.experience-header{height:auto;min-height:85px;flex-wrap:wrap;padding-top:18px;padding-bottom:18px}.experience-header .brand{text-decoration:none}.experience-header .brand img{width:38px;height:38px}.experience-header .nav{flex-wrap:wrap}.experience-header .nav a{font-size:13px;font-weight:700;text-decoration:none;padding:11px 14px;border-radius:8px}.experience-header .nav a[aria-current=page]{background:var(--navy);color:white}.family-return{font-size:12px;text-underline-offset:4px}.experience-home{min-height:540px}.experience-home .intro{max-width:460px;font-size:17px}.experience-home .home-note{font-size:12px;line-height:1.6}.intro-preview{background:white;padding:30px;border-radius:24px;box-shadow:0 12px 0 #c2d9e780;margin:16px auto;max-width:490px;transform:rotate(-2deg)}.intro-preview svg{width:100%;height:auto}.intro-preview p{text-align:center;font-size:14px;line-height:1.6;margin-top:18px}.intro-preview strong{font-size:25px}.experience-home .visual-world{padding-bottom:36px}.experience-home .primary{text-decoration:none}.experience-home h1 em{color:#377ea7}.experience-how{margin-bottom:30px}.experience-how .how-item{line-height:1.6}.experience-how .how-item b{flex-shrink:0}
.fluency-main{width:min(1080px,100%);padding:40px 28px 55px;margin:auto}.fluency-title{display:grid;grid-template-columns:1.1fr 1fr;gap:35px;align-items:center}.fluency-title h1{font-size:clamp(39px,5vw,62px);letter-spacing:-2px;margin:15px 0}.fluency-title .lead{font-size:18px;line-height:1.65;color:var(--muted);max-width:600px}.fluency-values{display:grid;gap:12px}.fluency-values p{background:#eaf2f4;padding:15px 18px;border-radius:12px;font-size:14px;line-height:1.5}.fluency-values strong{color:var(--navy);display:block;font-size:17px;margin-bottom:3px}.fluency-context{font-size:15px;line-height:1.75;color:var(--muted);margin:24px 0;max-width:850px}.fluency-bands{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:30px 0 22px}.fluency-bands button{min-height:65px;padding:12px 15px;border:1px solid #cbdbe3;border-radius:14px;background:#ffffffd9;font-weight:700;font-size:14px;line-height:1.4;box-shadow:0 2px 5px #172f5005;transition:background .18s,border-color .18s,box-shadow .18s}.fluency-bands button[aria-pressed=true]{color:white;background:var(--navy);border-color:var(--navy)}.fluency-band-intro{font-size:15px;color:var(--muted);line-height:1.6;max-width:850px;margin:0 0 22px}.deck-toolbar{display:flex;align-items:center;justify-content:space-between;gap:14px;margin:0 auto 14px;max-width:760px;font-size:12px;color:var(--muted)}.deck-toolbar h2{font-size:17px;color:var(--navy)}.flash-card{display:block;text-align:center;background:white;border:1px solid #cbdbe3;width:100%;max-width:760px;margin:auto;border-radius:26px;padding:25px 30px 16px;box-shadow:0 12px 34px #172f5009,0 2px 5px #172f5005;touch-action:manipulation;transition:border-color .18s,box-shadow .18s}.flash-card:hover{border-color:#96b6c9;box-shadow:0 15px 38px #172f5010,0 3px 8px #172f5008}.flash-card .card-question{font-size:18px;line-height:1.4;font-weight:700;display:block;color:#47667c}.flash-card .model-wrap{display:block;max-width:620px;margin:18px auto 12px;background:#f7fafb;border:1px solid #edf2f5;border-radius:18px;overflow:hidden}.flash-card svg{display:block;width:100%;height:auto;max-height:280px}.flash-card .reveal-cue{display:flex;flex-direction:column;justify-content:center;gap:5px;min-height:45px;font-size:13px;font-weight:700;color:#47667c;padding:7px 0}.flash-card .revealed-total{display:block;font-size:30px;line-height:1.2;font-weight:900;color:var(--deck-color)}.flash-card .reveal-cue small{display:block;font-size:12px;margin-top:7px;font-weight:400}.deck-answer{max-width:760px;margin:20px auto 0;min-height:104px;background:#eaf2ef;border:1px solid #dfeae4;border-radius:16px;padding:18px 23px;font-size:15px;line-height:1.6}.deck-answer.is-hidden{background:transparent;border-color:transparent;color:var(--muted);text-align:center}.fact-row{display:flex;gap:8px 20px;flex-wrap:wrap;margin-bottom:8px;font-weight:700;font-variant-numeric:tabular-nums}.deck-controls{max-width:760px;display:flex;align-items:center;justify-content:space-between;gap:12px;margin:22px auto}.deck-controls button{border:1px solid #cbdbe3;border-radius:12px;background:white;font-size:14px;font-weight:700;padding:12px 18px;min-height:46px}.deck-controls .next{background:var(--navy);color:white;border-color:var(--navy)}.fluency-support{border-top:1px solid var(--line);padding-top:30px;margin-top:40px;display:grid;grid-template-columns:1fr 1fr;gap:20px}.fluency-support article{border-radius:15px;background:#eaf2f6;padding:25px}.fluency-support h2{font-size:23px;margin-bottom:12px}.fluency-support p{font-size:14px;line-height:1.7;margin-bottom:14px;color:var(--muted)}.fluency-support a{font-size:14px;font-weight:700;text-underline-offset:4px}.fluency-source{margin-top:25px;font-size:12px;line-height:1.6;color:var(--muted)}

/* A calm card face: the expression stays visible while only its answer changes. */
.fluency-play-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:24px}
.fluency-play-heading h1{font-size:clamp(34px,4vw,46px);letter-spacing:-1.5px;margin:10px 0}
.fluency-play-heading p:not(.eyebrow){font-size:16px;line-height:1.65;color:var(--muted);max-width:650px}
.fluency-back{font-size:12px;white-space:nowrap;text-underline-offset:4px;padding-bottom:4px}
.fluency-bands button:hover:not([aria-pressed=true]){background:#edf5f8;border-color:#9dbbcf}
#deck-progress{padding:6px 11px;border-radius:30px;background:#eaf1f5;font-variant-numeric:tabular-nums;color:#49657a}
.flash-card .card-equation{display:flex;align-items:center;justify-content:center;gap:15px;margin-top:14px;font-size:clamp(29px,4.5vw,39px);line-height:1.2;font-weight:700;font-variant-numeric:tabular-nums;letter-spacing:-.6px}
.equation-equals{font-weight:400;color:#6a8295}
.equation-result{display:inline-flex;align-items:center;justify-content:center;min-width:76px;height:58px;padding:0 11px;border:1px dashed #b7ccd8;border-radius:13px;background:#f0f6f9;color:#668296}
.is-revealed .equation-result{border-style:solid;border-color:#cfdfd7;background:#eaf2ed;color:#17665a}
.is-revealed .equation-result,.is-revealed .revealed-total{animation:answer-appear .2s ease-out}
.flash-card.quantity-card .reveal-cue{min-height:76px}
.fluency-intro .fluency-intro-detail{font-size:15px;line-height:1.7;margin-top:16px;color:var(--muted)}
.fluency-intro .intro-preview{transform:rotate(-1.5deg);box-shadow:0 14px 30px #172f5010;border:1px solid #d3e1e8;padding:24px}
.fluency-intro-preview .intro-model-question{margin:0;font-size:16px;font-weight:700}
.fluency-intro-preview .intro-model-equation{font-size:32px;font-weight:700;line-height:1.2;margin:0}
.intro-model-equation span{color:#577b93}
.fluency-principles .how-item{flex:1}
.fluency-principles .how-item span{display:inline}
.fluency-intro-resources{max-width:1080px;margin:auto;padding:0 28px 40px}
.fluency-intro-resources .fluency-support{margin-top:10px}
@keyframes answer-appear{from{opacity:.35;transform:translateY(3px)}to{opacity:1;transform:translateY(0)}}
@media(prefers-reduced-motion:reduce){.flash-card,.fluency-bands button{transition:none}.is-revealed .equation-result,.is-revealed .revealed-total{animation:none}}
@media(max-width:900px){.experience-header{gap:16px}.experience-header .nav{order:3;width:100%;justify-content:center}.experience-header .family-return{margin-left:auto}.fluency-title{grid-template-columns:1fr;gap:20px}.fluency-values{grid-template-columns:repeat(3,1fr)}}
@media(max-width:640px){.experience-home{grid-template-columns:1fr;padding:35px 24px}.experience-home h1{font-size:45px}.experience-home .visual-world{margin-top:15px}.experience-how{width:calc(100% - 48px);flex-direction:column;gap:18px;padding:20px 0}.experience-header .nav a{padding:10px 8px;font-size:11px}.experience-header .brand-name{font-size:21px}.fluency-main{padding:28px 18px}.fluency-title h1{font-size:43px}.fluency-title .lead{font-size:16px}.fluency-values{grid-template-columns:1fr;gap:8px}.fluency-values p{padding:11px 15px}.fluency-values strong{display:inline;margin-right:8px}.fluency-bands{grid-template-columns:1fr 1fr;margin-top:22px}.fluency-bands button{font-size:13px;padding:10px;min-height:59px}.flash-card{padding:20px 13px 12px;border-radius:21px}.flash-card .card-question{font-size:18px}.flash-card .model-wrap{margin:16px 0 8px;border-radius:13px}.flash-card .reveal-cue{font-size:13px}.deck-toolbar{font-size:11px}.deck-toolbar h2{font-size:15px}.deck-controls{gap:8px}.deck-controls button{font-size:12px;padding:11px 12px}.deck-answer{padding:16px;font-size:14px}.fluency-support{grid-template-columns:1fr}.fluency-support article{padding:22px}}

@media(max-width:640px){
 .fluency-play-heading{display:block}.fluency-back{display:inline-block;margin-top:14px}
 .flash-card .card-equation{gap:10px;font-size:30px}.equation-result{height:49px;min-width:62px;padding:0 8px}
 .flash-card .card-question{font-size:16px}.flash-card .reveal-cue{font-size:12px}
 .deck-toolbar{gap:8px}#deck-progress{padding:5px 9px}.deck-controls button{padding:11px 9px}
 .fluency-intro-resources{padding:0 18px 30px}.fluency-intro .intro-preview{padding:20px}
 .fluency-intro .intro{font-size:16px;line-height:1.65}.fluency-intro .visual-world{max-width:390px;padding:20px 0}
 .fluency-principles .how-item{font-size:13px}.fluency-principles .how-item span{font-size:12px}
}