/* SnapStat: a quiet study surface with a dedicated dark code canvas. */
:root{color-scheme:light;--bg:#f5f7fb;--surface:#fff;--text:#19253e;--muted:#5b6980;--line:#e1e7f0;--accent:#315ef4;--mint:#247665;--shadow:0 8px 30px #25355508;font-family:Inter,'Segoe UI',Arial,sans-serif}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font-size:15px;line-height:1.5}[hidden]{display:none!important}button,input,select{font:inherit}button,a,summary{-webkit-tap-highlight-color:transparent}button{cursor:pointer;border:1px solid transparent;border-radius:10px;background:#edf1f8;color:#344360;padding:10px 15px;font-weight:600;font-size:13px;line-height:1.4;transition:background .15s,color .15s,box-shadow .15s;min-height:40px}button:hover{background:#e0e7f4;color:#1c387a}button:active{transform:translateY(1px)}button:disabled{opacity:.4;cursor:default;transform:none}button.primary,#practice,#reveal-practice{background:var(--accent);color:#fff;box-shadow:0 3px 9px #315ef426}button.primary:hover,#practice:hover,#reveal-practice:hover{background:#234bce}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #547cfa;outline-offset:3px}input,select{color:var(--text);background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:10px 12px;min-height:40px;min-width:0}select{cursor:pointer}a{color:#2853d0;text-underline-offset:3px}h1,h2,h3,p{margin-top:0}h1,h2,h3{line-height:1.3}h1{font-size:40px;font-weight:730;letter-spacing:-1.5px;margin-bottom:14px}h1 span{color:var(--accent)}h2{font-size:20px;letter-spacing:-.4px}h3{font-size:16px}p{line-height:1.75}.muted{color:var(--muted)}.eyebrow{font-size:10px;font-weight:750;letter-spacing:1.65px;color:#51699b;margin-bottom:12px}.warning{color:#84500c;background:#fff5df;border-left:3px solid #dca238;padding:12px;font-size:13px;line-height:1.7}.pill,.status{display:inline-block;font-size:11px;border-radius:6px;padding:5px 9px;background:#edf2ff;color:#3156a4}.status.good{background:#e6f5ee;color:#247665}
header{height:80px;background:var(--surface);display:flex;align-items:center;gap:38px;padding:0 32px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-size:23px;font-weight:750;letter-spacing:-.6px;color:var(--text)}.brand-logo{width:44px;height:44px;object-fit:contain;padding:7px;background:#315ef4;border-radius:13px}.brand small{display:block;font-size:9px;letter-spacing:1.7px;color:var(--muted);margin-top:2px}.version-control{display:flex;gap:3px;background:#edf1f7;padding:4px;border-radius:11px}.version-control button{background:transparent;min-height:32px;padding:6px 15px}.version-control button.active{background:#fff;color:#315ef4;box-shadow:0 2px 6px #1e305512}.header-end{display:flex;align-items:center;gap:18px;margin-left:auto}.local{font-size:10px;font-weight:700;letter-spacing:1.2px;color:#247665}.header-end button{background:transparent;color:var(--muted);font-weight:500}.toolbar{display:flex;align-items:center;gap:10px;padding:12px 32px;background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20;min-height:68px}.toolbar nav{display:flex;background:#f0f3f9;padding:4px;border-radius:12px;margin-right:15px}.toolbar nav button{background:transparent;color:var(--muted);padding:9px 15px;white-space:nowrap}.toolbar nav button.active{background:#fff;color:var(--accent);box-shadow:0 2px 6px #17284510}.search-wrap{display:flex;align-items:center;gap:9px;background:#f6f8fc;border:1px solid var(--line);padding:0 12px;border-radius:11px;flex:1;max-width:540px}.search-wrap input{background:transparent;border:0;flex:1;width:100%;font-size:13px}.search-wrap>span{color:#71809b;font-size:24px}kbd{font-size:10px;border:1px solid #d7deea;padding:1px 4px;border-radius:3px;color:#8190a5}#notice:not(:empty){padding:12px 32px;background:#fff5df;color:#795015;font-size:13px}#questions-view{display:grid;grid-template-columns:230px minmax(0,1fr);max-width:1500px;margin:0 auto}.study-sidebar{padding:32px 18px;border-right:1px solid var(--line);position:sticky;top:68px;max-height:calc(100dvh - 68px);overflow:auto}.study-sidebar h2{font-size:15px;margin-bottom:18px}#categories{display:grid;gap:3px}#categories button{background:transparent;text-align:left;display:flex;align-items:center;justify-content:space-between;gap:8px;font-size:12px;font-weight:500;line-height:1.45;padding:9px 12px;color:var(--muted);min-height:36px}#categories button:hover{background:#eaf0fb}#categories button.active{background:#e5edff;color:#244ec5;font-weight:650}#categories button span{font-size:10px;color:#72809a}.sidebar-note{margin-top:25px;padding:20px 12px;border-top:1px solid var(--line);font-size:12px;color:var(--muted)}.sidebar-note strong{display:block;color:var(--text);margin:9px 0}.sidebar-note p{margin-bottom:6px}.sidebar-note button{background:none;padding:6px 0;font-size:12px;color:var(--accent)}.mini-icon{font:22px Consolas,monospace;color:var(--accent)}.question-main{padding:38px 48px 56px;min-width:0;max-width:1160px;width:100%;margin:0 auto}.section-top{display:flex;justify-content:space-between;gap:20px;align-items:center;margin-bottom:30px}.section-top p:not(.eyebrow){color:var(--muted);font-size:14px;margin-bottom:0}.source-stat{display:flex;align-items:center;gap:14px;padding:18px 22px;border:1px solid var(--line);border-radius:16px;background:#fff}.source-stat b{font-size:35px;font-weight:600;color:#315ef4}.source-stat span{font-size:11px;color:var(--muted);line-height:1.7}.list-header{display:flex;align-items:center;gap:12px;margin:0 0 12px}.list-header h2{font-size:18px;margin:0}.list-header>span{font-size:12px;color:var(--muted)}.list-header select{margin-left:auto;font-size:12px}.study-tools{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-bottom:20px}.study-tools select{font-size:12px}.study-tools button{background:transparent;color:var(--muted);font-size:12px}.study-tools span{margin-left:auto;font-size:12px;color:var(--muted)}#topic-select{display:none}#question-list{display:flex;flex-direction:column;gap:8px}.question-row{display:flex;align-items:center;background:#fff;border:1px solid var(--line);border-radius:13px;padding:0 10px 0 0;box-shadow:0 2px 5px #26365803;transition:border-color .15s,box-shadow .15s}.question-row:hover{border-color:#adbff1;box-shadow:0 5px 16px #315ef409}.question-open{display:flex;align-items:center;gap:18px;text-align:left;flex:1;min-width:0;background:transparent;border-radius:12px;padding:19px 20px;font-weight:500}.question-open:hover{background:#f8faff;color:var(--text)}.question-open>span:nth-child(2){flex:1}.question-open small{display:block;font-size:10px;color:#69788f;margin-bottom:5px;font-weight:500}.question-open strong{font-size:15px;line-height:1.5;font-weight:600}.question-open>span:last-child{color:#7b8cab}.row-number{font-size:11px;color:#91a0b5;font-weight:600;min-width:20px}.question-row>button:last-child{background:transparent;font-size:20px;color:#64779a;min-width:42px;padding:9px}.question-row>button[aria-pressed=true]{color:#315ef4}.empty{padding:30px;border:1px dashed #c4cfe0;border-radius:12px;background:#fff;color:var(--muted)}#reading-pane{background:#fff;border:1px solid var(--line);border-radius:20px;padding:32px;box-shadow:var(--shadow);scroll-margin-top:85px}#answer-title{font-size:29px;line-height:1.35;letter-spacing:-.7px;margin:15px 0 25px;max-width:850px}#answer-title:focus{outline:none}.reading-nav{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.reading-nav:first-child{margin-bottom:25px}.reading-nav:first-child button{background:none;padding-left:0;color:#5f7090;font-weight:500}.reading-nav span{font-size:11px;color:var(--muted)}.reading-actions{display:flex;gap:10px;flex-wrap:wrap;margin:25px 0}.spoken-answer{background:#eff4ff;border-radius:13px;padding:24px 26px;border:1px solid #dce7ff}.spoken-answer .eyebrow{color:#3f62b2;font-size:10px}.spoken-answer p{font-size:18px;color:#253b66;line-height:1.85;margin:8px 0 0}.answer-detail,.guide-detail{padding:18px 0;border-bottom:1px solid var(--line);line-height:1.75}.answer-detail summary,.guide-detail summary{cursor:pointer;font-size:14px;font-weight:650;color:#35486b}.answer-detail p,.guide-detail p{color:var(--muted);margin:14px 0}.answer-detail strong{font-size:14px}.followups{margin-top:26px}.followups h3{margin-bottom:5px;font-size:16px}.followups>p{font-size:12px;color:var(--muted);margin-bottom:12px}.follow-link{display:flex;justify-content:space-between;gap:18px;align-items:center;padding:13px 15px;border-radius:9px;background:#f7f9fd;border:1px solid #e9edf5;text-decoration:none;font-size:13px;font-weight:550;margin:8px 0;line-height:1.6;color:#3153a0}.follow-link:hover{background:#edf3ff;border-color:#b8cafa}.follow-link>span:last-child{flex:none}.answer-verification{background:#fff7e6;color:#75541b;padding:16px;border-radius:10px;font-size:13px;margin:15px 0}.answer-verification p{color:inherit}.comparison-scroll{overflow:auto;max-width:100%;margin:20px 0}.comparison-table{width:100%;min-width:560px;border-collapse:collapse;font-size:12px;line-height:1.7}.comparison-table caption{text-align:left;color:var(--muted);margin-bottom:12px}.comparison-table th,.comparison-table td{border:1px solid var(--line);padding:14px;vertical-align:top;text-align:left}.comparison-table thead{background:#edf3ff}.comparison-table small{display:block;margin-top:9px;font-weight:400}.evidence-link{max-width:100%;overflow-wrap:anywhere;text-align:left;font-size:11px;margin:4px 0}.text-action{color:var(--accent);background:none;padding-left:0}.app-footer{display:flex;justify-content:space-between;gap:15px;padding:16px 28px;font-size:10px;border-top:1px solid var(--line);color:#718099;background:#fff}
/* Source workspace: fixed-height editor, readable explanation, optional files. */
#code-view{display:grid;grid-template-columns:210px minmax(0,1fr) 390px;grid-template-rows:minmax(0,1fr);height:calc(100dvh - 194px);min-height:540px;overflow:hidden}#file-panel,#details{min-height:0;height:100%;overflow:auto;background:#fff;min-width:0}#file-panel{border-right:1px solid var(--line)}#details{border-left:1px solid var(--line)}.panel-title{display:flex;justify-content:space-between;align-items:center;padding:14px 16px;font-size:10px;letter-spacing:1.3px;font-weight:750;color:#627492;background:#fff;position:sticky;top:0;z-index:2;border-bottom:1px solid #edf0f5}.panel-title button{background:none;padding:3px 8px;min-height:30px;font-size:19px;color:#7788a3}#file-panel input,#file-panel select{width:calc(100% - 24px);margin:10px 12px 0;font-size:11px;min-height:36px}#files{max-height:26vh;overflow:auto;padding:9px;font-size:11px}#files summary{padding:7px;color:#657793;cursor:pointer;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}#files button{display:block;width:100%;text-align:left;background:none;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;padding:7px;font-size:11px;font-weight:500;min-height:30px}#files button.active{background:#eaf0ff;color:#315ef4}#outline{padding:12px 7px}#outline button{display:block;text-align:left;width:100%;padding:9px 7px;background:none;font:11px Consolas,monospace;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}#outline button:hover{background:#edf3ff}#outline button span{color:#315ef4;margin-right:7px}#outline button small{display:block;white-space:normal;margin:5px 0 0 14px;color:#8190a5;font:10px 'Segoe UI',sans-serif}.editor{display:flex;flex-direction:column;min-width:0;height:100%;min-height:0;overflow:hidden;background:#131c2f;color:#dfe7f8}.filebar{display:flex;align-items:center;gap:10px;padding:10px 13px;background:#1c2941;border-bottom:1px solid #2b3a53;font-size:12px}.filebar button{background:#293a56;color:#dce7fb;font-size:11px;padding:7px 10px;min-height:32px}#toggle-details{margin-left:auto}.badge{font-size:8px;letter-spacing:1px;color:#9cdac4;background:#25483f;padding:4px 6px;border-radius:4px}.lesson-bar{display:flex;align-items:center;gap:5px;flex-wrap:wrap;padding:10px 12px;border-bottom:1px solid #26364e}.lesson-bar>span{font-size:10px;color:#a1b3cf;margin-right:3px}.lesson-bar button{background:#213450;color:#c5d7f7;font-size:10px;font-weight:500;padding:5px 8px;min-height:28px;border-radius:6px}.lesson-bar button:hover{background:#31517e}.editor-meta{display:flex;justify-content:space-between;gap:10px;padding:10px 14px;color:#a3b2ca;font-size:10px;overflow-wrap:anywhere}.jumpbar{display:flex;align-items:center;gap:8px;flex-wrap:wrap;padding:0 12px 12px;font-size:10px;color:#b4c3d9}.jumpbar input{background:#1d2a41;color:#e1eaff;border-color:#344561;width:65px;min-height:30px;padding:5px 7px;font-size:11px;border-radius:6px}.jumpbar button{min-height:30px;padding:5px 8px;background:#293a56;color:#dce7fb;font-size:10px;border-radius:6px}#code-scroll{height:0;flex:1 1 0;min-height:0;position:relative;overflow:auto;scroll-behavior:auto}#code-space{width:1px}#code-lines{position:absolute;top:0;left:0;min-width:100%}.code-line{height:26px;line-height:26px;white-space:pre;display:flex;min-width:max-content;font:12px/26px Consolas,'Courier New',monospace;padding-right:24px}.code-line.selected{background:#223957}.lineno{position:sticky;left:0;flex:0 0 56px;width:56px;border:0;border-radius:0;background:#131c2f;color:#8194b2;padding:0 12px 0 0;font:10px/26px Consolas,monospace;min-height:26px;height:26px;text-align:right;margin-right:12px}.code-line.selected .lineno{background:#223957;color:#b6cdf9}.lineno:hover{background:#30486b;color:#fff}.code-text{padding:0 5px;user-select:text}.token{cursor:help}.token:hover{background:#36517c}.tok-keyword{color:#c5afff}.tok-string{color:#a7dcae}.tok-number{color:#efca91}.tok-comment{color:#9babbe}.tok-type{color:#8ed4e2}.editor-footer{display:flex;justify-content:space-between;gap:8px;font-size:9px;color:#a2b2ca;border-top:1px solid #2b3a53;padding:9px 12px}.collapsed-files{grid-template-columns:minmax(0,1fr) 390px!important}.collapsed-files #file-panel{display:none}.collapsed-details{grid-template-columns:210px minmax(0,1fr)!important}.collapsed-details #details{display:none}.collapsed-files.collapsed-details{grid-template-columns:minmax(0,1fr)!important}#explanation{padding:22px;font-size:13px;line-height:1.8;overflow-wrap:anywhere}#explanation h2{font-size:21px;margin-bottom:9px}#explanation h3{font-size:13px;margin:22px 0 9px;font-weight:700;color:#334967}#explanation p{color:#556680;margin:8px 0 15px}.location{font-size:10px;color:#74829a!important}.guide-summary{background:#eff4ff;border-radius:12px;padding:15px 17px;margin:20px 0}.guide-summary h3{color:#3153a0!important;margin:0 0 6px!important}.guide-summary p{color:#294369!important;font-size:14px;margin:0!important;line-height:1.8}.guide-steps{padding-left:24px;margin:12px 0 22px;color:#4c5f7b}.guide-steps li{padding:0 0 12px 7px}.guide-steps li::marker{color:#315ef4;font-weight:700}.example-box{border:1px solid #d8eadd;background:#f1f8f3;padding:16px;border-radius:12px;margin:20px 0}.example-box h3{margin:0 0 7px!important;color:#347453!important}.example-box p{margin:0!important;color:#375d49!important;font-size:12px}.example-box button{margin-top:15px!important;max-width:100%}.guide-detail summary{font-size:12px}.guide-detail{padding:15px 0}.guide-detail dl{margin:14px 0}.guide-detail dt{font:600 13px Consolas,monospace;color:#315ef4}.guide-detail dd{margin:3px 0 15px;color:#586a83}.guide-detail select{display:block;width:100%;margin-top:7px}#explanation button{font-size:11px;text-align:left;margin:4px 0;max-width:100%;overflow-wrap:anywhere}#explanation>button{display:block;width:100%;background:#f1f5fc;color:#365ba7;padding:11px 13px;line-height:1.6}#explanation pre,dialog pre{font:11px/1.7 Consolas,monospace;background:#f0f3f8;border:1px solid var(--line);padding:13px;border-radius:9px;white-space:pre-wrap;overflow:auto;max-height:230px;color:#32496a}.symbol-links{display:flex;gap:5px;flex-wrap:wrap}.symbol-links button{font-family:Consolas,monospace}.review-actions{display:flex;gap:7px;flex-wrap:wrap;margin-top:15px}#tooltip{position:fixed;z-index:100;max-width:min(330px,calc(100vw - 24px));padding:14px;background:#fff;border:1px solid #cfdbef;box-shadow:0 8px 30px #07193420;border-radius:10px;font-size:12px;color:#2d4569;pointer-events:none}.code-hit{display:block;width:100%;text-align:left;margin:8px 0;background:#fff;border:1px solid var(--line);padding:15px;font-size:12px}.code-hit small{display:block;font-weight:400;color:var(--muted);margin-top:7px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}#code-results h2{margin-top:30px}#code-results:empty{display:none}
dialog{width:min(760px,94vw);max-height:88dvh;background:#fff;border:1px solid var(--line);border-radius:20px;color:var(--text);padding:28px;box-shadow:0 25px 100px #11275030}dialog::backdrop{background:#12243b66;backdrop-filter:blur(4px)}.modal-head{display:flex;justify-content:space-between;align-items:center;gap:15px;margin-bottom:23px}.modal-head h2{margin:0}.modal-head button{font-size:20px;padding:5px 12px}#modal-body{font-size:14px;line-height:1.8}#modal-body article{padding:15px 0;border-bottom:1px solid var(--line)}#modal-body article button{margin:5px 7px 0 0}#modal-body h2{font-size:25px}.review-actions button{margin-top:8px}ul{padding-left:22px}
@media(min-width:1600px){#code-view{grid-template-columns:230px minmax(0,1fr) 460px}.collapsed-files{grid-template-columns:minmax(0,1fr) 460px!important}.collapsed-details{grid-template-columns:230px minmax(0,1fr)!important}#explanation{padding:28px}}
@media(max-width:1100px){header{padding:0 22px;gap:25px}.toolbar{padding:12px 22px;gap:8px}.toolbar nav{margin-right:0}.toolbar nav button{padding:9px 10px;font-size:12px}.local{display:none}#questions-view{grid-template-columns:195px minmax(0,1fr)}.question-main{padding:30px 25px}.source-stat{display:none}#code-view{grid-template-columns:175px minmax(0,1fr) 330px}.collapsed-files{grid-template-columns:minmax(0,1fr) 330px!important}.collapsed-details{grid-template-columns:175px minmax(0,1fr)!important}#explanation{padding:18px}.search-wrap kbd{display:none}}
@media(max-width:750px){header{height:70px;padding:0 16px;gap:16px}.brand{font-size:20px;gap:9px}.brand-logo{width:38px;height:38px;padding:6px;border-radius:11px}.brand small{font-size:7px;letter-spacing:1.3px}.version-control{margin-left:auto}.version-control button{padding:6px 11px;font-size:12px}.header-end{display:none}.toolbar{padding:10px 12px;flex-wrap:wrap;gap:7px;position:sticky;top:0;min-height:114px}.toolbar nav{flex:1;padding:3px}.toolbar nav button{flex:1;padding:9px 7px;font-size:11px;min-height:35px}.toolbar>button{padding:9px;font-size:11px;min-height:38px}.search-wrap{flex-basis:100%;max-width:none;order:5;min-height:36px}.search-wrap input{font-size:12px;min-height:36px}#questions-view{display:block}.study-sidebar{display:none}#topic-select{display:block;width:100%}.question-main{padding:26px 16px 35px}.section-top{margin-bottom:24px}h1{font-size:31px;letter-spacing:-1px}.section-top p:not(.eyebrow){font-size:13px}.list-header{flex-wrap:wrap;gap:7px}.list-header h2{font-size:17px}.list-header select{font-size:11px;padding:8px;max-width:128px}.study-tools{gap:8px}.study-tools select{font-size:11px}.study-tools span{margin-left:0;font-size:11px}.question-open{padding:16px 12px;gap:11px}.question-open strong{font-size:13px}.question-open small{font-size:9px}.question-row{padding-right:4px}.question-row>button:last-child{min-width:36px;padding:7px;font-size:20px}.row-number{min-width:16px;font-size:10px}#reading-pane{padding:20px 17px;border-radius:15px;scroll-margin-top:130px}#answer-title{font-size:24px;letter-spacing:-.4px}.spoken-answer{padding:20px 17px}.spoken-answer p{font-size:16px;line-height:1.85}.reading-actions{gap:7px}.reading-actions button{font-size:11px;padding:10px 11px}.reading-nav button{font-size:12px}.follow-link{font-size:12px}.app-footer{padding:14px 16px;font-size:9px}.app-footer span:last-child{display:none}#code-view{height:calc(100dvh - 225px);min-height:470px;display:flex;position:relative}.editor{width:100%}#file-panel{position:absolute;left:0;top:0;bottom:0;width:min(285px,90vw);display:none;z-index:10;box-shadow:12px 0 40px #10284c30}#code-view.mobile-files #file-panel{display:block}#details{position:absolute;right:0;top:0;bottom:0;width:min(420px,100%);z-index:11;box-shadow:-12px 0 40px #10284c30}#code-view.collapsed-details #details{display:none}#explanation{padding:20px}.filebar{gap:8px;padding:10px;font-size:11px}.badge{font-size:7px}.lesson-bar{padding:8px 10px}.lesson-bar button{font-size:9px;padding:5px 7px}.editor-meta{font-size:9px;padding:9px 12px}.editor-footer span:last-child{display:none}.jumpbar{gap:6px}.lineno{width:44px;flex-basis:44px;margin-right:7px}.code-line{font-size:11px}.panel-title{padding:12px 18px}.panel-title button{min-width:36px;min-height:36px}dialog{padding:21px 18px;border-radius:15px}#modal-body h2{font-size:22px}.comparison-table{min-width:540px}.source-stat{display:none}}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
.follow-link small{display:block;font-size:10px;color:#6f819d;margin-top:3px}
.nav-short{display:none}@media(max-width:750px){.nav-full{display:none}.nav-short{display:inline}.toolbar{min-height:104px}.toolbar nav{min-width:0}.toolbar nav button{padding:8px}.toolbar>button{padding:8px}.reading-nav:first-child{gap:8px}#reading-pane{scroll-margin-top:120px}#code-view{height:calc(100dvh - 216px)}}
.mobile-changes{display:none}@media(max-width:750px){.mobile-changes{display:block;background:none;padding:0;min-height:28px;font-size:10px;color:#516a96}}
@media(min-width:751px) and (max-width:1000px){#code-view{position:relative;grid-template-columns:minmax(0,1fr) 330px}#file-panel{display:none;position:absolute;left:0;top:0;bottom:0;width:260px;z-index:12;box-shadow:12px 0 35px #10284c30}#code-view.mobile-files #file-panel{display:block}.collapsed-details{grid-template-columns:minmax(0,1fr)!important}.collapsed-files{grid-template-columns:minmax(0,1fr) 330px!important}.collapsed-files.collapsed-details{grid-template-columns:minmax(0,1fr)!important}}