorite-button{font-size:14px;color:#a4812b;white-space:nowrap;padding:8px 13px;border:1px solid #eadbb4;border-radius:11px;background:#fffaf0}.lesson-shell{display:grid;grid-template-columns:194px minmax(0,1fr);gap:29px}.lesson-rail{align-self:start;position:sticky;top:20px}.rail-cover{border-radius:24px;padding:8px 10px 15px;text-align:center;border:1px solid #e5e5df}.rail-cover img{width:170px;height:170px;display:block;margin:0 auto}.rail-cover code{font-size:15px;color:#637e99}.lesson-rail h2{font-size:18px;margin:17px 0 9px;line-height:1.7}.lesson-rail>p{font-size:13px;color:#74899b;line-height:1.85}.lesson-rail nav{display:grid;gap:5px;margin-top:18px}.lesson-rail nav a{display:flex;align-items:center;gap:9px;padding:9px 8px;border-radius:10px;font-size:14px;color:#71869a}.lesson-rail nav a[aria-current]{background:#e4edfc;color:#2769c1;font-weight:700}.rail-number{width:25px;height:25px;display:grid;place-items:center;border-radius:8px;background:#fff;font-size:12px}.rail-prereq{border-top:1px dashed #d7e0e8;margin-top:18px;padding-top:17px;font-size:12px;color:#8493a2;line-height:1.8}.rail-prereq b{font-weight:500;font-size:12px}.rail-prereq a{display:block;margin-top:8px;color:#527eab}.rail-prereq p{margin-top:7px}.lesson-content{min-width:0;padding:29px 32px;background:var(--paper);border:1px solid #e5e5db;border-radius:25px;box-shadow:0 5px 0 #e7e8df,0 13px 25px #2e425107;position:relative}.step-heading:focus{outline:none}.step-kicker{font-size:14px;color:#8c9aaa;font-weight:600;letter-spacing:1px}.step-kicker i{font-style:normal;margin:0 9px;color:#b4bdc6}.step-heading h1{font-size:29px;letter-spacing:.4px;line-height:1.65;margin:8px 0 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#d9e1e7;padding-top:22px;margin-top:21px}.check-heading{display:flex;gap:9px;align-items:center;color:#738a9c;font-size:14px}.check-heading>span{font-size:24px;color:#e4b044}.check-heading b{color:#516e87;font-size:15px}.check-heading small{font-size:12px;margin-left:auto;color:#95a1ac}.micro-check h2,.review-question h2{font-size:18px;line-height:1.85;margin:10px 0 15px}.micro-options{display:grid;grid-template-columns:1fr 1fr;gap:11px}.answer-option{width:100%;display:flex;align-items:center;gap:11px;padding:13px 14px;border:1px solid #d5dfeb;border-radius:12px;background:white;text-align:left;font-size:16px;line-height:1.65;overflow-wrap:anywhere}.answer-option>b{flex-shrink:0;width:27px;height:27px;background:#edf2f7;border-radius:8px;display:grid;place-items:center;font-size:13px;color:#70849a}.answer-option:hover{border-color:#8cacd4;background:#f5f9ff}.answer-option.chosen{border-color:#5288ce;background:#eaf3ff}.answer-feedback{font-size:16px;line-height:1.9;padding:12px 16px;background:#eef3f9;border-radius:12px;margin-top:14px}.answer-feedback:empty{display:none}.answer-feedback.correct{color:#377555;background:#eaf5eb}.answer-feedback.incorrect{color:#986c3b;background:#fff2df}.page-turn{margin-top:27px;padding-top:20px;border-top:1px solid #e4e7e4;display:flex;align-items:center;justify-content:space-between;gap:15px}.page-turn>span{font-size:12px;color:#8e9dab}.page-turn .btn{font-size:15px;padding:11px 16px}.code-box,.output-box{border-radius:15px;padding:17px 20px;min-width:0}.code-box{background:#263d55;color:#e8f3ff;box-shadow:inset 0 1px 0 #ffffff0e}.output-box{background:white;border:1px solid #d4e2ed;color:#456b88}.box-label{display:block;margin-bottom:12px;font-size:12px;color:#a8bfd5;letter-spacing:1px}.output-box .box-label{color:#8094a6}.code-box pre,.output-box pre{font-size:20px}.code-output{display:grid;grid-template-columns:1.1fr 25px 1fr;align-items:stretch;gap:10px}.between-arrow{align-self:center;font-size:25px;color:#87a5c3}.visual-controls{display:flex;justify-content:center;gap:12px;flex-wrap:wrap;margin:3px 0 19px}.toggle{border:1px solid #ccdceb;background:white;color:#607d95;border-radius:12px;padding:10px 16px;font-size:16px;min-height:45px}.toggle.selected{color:#2160b2;border-color:#85ace2;background:#e8f2ff;box-shadow:0 3px 0 #cbddf5}.explain-strip{padding:15px 18px;font-size:17px;line-height:1.85;border-radius:12px;background:#ffffffbf;border:1px solid #e1e9ee;margin-top:18px;color:#536f88}.explain-strip p{font-size:17px;margin-top:5px}.visual-caption{font-size:17px;color:#667f95;text-align:center;margin-top:15px}svg{display:block;width:100%;height:auto;overflow:visible}.svg-code{font:27px Consolas,monospace;fill:#254b73}.svg-number{font-size:48px;fill:#8e6d24;font-weight:800}.svg-label{font-size:22px;fill:#365975}.svg-caption{font-size:19px;fill:#6a8298}.svg-scroll{overflow-x:auto;overscroll-behavior-x:contain}.good{color:#378560}.bad{color:#b17858}.greeting-scene{display:grid;grid-template-columns:170px 1fr;align-items:center;gap:14px}.greeting-scene>img{width:175px;height:180px}.speech{font-size:30px;padding:20px;background:white;border:2px solid #b8d6f3;border-radius:24px 24px 24px 3px;text-align:center;margin-bottom:15px}.result-ribbon{display:flex;align-items:center;gap:14px;font-size:13px;border-top:1px dashed #cfddea;padding-top:17px;margin-top:17px;color:#6c8497}.result-ribbon strong{font-size:21px;color:#3b688e}.result-ribbon span{margin-left:auto;font-size:12px}.anatomy-code{display:flex;justify-content:center;align-items:center;padding:30px 0;gap:5px}.anatomy-code button{font:32px Consolas,monospace;background:#fff;padding:13px 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span{display:block;flex-basis:100%}.symbol-board{display:grid;gap:12px}.symbol-row{display:flex;align-items:center;justify-content:space-between;gap:10px;background:#ffffffcf;padding:15px;border-radius:15px;flex-wrap:wrap}.symbol-state{font-size:16px;font-weight:700}.symbol-row kbd{padding:8px 12px;border:1px solid #dbe3ea;background:white;border-bottom:3px solid #d6e0e7;border-radius:9px;font-size:25px;min-width:60px;text-align:center}.symbol-row>span:last-child{font-size:13px;color:#8293a0}.punctuation-example{text-align:center;padding:23px 0 2px}.punctuation-example code{font-size:29px}.punctuation-example code span{color:#287bd4}.punctuation-example p{font-size:16px;color:#647e95;margin-top:13px}.quote-inside{text-align:center}.inner-quote{color:#277acc;background:#d8eeff;border-radius:4px}.identity-pair{display:grid;grid-template-columns:1fr 1fr;gap:20px}.identity-card{border:1px solid #dde5ed;border-radius:20px;padding:22px 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#dbe5ed;border-radius:14px;padding:18px;display:grid;gap:13px;font-size:16px}.fix-card code{font-size:18px}.fix-card>span{font-size:18px;color:#39765d}.three-expressions{display:grid;gap:13px}.three-expressions>div{display:flex;align-items:center;gap:15px;padding:20px;border-radius:14px;background:white;border:1px solid #e2e7eb;flex-wrap:wrap}.three-expressions span{font-size:15px;color:#7890a2;flex-basis:100%}.three-expressions code{font-size:23px}.three-expressions b{color:#88a0b4;margin-left:auto}.expression-result{background:#f0f7ec;border-radius:9px;padding:5px 13px;color:#578155}.name-value-header{display:flex;gap:18px;align-items:center;padding:10px 2px 22px;font-size:15px;color:#7d8f9e}.name-value-header code{font-size:22px;font-weight:700;color:#496b8e}.update-phases{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:17px}.update-phases span{background:#fff9;border:1px solid #d8e0e8;border-radius:13px;text-align:center;padding:12px 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