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.embedded{--teal:#1d1d1f;--muted:#626268;--line:#d2d2d7;font-family:-apple-system,BlinkMacSystemFont,'Helvetica Neue','PingFang SC','Microsoft YaHei',sans-serif;color:#1d1d1f;background:#fff;-webkit-font-smoothing:antialiased;color-scheme:light}
.embedded body{background:#fff}.embedded main{width:100%;max-width:none;min-width:0;padding:0}.embedded .topbar,.embedded footer{display:none}.embedded button:focus-visible,.embedded input:focus-visible,.embedded select:focus-visible{outline:3px solid #68686d;outline-offset:3px}.embedded button{transition:background-color .18s,color .18s}
.embedded .lesson-layout{grid-template-columns:minmax(0,1fr) 288px;gap:24px 28px;padding-top:0;align-items:start}.embedded .heading{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:12px;padding:0}.embedded .heading h1{font-family:inherit;font-size:32px;line-height:1.4;font-weight:600;letter-spacing:-.8px;color:#1d1d1f;grid-row:1}.embedded .heading .subtitle{font-size:15px;line-height:1.7;color:#626268;grid-row:2;grid-column:1}.embedded .heading .driver-selector{display:flex;width:auto;flex-wrap:wrap;gap:3px;margin:0;padding:4px;border-radius:999px;background:#f5f5f7;grid-row:3;grid-column:1/-1;justify-self:start}.embedded .heading .driver-selector button{color:#626268;border:0;border-radius:999px;font-size:12px;min-width:44px;min-height:44px;padding:8px 13px;background:transparent;flex:none}.embedded .heading .driver-selector button[aria-pressed=true]{background:#fff;color:#1d1d1f;box-shadow:0 1px 4px #00000012}
.embedded .viewer:not(.landscape){border:0;border-radius:24px;box-shadow:none;background:#f5f5f7;align-self:start}.embedded .viewer:not(.landscape) .surface{border-radius:24px 24px 0 0}.embedded .viewer:not(.landscape) .playback{height:auto;min-height:76px;padding:16px 18px;gap:10px;background:#f5f5f7;border:0}.embedded .playback .primary{background:#1d1d1f;color:#fff;border-radius:999px;min-height:44px;padding:10px 17px}.embedded .playback .primary:hover{background:#363638}.embedded .playback .icon-btn{color:#626268;min-width:44px;min-height:44px;border-radius:999px}.embedded .playback .icon-btn:hover{background:#eeeef0}.embedded .time{color:#1d1d1f}.embedded .duration{color:#626268}.embedded .speed select{color:#1d1d1f;min-height:44px;padding:8px 6px;background:#fff;border-color:#919196;border-radius:12px}.embedded input{accent-color:#1d1d1f}.embedded .scrubber{min-height:44px}.embedded .viewer:not(.landscape) .overlay-controls{background:#fff;min-height:56px;padding:10px 0;gap:4px 16px}.embedded .overlay-controls label{font-size:13px;min-height:44px;color:#626268}.embedded .overlay-controls input{width:16px;height:16px}.embedded .fullscreen{min-width:44px;min-height:44px}
.embedded .explanation{background:#f5f5f7;border:0;border-radius:24px;padding:24px;display:flex;gap:0;contain:size;overflow:auto;align-self:stretch;justify-content:flex-start;scrollbar-gutter:stable}.embedded .explanation h2{font-size:22px;line-height:1.5;font-weight:600;letter-spacing:-.4px;color:#1d1d1f;margin:20px 0 12px;min-height:0;text-wrap:balance}.embedded .explanation .eyebrow{font-size:12px;color:#626268;letter-spacing:0}.embedded .explanation .caption{font-size:15px;line-height:1.85;color:#626268;margin:0 0 16px;min-height:0}.embedded .explanation .driver-tip{font-size:14px;line-height:1.8;padding:14px;background:#eeeef0;color:#45454b;margin:0 0 16px;min-height:0;border-radius:12px}.embedded .explanation .rule{padding:14px 12px;background:#eeeef0;border-left-color:#919196;align-items:start;border-radius:12px;min-height:0}.embedded .rule-symbol{color:#626268;border-color:#626268}.embedded .rule strong{color:#45454b;font-size:14px}.embedded .explanation .rule p{font-size:14px;line-height:1.8;color:#626268;margin-top:7px}.embedded .explanation .attention{margin-top:24px}.embedded .attention h3{color:#626268;font-size:13px;letter-spacing:0}.embedded .explanation .vehicles{gap:16px}.embedded .explanation .vehicle-row b{font-size:14px;color:#45454b}.embedded .vehicle-row small{color:#626268;font-size:12px}.embedded .explanation .case-note{color:#626268;font-size:13px;line-height:1.8;margin-top:24px;padding-top:0}.embedded .explanation>*{flex-shrink:0}
.embedded .steps-section{padding:0}.embedded .steps-title{flex-wrap:wrap;gap:14px;margin-bottom:16px}.embedded .steps-title h2{font-size:21px;font-weight:600;letter-spacing:-.4px}.embedded .mode-switch{background:#f5f5f7;border-radius:999px;padding:4px}.embedded .mode-switch button{color:#626268;border-radius:999px;min-height:44px;padding:8px 16px;font-size:14px}.embedded .mode-switch button[aria-pressed=true]{color:#1d1d1f}.embedded .steps{gap:12px}.embedded .steps button{min-height:74px;padding:16px 12px;border:1px solid transparent;background:#f5f5f7;border-radius:14px;color:#626268;gap:9px}.embedded .steps button.active{background:#e9e9ed;border-color:#8d8d92;color:#1d1d1f}.embedded .steps button:hover{border-color:#919196}.embedded .steps b{font-size:14px;white-space:normal;line-height:1.6}.embedded .steps small{font-size:12px;color:#626268}.embedded .steps button>span{border-color:#919196}.embedded .steps button.active>span{background:#1d1d1f;color:#fff;border-color:#1d1d1f}.embedded .steps button.completed>span{background:#e1e1e5;color:#45454b;border-color:#d2d2d7}.embedded .step-nav{flex-wrap:wrap;gap:12px;margin-top:16px}.embedded .step-nav button{color:#626268;min-height:44px;border-radius:999px;font-size:14px;padding:10px 16px}.embedded .step-nav>span{display:block;font-size:13px;color:#626268}
@media(max-width:900px){.embedded .lesson-layout{grid-template-columns:1fr;gap:24px}.embedded .heading{grid-column:1;grid-row:1}.embedded .viewer{grid-column:1;grid-row:2}.embedded .steps-section{grid-column:1;grid-row:3}.embedded .explanation{grid-column:1;grid-row:4;contain:none;overflow:visible;scrollbar-gutter:auto}.embedded .heading .driver-selector{grid-row:3;grid-column:1/-1}.embedded .explanation .vehicles{grid-template-columns:1fr 1fr}.embedded .step-nav>span{order:3;width:100%;text-align:center}}
@media(min-width:901px){.embedded .viewer{grid-column:1;grid-row:2}.embedded .explanation{grid-column:2;grid-row:1/3}.embedded .steps-section{grid-column:1/-1;grid-row:3}}
@media(max-width:600px){.embedded .heading h1{font-size:25px;line-height:1.4;letter-spacing:-.6px}.embedded .heading .subtitle{font-size:14px;grid-column:1/-1}.embedded .heading .driver-selector{width:100%;justify-content:space-between;flex-wrap:nowrap}.embedded .heading .driver-selector button{flex:1;min-width:44px;padding:8px 6px}.embedded .viewer:not(.landscape) .playback{display:grid;grid-template-columns:44px 44px minmax(0,1fr) auto;gap:8px;padding:12px 10px}.embedded .viewer:not(.landscape) .play{grid-column:1;grid-row:1;font-size:0;padding:10px}.embedded .viewer:not(.landscape) .icon-btn{grid-column:2;grid-row:1}.embedded .viewer:not(.landscape) .time{grid-column:3;grid-row:1;font-size:12px}.embedded .viewer:not(.landscape) .speed{grid-column:4;grid-row:1}.embedded .viewer:not(.landscape) .scrubber{grid-column:1/4;grid-row:2;width:100%}.embedded .viewer:not(.landscape) .duration{grid-column:4;grid-row:2;font-size:12px;text-align:center}.embedded .speed select{font-size:14px;max-width:none}.embedded .overlay-controls label{font-size:13px}.embedded .scene-chip{left:9px;top:9px;width:175px;min-width:0;max-width:calc(100% - 108px)}.embedded .fullscreen{right:9px;top:9px;padding:7px}.embedded .fullscreen span{font-size:11px}.embedded .scene-status{bottom:9px;left:9px;padding:6px 9px;font-size:11px}.embedded .lamp-caption{font-size:10px;right:9px;bottom:9px;padding:6px}.embedded .explanation h2{font-size:21px}.embedded .explanation .vehicles{grid-template-columns:1fr}.embedded .steps{grid-template-columns:repeat(2,minmax(0,1fr))}.embedded .steps button{flex-direction:row;text-align:left;justify-content:flex-start;min-height:74px;padding:14px;gap:10px}.embedded .steps button:last-child{grid-column:1/-1}.embedded .steps b{font-size:13px}.embedded .steps-title h2{font-size:20px}.embedded .mode-switch button{font-size:13px;padding:8px 14px}.embedded .landscape .scene-chip{width:230px;max-width:none}.embedded .landscape .playback .play{font-size:14px}}
@media(prefers-reduced-motion:reduce){.embedded button{transition:none}}
/* Approved simplified player, 2026-09-18. */
.embedded .lesson-layout{grid-template-columns:minmax(0,1fr) 318px;gap:22px 24px}
.embedded .heading{grid-column:1/-1;grid-row:1;display:flex;align-items:flex-end;justify-content:space-between;gap:24px}
.embedded .heading .driver-selector{padding:5px;border-radius:13px;gap:6px;flex-wrap:nowrap;flex-shrink:0}
.embedded .heading .driver-selector button{display:flex;align-items:center;justify-content:center;gap:6px;border:1px solid transparent;border-radius:9px;font-size:13px;min-height:44px;padding:10px 12px;font-weight:500;white-space:nowrap}
.embedded .heading .driver-selector button svg{width:18px;height:18px;flex:none}
.embedded .heading .driver-selector button[aria-pressed=true]{background:#1d1d1f;color:#fff;font-weight:750;box-shadow:0 2px 5px #0002}
.embedded .viewer{grid-column:1;grid-row:2}.embedded .viewer:not(.landscape){border:1px solid #e5e5e7;border-radius:18px;background:white}.embedded .viewer:not(.landscape) .surface{border-radius:0}
.embedded .viewer:not(.landscape) .playback,.embedded .viewer.landscape .playback{height:56px;min-height:56px;padding:8px 14px;background:white;gap:10px}
.embedded .playback .pause-control{background:none;border:0;min-width:36px;min-height:36px;width:36px;padding:8px;border-radius:7px;color:#1d1d1f}.embedded .playback .pause-control:hover{background:#eeeef0}.embedded .playback .pause-control svg{width:18px;height:18px}.embedded .time,.embedded .duration{font-size:12px}.embedded .scrubber{min-width:20px;min-height:32px}
.embedded .explanation{grid-column:2;grid-row:2/4;border-radius:18px;padding:22px;contain:size;overflow:auto;justify-content:flex-start;gap:0}
.embedded .explanation h2{font-size:20px;margin:18px 0 14px}.embedded .explanation .caption{font-size:14px;line-height:1.8}.embedded .explanation .driver-tip{padding:0;background:none}.embedded .explanation .rule{background:transparent;border:0;border-top:1px solid #dedee1;border-radius:0;padding:17px 0 0;display:block}.embedded .rule-symbol{display:none}.embedded .explanation .rule p{font-size:13px}.embedded .explanation .case-note{font-size:11px;line-height:1.7;margin:20px 0 0}.embedded .explanation .vehicle-row b{font-size:13px}
.embedded .steps-section{grid-column:1;grid-row:3;margin:0;padding:0}.embedded .steps-title h2{font-size:21px}.embedded .step-help{font-size:12px;color:#6e6e73}.embedded .steps{grid-template-columns:repeat(5,minmax(0,1fr));gap:8px}.embedded .steps button{min-width:0;min-height:68px;padding:10px 8px;border-radius:10px;flex-wrap:wrap;gap:6px}.embedded .steps b{font-size:12px;white-space:normal}.embedded .steps small{font-size:10px}.embedded .steps button.active{background:#f5f5f7;border-color:#1d1d1f}.embedded .steps button.active>span{background:#1d1d1f;color:white}
@media(max-width:1100px){.embedded .heading{display:block}.embedded .heading .driver-selector{width:max-content;margin-top:18px}.embedded .lesson-layout{grid-template-columns:minmax(0,1fr) 270px;gap:18px}.embedded .explanation{padding:18px}}
@media(max-width:760px){.embedded .lesson-layout{display:flex;flex-direction:column;gap:18px}.embedded .heading{width:100%;order:0}.embedded .heading h1{font-size:25px}.embedded .heading .subtitle{font-size:13px}.embedded .heading .driver-selector{width:100%;gap:2px;margin-top:17px;padding:4px;border-radius:11px}.embedded .heading .driver-selector button{flex:1;font-size:12px;padding:9px 3px;gap:4px}.embedded .heading .driver-selector button svg{width:16px;height:16px}.embedded .viewer{order:1}.embedded .viewer:not(.landscape){width:100%}.embedded .steps-section{order:2;width:100%}.embedded .explanation{order:3;width:100%;contain:none;overflow:visible;max-height:none;padding:21px;display:flex}.embedded .explanation .caption{font-size:15px}.embedded .explanation .rule p{font-size:14px}.embedded .steps{grid-template-columns:repeat(3,minmax(0,1fr));gap:7px}.embedded .steps button{display:flex;flex-direction:row;flex-wrap:wrap;align-items:center;justify-content:flex-start;text-align:left;min-height:64px;padding:9px 7px}.embedded .steps button:last-child{grid-column:auto}.embedded .steps b{font-size:12px}.embedded .steps small{display:block}.embedded .steps-title h2{font-size:18px}.embedded .step-help{font-size:11px}.embedded .viewer:not(.landscape){border-radius:13px}.embedded .viewer:not(.landscape) .playback{height:48px;min-height:48px;padding:6px 9px;gap:8px}.embedded .scene-chip{width:175px;min-width:175px;max-width:calc(100% - 100px);height:34px;top:8px;left:8px}.embedded .scene-chip .focus-label{font-size:9px}.embedded .scene-chip strong{font-size:10px}.embedded .fullscreen{right:8px;top:8px}.embedded .explanation .vehicles{grid-template-columns:1fr}}
.embedded .heading>div:first-child{display:block;min-width:0;flex:1}.embedded .heading h1{margin:0 0 9px}.embedded .heading .subtitle{margin:0}.embedded .heading .driver-selector{flex:0 0 auto}
@media(max-width:1100px){.embedded .heading .driver-selector{margin-top:18px}}
.embedded .viewer:not(.landscape) .playback,.embedded .viewer.landscape .playback{display:flex;align-items:center}.embedded .playback .scrubber{flex:1;width:60px;min-width:20px}.embedded .playback .time,.embedded .playback .duration{flex:none}.embedded .playback .pause-control{flex:none}

/* Approved shared scene navigation: title, choices, animation. */
.heading,.embedded .heading{display:block;width:100%}
.heading h1,.embedded .heading h1{margin:0 0 9px;line-height:1.4}
.heading nav,.embedded .heading .driver-selector{display:flex;flex-wrap:nowrap;width:max-content;max-width:100%;margin:18px 0 0;padding:4px;gap:2px;border-radius:11px;overflow-x:auto;scrollbar-width:thin;justify-content:flex-start}
.heading nav button,.embedded .heading .driver-selector button{flex:0 0 auto;min-width:0;min-height:44px;padding:8px 11px;font-size:12px;border-radius:8px;gap:5px}
.heading nav svg,.embedded .heading .driver-selector button svg{width:14px;height:14px}
@media(max-width:760px){.heading nav,.embedded .heading .driver-selector{width:100%}.heading nav button,.embedded .heading .driver-selector button{padding:8px 6px}.heading h1{font-size:25px}}

/* Right-of-way explanation: one stable scene chip and no lower-left overlay. */
.scene-chip strong{letter-spacing:0}
.priority-relation{padding:15px;background:#f0f1f2;border:1px solid #e0e2e3;border-radius:12px}
.priority-relation>strong{display:block;color:#36474d;font-size:13px;line-height:1.5;margin-bottom:11px}
.priority-pair{display:grid;grid-template-columns:minmax(0,1fr) 24px minmax(0,1fr);gap:6px;align-items:center}
.priority-pair span{display:flex;flex-direction:column;align-items:center;justify-content:center;min-width:0;min-height:61px;padding:6px 3px;background:#fff;border:1px solid #dde3e4;border-radius:9px;text-align:center}
.priority-pair b{font-size:18px;color:#a73842;line-height:1.2}.priority-pair span:last-child b{color:#44765a}
.priority-pair small{font-size:10px;color:#66777a;line-height:1.4;white-space:nowrap}
.priority-pair em{font-size:16px;font-weight:750;color:#277c79;text-align:center;font-style:normal}
.priority-detail{margin-top:17px;padding-left:12px;border-left:3px solid #368b84}
.priority-detail strong{font-size:13px;color:#286e6b}.priority-detail p{font-size:14px;color:#4f6469;line-height:1.7;margin:7px 0 0}
.priority-foot{margin:auto 0 0;padding-top:22px;color:#63777a;font-size:12px;line-height:1.7}
@media(max-width:760px){.priority-foot{margin-top:16px}.embedded .scene-chip{width:205px;min-width:0;max-width:calc(100% - 112px);height:46px}.embedded .scene-chip strong{font-size:10px;letter-spacing:0}.priority-pair small{white-space:normal}}

/* Keep the full, approved B1 gap wording readable without a second scene overlay. */
.scene-chip{width:300px;height:56px;grid-template-rows:12px 30px}
.scene-chip strong{white-space:normal;text-overflow:clip;display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:2;line-height:15px;font-size:12px;letter-spacing:0}
@media(max-width:760px){.scene-chip,.embedded .scene-chip{width:248px;max-width:calc(100% - 106px);min-width:0;height:54px;grid-template-rows:12px 28px}.scene-chip strong,.embedded .scene-chip strong{font-size:10px;line-height:14px}}

/* BEGIN shared judgment typography */
html:root body :is(.scene-chip,.observation){position:absolute;top:18px;left:20px;width:284px;max-width:calc(100% - 106px);min-width:0;height:58px;min-height:58px;padding:3px 10px;display:grid;grid-template-columns:34px minmax(0,1fr);grid-template-rows:14px auto;gap:3px 8px;align-items:start;align-content:center;border:1px solid #fff;border-radius:8px;background:#fffffff0;color:#647b7c;font-size:12px;font-weight:400;box-shadow:0 2px 10px #25422b10;pointer-events:none}
html:root body .observation>div{display:contents}
html:root body :is(.scene-chip .key-id,.observation>span){grid-column:1;grid-row:1/3;align-self:center;width:34px;height:30px;padding:0;display:grid;place-items:center;border-radius:5px;color:#fff;font-size:15px;font-weight:700;line-height:normal}
html:root body :is(.scene-chip .focus-label,.observation small){grid-column:2;grid-row:1;font-size:10px;line-height:14px;margin:0;align-self:start;color:#647b7c;white-space:nowrap}
html:root body :is(.scene-chip strong,.observation strong){grid-column:2;grid-row:2;font-size:12px;line-height:16px;font-weight:700;margin:0;align-self:start;letter-spacing:0;color:#193b45;white-space:normal;overflow:visible;text-overflow:clip;display:block;-webkit-line-clamp:unset}
@media(max-width:1150px){html:root body :is(.scene-chip,.observation){top:12px;left:12px}}
@media(max-width:760px){html:root body :is(.scene-chip,.observation){top:8px;left:8px;width:248px;max-width:calc(100% - 106px);height:56px;min-height:56px;padding:2px 7px}html:root body :is(.scene-chip strong,.observation strong){font-size:11px}}
/* END shared judgment typography */

.scene-chip{--judgment-base-width:300px}

/* BEGIN shared fullscreen button: single-lane roundabout baseline */
html body button:is(.fullscreen,#wide,#expand){position:absolute;top:12px;right:12px;bottom:auto;left:auto;display:block;box-sizing:border-box;width:auto;height:auto;min-width:0;min-height:36px;margin:0;padding:8px 10px;border:1px solid #fff9;border-radius:8px;background:#ffffffec;color:#1d1d1f;font-family:-apple-system,BlinkMacSystemFont,'Helvetica Neue','PingFang SC','Microsoft YaHei',sans-serif;font-size:12px;font-weight:400;line-height:normal;letter-spacing:normal;white-space:nowrap;box-shadow:none;text-align:center}
html body button:is(.fullscreen,#wide,#expand) span{font:inherit;letter-spacing:inherit;vertical-align:baseline}
html body button.fullscreen svg{display:none}
html body button.fullscreen::before{content:'⛶ '}
@media(max-width:760px){html body button:is(.fullscreen,#wide,#expand){top:8px;right:8px;min-height:32px;padding:5px;font-size:10px}}
/* END shared fullscreen button */

/* BEGIN shared scene page layout: T-junction baseline */
html:root{--lesson-gap:22px;--lesson-column-gap:24px;--lesson-aside-width:318px;--lesson-aside-padding:22px;--lesson-body-size:14px;--lesson-rule-size:13px;--lesson-step-size:21px}
html:root body :is(.lesson,.lesson-layout){grid-template-columns:minmax(0,1fr) var(--lesson-aside-width);gap:var(--lesson-gap) var(--lesson-column-gap);align-items:start;align-content:start}
html:root body .heading{display:block;padding:0;margin:0;width:100%;min-width:0}
html:root body main>.heading{margin-bottom:var(--lesson-gap)}
html:root body .heading h1{font-family:inherit;font-size:32px;line-height:1.4;font-weight:600;letter-spacing:-.8px;margin:0 0 9px;color:#1d1d1f;text-wrap:balance}
html:root body .heading :is(p,.subtitle){font-size:15px;line-height:1.7;color:#626268;margin:0}
html:root body .heading :is(nav,.driver-selector){display:flex;align-items:center;flex-wrap:nowrap;width:max-content;max-width:100%;margin:18px 0 0;padding:4px;gap:2px;background:#f5f5f7;border-radius:11px;overflow-x:auto}
html:root body .heading :is(nav,.driver-selector) button{display:flex;align-items:center;justify-content:center;flex:none;min-height:44px;padding:8px 11px;border:1px solid transparent;border-radius:8px;font-size:12px;font-weight:500;line-height:normal;gap:5px;white-space:nowrap;background:transparent;color:#626268}
html:root body .heading :is(nav,.driver-selector) button[aria-pressed=true]{background:#1d1d1f;color:white;font-weight:750;box-shadow:0 2px 5px #0002}
html:root body .heading :is(nav,.driver-selector) svg{width:14px;height:14px;flex:none}
html:root body :is(aside,.explanation){min-width:0;display:flex;flex-direction:column;gap:0;align-self:stretch;padding:var(--lesson-aside-padding);background:#f5f5f7;border:0;border-radius:18px;contain:size;overflow:auto;scrollbar-gutter:stable;justify-content:flex-start;color:#1d1d1f}
html:root body :is(aside,.explanation)>*{flex-shrink:0}
html:root body :is(aside,.explanation) :is(.panel-top,.panel-meta){min-height:22px;height:auto;display:flex;align-items:center;justify-content:space-between;gap:10px;margin:0;font-size:12px;line-height:1.5;color:#626268}
html:root body :is(aside,.explanation) .eyebrow{margin:0;font-size:12px;line-height:22px;font-weight:700;letter-spacing:0;color:#626268}
html:root body :is(aside,.explanation) h2{font-family:inherit;font-size:20px;line-height:1.5;font-weight:600;letter-spacing:-.4px;margin:18px 0 14px;min-height:0;color:#1d1d1f;text-wrap:balance}
html:root body :is(aside,.explanation) :is(.caption,#body){font-size:var(--lesson-body-size);line-height:1.8;font-weight:400;color:#626268;margin:0 0 16px;min-height:0}
html:root body :is(aside,.explanation) :is(.rule,.lane,.next-check){display:block;background:none;border:0;border-top:1px solid #dedee1;border-radius:0;padding:17px 0 0;margin:0;min-height:0}
html:root body :is(aside,.explanation) :is(.rule,.lane,.next-check) :is(strong,h3){display:block;font-size:14px;line-height:1.5;font-weight:700;color:#45454b;letter-spacing:0;margin:0}
html:root body :is(aside,.explanation) :is(.rule,.lane,.next-check) p{font-size:var(--lesson-rule-size);line-height:1.8;font-weight:400;color:#626268;margin:7px 0 0}
html:root body :is(aside,.explanation) :is(.case-note,.note){font-size:11px;line-height:1.7;font-weight:400;color:#626268;margin:20px 0 0;padding:0}
html:root body :is(aside,.explanation) .attention{margin-top:24px}
html:root body :is(aside,.explanation) .attention h3{font-size:13px;color:#626268;letter-spacing:0;margin:0 0 14px}
html:root body :is(aside,.explanation) .vehicles{display:grid;gap:16px}
html:root body :is(aside,.explanation) .vehicle-row b{font-size:13px;color:#45454b}
html:root body :is(aside,.explanation) .vehicle-row small{font-size:12px;color:#626268;margin-top:3px}
html:root body :is(aside,.explanation) :is(.arrow-legend,.vehicle-legend){font-size:12px;line-height:1.7;color:#626268;margin:20px 0 0}
html:root body :is(aside,.explanation) .arrow-legend+.rule{margin-top:20px}
html:root body :is(aside,.explanation) #sign{width:min(100%,230px);max-width:100%;margin:0 auto 16px}
html:root body :is(aside,.explanation) .when-to-use{margin:0 0 18px}
html:root body :is(aside,.explanation) .when-to-use h3{font-size:14px;line-height:1.5;margin:0 0 7px;color:#45454b}
html:root body :is(aside,.explanation) .when-to-use p{font-size:var(--lesson-body-size);line-height:1.8;color:#626268;margin:0}
html:root body .steps-section{padding:0;margin:0;min-width:0;align-self:start}
html:root body :is(.steps-title,.steps-heading){display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:14px;margin:0 0 16px}
html:root body :is(.steps-title,.steps-heading) h2{font-size:var(--lesson-step-size);line-height:1.4;font-weight:600;letter-spacing:-.4px;margin:0;padding:0;color:#1d1d1f}
html:root body :is(.steps-title,.steps-heading)>span{font-size:12px;line-height:1.5;color:#6e6e73}
html:root body .steps{gap:8px}
html:root body .steps button{display:flex;align-items:center;justify-content:flex-start;flex-direction:row;flex-wrap:wrap;min-width:0;min-height:68px;padding:10px 8px;gap:6px;border:1px solid transparent;border-radius:10px;background:#f5f5f7;font-size:12px;font-weight:550;line-height:1.6;color:#626268;text-align:left}
html:root body .steps button:is(.active,[aria-pressed=true]){background:#f5f5f7;border-color:#1d1d1f;color:#1d1d1f}
html:root body .steps button>span{width:23px;height:23px;flex:0 0 23px;display:grid;place-items:center;border:1px solid #919196;border-radius:50%;font-size:12px;font-weight:400;line-height:normal}
html:root body .steps button:is(.active,[aria-pressed=true])>span{background:#1d1d1f;color:white;border-color:#1d1d1f}
html:root body .steps b{font-size:12px;font-weight:550;line-height:1.6;white-space:normal}
html:root body .steps small{font-size:10px;color:#626268}
html:root body .step-nav{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;margin-top:16px;gap:12px}
html:root body .step-nav button{display:flex;align-items:center;gap:8px;background:white;color:#626268;min-height:44px;padding:10px 16px;border:1px solid #d2d2d7;border-radius:999px;font-size:14px}
html:root body .step-nav>span{font-size:13px;line-height:1.5;color:#626268}
html:root body .mode-switch{display:flex;background:#f5f5f7;border-radius:999px;padding:4px}
html:root body .mode-switch button{min-height:44px;padding:8px 16px;font-size:14px;color:#626268;border:0;border-radius:999px;background:none}
html:root body .mode-switch button[aria-pressed=true]{background:white;color:#1d1d1f;box-shadow:0 1px 4px #00000012}
html:root.embedded body .sources{display:none}
@media(max-width:1100px){html:root{--lesson-gap:18px;--lesson-column-gap:18px;--lesson-aside-width:270px;--lesson-aside-padding:18px}}
@media(max-width:760px){
html:root{--lesson-aside-padding:21px;--lesson-body-size:15px;--lesson-rule-size:14px;--lesson-step-size:18px}
html:root body :is(.lesson,.lesson-layout){display:flex;flex-direction:column;gap:18px}
html:root body .heading h1{font-size:25px;letter-spacing:-.8px}
html:root body .heading :is(p,.subtitle){font-size:13px}
html:root body .heading :is(nav,.driver-selector){width:100%}
html:root body .heading :is(nav,.driver-selector) button{padding:8px 6px}
html:root body :is(aside,.explanation){width:100%;order:3;contain:none;overflow:visible;scrollbar-gutter:auto;max-height:none}
html:root body :is(aside,.explanation) .vehicles{grid-template-columns:1fr}
html:root body .steps{grid-template-columns:repeat(3,minmax(0,1fr));gap:7px}
html:root body .steps button{min-height:64px;padding:9px 7px}
html:root body .steps button:last-child{grid-column:auto}
html:root body :is(.steps-title,.steps-heading)>span{font-size:11px}
html:root body .mode-switch button{font-size:13px;padding:8px 14px}
html:root body .step-nav>span{display:block;order:3;width:100%;text-align:center}
}
/* The T-junction exposes route selection and step cards, without duplicate mode/navigation controls. */
html:root body :is(.mode-switch,.step-nav,.scene-status,.status,.lamp-caption,.lane-hint){display:none!important}
html:root body :is(.steps-title,.steps-heading)::after{content:'点击观看这一段';font-size:12px;line-height:1.5;font-weight:400;letter-spacing:0;color:#6e6e73}
html:root body :is(.steps-title,.steps-heading)>span{display:none}
html:root body .steps small{display:block;margin-left:auto;font-size:10px;line-height:1.6}
html:root body .steps button>span{text-align:center}
html:root body .steps button:hover{border-color:#919196}
html:root body :is(.steps button,.heading button):focus-visible{outline:3px solid #68686d;outline-offset:3px}
@media(max-width:760px){html:root body :is(.steps-title,.steps-heading)::after{font-size:11px}}
html:root body .steps button:has(~button:is(.active,[aria-pressed=true]))>span{background:#e1e1e5;color:#45454b;border-color:#d2d2d7}
/* Approved A1: stable number/time row, full-width title below. */
html:root body .steps{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:8px;align-items:stretch}
html:root body .steps button{display:grid;grid-template-columns:23px minmax(0,1fr);grid-template-rows:23px auto;align-content:start;align-items:start;justify-content:normal;min-height:106px;padding:13px 12px;gap:12px 6px}
html:root body .steps button>span{grid-column:1;grid-row:1;margin:0}
html:root body .steps button>small{grid-column:2;grid-row:1;align-self:center;justify-self:end;margin:0;font-size:11px;font-weight:400;line-height:1.6;white-space:nowrap;font-variant-numeric:tabular-nums;color:#6e6e73}
html:root body .steps button>b{grid-column:1/-1;grid-row:2;display:block;min-width:0;min-height:43px;margin:0;font-size:13px;line-height:1.65;font-weight:600;white-space:normal;overflow-wrap:anywhere;overflow:visible;text-overflow:clip}
html:root body .steps button:hover{background:#eeeef0}
@media(max-width:760px){html:root body .steps{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}html:root body .steps button{padding:11px 10px;min-height:98px}html:root body .steps button>b{font-size:12px;min-height:40px}}
/* END shared scene page layout */

/* BEGIN shared player controls: T-junction baseline */
html:root body:not(.wide) :is(.lesson-layout>.viewer,#player):not(.landscape){border:1px solid #e5e5e7;border-radius:18px;overflow:hidden;background:white;box-shadow:none;align-self:start}
html:root body :is(.playback,.controls){display:flex;align-items:center;flex-wrap:nowrap;flex:none;height:56px;min-height:56px;padding:8px 14px;gap:10px;background:white;border:0;box-sizing:border-box}
html:root body :is(.playback,.controls) button:is(#play,#replay,.pause-control,.play,.icon-btn){display:grid;place-items:center;flex:0 0 36px;width:36px;min-width:36px;height:36px;min-height:36px;padding:8px;margin:0;border:0;border-radius:7px;background:transparent;color:#1d1d1f;gap:0;font-size:0;line-height:1;box-shadow:none;transition:background-color .18s,color .18s}
html:root body :is(.playback,.controls) button:is(#play,#replay,.pause-control,.play,.icon-btn):hover{background:#eeeef0}
html:root body :is(.playback,.controls) button:is(#play,#replay,.pause-control,.play,.icon-btn):active{background:#e1e1e5}
html:root body :is(.playback,.controls) :is(button,input,select):focus-visible{outline:3px solid #68686d;outline-offset:3px}
html:root body :is(.playback,.controls) button:is(#play,.pause-control,.play) svg{width:18px;height:18px;fill:currentColor;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
html:root body :is(.playback,.controls) :is(.time,.duration,#clock,#duration){flex:none;font-family:inherit;font-size:12px;font-weight:400;line-height:normal;font-variant-numeric:tabular-nums;color:#1d1d1f;white-space:nowrap;margin:0}
html:root body :is(.playback,.controls) :is(.duration,#duration){color:#626268}
html:root body :is(.playback,.controls) input[type=range]{flex:1;width:60px;min-width:20px;height:32px;min-height:32px;margin:2px;padding:0;accent-color:#1d1d1f;cursor:pointer}
html:root body :is(.playback,.controls) :is(select,.speed,#replay,button[aria-label="重播"]){display:none!important}
@media(max-width:760px){
html:root body:not(.wide) :is(.lesson-layout>.viewer,#player):not(.landscape){border-radius:13px}
html:root body :is(.playback,.controls){height:48px;min-height:48px;padding:6px 9px;gap:8px}
}
@media(max-width:360px){html:root body :is(.playback,.controls){gap:6px;padding:6px 7px}}
@media(prefers-reduced-motion:reduce){html:root body :is(.playback,.controls) button{transition:none}}
/* END shared player controls */