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@media(min-width:370px) and (max-width:760px) and (min-height:741px){.practice-visual{transform:scale(.94);right:-2%;bottom:8%;width:91%}.reading-mode .practice-visual{transform:scale(.94)!important}}
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/* Each chapter carries a different scroll-driven spatial movement. */
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.enhanced .knowledge-visual{scale:calc(1 + var(--phase,0) * .15)}
.enhanced .finale-art{scale:calc(1 - var(--phase,0) * .35)}
.reading-mode .scene{--phase:0!important}
:root:not(.enhanced) .site-header{background:var(--blue)}
@media(max-height:580px){.reading-mode .scene{min-height:800px}.reading-mode .scene-finale{min-height:760px}}

[data-chapter="5"] .chapter-counter{opacity:0}

/* Edition II — light, depth, and a continuous mathematical world. */
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.sculpture-canvas{position:absolute;inset:0;z-index:2;width:100%;height:100%;pointer-events:none;opacity:.7;mix-blend-mode:normal}
.scene-hero .sculpture-canvas{opacity:.55}.scene-capture .sculpture-canvas{opacity:.65}.scene-guide .sculpture-canvas{opacity:1}.scene-finale .sculpture-canvas{opacity:.55}
.chapter-transition{position:absolute;z-index:18;left:7%;top:48%;display:flex;flex-direction:column;gap:12px;opacity:0;color:var(--rail-color);pointer-events:none;transition:color .5s}
.transition-number{font:italic 104px/.9 Georgia,serif;letter-spacing:-7px;font-weight:400;opacity:.5}
.transition-label{font-family:"Songti SC","STSong",serif;font-size:19px;letter-spacing:8px;opacity:.85;padding-left:4px}
.headline-glyph{--letter-in:clamp(0,calc(var(--text-in,1)*1.55 - var(--glyph-index,0)*.03),1);display:inline-block;opacity:var(--letter-in);transform:translate3d(0,calc((1 - var(--letter-in))*85%),0) rotateX(calc((1 - var(--letter-in))*45deg));filter:blur(calc((1 - var(--letter-in))*3px));transform-origin:center bottom;backface-visibility:hidden}
.hero-copy h1 .headline-glyph{animation:opening-letter 1.2s cubic-bezier(.16,1,.3,1) both;animation-delay:calc(.1s + var(--glyph-index)*.027s)}
.hero-copy .eyebrow{animation:opening-soft 1.3s ease both}
.hero-copy .intro{animation:opening-soft 1.4s .3s ease both}
.hero-copy .round-link{animation:opening-soft 1.4s .5s ease both}
.site-header{animation:opening-soft 1.1s ease both}
.hero-copy h1{font-weight:400;letter-spacing:-3.5px;line-height:1.32}
.copy h2{font-weight:400;letter-spacing:-2px;line-height:1.35}
.copy h2 .accent,.copy h2 .mint{font-family:"Songti SC","STSong",serif;font-weight:500}
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.hero-copy .eyebrow{font-size:11px;letter-spacing:3px}
.hero-shade{background:linear-gradient(90deg,#1234df40,transparent 60%),linear-gradient(0deg,#0923c33d,transparent 25%)}
.hero-art{filter:saturate(.93) contrast(1.02)}
.hero-horizon{position:absolute;left:45%;right:-25%;top:6%;height:110%;border:1px solid #ffffff2b;border-radius:50%;transform:rotate(-30deg) rotateX(55deg);z-index:2;pointer-events:none;box-shadow:0 0 0 44px #ffffff03,0 0 0 90px #ffffff02;opacity:.65}
.hero-orbit{display:grid;place-items:center;border:1px solid #ffffff68;border-radius:50%;background:radial-gradient(circle at 27% 20%,#ffffffc7 0%,#ffffff29 15%,#8ca7ff0d 42%,#030d7140 73%,#e4edff80 98%);box-shadow:inset 2px 3px 5px #fff9,inset -6px -7px 18px #0c167f4d,8px 15px 38px #0c188b22;backdrop-filter:blur(3px);opacity:.9;isolation:isolate;animation:orbit-float 8s ease-in-out infinite}
.hero-orbit:before{content:"";position:absolute;inset:10% 19% 68% 17%;border-radius:50%;background:linear-gradient(180deg,#ffffff9c,transparent);transform:rotate(-29deg);filter:blur(2px)}
.hero-orbit>span{font-weight:400;text-shadow:0 1px 14px #fff9;opacity:.85;line-height:1;transform:rotate(-7deg)}
.orbit-one{width:73px;height:73px;right:7%;top:22%;font-size:35px;transform:rotate(15deg);animation-delay:-1s}
.orbit-two{width:109px;height:109px;left:52%;bottom:15%;font-size:52px;transform:rotate(-19deg);animation-delay:-4s;animation-duration:10s}
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.art-caption{bottom:138px;font-size:8px;letter-spacing:2px;text-shadow:0 1px 7px #0a24b2b3}
.crosshair{animation:slow-turn 24s linear infinite;transform-origin:50% 50%;font-size:20px}
.tiny-star{animation:slow-turn 30s linear infinite}
.header-cta,.round-link,.finale-button{translate:var(--magnet-x,0px) var(--magnet-y,0px);transition:translate .3s cubic-bezier(.2,.8,.2,1),box-shadow .3s,background .3s}
.header-cta{border-color:color-mix(in srgb,currentColor 25%,transparent);backdrop-filter:blur(12px);background:#ffffff04}
.round-arrow{position:relative;isolation:isolate}
.round-arrow:after{content:"";position:absolute;inset:-7px;border:1px solid currentColor;border-radius:50%;opacity:0;transform:scale(.8);transition:opacity .4s,transform .5s;z-index:-1}
.round-link:hover .round-arrow:after{opacity:.2;transform:scale(1.1)}
.scene-capture{background:radial-gradient(ellipse at 74% 50%,#fffdf8 0%,#f3f1ea 55%)}
.capture-aura{position:absolute;width:72%;aspect-ratio:1;top:11%;left:16%;background:radial-gradient(ellipse,#b3c9f039 0%,transparent 66%);border-radius:50%;animation:aura-breathe 7s ease-in-out infinite}
.camera-frame{scale:1.15;border-radius:25px;rotate:calc(var(--mouse-x)*6deg);transition:rotate .5s}
.camera-frame:after{content:"";position:absolute;inset:18px;border:1px solid #173ce91c;border-radius:50%;transform:rotateX(58deg);box-shadow:0 0 0 23px #173ce905}
.phone{box-shadow:inset 0 0 0 1px #9a9b9e,4px 4px 0 #8d8e91,15px 22px 40px #3c48601a,35px 50px 90px #3c486023;animation:object-float 8s ease-in-out infinite}
.capture-tag{animation:label-float 7s ease-in-out infinite;animation-delay:-2s}
.section-watermark{font-weight:400;opacity:.028;letter-spacing:-.065em;translate:calc(var(--phase,0)*-75px) 0}
.scene-guide{background:radial-gradient(ellipse at 25% 60%,#1a363d 0%,#0b1e28 67%)}
.guide-glow{background:radial-gradient(ellipse,#b1edcf26,transparent 65%);width:95vw;height:95vw;left:-43vw;bottom:-68vw;animation:aura-breathe 9s ease-in-out infinite}
.guide-sheet{border-color:#c1e4d627;background:linear-gradient(135deg,#34505a9c,#122731d9);box-shadow:0 30px 100px #0003,inset 0 1px 0 #ffffff0f;backdrop-filter:blur(24px);transform:rotate(-3deg) rotateY(calc(var(--mouse-x)*7deg)) rotateX(calc(var(--mouse-y)*-6deg));transition:transform .5s ease}
.guide-sheet:after{content:"";position:absolute;left:15%;right:15%;bottom:-1px;height:1px;background:linear-gradient(90deg,transparent,#d6f8df78,transparent)}
.step-orb{background:radial-gradient(circle at 30% 25%,#608b8555,#17313b80 65%);box-shadow:inset 0 1px 0 #ffffff25,0 0 35px #c4f6d515;backdrop-filter:blur(9px)}
.orb-a{animation:orbit-float 7s ease-in-out infinite}.orb-b{animation:orbit-float 9s ease-in-out infinite;animation-delay:-4s}.orb-c{animation:orbit-float 11s ease-in-out infinite;animation-delay:-2s}
.editorial-note p{font-size:27px;letter-spacing:3px;line-height:1.8}
.scene-practice{background:radial-gradient(ellipse at 70% 48%,#faf8ff,#eeedf4 65%)}
.practice-orbit{width:115%;transform:rotateX(58deg) rotate(-25deg);border-color:#7670b52b;box-shadow:0 0 0 35px #7670b505,0 0 0 70px #7670b503}
.practice-ribbon{position:absolute;inset:10% -10%;border:1px solid #827cb51c;border-radius:50%;transform:rotate(-33deg) rotateX(50deg);pointer-events:none}
.front-sheet{background:linear-gradient(125deg,#fffefa 15%,#f6f3ea);border:1px solid #fff;box-shadow:0 10px 15px #4e426708,10px 32px 60px #4e42671a,inset 0 1px 0 #fff;transform:rotate(4deg) rotateY(calc(var(--mouse-x)*9deg)) rotateX(calc(var(--mouse-y)*-5deg));transition:transform .5s,opacity .25s}
.back-one{background:linear-gradient(120deg,#dedff0,#eeedf6);box-shadow:0 22px 70px #4e42671a}.back-two{background:linear-gradient(120deg,#efedf5,#fdfbff)}
.practice-annotation{opacity:.7}
.scene-knowledge{background:radial-gradient(ellipse at 75% 55%,#f8fbff,#e8eff7 68%)}
.knowledge-lines{stroke:#7997c8;stroke-width:.7;opacity:.5}
.knowledge-lines>circle:nth-child(2){stroke-dasharray:1 9;animation:orbit-dash 16s linear infinite}
.knowledge-core{background:radial-gradient(circle at 30% 20%,#fff,#e0eaf7 65%,#c9d9ee);box-shadow:inset 0 2px 5px #fff,20px 25px 60px #6b8bbc2a,-10px -10px 35px #ffffffa6;border:1px solid #fff;isolation:isolate}
.core-ripple{position:absolute;inset:-17px;border:1px solid #7f9dce1c;border-radius:50%;z-index:-1;animation:core-wave 6s ease-in-out infinite}
.core-ripple:after{content:"";position:absolute;inset:-18px;border:1px solid #7f9dce16;border-radius:50%}
.core-symbol{background:linear-gradient(120deg,#6f94da,#173ce9 45%,#92c5e8);background-clip:text;-webkit-background-clip:text;color:transparent;animation:slow-turn 40s linear infinite}
.knowledge-node i{box-shadow:0 0 0 1px #9db1d338,0 4px 13px #7491c229;transition:transform .5s,box-shadow .5s,background .5s}
.knowledge-node:hover i,.knowledge-node.active i{box-shadow:0 0 0 1px #173ce94d,0 0 0 9px #173ce908,0 0 25px #173ce936}
.knowledge-node.mastered i{box-shadow:0 0 0 1px #44816866,0 0 0 9px #44816809,0 0 25px #44816826}
.scene-finale{background:radial-gradient(ellipse at 50% 25%,#3154ef,#102fcb 70%)}
.finale-art{opacity:.18;filter:saturate(.7);background:linear-gradient(90deg,#173ce9c9,#173ce966),url('assets/math-journey.webp') 85% 50%/cover no-repeat}
.finale-light{position:absolute;z-index:1;left:10%;right:10%;top:-60%;height:150%;border-radius:50%;background:radial-gradient(ellipse,#c3d5ff1f 0%,transparent 60%);filter:blur(30px);animation:aura-breathe 9s ease-in-out infinite}
.finale-halo{width:70vw;height:70vw;right:15vw;top:15%;border-color:#ffffff1c;transform:rotateX(63deg);box-shadow:0 0 0 85px #ffffff03,0 0 0 170px #ffffff02}
.finale-content h2{font-weight:400;letter-spacing:-2px;font-size:clamp(64px,7vw,112px);text-shadow:0 2px 25px #294dd51a}
.finale-button{box-shadow:0 5px 30px #051d9b30,inset 0 1px 0 #fff;border:1px solid #fff;background:linear-gradient(135deg,#fffef6,#e5eafb)}
.mastery-track>div>span{background:#ffffff08;box-shadow:inset 0 1px 0 #ffffff24;backdrop-filter:blur(5px)}
.mastery-track>i{background:linear-gradient(90deg,transparent,#ffffff80,transparent)}
.reading-mode .scene .copy,.reading-mode .scene .visual,.reading-mode .finale-content{filter:none!important;opacity:1!important}
.reading-mode .chapter-transition,.reading-mode .sculpture-canvas,.reading-mode .film-grain{display:none}
.reading-mode .headline-glyph{transform:none!important;filter:none!important;opacity:1!important}
.reading-mode .scene *{animation:none!important}
.scene:not(.is-active) .hero-orbit,.scene:not(.is-active) .phone,.scene:not(.is-active) .step-orb,.scene:not(.is-active) .core-ripple,.scene:not(.is-active) .core-symbol{animation-play-state:paused}
@keyframes opening-letter{from{opacity:0;transform:translate3d(0,75%,0) rotateX(40deg);filter:blur(8px)}to{opacity:1;transform:translateZ(0);filter:blur(0)}}
@keyframes opening-soft{from{opacity:0;translate:0 16px}to{opacity:1;translate:0 0}}
@keyframes orbit-float{0%,100%{translate:0 0}50%{translate:7px -15px}}
@keyframes object-float{0%,100%{translate:0 0}50%{translate:0 -9px}}
@keyframes label-float{0%,100%{translate:0 0}50%{translate:-6px -9px}}
@keyframes slow-turn{to{rotate:360deg}}
@keyframes core-wave{0%,100%{scale:1;opacity:.5}50%{scale:1.05;opacity:1}}
@keyframes aura-breathe{0%,100%{scale:.94;opacity:.65}50%{scale:1.08;opacity:1}}
@keyframes orbit-dash{to{stroke-dashoffset:200}}
@media(max-width:760px){
 .hero-copy h1{font-size:clamp(34px,8vw,57px);letter-spacing:-1.5px;line-height:1.4}
 .hero-copy .eyebrow{font-size:9px;letter-spacing:2px}.copy h2{letter-spacing:-1px;line-height:1.35}
 .hero-shade{background:linear-gradient(90deg,#1536de99 0%,#1536de30 70%,transparent),linear-gradient(0deg,#102cc64d,transparent 35%)}
 .orbit-one{width:47px;height:47px;top:15%;right:9%;font-size:25px}
 .orbit-two{width:69px;height:69px;left:17%;bottom:20%;font-size:33px}
 .orbit-three{width:28px;height:28px;top:64%;right:15%;font-size:14px}
 .hero-horizon{left:25%;right:-80%;top:24%;height:78%;opacity:.4}
 .art-caption{font-size:6px;bottom:13%;letter-spacing:1px}.crosshair{font-size:16px}
 .chapter-transition{left:8%;top:33%;gap:13px}.transition-number{font-size:79px;letter-spacing:-5px}.transition-label{font-size:15px;letter-spacing:5px}
 .guide-sheet{transform:rotate(-2deg)}.front-sheet{transform:rotate(4deg)}
 .capture-aura{width:130%;left:-30%;top:0}.camera-frame{scale:1.05}
 .sculpture-canvas{opacity:.4}.scene-guide .sculpture-canvas{opacity:.55}.scene-finale .sculpture-canvas{opacity:.4}
 .film-grain{opacity:.025}.finale-halo{width:130vw;height:130vw;right:-15vw;top:33%;transform:rotateX(65deg)}
 .finale-content h2{font-size:clamp(55px,14vw,80px);letter-spacing:-2px}
 .finale-art{opacity:.14}.core-ripple{inset:-10px}.core-ripple:after{inset:-12px}
}
@media(max-width:760px) and (max-height:740px){.copy h2{font-size:30px}.finale-content h2{font-size:51px}.orbit-one{top:14%}.orbit-two{bottom:18%}}
@media(prefers-reduced-motion:reduce){.sculpture-canvas,.chapter-transition{display:none}.headline-glyph{transform:none!important;filter:none!important;opacity:1!important}.phone,.hero-orbit,.step-orb,.core-ripple,.core-symbol,.tiny-star,.crosshair{animation:none!important}.round-link,.header-cta,.finale-button{translate:none!important}}

/* Mobile is a continuous story: content determines height, never a clipped slide. */
.mobile-flow{overflow-x:clip;-webkit-text-size-adjust:100%;text-size-adjust:100%}
.enhanced.mobile-flow .experience{height:auto}
.enhanced.mobile-flow .stage{position:relative;height:auto;overflow:clip;perspective:none}
.enhanced.mobile-flow .scene{position:relative;inset:auto;height:auto;min-height:100svh;opacity:1;visibility:visible;transform:none;pointer-events:auto;will-change:auto;isolation:isolate}
.mobile-flow .scene .copy,.mobile-flow .scene .visual{pointer-events:auto!important}
.mobile-flow .scene-inner{width:calc(100% - 48px);max-width:560px;height:auto}
.mobile-flow .split-layout{display:flex;flex-direction:column;align-items:stretch;gap:32px;padding:96px 0 72px}
.mobile-flow .reverse-layout .copy{order:-1}
.mobile-flow .copy,.mobile-flow .visual{opacity:calc(.4 + var(--flow-reveal,1)*.6);translate:0 calc((1 - var(--flow-reveal,1))*24px);transition:opacity .15s linear,translate .15s linear}
.mobile-flow .headline-glyph{filter:none;transform:none;opacity:1}
.mobile-flow .copy h2{font-size:clamp(32px,8.8vw,46px);letter-spacing:-1.4px;line-height:1.35}
.mobile-flow .eyebrow{font-size:11px;letter-spacing:1.8px;margin-bottom:20px;gap:12px}
.mobile-flow .chapter-no{font-size:11px}
.mobile-flow .intro{font-size:14px;line-height:1.95;letter-spacing:0;margin-top:20px;opacity:.8}
.mobile-flow .demo-note{font-size:11px;line-height:1.75;max-width:none!important;margin-top:12px;opacity:.6}
.mobile-flow .round-link{font-size:13px;gap:14px;min-height:48px;margin-top:24px}
.mobile-flow .round-link small{font-size:8px;letter-spacing:.8px}
.mobile-flow .round-arrow{width:46px;height:46px;flex-shrink:0}
.mobile-flow .site-header{padding:calc(10px + env(safe-area-inset-top)) 20px 10px;background:color-mix(in srgb,var(--header-bg,#173ce9) 88%,transparent);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px)}
.mobile-flow .site-header .brand{font-size:20px;gap:10px;min-height:44px;letter-spacing:1px}
.mobile-flow .site-header nav{display:none}
.mobile-flow .header-cta{min-height:44px;font-size:12px;padding:9px 14px;gap:12px}
.mobile-flow .chapter-rail,.mobile-flow .chapter-counter,.mobile-flow .chapter-transition,.mobile-flow #math-dust,.mobile-flow .film-grain{display:none}
.mobile-flow .motion-toggle{bottom:calc(12px + env(safe-area-inset-bottom));right:max(16px,env(safe-area-inset-right));min-height:44px;padding:9px 14px;gap:6px;font-size:11px;border:1px solid color-mix(in srgb,currentColor 16%,transparent);border-radius:24px;opacity:.9;background:color-mix(in srgb,var(--header-bg,#173ce9) 92%,transparent);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}
.mobile-flow .motion-toggle>span:first-child{font-size:18px}
.mobile-flow .reading-progress{height:3px;bottom:0;padding-bottom:env(safe-area-inset-bottom)}
.mobile-flow .scene-hero{min-height:max(740px,100svh)}
.mobile-flow .hero-inner{padding-top:calc(134px + env(safe-area-inset-top));padding-bottom:330px}
.mobile-flow .hero-copy{width:100%;padding:0}
.mobile-flow .hero-copy h1{font-size:clamp(32px,8.9vw,49px);line-height:1.4;letter-spacing:-1.7px}
.mobile-flow .hero-copy .eyebrow{font-size:10px;letter-spacing:1.6px;margin-bottom:24px}
.mobile-flow .hero-copy .intro{font-size:14px;margin-top:22px;line-height:1.9}
.mobile-flow .hero-copy .round-link{margin-top:26px}
.mobile-flow .hero-art{inset:0;background-position:64% 70%;transform:none!important}
.mobile-flow .hero-shade{background:linear-gradient(180deg,#173ce9c9 0%,#1436e3c2 32%,#1335d96e 58%,#102cc608 80%),linear-gradient(90deg,#1538e54d,transparent)}
.mobile-flow .hero-bottom{left:24px;right:24px;bottom:calc(80px + env(safe-area-inset-bottom));font-size:10px;gap:18px;align-items:flex-end;opacity:.85}
.mobile-flow .hero-bottom>a{max-width:155px;min-height:44px;gap:10px;line-height:1.7}
.mobile-flow .hero-bottom>span:last-child{display:none}
.mobile-flow .art-caption{display:none}
.mobile-flow .orbit-one{top:61%;right:9%;width:51px;height:51px}
.mobile-flow .orbit-two{bottom:16%;left:12%;width:67px;height:67px}
.mobile-flow .orbit-three{top:80%;right:32%}
.mobile-flow .visual{position:relative;inset:auto;width:100%;height:auto;min-height:0;max-height:none;transform:none!important;scale:1!important;margin:0;flex-shrink:0;perspective:900px}
.mobile-flow .detail-line{font-size:11px;margin-top:20px;gap:10px;flex-wrap:wrap}
.mobile-flow .detail-line i{width:14px}
.mobile-flow .capture-visual{height:460px;display:flex;justify-content:center;align-items:center}
.mobile-flow .phone{width:230px;height:456px;padding:8px;border-radius:37px;transform:rotate(-7deg) rotateY(-8deg);transform-origin:center;rotate:0;animation-duration:10s}
.mobile-flow .phone-top{height:24px;font-size:9px}
.mobile-flow .phone-title{height:40px;font-size:12px}
.mobile-flow .camera-content{height:280px;padding:26px 16px}
.mobile-flow .paper-label{font-size:9px;letter-spacing:1px}
.mobile-flow .paper-question{font-size:13px;margin-top:25px}
.mobile-flow .formula-main{font-size:28px}
.mobile-flow .handwriting{font-size:15px;margin-top:34px}
.mobile-flow .capture-toolbar{height:62px;font-size:19px}
.mobile-flow .shutter{width:46px;height:46px}
.mobile-flow .phone-home{margin:8px auto}
.mobile-flow .camera-frame{width:265px;height:305px;right:auto;scale:1}
.mobile-flow .capture-tag{right:0;bottom:25px;font-size:11px;padding:12px 16px;transform:rotate(-3deg)}
.mobile-flow .scan-result{padding:16px 12px}
.mobile-flow .scan-result span{font-size:11px}
.mobile-flow .scan-result strong{font-size:12px;line-height:1.6}
.mobile-flow .guide-visual{padding:22px 0;min-height:0}
.mobile-flow .guide-sheet{position:relative;inset:auto;width:100%;padding:22px 20px;transform:rotate(-1.5deg);backdrop-filter:none}
.mobile-flow .sheet-heading{font-size:11px;gap:8px}
.mobile-flow .demo-badge{font-size:9px}
.mobile-flow .guide-progress{font-size:11px;margin-top:23px;letter-spacing:.4px}
.mobile-flow .guide-sheet h3{font-size:17px;line-height:1.7;margin-top:19px}
.mobile-flow .guide-equation{font-size:27px;margin:20px 0}
.mobile-flow .guide-options{gap:9px}
.mobile-flow .guide-options button{min-height:48px;padding:12px 10px;font-size:15px;gap:3px}
.mobile-flow .guide-feedback{font-size:13px;line-height:1.8;min-height:46px;margin-top:17px}
.mobile-flow .text-button{font-size:13px;min-height:44px;padding:11px 0}
.mobile-flow .orb-a{left:-8px;top:0;width:34px;height:34px}
.mobile-flow .orb-c{right:4px;bottom:-4px;width:38px;height:38px}
.mobile-flow .editorial-note,.mobile-flow .fine-line{display:none}
.mobile-flow .practice-selector{gap:20px;margin-top:25px}
.mobile-flow .practice-selector button{width:72px;min-height:64px;font-size:23px;padding:12px 0}
.mobile-flow .practice-selector button span{font-size:11px;margin-top:7px;letter-spacing:1px}
.mobile-flow .practice-visual{display:grid;place-items:center;padding:30px 0 34px;min-height:0}
.mobile-flow .exercise-sheet{width:calc(100% - 24px);max-width:360px;height:auto;padding:25px 22px}
.mobile-flow .front-sheet{position:relative;min-height:426px;transform:rotate(2deg);overflow-wrap:anywhere}
.mobile-flow .back-sheet{height:85%;max-height:430px;top:7%;padding:20px}
.mobile-flow .back-one{transform:translate(-10px,4px) rotate(-6deg)}
.mobile-flow .back-two{transform:translate(10px,0) rotate(7deg)}
.mobile-flow .exercise-top{font-size:12px;padding-bottom:15px}
.mobile-flow .exercise-topic{font-size:11px;margin-top:21px}
.mobile-flow .front-sheet h3{font-size:16px;line-height:1.6;margin-top:12px}
.mobile-flow .exercise-math{font-size:33px;margin-top:23px;min-height:66px}
.mobile-flow .front-sheet>p:not(.exercise-answer){font-size:13px;line-height:1.8}
.mobile-flow .answer-button{font-size:13px;min-height:48px;padding:12px 0;margin-top:8px}
.mobile-flow .exercise-answer{font-size:13px;line-height:1.85}
.mobile-flow .exercise-footer{font-size:9px;padding-top:20px}
.mobile-flow .knowledge-selection{margin-top:25px;padding-left:16px}
.mobile-flow .small-label{font-size:11px}
.mobile-flow .knowledge-selection h3{font-size:16px;margin-top:10px}
.mobile-flow .mastered-toggle{font-size:13px;min-height:44px;margin-top:9px;padding:8px 0}
.mobile-flow .check-square{width:20px;height:20px;font-size:12px}
.mobile-flow .knowledge-visual{width:100%;height:auto;aspect-ratio:1;margin:10px 0 35px}
.mobile-flow .knowledge-lines{display:block;width:100%;height:100%}
.mobile-flow .knowledge-core{width:112px;height:112px}
.mobile-flow .knowledge-core strong{font-size:12px;letter-spacing:0}
.mobile-flow .knowledge-core small{font-size:8px;letter-spacing:0}
.mobile-flow .knowledge-node{min-width:88px;min-height:60px;padding:8px 4px}
.mobile-flow .knowledge-node>span{font-size:12px;margin-top:10px;letter-spacing:0;white-space:nowrap}
.mobile-flow .knowledge-node small{font-size:10px;margin-top:5px;white-space:nowrap}
.mobile-flow .knowledge-satellite{font-size:10px;gap:8px}
.mobile-flow .map-caption{left:0;right:0;bottom:-30px;justify-content:center;font-size:11px;letter-spacing:0}
.mobile-flow .scene-finale{display:flex;flex-direction:column;min-height:100svh;padding:0 24px}
.mobile-flow .finale-content{width:100%;max-width:560px;padding:110px 0 52px}
.mobile-flow .finale-content .eyebrow{font-size:11px;margin-bottom:28px;letter-spacing:1px}
.mobile-flow .finale-content h2{font-size:clamp(52px,15vw,76px);line-height:1.25}
.mobile-flow .finale-content .intro{font-size:14px;margin-top:25px}
.mobile-flow .mastery-track{gap:8px;margin-top:32px}
.mobile-flow .mastery-track>div{min-width:0;flex:1}
.mobile-flow .mastery-track>div>span{width:34px;height:34px;font-size:12px}
.mobile-flow .mastery-track>div>p{font-size:11px;line-height:1.6;margin-top:11px;text-wrap:balance}
.mobile-flow .mastery-track>i{width:14px;flex-shrink:0;margin-top:17px}
.mobile-flow .mastery-detail{font-size:11px;line-height:1.9;max-width:310px;margin:24px auto 0;opacity:.7}
.mobile-flow .finale-button{font-size:14px;min-height:52px;padding:14px 22px;margin-top:29px;gap:25px}
.mobile-flow .restart-link{font-size:12px;min-height:44px;margin-top:12px;padding:14px}
.mobile-flow .scene-finale footer{position:relative;inset:auto;width:100%;max-width:560px;margin-top:auto;padding:24px 0 calc(88px + env(safe-area-inset-bottom));display:flex;flex-wrap:wrap;gap:18px;align-items:center}
.mobile-flow .scene-finale footer .brand{font-size:17px}
.mobile-flow .scene-finale footer>span{font-size:11px;letter-spacing:0;margin-left:auto}
.mobile-flow .scene-finale footer>small{width:100%;font-size:10px;line-height:1.7}
.mobile-flow dialog{width:calc(100% - 24px);max-width:560px;max-height:calc(100svh - 48px - env(safe-area-inset-top) - env(safe-area-inset-bottom));padding:40px 24px 28px;overscroll-behavior:contain;-webkit-overflow-scrolling:touch}
.mobile-flow .dialog-close{position:sticky;float:right;top:-28px;margin:-24px -12px 0 0;width:44px;height:44px;background:#f8f7f3;border-radius:50%;z-index:2}
.mobile-flow dialog h2{font-size:27px;line-height:1.5;clear:both}
.mobile-flow dialog .dialog-intro,.mobile-flow .overview-list p,.mobile-flow .dialog-footnote{font-size:13px;line-height:1.85}
.mobile-flow .overview-list h3{font-size:15px}
.mobile-flow .overview-list article{padding:17px 0}
.mobile-flow .dialog-done{font-size:13px;min-height:48px}
@media(max-width:360px){.mobile-flow .scene-inner{width:calc(100% - 36px)}.mobile-flow .hero-copy h1{font-size:30px;letter-spacing:-1px}.mobile-flow .guide-sheet{padding:21px 16px}.mobile-flow .guide-options button{font-size:13px}.mobile-flow .knowledge-core{width:94px;height:94px}.mobile-flow .knowledge-core small{font-size:7px}.mobile-flow .knowledge-node>span{font-size:11px}.mobile-flow .knowledge-node small{font-size:9px}.mobile-flow .hero-bottom{left:18px;right:18px;font-size:9px}.mobile-flow .scene-finale{padding:0 18px}}
@media(min-width:761px) and (max-width:1000px) and (max-height:500px){.mobile-flow .scene-inner{max-width:660px}.mobile-flow .split-layout{gap:35px}.mobile-flow .visual{max-width:400px;align-self:center}.mobile-flow .scene-hero{min-height:650px}.mobile-flow .hero-inner{padding-top:120px;padding-bottom:170px}.mobile-flow .hero-copy h1{font-size:48px}.mobile-flow .hero-copy{max-width:530px}.mobile-flow .hero-art{background-position:70% 50%}.mobile-flow .hero-shade{background:linear-gradient(90deg,#173ce9df,transparent)}.mobile-flow .scene-finale footer{display:flex}}