@charset "UTF-8";
:root{--ink:#17243d;--muted:#67738a;--blue:#2b5df5;--pale:#edf2ff;--line:#e4e9f2;--paper:#fff;--background:#f3f5fa;--mono:"Cascadia Code","Consolas",monospace;--sans:"Segoe UI","Microsoft YaHei","PingFang SC",sans-serif}
*{box-sizing:border-box}html{font-size:16px}body{margin:0;background:var(--background);color:var(--ink);font-family:var(--sans);-webkit-font-smoothing:antialiased}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button:disabled{cursor:default;opacity:.32}a{color:inherit;text-decoration:none}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.65;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #73a0ff;outline-offset:4px}p{line-height:1.75}h1,h2,h3,h4,p{margin-top:0}h1,h2,h3,h4{font-weight:650}strong{font-weight:650}code{font-family:var(--mono)}p code,li code,td code{background:var(--pale);color:#2853c7;border-radius:4px;padding:2px 5px;font-size:.9em}button{border:0;background:none;color:inherit}.skip-link{position:fixed;top:-60px;left:20px;z-index:20;background:var(--blue);color:white;padding:12px}.skip-link:focus{top:10px}
.topbar{height:82px;padding:0 34px;display:flex;align-items:center;justify-content:space-between;background:var(--paper);border-bottom:1px solid var(--line);gap:20px}.brand{display:flex;align-items:center;gap:14px}.brand-mark{width:44px;height:44px;background:var(--blue);border-radius:12px;display:flex;align-items:center;justify-content:center;color:white;font:700 26px var(--mono);letter-spacing:-4px;padding-right:4px}.brand-mark span{font-size:15px;letter-spacing:-3px}.brand strong{display:block;font-size:17px;letter-spacing:.3px}.brand-sub{display:block;color:var(--muted);font-size:11px;letter-spacing:1.6px;margin-top:5px}.topbar-tools{display:flex;align-items:center;gap:22px}.view-switch{display:flex;background:var(--background);border-radius:8px;padding:4px}.view-switch button{padding:7px 18px;border-radius:5px;color:var(--muted);font-size:14px}.view-switch button.active{background:white;color:var(--ink);box-shadow:0 1px 5px #182b4710}.icon-btn,.text-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font-size:14px;color:var(--muted);border-radius:6px}.icon-btn{padding:9px}.icon-btn:hover,.text-btn:hover{background:var(--pale);color:var(--blue)}.text-btn{padding:7px 8px}
.workspace{display:grid;grid-template-columns:224px minmax(0,1fr);min-height:calc(100dvh - 82px)}.sidebar{background:white;border-right:1px solid var(--line);padding:38px 20px 24px;display:flex;flex-direction:column;position:sticky;top:0;height:calc(100dvh - 82px)}.sidebar-heading{padding:0 14px 24px}.small-label{font:500 11px var(--mono);letter-spacing:2px;color:var(--blue)}.sidebar-heading h2{font-size:18px;margin:10px 0 0}.chapter-link{display:flex;width:100%;text-align:left;align-items:flex-start;padding:13px 12px;gap:12px;border-radius:8px;margin:3px 0;color:var(--muted);transition:background .15s}.chapter-link:hover{background:var(--background)}.chapter-link.active{color:var(--blue);background:var(--pale)}.chapter-index{font:500 13px var(--mono);padding-top:3px;width:25px;flex-shrink:0}.chapter-name{display:block;font-size:14px;line-height:1.6}.chapter-sub{display:block;font-size:12px;line-height:1.5;opacity:.7;margin-top:3px}.sidebar-bottom{margin-top:auto;border-top:1px solid var(--line);padding:20px 14px 0;display:flex;flex-direction:column;gap:14px;font-size:13px}.sidebar-bottom>span{font-size:11px;color:var(--muted)}.sidebar-bottom a{display:flex;justify-content:space-between;align-items:center;gap:10px}.sidebar-bottom a:hover{color:var(--blue)}.sidebar-bottom svg{width:15px;height:15px}
.main{padding:25px 38px 0;min-width:0;outline:none;height:calc(100dvh - 82px);display:flex;flex-direction:column}.stage-context{display:flex;justify-content:space-between;align-items:center;min-height:34px;margin-bottom:19px;font-size:13px;color:var(--muted)}.stage-context>span{display:flex;align-items:center;gap:9px}.context-dot{width:5px;height:5px;border-radius:50%;background:var(--blue)}#slides{flex:1;min-height:0;position:relative}.slide{background:white;border:1px solid var(--line);box-shadow:0 8px 24px #17243d04;border-radius:12px;min-height:100%;max-height:100%;overflow:auto;position:relative;padding:40px 45px;display:flex;flex-direction:column;animation:enter .26s ease}.slide::after{content:attr(data-number);position:absolute;right:28px;bottom:18px;color:#aab3c5;font:11px var(--mono);letter-spacing:1px}.slide-kicker{display:flex;align-items:center;gap:12px;font:500 11px var(--mono);letter-spacing:1.9px;color:var(--blue);margin-bottom:13px}.slide-kicker i{width:24px;height:1px;background:var(--blue)}.slide-title{font-size:clamp(25px,2.6vw,40px);line-height:1.35;letter-spacing:-.6px;margin:0 0 12px}.slide-deck{font-size:15px;color:var(--muted);line-height:1.7;margin:0 0 26px;max-width:850px}.slide-body{flex:1;min-height:0}.slide-body> :last-child{margin-bottom:0}.slide h3{font-size:20px;line-height:1.45}.two-col{display:grid;grid-template-columns:1fr 1fr;gap:32px;height:100%;align-items:start}.two-col.wide-code{grid-template-columns:1.3fr 1fr;gap:30px}.concept-layout{display:grid;grid-template-columns:1fr 1.08fr;gap:40px;align-items:center;height:100%}.prose p{font-size:clamp(16px,1.35vw,20px);line-height:1.9}.big-definition{font-size:clamp(21px,1.7vw,27px)!important;line-height:1.7!important}.big-definition em{font-style:normal;color:var(--blue);font-weight:650}.bullets{list-style:none;padding:0;margin:20px 0 0}.bullets li{position:relative;padding-left:19px;margin-bottom:14px;line-height:1.75;font-size:16px}.bullets li::before{content:"";position:absolute;left:0;top:.7em;width:5px;height:5px;background:var(--blue);border-radius:1px}.note{background:var(--pale);border-left:3px solid var(--blue);padding:13px 17px;font-size:14px;line-height:1.8;color:#36528b;margin-top:20px}.slide-label{display:block;font-size:12px;font-weight:600;color:var(--muted);margin-bottom:14px;letter-spacing:.7px}.accent{color:var(--blue)}.soft{color:var(--muted)}
.cover{padding:54px 48px 36px;display:flex}.cover .slide-body{display:flex;flex-direction:column}.cover-layout{display:grid;grid-template-columns:1.2fr .8fr;gap:36px;align-items:center;flex:1}.cover-chapter{font:400 12px var(--mono);letter-spacing:2px;color:var(--blue);margin-bottom:22px;display:flex;align-items:center;gap:10px}.cover-chapter::before{content:"";width:25px;height:2px;background:var(--blue)}.cover h1{font-size:clamp(34px,3.85vw,59px);line-height:1.26;letter-spacing:-1.4px;margin:0 0 25px}.cover h1 span{color:var(--blue)}.cover-description{color:var(--muted);font-size:17px;line-height:1.9;max-width:540px}.cover-meta{display:flex;gap:25px;font-size:13px;color:var(--muted);margin-top:28px}.cover-meta strong{color:var(--ink)}.type-visual{background:#132440;border-radius:10px;overflow:hidden;align-self:center;width:100%;border:1px solid #294067}.type-visual-header{border-bottom:1px solid #31415c;padding:13px 20px;display:flex;gap:7px;align-items:center;color:#98aace;font:11px var(--mono)}.type-visual-header>span{margin-left:auto}.editor-dot{width:6px;height:6px;border-radius:50%;background:#577091}.type-visual-main{padding:22px 26px 26px}.type-cpp{font:700 clamp(70px,7.5vw,120px) var(--mono);letter-spacing:-11px;line-height:1.4;color:#f4f7ff;margin:0 0 14px;white-space:nowrap}.type-cpp span{color:#7fa4ff}.mini-code{font:14px/1.85 var(--mono);color:#cad5ef;white-space:pre}.mini-code .comment{color:#9babca}.mini-code .keyword{color:#91aaff}.mini-code .string{color:#a6e3c0}.cover-route{display:flex;margin-top:32px;padding-top:23px;border-top:1px solid var(--line);justify-content:space-between;gap:16px}.route-item{font-size:13px;line-height:1.6}.route-item span{display:block;font:11px var(--mono);color:var(--blue);margin-bottom:5px}
.goal-layout{display:grid;grid-template-columns:.75fr 1.25fr;gap:40px}.goal-summary{border-right:1px solid var(--line);padding-right:32px}.goal-summary .huge{font:500 72px var(--mono);color:var(--blue);letter-spacing:-5px;margin-bottom:5px}.goal-summary h3{font-size:27px;line-height:1.5}.goal-summary p{font-size:15px;line-height:1.9;color:var(--muted)}.goal-list{display:grid;gap:16px}.goal-row{display:grid;grid-template-columns:40px 1fr;gap:14px;align-items:start}.goal-row>span{font:12px var(--mono);color:var(--blue);padding-top:4px}.goal-row h3{font-size:17px;margin:0 0 3px}.goal-row p{font-size:14px;color:var(--muted);margin:0;line-height:1.65}.comparison-col{border-top:2px solid var(--ink);padding-top:19px}.comparison-col:last-child{border-color:var(--blue)}.comparison-col h3{font-size:25px;margin:4px 0 7px}.comparison-col p{color:var(--muted);font-size:15px}.comparison-caption{display:flex;align-items:center;gap:12px;margin-top:18px;font-size:14px}.comparison-caption span{font:12px var(--mono);background:var(--pale);padding:4px 8px;color:var(--blue)}
.code-panel{background:#14223a;border-radius:8px;border:1px solid #233452;overflow:hidden;min-width:0;color:#dce5f9}.code-header{display:flex;align-items:center;justify-content:space-between;padding:11px 17px;background:#1c2c46;border-bottom:1px solid #304059;font:12px var(--mono);color:#a6b5d1}.copy-btn{color:#b3c3e1;display:flex;align-items:center;gap:5px;font:12px var(--sans);padding:2px 4px;border-radius:3px}.copy-btn:hover{background:#334569;color:white}.copy-btn svg{width:14px;height:14px}.code-panel pre{margin:0;padding:17px 20px;overflow:auto;font:14px/1.85 var(--mono);tab-size:4;white-space:pre;max-height:53vh}.code-line{display:block;min-height:1.85em}.line-number{display:inline-block;width:2em;margin-right:1.1em;text-align:right;color:#637796;user-select:none;font-size:.85em}.code-keyword{color:#a5b7ff}.code-string{color:#a8e0c2}.code-comment{color:#8b9fbe}.code-number{color:#ffc995}.code-directive{color:#87cffa}.output{border:1px solid var(--line);border-radius:6px;margin-top:16px;background:#f6f8fc;padding:13px 16px;min-width:0}.output>span{display:block;color:var(--muted);font-size:12px;margin-bottom:8px}.output pre{margin:0;font:13px/1.8 var(--mono);white-space:pre-wrap;overflow-wrap:anywhere}.point-list{counter-reset:point;list-style:none;padding:0;margin:0}.point-list li{counter-increment:point;display:grid;grid-template-columns:25px 1fr;gap:11px;margin-bottom:18px;font-size:15px;line-height:1.8}.point-list li::before{content:counter(point,decimal-leading-zero);font:11px var(--mono);padding-top:5px;color:var(--blue)}.point-list li strong{display:block}.point-list li span{color:var(--muted);font-size:14px}
.present-footer{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:15px 0 14px;min-height:75px}.keyboard-tip{display:flex;gap:6px;align-items:center;color:#7a859a;font-size:12px}kbd{font:10px var(--mono);border:1px solid #dce2ee;min-width:20px;height:20px;display:inline-flex;align-items:center;justify-content:center;border-radius:4px;background:#fff;color:#6c7890}.tip-divider{height:12px;width:1px;background:#d8deea;margin:0 8px}.page-controls{display:flex;align-items:center;gap:16px}.nav-btn{width:34px;height:34px;background:white;border:1px solid var(--line);border-radius:7px;display:flex;align-items:center;justify-content:center}.nav-btn:not(:disabled):hover{border-color:var(--blue);color:var(--blue)}.nav-btn.next{background:var(--blue);border-color:var(--blue);color:white}.nav-btn.next:not(:disabled):hover{background:#1549dd;color:white}.page-count{display:flex;align-items:center;gap:10px;font:13px var(--mono);color:var(--muted)}.page-count strong{color:var(--ink);font-size:16px;font-weight:500}.progress-track{height:3px;background:#e0e6f1;margin:0 -38px;flex-shrink:0}.progress-track div{height:100%;background:var(--blue);transition:width .25s}
dialog{border:1px solid var(--line);border-radius:14px;box-shadow:0 24px 100px #12234235;color:var(--ink);padding:26px;width:min(700px,calc(100vw - 32px));max-height:85dvh}dialog::backdrop{background:#15243b65;backdrop-filter:blur(3px)}.dialog-heading{display:flex;align-items:center;justify-content:space-between;gap:15px;margin-bottom:23px}.dialog-heading h2{font-size:22px;margin:6px 0 0}#outline-list{display:grid;grid-template-columns:1fr 1fr;gap:7px}.outline-item{border:1px solid var(--line);border-radius:6px;display:flex;align-items:center;gap:12px;text-align:left;padding:12px;font-size:14px;line-height:1.5}.outline-item>span{font:12px var(--mono);color:var(--muted)}.outline-item:hover,.outline-item.active{border-color:#a5baff;background:var(--pale);color:var(--blue)}#notes-content{font-size:17px;line-height:1.95}#notes-content p{margin-bottom:16px}#notes-content .source-tag{font-size:13px;color:var(--muted);border-top:1px solid var(--line);padding-top:15px}#toast{position:fixed;bottom:25px;left:50%;transform:translate(-50%,20px);background:var(--ink);color:white;font-size:14px;padding:10px 18px;border-radius:8px;opacity:0;pointer-events:none;transition:.2s;z-index:20}#toast.visible{opacity:1;transform:translate(-50%,0)}.noscript-note{position:fixed;inset:100px 20px auto;background:white;padding:30px;z-index:10}
.reading .main{height:auto;min-height:calc(100dvh - 82px);padding-bottom:30px}.reading #slides{display:grid;gap:28px}.reading .slide{height:auto;max-height:none;min-height:560px;overflow:visible}.reading .slide-body{min-height:300px}.reading .present-footer,.reading .progress-track{display:none}.reading .stage-context{position:sticky;top:0;z-index:2;background:var(--background);padding:12px 0;margin-top:-12px}.reading .cover{min-height:580px}.reading .code-panel pre{max-height:none}.reading .slide::after{bottom:16px}.reading .read-notes{margin-top:24px;border-top:1px solid var(--line);padding:16px 0 4px;color:var(--muted);font-size:14px;line-height:1.8}.read-notes summary{cursor:pointer;color:var(--blue);font-size:13px}.read-notes p{margin:12px 0 0}
@keyframes enter{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important;transition:none!important}}
@media(min-width:1550px){.slide{padding:50px 60px}.cover{padding:65px 60px 40px}.slide-title{font-size:43px}.slide-deck{font-size:18px}.bullets li{font-size:20px}.code-panel pre{font-size:17px}.point-list li{font-size:18px}.point-list li span{font-size:16px}.cover h1{font-size:64px}.goal-row h3{font-size:21px}.goal-row p{font-size:17px}.slide-body{max-width:1400px;width:100%;margin:0 auto}.cover-description{font-size:21px}}
@media(max-width:1100px){.workspace{grid-template-columns:190px 1fr}.sidebar{padding:28px 12px 20px}.main{padding:20px 23px 0}.slide{padding:28px 30px}.cover{padding:38px 32px 28px}.progress-track{margin:0 -23px}.two-col,.concept-layout,.two-col.wide-code{gap:22px}.cover-layout{gap:22px;grid-template-columns:1.1fr .9fr}.type-visual-main{padding:18px}.mini-code{font-size:12px}.cover-route{margin-top:25px}.keyboard-tip{display:none}.cover-meta{gap:15px;flex-wrap:wrap}.code-panel pre{font-size:12px;padding:14px 12px}.slide-deck{margin-bottom:20px}.goal-list{gap:13px}}
@media(max-width:820px){.topbar{height:70px;padding:0 20px}.brand-sub{display:none}.brand strong{font-size:15px}.brand-mark{width:36px;height:36px;font-size:22px}.topbar-tools{gap:10px}.icon-btn span{display:none}.view-switch button{padding:6px 12px}.workspace{display:block;min-height:calc(100dvh - 70px)}.sidebar{display:none}.main{height:calc(100dvh - 70px);padding:17px 18px 0}.cover h1{font-size:38px}.cover-description{font-size:15px}.cover-layout{grid-template-columns:1.15fr .85fr}.type-cpp{font-size:66px;letter-spacing:-7px}.mini-code{font-size:10px}.cover-meta{font-size:12px}.route-item{font-size:11px}.cover-route{gap:10px}.slide-title{font-size:28px}.progress-track{margin:0 -18px}.reading .main{height:auto;min-height:calc(100dvh - 70px)}.goal-layout{grid-template-columns:.7fr 1.3fr;gap:22px}.goal-summary h3{font-size:22px}.goal-summary{padding-right:20px}}
@media(max-width:600px){.topbar{padding:0 14px}.brand{gap:9px}.brand strong{font-size:13px}.view-switch button{font-size:12px;padding:6px 9px}.main{padding:12px 12px 0}.stage-context{margin-bottom:10px;font-size:12px}.stage-context .text-btn{font-size:12px}.slide{padding:24px 22px;border-radius:9px}.slide-title{font-size:26px}.slide-deck{font-size:14px}.slide-kicker{font-size:10px;letter-spacing:1px}.cover{padding:30px 23px}.cover-layout,.concept-layout,.two-col,.two-col.wide-code,.goal-layout{display:grid;grid-template-columns:1fr;gap:24px;height:auto}.cover h1{font-size:38px;line-height:1.25}.cover-chapter{margin-bottom:20px}.cover-description{font-size:14px;margin-bottom:0}.cover-meta{margin-top:20px;gap:18px}.type-visual{display:none}.cover-route{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:28px}.route-item{font-size:13px}.cover .slide-body{min-height:100%}.goal-summary{border-right:0;border-bottom:1px solid var(--line);padding:0 0 20px}.goal-summary .huge{font-size:52px;float:left;margin-right:20px}.goal-summary h3{font-size:21px;margin-bottom:4px}.goal-summary p{font-size:13px;margin-bottom:0}.goal-row h3{font-size:17px}.goal-row p{font-size:14px}.concept-layout .prose p{font-size:16px}.big-definition{font-size:22px!important}.code-panel pre{font-size:12px;max-height:none}.present-footer{min-height:65px;padding:10px 0}.present-footer .text-btn{font-size:12px;padding-left:1px}.page-controls{gap:10px}.page-count{font-size:11px;gap:7px}.nav-btn{width:32px;height:32px}.progress-track{margin:0 -12px}#outline-list{grid-template-columns:1fr}.slide::after{bottom:9px;right:16px;font-size:10px}.reading .slide{min-height:0;margin-bottom:0}.reading .cover{min-height:490px}.reading .slide-body{min-height:0}.reading .read-notes{margin-top:24px}}
@media(max-height:720px) and (min-width:821px){.topbar{height:66px}.workspace{min-height:calc(100dvh - 66px)}.main,.sidebar{height:calc(100dvh - 66px)}.main{padding-top:14px}.stage-context{margin-bottom:10px;min-height:25px}.slide{padding:25px 35px}.cover{padding:28px 38px 24px}.cover h1{font-size:43px}.cover-description{font-size:15px}.cover-meta{margin-top:16px}.cover-route{margin-top:18px;padding-top:17px}.cover-chapter{margin-bottom:15px}.slide-title{font-size:29px}.slide-deck{font-size:14px;margin-bottom:16px}.present-footer{min-height:59px;padding:8px 0}.type-cpp{font-size:85px}.mini-code{font-size:12px}.goal-summary .huge{font-size:55px}.goal-list{gap:11px}.goal-row h3{font-size:16px}.goal-row p{font-size:13px}.code-panel pre{font-size:12px;padding:12px 16px}.prose p{font-size:16px}.big-definition{font-size:22px!important}.bullets li{margin-bottom:10px;font-size:15px}.point-list li{font-size:14px;margin-bottom:12px}.point-list li span{font-size:13px}.note{font-size:12px;padding:10px 13px;margin-top:12px}}
@media print{body{background:white}.topbar,.sidebar,.stage-context,.present-footer,.progress-track,dialog,.read-notes,.copy-btn,#toast{display:none!important}.workspace{display:block}.main{height:auto!important;padding:0!important}.slide{display:flex!important;max-height:none!important;min-height:0!important;height:auto!important;border:0;border-radius:0;box-shadow:none;page-break-after:always;break-after:page;padding:30px!important;overflow:visible!important}.slide-body{min-height:0}.code-panel{print-color-adjust:exact;-webkit-print-color-adjust:exact}.code-panel pre{max-height:none}.cover{min-height:600px!important}.type-visual{print-color-adjust:exact;-webkit-print-color-adjust:exact}}