:root{font-family:Inter,-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;color:#18385d;background:#f2f6fa;--blue:#126af3;--line:#dce7f2;--muted:#6b829c}*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit}button,a,input,select{-webkit-tap-highlight-color:transparent}button,a,summary{cursor:pointer}button{color:inherit}a{color:var(--blue);text-decoration:none}[hidden]{display:none!important}button:disabled{cursor:default;opacity:.5}button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible,canvas:focus-visible,summary:focus-visible{outline:3px solid #7db7ff;outline-offset:3px}button,select{min-height:36px;border:1px solid var(--line);border-radius:7px;background:#fff;font-size:12px;padding:7px 10px}button:hover:not(:disabled){border-color:#8cb6ec;background:#eef5ff}button.active,button[aria-pressed=true]{background:#e1edff;border-color:#a7c8f8;color:#0759c9}.lab-header{height:72px;padding:0 24px;display:flex;align-items:center;gap:30px;background:#fff;border-bottom:1px solid var(--line)}.lab-brand{display:flex;align-items:center;gap:10px;color:#163659;font-size:20px;font-weight:700;white-space:nowrap}.lab-brand>span{display:grid;place-items:center;width:35px;height:35px;border-radius:8px;color:#fff;background:var(--blue);font-size:27px}.lab-header nav{display:flex;align-self:stretch;gap:24px}.lab-header nav a{display:flex;align-items:center;color:#637e9b;font-size:14px;border-bottom:3px solid transparent}.lab-header nav a[aria-current]{color:var(--blue);border-color:var(--blue);font-weight:650}.site-return{margin-left:auto;white-space:nowrap;font-size:12px}.lab-main{max-width:1850px;padding:18px 24px;margin:auto}.region-bar{display:flex;align-items:center;gap:8px}.region-bar>button{min-width:84px}.more-regions{margin-left:auto;position:relative;font-size:12px;color:var(--muted)}.more-regions summary{padding:9px 0;min-height:36px}.more-regions summary span{font-size:10px;margin-left:7px;color:#8b9db1}.more-regions>div{position:absolute;right:0;top:100%;z-index:10;padding:12px;background:#fff;border:1px solid var(--line);border-radius:9px;box-shadow:0 8px 22px #14395b13;display:grid;grid-template-columns:repeat(2,110px);gap:7px}.lab-heading{display:flex;align-items:center;justify-content:space-between;gap:20px;margin:19px 0 17px}.lab-heading h1{font-size:27px;margin:0 0 7px;letter-spacing:-.5px}.lab-heading p{font-size:13px;color:var(--muted);margin:0;line-height:1.7}.lab-heading>span{font-size:12px;color:#5c7d9e;white-space:nowrap}.lab-status{font-size:13px;padding:11px 14px;margin-bottom:12px;border:1px solid #cfe0f5;background:#eaf3ff;border-radius:8px;color:#40668e;line-height:1.7}.lab-status.error{background:#fff2ed;color:#a4503c;border-color:#edcaba}.lab-status button{margin-left:12px}.reference-angle-note{font-size:12px;color:#4b7095;background:#eaf3ff;padding:10px 12px;border-radius:7px}.lab-workbench{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr) 238px;gap:14px;align-items:start}.vascular-panel{min-width:0;background:#fff;border:1px solid var(--line);border-radius:11px;overflow:hidden}.panel-head{height:52px;padding:0 14px;display:flex;align-items:center;justify-content:space-between;gap:10px}.panel-head h2{font-size:14px;margin:0;white-space:nowrap}.panel-head h2 span{font-size:10px;font-weight:400;color:#81a0b9;margin-right:8px}.panel-head button{min-height:30px;font-size:11px}.panel-head>span{font-size:11px;color:#5d7e9e;white-space:nowrap}.vascular-stage{position:relative;height:clamp(440px,calc(100dvh - 342px),650px);min-width:0;overflow:hidden;background:#edf6f8}.projection-panel .vascular-stage{background:#06111a}.vascular-stage canvas{display:block;width:100%;height:100%;touch-action:none;outline-offset:-3px}.anatomy-panel canvas{cursor:grab}.anatomy-panel canvas:active{cursor:grabbing}.branch-labels{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.stage-instruction{position:absolute;bottom:12px;left:12px;right:12px;text-align:center;font-size:10px;color:#63869b;pointer-events:none}.projection-kind{position:absolute;top:12px;right:12px;font-size:10px;color:#839eaf;pointer-events:none}.branch-label{position:absolute;max-width:160px;transform:translate(-50%,-50%);padding:4px 7px;border-radius:5px;background:#f9fdffed;color:#224e70;border:1px solid #cde0eb;font-size:11px;font-weight:600;line-height:1.4;text-align:center;box-shadow:0 2px 6px #14395b0a}.projection-panel .branch-label{background:#102b3ce8;color:#ddf2ff;border-color:#345b71}.panel-caption{font-size:11px;color:#728aa3;line-height:1.7;margin:0;padding:10px 13px;min-height:41px}.lab-controls{max-height:calc(100dvh - 210px);overflow:auto;background:#fff;border:1px solid var(--line);border-radius:10px;padding:16px;scrollbar-width:thin}.lab-controls>div,.lab-controls>p{margin:0 0 17px}.lab-controls>div+div{border-top:1px solid #e6eef7;padding-top:16px}.lab-controls h2{font-size:14px;margin:0 0 15px}.lab-controls label{display:block;font-size:11px;color:#617e9e;margin:11px 0 7px}.angle-control output{float:right;font-size:13px;color:#145fc7;font-weight:600}.angle-control input[type=range]{width:100%;margin:9px 0 5px;accent-color:var(--blue);cursor:pointer}.range-scale{display:flex;justify-content:space-between;color:#8b9eb4;font-size:9px;margin:1px 0 18px}.range-scale:last-child{margin-bottom:0}.branch-controls select{width:100%;font-size:12px;color:#254a70;min-width:0;padding:8px 7px}.view-toggles{display:flex;gap:16px;margin-top:7px}.view-toggles label{display:flex;align-items:center;gap:5px;min-height:32px;margin:0;font-size:12px}.view-toggles input{accent-color:var(--blue)}.branch-controls details{font-size:10px;color:#8095aa;margin-top:9px;line-height:1.7}.branch-controls details p{overflow-wrap:anywhere;font-size:10px;color:#6e859e}.metric-card{background:#edf7fc;border:1px solid #d4e9f4!important;padding:12px!important;border-radius:8px}.metric-card>span{font-size:11px;color:#507b98}.metric-card>strong{display:block;color:#126af3;font-family:ui-monospace,monospace;font-size:27px;margin:4px 0}.metric-card>p{font-size:11px;margin:0;color:#557c96}.metric-card details{font-size:10px;color:#7893aa;line-height:1.7;margin-top:8px}.metric-card details p{margin-bottom:0}.subtle-note{font-size:11px;line-height:1.8;color:#7890a7}.presets>div{display:grid;grid-template-columns:1fr 1fr;gap:6px}.presets button{font-size:11px;padding:8px 5px}.compare-controls>button{width:100%;font-size:11px}.compare-controls>div{display:flex;gap:6px;margin-top:7px}.compare-controls>div button{flex:1;font-size:11px}.compare-controls p{font-size:10px;line-height:1.7;color:#8297ae;margin:9px 0 0}.teaching-examples{display:flex;justify-content:space-between;align-items:center;gap:24px;background:#fff;border:1px solid var(--line);border-radius:10px;padding:17px 19px;margin-top:16px}.teaching-examples h2{font-size:15px;margin:0 0 8px}.teaching-examples p{font-size:12px;color:#6c87a2;line-height:1.8;margin:0;max-width:610px}.example-group{display:flex;flex-wrap:wrap;gap:10px 18px;flex-shrink:0}.example-group>div{display:flex;align-items:center;gap:7px}.example-group>div>span{font-size:11px;color:#6b85a0}.example-group button{font-size:11px;padding:8px}.model-source{margin-top:17px;color:#6a839d;font-size:11px;line-height:1.9}.model-source summary{min-height:32px;padding:7px 0}.model-source>div{background:#fff;border:1px solid var(--line);border-radius:8px;padding:10px 15px}.model-source p{margin:7px 0}.lab-footer{margin-top:13px;border-top:1px solid var(--line);padding:16px 0 4px;display:flex;justify-content:space-between;font-size:10px;color:#7c92aa}.lab-loading .vascular-stage canvas,.lab-loading .branch-labels{visibility:hidden}@media(min-width:1700px){.lab-workbench{grid-template-columns:minmax(0,1fr) minmax(0,1fr) 258px}}
@media(max-width:1100px){.lab-header{gap:20px}.lab-main{padding:15px 18px}.lab-workbench{grid-template-columns:1fr 1fr}.lab-controls{grid-column:1/-1;max-height:none;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.lab-controls>div+div{border:0;padding:0}.lab-controls>div{margin-bottom:0}.lab-heading>span{display:none}.teaching-examples{align-items:flex-start;flex-wrap:wrap}.vascular-stage{height:470px}}
@media(max-width:650px){.lab-header{height:auto;min-height:100px;padding:13px 16px 0;gap:8px 14px;flex-wrap:wrap}.lab-brand{font-size:17px}.lab-brand>span{width:29px;height:29px;font-size:23px}.site-return{font-size:10px}.lab-header nav{order:3;width:100%;gap:0;justify-content:space-around;min-height:44px}.lab-header nav a{font-size:13px;min-width:120px;justify-content:center}.lab-main{padding:15px 14px}.region-bar>button{min-width:71px;font-size:12px}.more-regions{font-size:11px}.more-regions summary span{font-size:9px}.lab-heading{margin:20px 0 15px}.lab-heading h1{font-size:23px;line-height:1.45}.lab-heading p{font-size:12px;line-height:1.8}.lab-workbench{display:flex;flex-direction:column;gap:13px}.lab-controls{order:-1;display:block;width:100%;max-height:none;padding:14px}.lab-controls h2{margin-bottom:12px}.lab-controls>div+div{border-top:1px solid var(--line);padding-top:14px;margin-top:13px}.lab-controls .branch-controls,.lab-controls .metric-card,.lab-controls .presets,.lab-controls .compare-controls,.lab-controls #no-centerline-note{display:none}.angle-control{display:grid;grid-template-columns:1fr 1fr;column-gap:18px}.angle-control h2{grid-column:1/-1}.angle-control label{grid-row:2;margin-top:0;font-size:11px}.angle-control input{grid-row:3}.angle-control .range-scale{grid-row:4;margin-bottom:0}.angle-control output{font-size:12px}.vascular-panel{width:100%}.vascular-stage{height:430px}.panel-head{height:49px;padding:0 12px}.panel-head h2{font-size:13px}.panel-head>span{font-size:10px}.panel-caption{font-size:10px;padding:9px 12px}.branch-label{font-size:10px;max-width:145px}.teaching-examples{display:block;padding:15px;margin-top:14px}.example-group{display:grid;gap:12px;margin-top:14px}.example-group>div{flex-wrap:wrap}.example-group button{font-size:12px;min-height:38px}.model-source{font-size:11px}.lab-footer{line-height:1.8;gap:20px}.reference-angle-note{font-size:11px}.mobile-branch-tools{display:block}.lab-controls.show-mobile-details .branch-controls,.lab-controls.show-mobile-details .metric-card,.lab-controls.show-mobile-details .presets,.lab-controls.show-mobile-details .compare-controls{display:block}.lab-controls.show-mobile-details #no-centerline-note:not([hidden]){display:block}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}

.vascular-access{position:fixed;inset:0;z-index:1000;background:#14345466;backdrop-filter:blur(8px);display:flex;align-items:center;justify-content:center;padding:20px;overflow:auto}.vascular-access-card{width:min(380px,100%);max-height:calc(100dvh - 40px);overflow:auto;padding:28px;border:1px solid #dce7f2;border-radius:16px;background:#fff;box-shadow:0 24px 80px #0e325333;color:#17365c}.access-mark{width:36px;height:36px;display:grid;place-items:center;background:#126af3;color:white;border-radius:9px;font-size:28px;margin-bottom:17px}.vascular-access h1{font-size:22px;margin-bottom:10px}.access-notice{font-size:13px;line-height:1.8;color:#6c839e;margin-bottom:21px}.vascular-access form{display:grid;gap:10px}.vascular-access label{font-size:12px;color:#577693}.vascular-access input{width:100%;min-width:0;height:46px;padding:0 12px;border:1px solid #d3e3f2;border-radius:7px;background:#f7faff;color:#17365c;font-size:14px}.vascular-access button{height:44px;background:#126af3;color:#fff;border:0;border-radius:7px;font-size:13px;font-weight:600;margin-top:3px}.vascular-access button:disabled{opacity:.55}.access-error{font-size:12px;color:#ad5147;line-height:1.7}.access-links{display:flex;justify-content:center;align-items:center;gap:11px;margin-top:20px;font-size:11px;color:#6c88a4}.access-links a{padding:5px 0}.access-links a:hover{color:#126af3}@media(max-height:550px){.vascular-access{align-items:flex-start}.vascular-access-card{padding:22px}.access-mark{margin-bottom:12px}}
.access-links .access-contact-trigger{height:auto;min-height:0;margin:0;border:0;padding:5px 0;background:none;color:#6c88a4;font-size:11px;font-weight:400}.access-links .access-contact-trigger:hover{color:#126af3}.access-contact-dialog{position:fixed;inset:0;margin:auto;border:1px solid #dce7f2;border-radius:15px;width:min(350px,calc(100vw - 32px));max-height:calc(100dvh - 32px);overflow:auto;background:#fff;padding:25px;color:#17365c;box-shadow:0 18px 60px #15345433}.access-contact-dialog::backdrop{background:#14345480}.access-contact-dialog h2{font-size:19px;margin-bottom:10px}.access-contact-dialog p{font-size:12px;color:#7189a2}.access-contact-dialog figure{margin:18px 0 0;text-align:center}.access-contact-dialog img{width:100%;max-width:240px;height:auto;display:block;margin:auto}.access-contact-dialog figcaption{font-size:11px;color:#7189a2;margin-top:12px;line-height:1.8}.access-contact-dialog .access-contact-close{position:absolute;right:12px;top:12px;width:30px;height:30px;min-height:30px;margin:0;background:#eef4fa;border:0;border-radius:50%;color:#597b9e;font-size:20px;font-weight:400;line-height:1}

.camera-tools{position:absolute;top:12px;left:12px;right:12px;display:flex;gap:5px;pointer-events:none}.camera-tools button{pointer-events:auto;background:#ffffffec;font-size:10px;min-height:30px;padding:5px 8px}.camera-tools #zoom-in{margin-left:auto}.camera-tools #zoom-in,.camera-tools #zoom-out{width:30px;padding:4px;font-size:16px}.view-toggles{flex-wrap:wrap;gap:2px 12px}#mobile-detail-toggle{display:none}@media(max-width:650px){.lab-controls #mobile-detail-toggle{display:block;width:100%;min-height:40px;margin-top:12px;color:#126af3;font-size:12px}.camera-tools button{min-height:34px}}

/* Keep the lesson beside the visible vascular comparison. */
.teaching-examples{margin-top:0;margin-bottom:15px}.vascular-stage{height:clamp(420px,calc(100dvh - 430px),570px)}.lab-controls{max-height:calc(100dvh - 340px)}
.patient-direction{position:absolute;transform:translate(-50%,-50%);color:#4d7b90;background:#f3fbfddd;border:1px solid #d6e8ee;border-radius:4px;padding:2px 4px;font-size:10px;font-family:ui-monospace,monospace;font-weight:600}#mobile-layout-toggle{display:none}
@media(max-width:1100px){.lab-controls{max-height:none}}
@media(max-width:650px){.teaching-examples{padding:12px;margin-bottom:13px}.teaching-examples h2{font-size:13px;margin-bottom:6px}.teaching-examples p{font-size:10px;line-height:1.6}.example-group{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin-top:9px}.example-group>div{display:grid;grid-template-columns:1fr 1fr;gap:5px}.example-group>div>span{grid-column:1/-1;font-size:10px}.example-group button{min-height:36px;font-size:11px;padding:6px 3px}.lab-workbench{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));align-items:start}.lab-controls{grid-column:1/-1;order:0;margin-bottom:0;padding:12px}.lab-controls:not(.show-mobile-details){position:sticky;top:6px;z-index:12;box-shadow:0 6px 17px #173b5711}.lab-controls #mobile-detail-toggle,.lab-controls #mobile-layout-toggle{display:inline-block;width:calc(50% - 4px);min-height:36px;margin-top:10px;font-size:11px}.lab-controls #mobile-layout-toggle{margin-left:4px;color:#4d7096}.angle-control h2{font-size:13px;margin-bottom:10px}.range-scale{font-size:8px}.vascular-stage{height:300px}.panel-head{height:70px;padding:9px 10px;align-items:flex-start;justify-content:center;flex-direction:column;gap:5px}.panel-head h2{font-size:12px}.panel-head h2 span{display:none}.panel-head button{min-height:26px;font-size:9px;padding:4px 7px}.panel-head>span{font-size:8px;white-space:normal;line-height:1.5}.panel-caption{display:none}.camera-tools{left:7px;right:7px;top:8px;gap:4px;flex-wrap:wrap}.camera-tools button{font-size:8px;padding:4px 5px;min-height:30px}.camera-tools #zoom-in,.camera-tools #zoom-out{width:24px;font-size:14px}.stage-instruction{font-size:8px;bottom:7px;left:5px;right:5px}.projection-kind{font-size:8px;right:7px;top:9px}.branch-label{font-size:9px;max-width:calc(100% - 14px);padding:3px 4px}.patient-direction{font-size:8px;padding:1px 3px}.lab-workbench.stacked-windows .vascular-panel{grid-column:1/-1}.lab-workbench.stacked-windows .vascular-stage{height:320px}}
@media(max-width:650px){.lab-controls{order:-1}}

.lab-controls{position:relative}.controls-scroll-hint{position:sticky;bottom:-16px;margin:12px -16px -16px!important;padding:17px 16px 11px;background:linear-gradient(#ffffff00,#fffffff5 32%,#fff);color:#567fa8;font-size:10px;line-height:1.5;text-align:center;pointer-events:none}

.learning-shell{margin:0 0 15px}.learning-mode{display:flex;gap:6px;margin-bottom:9px}.learning-mode button{min-height:40px;padding:8px 20px;font-size:13px}.learning-card{display:flex;align-items:flex-start;gap:20px;padding:16px 19px;background:linear-gradient(115deg,#e9f5ff,#f7fcff);border:1px solid #cfe4f5;border-radius:11px}.learning-copy{flex:1;min-width:0}.learning-kicker{font-size:10px;color:#497c9e;letter-spacing:.4px}.learning-card h2{font-size:18px;margin:6px 0 8px;color:#164c79}.learning-card p{font-size:12px;line-height:1.8;margin:5px 0;color:#4a6e8a}.learning-card #learning-detail{display:grid;grid-template-columns:1fr 1fr;gap:0 20px}.learning-card #learning-detail p{font-size:11px}.learning-detail strong{color:#224f74}.learning-action{padding:8px 11px;border-left:3px solid #1f8fc4;background:#ffffffb3;border-radius:0 5px 5px 0;color:#155c83!important}.learning-actions{display:flex;flex-wrap:wrap;align-items:center;justify-content:flex-end;gap:6px;max-width:210px;padding-top:20px}.learning-actions button{min-height:40px;color:#0a68bf}.learning-card details{font-size:10px;color:#64869f;margin-top:7px}.learning-card details a{display:block;line-height:1.8}.learning-card #learning-feedback{padding:10px 12px;background:#fff;border-radius:6px}.learning-card #learning-feedback.correct{border-left:3px solid #16a88b;color:#147866}.learning-card #learning-feedback.try-again{border-left:3px solid #d8a247;color:#8b641e}.quiz-blind .branch-controls,.quiz-blind #metric-card,.quiz-blind #no-centerline-note{display:none!important}body[data-learning-mode=quiz] .branch-controls{display:none!important}.label-leader{position:absolute;height:1px;background:#69a7c4;transform-origin:0 50%;opacity:.8}.label-anchor{position:absolute;width:5px;height:5px;border-radius:50%;background:#2576a0;border:1px solid #e1f4ff;transform:translate(-50%,-50%)}.projection-panel .label-anchor{background:#c0e8fa}.lab-loading .learning-mode button{pointer-events:none;opacity:.5}
@media(min-width:1101px){body[data-learning-mode=free] .learning-card #learning-detail{grid-template-columns:repeat(3,minmax(0,1fr))}.learning-card{max-height:238px;overflow:auto}}
@media(max-width:650px){.learning-mode{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:5px}.learning-mode button{padding:8px 4px;font-size:12px;min-height:42px}.learning-card{padding:13px;display:block}.learning-card h2{font-size:17px;line-height:1.5}.learning-card p{font-size:12px}.learning-card #learning-detail{display:block}.learning-card #learning-detail p{font-size:11px}.learning-actions{padding-top:9px;max-width:none;justify-content:flex-start}.learning-actions button{min-height:42px;flex:1}.learning-kicker{font-size:10px}}