/*! tailwindcss v4.2.1 | MIT License | https://tailwindcss.com */
@layer theme{:root,:host{--font-sans:ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";--font-mono:ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;--spacing:.25rem;--default-font-family:var(--font-sans);--default-mono-font-family:var(--font-mono)}}@layer base{*,:after,:before,::backdrop{box-sizing:border-box;border:0 solid;margin:0;padding:0}::file-selector-button{box-sizing:border-box;border:0 solid;margin:0;padding:0}html,:host{-webkit-text-size-adjust:100%;tab-size:4;line-height:1.5;font-family:var(--default-font-family,ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji");font-feature-settings:var(--default-font-feature-settings,normal);font-variation-settings:var(--default-font-variation-settings,normal);-webkit-tap-highlight-color:transparent}hr{height:0;color:inherit;border-top-width:1px}abbr:where([title]){-webkit-text-decoration:underline dotted;text-decoration:underline dotted}h1,h2,h3,h4,h5,h6{font-size:inherit;font-weight:inherit}a{color:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;text-decoration:inherit}b,strong{font-weight:bolder}code,kbd,samp,pre{font-family:var(--default-mono-font-family,ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace);font-feature-settings:var(--default-mono-font-feature-settings,normal);font-variation-settings:var(--default-mono-font-variation-settings,normal);font-size:1em}small{font-size:80%}sub,sup{vertical-align:baseline;font-size:75%;line-height:0;position:relative}sub{bottom:-.25em}sup{top:-.5em}table{text-indent:0;border-color:inherit;border-collapse:collapse}:-moz-focusring{outline:auto}progress{vertical-align:baseline}summary{display:list-item}ol,ul,menu{list-style:none}img,svg,video,canvas,audio,iframe,embed,object{vertical-align:middle;display:block}img,video{max-width:100%;height:auto}button,input,select,optgroup,textarea{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}::file-selector-button{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}:where(select:is([multiple],[size])) optgroup{font-weight:bolder}:where(select:is([multiple],[size])) optgroup option{padding-inline-start:20px}::file-selector-button{margin-inline-end:4px}::placeholder{opacity:1}@supports (not ((-webkit-appearance:-apple-pay-button))) or (contain-intrinsic-size:1px){::placeholder{color:currentColor}@supports (color:color-mix(in lab, red, red)){::placeholder{color:color-mix(in oklab, currentcolor 50%, transparent)}}}textarea{resize:vertical}::-webkit-search-decoration{-webkit-appearance:none}::-webkit-date-and-time-value{min-height:1lh;text-align:inherit}::-webkit-datetime-edit{display:inline-flex}::-webkit-datetime-edit-fields-wrapper{padding:0}::-webkit-datetime-edit{padding-block:0}::-webkit-datetime-edit-year-field{padding-block:0}::-webkit-datetime-edit-month-field{padding-block:0}::-webkit-datetime-edit-day-field{padding-block:0}::-webkit-datetime-edit-hour-field{padding-block:0}::-webkit-datetime-edit-minute-field{padding-block:0}::-webkit-datetime-edit-second-field{padding-block:0}::-webkit-datetime-edit-millisecond-field{padding-block:0}::-webkit-datetime-edit-meridiem-field{padding-block:0}::-webkit-calendar-picker-indicator{line-height:1}:-moz-ui-invalid{box-shadow:none}button,input:where([type=button],[type=reset],[type=submit]){appearance:button}::file-selector-button{appearance:button}::-webkit-inner-spin-button{height:auto}::-webkit-outer-spin-button{height:auto}[hidden]:where(:not([hidden=until-found])){display:none!important}}@layer components;@layer utilities{.fixed{position:fixed}.start{inset-inline-start:var(--spacing)}.table{display:table}.rounded{border-radius:.25rem}}:root{--ink:#17324d;--muted:#5e7185;--coral:#ff6b5f;--orange:#ff9f43;--teal:#21b8a6;--blue:#4388e8;--cream:#fff8e9}*{box-sizing:border-box}html{background:#dff4ff;min-width:320px}body{min-height:100vh;color:var(--ink);background:radial-gradient(circle at 12% 8%,#fffffff2,#0000 27%),linear-gradient(160deg,#d9f5ff 0%,#edfaff 48%,#fff7df 100%);margin:0;font-family:Microsoft YaHei,PingFang SC,Hiragino Sans GB,Arial,sans-serif}button,input{font:inherit}button{-webkit-tap-highlight-color:transparent}.lesson-shell{width:min(1520px,100%);min-height:100vh;margin:0 auto;padding:14px clamp(10px,2vw,28px) 24px}.question-card{-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);background:#ffffffe0;border:2px solid #ffffffd1;border-radius:26px;grid-template-columns:minmax(230px,.75fr) minmax(520px,2.2fr);align-items:center;gap:clamp(18px,3vw,46px);margin-bottom:12px;padding:15px clamp(18px,2.5vw,36px);display:grid;overflow:hidden;box-shadow:0 13px 35px #30719129}.title-block{position:relative}.title-block:after{content:"";background:linear-gradient(var(--coral), #ffd369);border-radius:99px;width:3px;height:calc(100% - 16px);position:absolute;top:8px;right:-24px}.lesson-kicker,.modal-kicker{color:#a54524;letter-spacing:.04em;background:#fff0d6;border-radius:999px;align-items:center;padding:5px 11px;font-size:13px;font-weight:800;display:inline-flex}h1,h2,p{margin-top:0}h1{color:#153b5a;letter-spacing:-.04em;margin:5px 0 0;font-size:clamp(26px,2.4vw,42px);line-height:1.08}.question-text{color:#38556d;margin-bottom:0;font-size:clamp(15px,1.18vw,19px);font-weight:650;line-height:1.75}.question-text strong{color:#e35742;font-weight:900}.scene-card{background:#fff;border:3px solid #ffffffeb;border-radius:30px;overflow:hidden;box-shadow:0 20px 55px #265b773b}.scene-stage{isolation:isolate;background:#8ed9ff;height:clamp(390px,56vh,590px);min-height:390px;position:relative;overflow:hidden}.campus-background{z-index:-3;object-fit:cover;object-position:center bottom;-webkit-user-select:none;user-select:none;width:104%;max-width:none;height:104%;transform:translateX(var(--scene-shift)) scale(1.01);position:absolute;top:-2%;bottom:-2%;left:-2%}.scene-stage:after{content:"";z-index:-1;pointer-events:none;background:linear-gradient(#17496905 54%,#2a4c311f 100%),linear-gradient(90deg,#ffffff0d,#0000 26% 72%,#fff8d314);position:absolute;inset:0}.sun-glow{z-index:-2;pointer-events:none;background:radial-gradient(circle,#fff5b8a6,#0000 67%);border-radius:50%;width:340px;height:340px;animation:4s ease-in-out infinite breathe;position:absolute;top:-120px;right:5%}.petals{z-index:1;pointer-events:none;position:absolute;inset:0;overflow:hidden}.petals span{top:-30px;left:var(--petal-left);opacity:.76;width:12px;height:8px;animation:petal-fall var(--petal-duration) linear var(--petal-delay) infinite;background:#ff9fc2;border-radius:80% 10%;position:absolute}.scene-toolbar{z-index:12;gap:8px;display:flex;position:absolute;top:14px;right:14px}.round-tool,.icon-tool{color:#274b67;cursor:pointer;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);background:#ffffffe0;border:1px solid #ffffffe6;box-shadow:0 7px 20px #1d557129}.round-tool{border-radius:999px;min-height:42px;padding:0 15px;font-size:14px;font-weight:800}.icon-tool{border-radius:50%;width:42px;height:42px;font-size:19px}.round-tool:hover,.icon-tool:hover,.round-tool:focus-visible,.icon-tool:focus-visible{background:#fff;outline:none;transform:translateY(-1px)}.learning-panel{z-index:10;-webkit-backdrop-filter:blur(13px);backdrop-filter:blur(13px);background:#ffffffde;border:1px solid #ffffffdb;border-radius:22px;width:min(392px,100% - 190px);padding:12px;animation:.26s ease-out panel-in;position:absolute;top:14px;left:14px;box-shadow:0 12px 30px #1d59772b}.metric-time{color:#fff;background:linear-gradient(120deg,#4b86e8,#6b6ce8);border-radius:14px;justify-content:space-between;align-items:baseline;margin-bottom:8px;padding:8px 12px;display:flex}.metric-time span{font-size:13px;font-weight:750}.metric-time strong{font-size:21px}.metric-grid{grid-template-columns:repeat(2,1fr);gap:7px;display:grid}.metric{min-width:0}.metric-grid .metric{border-radius:13px;flex-direction:column;padding:8px 10px;display:flex}.metric-grid span{color:#62778b;font-size:11px;font-weight:700}.metric-grid strong{color:#23435c;margin-top:2px;font-size:15px}.teacher-metric{background:#fff0eb}.xiaoman-metric{background:#e9fbf7}.gap-metric{background:#fff6d7}.speed-gap-metric{background:#eef0ff}.compact-gap-pill{z-index:10;color:#2e526b;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);background:#ffffffe6;border:1px solid #fff;border-radius:999px;align-items:center;gap:9px;padding:9px 14px;font-size:14px;display:flex;position:absolute;top:16px;left:16px;box-shadow:0 9px 24px #1d597729}.compact-gap-pill span{color:#5c778a;font-size:11px;font-weight:850}.compact-gap-pill strong{color:#e35742;font-size:16px}.chase-commentary{z-index:9;color:#23485f;text-align:center;-webkit-backdrop-filter:blur(9px);backdrop-filter:blur(9px);background:#fffce0eb;border:2px solid #ffffffeb;border-radius:999px;align-items:center;gap:8px;max-width:min(320px,50% - 170px);padding:9px 15px;font-size:clamp(12px,1.2vw,16px);font-weight:900;display:flex;position:absolute;top:14px;right:72px;box-shadow:0 8px 20px #25546529}.checkpoint-track{z-index:8;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);background:#20546f73;border:1px solid #ffffffc7;border-radius:999px;justify-content:center;align-items:center;gap:clamp(12px,3vw,38px);padding:7px 18px;display:flex;position:absolute;top:15px;left:50%;transform:translate(-50%);box-shadow:0 7px 18px #163f5421}.checkpoint-track:before{content:"";z-index:-1;background:#ffffff7a;border-radius:99px;height:3px;position:absolute;left:18px;right:18px}.checkpoint-track span{color:#667d8d;background:#edf4f5;border:2px solid #fff;border-radius:50%;place-items:center;width:30px;height:30px;font-size:19px;transition:transform .22s,color .22s,background .22s;display:grid;box-shadow:0 3px 8px #1a41542b}.checkpoint-track span.is-passed{color:#a8640c;background:#ffe35e;transform:scale(1.12)rotate(8deg)}.checkpoint-track b{color:#fff;background:#21475ba8;border-radius:99px;min-width:max-content;padding:2px 6px;font-size:9px;position:absolute;top:35px}.home-marker{z-index:2;opacity:1;pointer-events:none;filter:drop-shadow(0 4px 4px #28493738);flex-direction:column;align-items:center;gap:1px;display:flex;position:absolute}.home-marker span{font-size:clamp(22px,2.4vw,36px)}.home-marker b{color:#3b5367;background:#ffffffdb;border-radius:999px;padding:4px 9px;font-size:11px}.teacher-home{bottom:25.5%;left:var(--teacher-start);transform:translate(-50%)}.xiaoman-home{bottom:6.5%;left:var(--xiaoman-start);transform:translate(-50%)}.lane-guide,.journey-line{z-index:4;pointer-events:none;border-radius:999px;height:5px;position:absolute}.lane-guide{right:calc(100% - var(--track-end));background:repeating-linear-gradient(90deg,#ffffffd1 0 12px,#2b585b40 12px 18px);border:1px solid #ffffffc7;box-shadow:0 2px 5px #2046462e}.teacher-lane-guide{bottom:25.5%;left:var(--teacher-start)}.xiaoman-lane-guide{bottom:6.5%;left:var(--xiaoman-start)}.journey-line{transition:width 45ms linear}.journey-line:after{content:"";background:inherit;border:3px solid #fff;border-radius:50%;width:12px;height:12px;position:absolute;top:50%;right:-6px;transform:translateY(-50%);box-shadow:0 3px 8px #2549543d}.teacher-journey{bottom:25.5%;left:var(--teacher-start);width:var(--teacher-trail-width);background:linear-gradient(90deg,#ffae55,#f06454)}.xiaoman-journey{bottom:6.5%;left:var(--xiaoman-start);width:var(--xiaoman-trail-width);background:linear-gradient(90deg,#64dfcc,#16a992)}.character{z-index:7;cursor:grab;touch-action:none;-webkit-user-select:none;user-select:none;will-change:left;justify-content:center;align-items:center;transition:left 45ms linear;display:flex;position:absolute;transform:translate(-50%)}.character:active{cursor:grabbing}.character:focus-visible{outline-offset:4px;filter:drop-shadow(0 0 .5rem #4388e8);border-radius:28px;outline:4px solid #fff}.character img{pointer-events:none;filter:drop-shadow(0 10px 8px #1c302542);width:100%;height:auto;display:block}.teacher{bottom:25.5%;left:var(--teacher-left);width:clamp(72px,7vw,106px)}.xiaoman{bottom:6.5%;left:var(--xiaoman-left);width:clamp(66px,6.3vw,96px)}.scene-stage.is-dragging .character,.scene-stage.is-dragging .distance-ruler,.scene-stage.is-dragging .journey-line{transition:none}.character.is-walking img{animation:.26s ease-in-out infinite alternate walking-bob}.character.is-walking:before{content:"";z-index:-1;background:#fff5cec7;border-radius:50%;width:9px;height:9px;animation:.6s ease-out infinite dust-puff;position:absolute;bottom:4%;right:62%;box-shadow:13px 3px #fff5ce85,24px -2px #fff5ce5c}.character-label{z-index:2;color:#fff;border:2px solid #ffffffe6;border-radius:999px;align-items:center;gap:6px;min-width:max-content;padding:6px 9px;font-size:clamp(10px,1vw,13px);display:flex;position:absolute;top:-16px;left:50%;transform:translate(-50%,-100%);box-shadow:0 6px 15px #21435633}.character-label span{background:#fff3;border-radius:999px;padding:2px 5px}.teacher-label{background:linear-gradient(120deg,#f06454,#ff914d)}.xiaoman-label{background:linear-gradient(120deg,#11a994,#36c5a8)}.drag-hint{color:#27445b;background:#ffffffd9;border-radius:999px;min-width:max-content;padding:3px 8px;font-size:10px;font-weight:800;animation:1.8s ease-in-out infinite hint-pulse;position:absolute;bottom:-18px;left:50%;transform:translate(-50%);box-shadow:0 4px 12px #254b5d24}.position-dot{z-index:3;border:3px solid #fff;border-radius:50%;width:13px;height:13px;position:absolute;bottom:-3px;left:50%;transform:translate(-50%);box-shadow:0 3px 8px #1e444d47}.teacher .position-dot{background:#f06454}.xiaoman .position-dot{background:#19ac98}.distance-ruler{z-index:5;left:var(--distance-left);width:var(--distance-width);pointer-events:none;min-width:10px;height:26px;transition:left 45ms linear,width 45ms linear;position:absolute;bottom:16.1%}.ruler-line{background:repeating-linear-gradient(90deg,#ffdf4f 0 12px,#fff 12px 18px);border-radius:999px;width:100%;height:4px;position:absolute;top:13px;left:0;box-shadow:0 2px 5px #41442a47}.ruler-start,.ruler-end{background:#fff;border-radius:4px;width:4px;height:14px;position:absolute;top:8px;box-shadow:0 1px 4px #2c44474d}.ruler-start{left:0}.ruler-end{right:0}.distance-ruler b{color:#945018;background:#ffeb77;border:2px solid #fff;border-radius:999px;min-width:max-content;padding:4px 8px;font-size:clamp(11px,1vw,14px);position:absolute;top:-25px;left:50%;transform:translate(-50%);box-shadow:0 5px 13px #4845242e}.distance-ruler.is-caught{opacity:0}.caught-bubble{z-index:11;left:var(--teacher-left);color:#fff;background:linear-gradient(120deg,#ff6d55,#ff9e42);border:3px solid #fff;border-radius:20px 20px 20px 5px;padding:12px 19px;font-size:clamp(18px,2vw,28px);font-weight:950;animation:.52s cubic-bezier(.2,1.5,.5,1) caught-pop;position:absolute;bottom:62%;transform:translate(-50%);box-shadow:0 12px 25px #b14f2b47}.learning-dock{background:linear-gradient(90deg,#effaff,#fffaf0);border-top:1px solid #d8eaf0;grid-template-columns:auto minmax(0,1fr);align-items:stretch;gap:12px;min-height:78px;padding:9px 14px;display:grid}.learning-dock.is-collapsed{align-items:center;min-height:48px}.dock-actions{flex-direction:column;gap:7px;display:flex}.learning-dock>p{color:#526d82;align-self:center;margin:0;font-size:13px;font-weight:800}.data-toggle,.speed-lab-toggle{color:#315e75;cursor:pointer;background:#ffffffe0;border:2px solid #c9e4ec;border-radius:15px;min-width:105px;min-height:30px;padding:0 12px;font-size:13px;font-weight:900}.data-toggle:hover,.data-toggle:focus-visible,.speed-lab-toggle:hover,.speed-lab-toggle:focus-visible{background:#fff;border-color:#6bb7ca;outline:none}.speed-lab-toggle{color:#7b5c12;background:#fffae0eb;border-color:#ead89e}.speed-lab-toggle.is-active{color:#604500;background:#fff1a8;border-color:#ffc84a;box-shadow:0 5px 14px #cd981c33}.speed-lab{background:radial-gradient(circle at 8% 10%,#ffe07161,#0000 28%),linear-gradient(120deg,#fffdf3,#f0fbff);border:2px solid #f7c23d8c;border-radius:17px;grid-column:1/-1;grid-template-columns:minmax(170px,1.1fr) repeat(2,minmax(135px,.75fr)) minmax(190px,1fr);align-items:center;gap:10px;padding:12px 14px;display:grid;box-shadow:inset 0 1px #fff}.speed-lab-title{color:#2c536a;flex-direction:column;display:flex}.speed-lab-title strong{font-size:16px}.speed-lab-title span{color:#718696;margin-top:2px;font-size:11px;font-weight:750}.speed-lab label{color:#38596e;grid-template-columns:auto minmax(60px,1fr) auto;align-items:center;gap:6px;font-size:12px;font-weight:900;display:grid}.speed-lab select{color:#23435c;cursor:pointer;background:#fff;border:2px solid #b8dce5;border-radius:12px;min-height:38px;padding:0 28px 0 10px;font-size:15px;font-weight:900}.speed-lab label b{color:#6c8190;white-space:nowrap;font-size:11px}.speed-preview{color:#177260;text-align:center;background:#dff9ef;border-radius:12px;padding:9px 11px;font-size:12px;font-weight:900}.speed-preview.is-invalid{color:#a44a3b;background:#fff0eb}.speed-lab-buttons{grid-column:1/-1;justify-content:flex-end;gap:7px;display:flex}.speed-lab-buttons button{color:#fff;cursor:pointer;white-space:nowrap;background:linear-gradient(120deg,#19bca4,#458df1);border:0;border-radius:12px;min-height:38px;padding:0 12px;font-size:12px;font-weight:900}.speed-lab-buttons button:last-child{color:#476276;background:#eaf2f5}.speed-lab-buttons button:hover,.speed-lab-buttons button:focus-visible{outline:none;transform:translateY(-1px);box-shadow:0 6px 15px #2d7b9733}.speed-lab-buttons button:disabled{cursor:not-allowed;opacity:.45}.metric-strip{grid-template-columns:repeat(5,minmax(108px,1fr));gap:8px;display:grid}.metric-strip .metric{border-radius:13px;flex-direction:column;justify-content:center;min-width:0;margin:0;padding:7px 11px;display:flex}.metric-strip .metric span{color:#60788a;text-overflow:ellipsis;white-space:nowrap;font-size:10px;font-weight:750;overflow:hidden}.metric-strip .metric strong{color:#23435c;white-space:nowrap;margin-top:2px;font-size:clamp(13px,1.25vw,18px)}.metric-strip .metric-time,.metric-strip .metric-time span,.metric-strip .metric-time strong{color:#fff}.control-deck{background:linear-gradient(#fff 0%,#f8fdff 100%);border-top:1px solid #dceef3;grid-template-columns:auto minmax(260px,1fr) auto;align-items:center;gap:18px;min-height:92px;padding:13px clamp(14px,2vw,28px);display:grid}.control-buttons{gap:8px;display:flex}.primary-control,.secondary-control,.step-control,.submit-answer,.play-again{cursor:pointer;border:0;border-radius:15px;min-height:46px;font-weight:900;transition:transform .15s,box-shadow .15s,opacity .15s}.primary-control{color:#fff;background:linear-gradient(120deg,#ff6d59,#ff9f43);min-width:112px;padding:0 18px;box-shadow:0 8px 17px #e7664247}.secondary-control{color:#4e6880;background:#eaf3f7;padding:0 16px}.step-control{color:#28677e;background:#ddf5fa;min-width:58px;padding:0 10px}.step-control:disabled{opacity:.38;cursor:not-allowed}.primary-control:hover:not(:disabled),.secondary-control:hover,.step-control:hover:not(:disabled),.submit-answer:hover,.play-again:hover{transform:translateY(-2px)}.primary-control:disabled{opacity:.45;cursor:not-allowed}.time-scrubber{color:#567086;grid-template-columns:auto 1fr auto;align-items:center;gap:10px;font-size:12px;font-weight:800;display:grid}.time-scrubber input{accent-color:#ff714e;cursor:ew-resize;width:100%}.control-tip{color:#60788b;max-width:230px;margin:0;font-size:12px;font-weight:700;line-height:1.45}.modal-backdrop{z-index:50;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);background:#14334a94;place-items:center;padding:18px;animation:.22s ease-out backdrop-in;display:grid;position:fixed;inset:0}.quiz-card,.success-card{z-index:2;text-align:center;background:linear-gradient(160deg,#fff 0%,#fffaf0 100%);border:4px solid #fffffff2;border-radius:32px;width:min(650px,100%);padding:clamp(25px,4vw,44px);animation:.42s cubic-bezier(.2,1.35,.4,1) modal-pop;position:relative;box-shadow:0 28px 80px #112c3f59}.modal-close{z-index:4;color:#527086;cursor:pointer;background:#fffffff0;border:2px solid #d9e7ed;border-radius:50%;place-items:center;width:42px;height:42px;padding:0;font-size:29px;font-weight:500;line-height:1;transition:transform .15s,color .15s,border-color .15s;display:grid;position:absolute;top:15px;right:15px;box-shadow:0 6px 16px #21465b1f}.modal-close:hover,.modal-close:focus-visible{color:#d94f3f;border-color:#ff9d85;outline:none;transform:rotate(7deg)scale(1.06)}.modal-mascot{background:#ffdf68;border:4px solid #fff;border-radius:50%;place-items:center;width:66px;height:66px;margin:-59px auto 10px;font-size:34px;display:grid;box-shadow:0 8px 20px #825e1c3d}.quiz-card h2,.success-card h2{color:#183d59;margin:9px 0 8px;font-size:clamp(25px,4vw,38px)}.quiz-card>p,.success-card>p{color:#5d7182;font-size:15px;line-height:1.65}.formula-row{color:#28465e;flex-wrap:wrap;justify-content:center;align-items:center;gap:7px;margin:22px 0 16px;font-size:clamp(18px,3vw,26px);font-weight:900;display:flex}.formula-input{color:#163c58;text-align:center;background:#fff;border:3px solid #cfe2ea;border-radius:13px;outline:none;width:clamp(54px,9vw,78px);height:54px;font-size:22px;font-weight:900;transition:border-color .16s,transform .16s,background .16s}.formula-input:focus{border-color:#4f8de6;box-shadow:0 0 0 4px #4f8de626}.formula-input.is-wrong{background:#fff0ed;border-color:#f05f52;animation:.3s ease-in-out shake}.formula-unit{white-space:nowrap}.wrong-hint{color:#a54634;background:#fff1ed;border:2px solid #ffd1c8;border-radius:14px;margin:7px 0 15px;padding:12px 16px;font-size:14px}.quiz-actions{justify-content:center;align-items:center;gap:10px;display:flex}.back-to-scene{color:#4b697e;cursor:pointer;background:#f5fafc;border:2px solid #cfe0e8;border-radius:15px;min-width:150px;min-height:46px;padding:0 22px;font-weight:900;transition:transform .15s,border-color .15s,background .15s}.back-to-scene:hover,.back-to-scene:focus-visible{background:#edf9fd;border-color:#7eb7cf;outline:none;transform:translateY(-2px)}.submit-answer,.play-again{color:#fff;background:linear-gradient(120deg,#29b7a2,#4a88e9);min-width:180px;padding:0 28px;box-shadow:0 10px 22px #2f8a9f45}.success-backdrop{background:#0e2a41b8;overflow:hidden}.success-card{overflow:hidden}.success-card:before{content:"";background:#ffd6532e;border-radius:50%;width:220px;height:220px;position:absolute;top:-90px;left:-90px}.success-stars{letter-spacing:6px;margin-bottom:7px;font-size:36px;animation:.9s ease-in-out infinite alternate stars-bounce}.final-equation{color:#a54e24;background:#fff4cc;border:3px dashed #ffb24c;border-radius:19px;margin:22px auto 16px;padding:17px 18px;font-size:clamp(21px,3.4vw,31px);font-weight:950}.fireworks{z-index:1;pointer-events:none;position:absolute;inset:0}.firework-burst{width:0;height:0;position:absolute}.firework-burst span{background:var(--burst-color);width:8px;height:8px;box-shadow:0 0 8px var(--burst-color);animation:firework-explode 1.75s ease-out var(--burst-delay) infinite;border-radius:50%;position:absolute}@keyframes walking-bob{0%{transform:translateY(1px)rotate(-.35deg)}to{transform:translateY(-3px)rotate(.45deg)}}@keyframes dust-puff{0%{opacity:.85;transform:translate(8px)scale(.55)}to{opacity:0;transform:translate(-30px,-9px)scale(1.5)}}@keyframes petal-fall{0%{opacity:0;transform:translateY(-20px)rotate(0)}12%{opacity:.8}to{opacity:0;transform:translate(110px,650px)rotate(520deg)}}@keyframes breathe{50%{opacity:.72;transform:scale(1.12)}}@keyframes panel-in{0%{opacity:0;transform:translateY(-8px)}}@keyframes hint-pulse{50%{transform:translate(-50%)translateY(-2px);box-shadow:0 7px 16px #254b5d33}}@keyframes caught-pop{0%{opacity:0;transform:translate(-50%)scale(.2)rotate(-8deg)}}@keyframes backdrop-in{0%{opacity:0}}@keyframes modal-pop{0%{opacity:0;transform:translateY(22px)scale(.78)}}@keyframes shake{25%{transform:translate(-5px)}50%{transform:translate(5px)}75%{transform:translate(-3px)}}@keyframes stars-bounce{to{transform:translateY(-7px)rotate(2deg)}}@keyframes firework-explode{0%{opacity:0;transform:rotate(var(--ray-angle)) translateX(0) scale(.2)}14%{opacity:1}72%{opacity:1;transform:rotate(var(--ray-angle)) translateX(var(--ray-distance)) scale(1)}to{opacity:0;transform:rotate(var(--ray-angle)) translateX(calc(var(--ray-distance) * 1.2)) scale(.35)}}@media (width<=900px){.lesson-shell{padding:9px 8px 18px}.question-card{border-radius:21px;grid-template-columns:1fr;gap:7px}.title-block:after{display:none}.question-text{line-height:1.55}.scene-card{border-radius:23px}.scene-stage{height:clamp(390px,56vh,535px)}.chase-commentary{max-width:calc(100% - 30px);top:72px;left:50%;right:auto;transform:translate(-50%)}.learning-panel{width:min(350px,100% - 150px)}.control-deck{grid-template-columns:1fr;gap:10px}.control-buttons{justify-content:center}.metric-strip{scrollbar-width:thin;grid-template-columns:repeat(5,minmax(96px,1fr));overflow-x:auto}.speed-lab{grid-template-columns:repeat(2,minmax(0,1fr))}.speed-lab-title,.speed-preview,.speed-lab-buttons{grid-column:1/-1}.speed-lab-buttons{justify-content:flex-end}.control-tip{display:none}}@media (width<=640px){.question-card{padding:13px 15px}.question-text{font-size:14px}.scene-toolbar{top:9px;right:9px}.checkpoint-track{gap:20px;padding:5px 13px;top:53px}.checkpoint-track span{width:27px;height:27px;font-size:16px}.checkpoint-track b{top:31px}.chase-commentary{width:max-content;padding:7px 11px;top:105px}.round-tool{min-height:38px;padding:0 10px;font-size:11px}.icon-tool{width:38px;height:38px}.learning-panel{width:calc(100% - 18px);top:58px;left:9px}.compact-gap-pill{top:9px;left:9px}.metric-grid .metric{padding:6px 8px}.scene-stage{height:430px}.teacher{width:clamp(64px,17vw,90px)}.xiaoman{width:clamp(60px,15.5vw,84px)}.home-marker{display:none}.control-deck{grid-template-columns:1fr;padding:11px 12px 14px}.learning-dock{grid-template-columns:1fr;gap:7px}.learning-dock.is-collapsed{grid-template-columns:auto 1fr}.learning-dock.is-collapsed.has-speed-lab{grid-template-columns:1fr}.dock-actions{flex-direction:row}.data-toggle,.speed-lab-toggle{flex:1;min-height:38px}.speed-lab{grid-template-columns:1fr;padding:11px}.speed-lab-title,.speed-lab label,.speed-preview,.speed-lab-buttons{grid-column:1}.speed-lab-buttons{grid-template-columns:1fr 1fr;display:grid}.metric-strip{grid-template-columns:repeat(2,minmax(0,1fr));overflow:visible}.metric-strip .metric:first-child{grid-column:1/-1}.control-buttons{flex-wrap:wrap;justify-content:center}.time-scrubber{order:-1}.formula-row{gap:5px}.formula-input{width:54px;height:48px;font-size:19px}.formula-unit{width:100%}.quiz-actions{flex-direction:column-reverse}.quiz-actions button{width:min(260px,100%)}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}
