*{box-sizing:border-box}body{margin:0;background:#f7f6f2;color:#182e2b;font-family:Arial,sans-serif}button,select{font:inherit}button{cursor:pointer;transition:background .2s,transform .2s}button:focus-visible,a:focus-visible,select:focus-visible{outline:3px solid #df8651;outline-offset:4px}header{max-width:1200px;margin:auto;padding:26px 32px;border-bottom:1px solid #dedfd7;display:flex;justify-content:space-between;align-items:center}.brand{text-decoration:none;color:inherit;font-weight:700;display:flex;align-items:center;gap:12px}.logo{background:#234e43;color:white;border-radius:12px;padding:10px;font-size:24px}.badge,.eyebrow{font-size:11px;font-weight:700;letter-spacing:2px}.badge{color:#78857d}main{max-width:1100px;margin:auto;padding:44px 32px 24px}.intro h1{font-size:42px;line-height:1.14;letter-spacing:-1.5px;margin:16px 0}.intro em{font-family:Georgia,serif;font-weight:400;color:#547b65}.intro p{color:#768078;line-height:1.65;font-size:15px}.workspace{display:grid;grid-template-columns:260px 1fr;gap:55px;margin-top:40px}nav{display:grid;gap:8px;margin-top:18px}nav button{display:flex;gap:12px;align-items:center;text-align:left;background:none;border:0;border-radius:12px;padding:15px;color:#607069;font-size:13px}nav button.active{background:#e5ebe0;color:#214d3f;font-weight:bold}nav button span{opacity:.6;font-size:11px}.progressbox{margin-top:28px;border-top:1px solid #dddfd7;padding-top:24px;font-size:13px}progress{display:block;width:100%;height:6px;margin:14px 0;accent-color:#365d48}.progressbox small{font-size:11px;line-height:1.6;color:#7d857d}.toolbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;color:#6a786e;font-size:12px}.subtle{border:0;background:none;color:#45664e;padding:8px}.scene{perspective:1200px}#card{position:relative;height:340px;transform-style:preserve-3d;transition:transform .55s}#card.flipped{transform:rotateY(180deg)}.face{position:absolute;inset:0;backface-visibility:hidden;border:1px solid #dce2d5;border-radius:22px;background:#fff;box-shadow:0 12px 28px #213e2b08;padding:25px 30px;display:flex;flex-direction:column}.back{transform:rotateY(180deg);background:#e8efdf}.cardtop{display:flex;justify-content:space-between;font-size:10px;letter-spacing:2px;color:#6a826f}.center{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center}h2{font-size:35px;font-weight:600;letter-spacing:-1px;margin:20px 0;line-height:1.2}.audio{background:#285641;color:white;border:0;border-radius:40px;padding:13px 22px;font-size:13px}.settings{display:flex;gap:18px;margin-top:18px;font-size:11px;color:#718174;align-items:center}.settings label{display:flex;gap:5px;align-items:center}select{border:0;background:#f1f4ed;border-radius:4px;color:#3e5c49}.flip{background:none;border:0;color:#67806a;font-size:12px;padding:8px}.controls{display:flex;gap:12px;justify-content:space-between}.controls button{border:1px solid #d5ddcf;background:white;border-radius:12px;padding:14px 21px;color:#335841}.controls .learn{flex:1;background:#e6eddf;border-color:#e6eddf;font-size:13px}.controls button:disabled{opacity:.3;cursor:default}.hint{text-align:center;font-size:10px;color:#8a9288;margin:18px 0}#note{font-size:14px;color:#667760}#audioStatus{font-size:12px;color:#8e4e36;min-height:16px;margin:10px 0}footer{display:flex;justify-content:space-between;border-top:1px solid #dedfd7;margin-top:45px;padding-top:20px;font-size:11px;color:#879082}@media(max-width:700px){header{padding:18px 20px}.badge{display:none}main{padding:28px 20px}.intro h1{font-size:32px}.intro p{font-size:13px}.workspace{grid-template-columns:1fr;gap:20px;margin-top:25px}nav{display:flex;overflow-x:auto;padding-bottom:6px;margin-top:10px}nav button{white-space:nowrap;padding:12px}.progressbox{margin-top:10px;padding-top:12px}.progressbox small{display:none}.face{padding:20px}#card{height:330px}h2{font-size:29px}footer{margin-top:25px;line-height:1.6;gap:15px}footer span{text-align:right}.controls button{padding:14px}.hint{display:none}}@media(prefers-reduced-motion:reduce){#card{transition:none}}

/* Mobile study layout: compact navigation, readable controls, safe-area spacing. */
.mobile-category{display:none}.study,.workspace>aside{min-width:0}button,a,input,select{touch-action:manipulation}button{-webkit-tap-highlight-color:transparent}.face{-webkit-backface-visibility:hidden}h2{overflow-wrap:anywhere}
@media(max-width:700px){
 header{padding:10px max(16px,env(safe-area-inset-right)) 10px max(16px,env(safe-area-inset-left));gap:12px}.brand{font-size:14px;gap:8px}.logo{font-size:20px;padding:8px;border-radius:10px}header .subtle{min-width:48px;min-height:44px;font-size:14px}
 main{padding:18px max(16px,env(safe-area-inset-right)) max(20px,env(safe-area-inset-bottom)) max(16px,env(safe-area-inset-left))}.intro>.eyebrow{font-size:9px;letter-spacing:1.5px}.intro h1{font-size:clamp(23px,6.1vw,30px);line-height:1.12;letter-spacing:-.8px;margin:8px 0}.intro p{font-size:12px;line-height:1.4;margin:8px 0}.intro p br{display:none}
 .workspace{gap:12px;margin-top:16px}.workspace aside>.eyebrow,nav{display:none}.mobile-category{display:flex;align-items:center;gap:12px;font-size:12px;color:#526653}.mobile-category select{flex:1;min-width:0;max-width:100%;min-height:44px;padding:10px 30px 10px 12px;font-size:16px;border:1px solid #d5ddcf;background:#fff;border-radius:10px;color:#244832}
 .progressbox{display:flex;align-items:center;gap:14px;border:0;margin-top:10px;padding:0;font-size:11px}.progressbox strong{white-space:nowrap;font-weight:500}.progressbox progress{margin:0;flex:1;min-width:0}.toolbar{margin-bottom:6px;font-size:11px}.toolbar button{min-height:44px;padding:8px 0 8px 12px;font-size:13px}
 #card{height:clamp(320px,43svh,380px)}.face{padding:18px 20px;border-radius:18px}.cardtop{font-size:9px;letter-spacing:1.5px}.center{min-height:0}h2{font-size:clamp(24px,6.5vw,32px);line-height:1.18;margin:12px 0 16px;letter-spacing:-.6px}.audio{min-height:48px;font-size:14px;padding:13px 24px}.settings{gap:14px;margin-top:10px;font-size:12px;flex-wrap:wrap;justify-content:center}.settings label{min-height:44px;gap:6px}.settings select{font-size:16px;min-height:44px;padding:6px}.settings input{width:20px;height:20px;accent-color:#285641}.flip{min-height:44px;font-size:14px;width:100%;border-top:1px solid #dce2d5;border-radius:0;margin-top:8px;padding:10px}.back .flip{border-color:#cfdbc2}#note{font-size:14px;line-height:1.5;margin:8px 0}
 #audioStatus{min-height:0;margin:0}#audioStatus:not(:empty){margin:10px 0}.controls{gap:8px;margin-top:12px}.controls button{min-height:50px;padding:12px;min-width:48px}.controls .learn{font-size:12px;line-height:1.3;min-width:0}.hint{display:none}footer{margin-top:22px;padding-top:14px;font-size:10px;flex-wrap:wrap;gap:6px}footer span{text-align:left}
}
@media(max-width:360px){main{padding-left:12px;padding-right:12px}.face{padding:16px}.mobile-category{gap:8px;font-size:11px}.mobile-category select{font-size:16px}.settings{gap:8px}.controls .learn{font-size:11px}}
@media(max-width:700px) and (orientation:landscape){.intro{display:none}.workspace{margin-top:0}#card{height:320px}}

/* Keep the phrase at the geometric center, independently of audio controls. */
.face{display:grid;grid-template-rows:44px minmax(0,1fr) 44px}.face .cardtop{align-self:start}.face .center{position:relative;min-width:0;min-height:0}.face h2{margin:0;text-align:center}.face .flip{margin:0;align-self:stretch;min-height:44px}.face #note{position:absolute;top:calc(50% + 30px);left:0;right:0;margin:8px 0 0;font-size:13px;line-height:1.4}
.audio-panel{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:12px 24px;margin-top:16px;padding:14px 16px;border:1px solid #dce2d5;border-radius:16px;background:#eef2e9}.audio-panel .settings{margin:0;gap:16px}.audio-panel .settings label{min-height:44px}.audio-panel .settings select{font-size:16px;min-height:44px;padding:6px}.audio-panel .audio{min-height:48px}.audio-panel input{width:18px;height:18px;accent-color:#285641}
@media(max-width:700px){#card{height:clamp(240px,32svh,300px)}.face{padding:16px 20px}.audio-panel{margin-top:12px;padding:12px;gap:6px}.audio-panel .audio{width:100%;font-size:14px}.audio-panel .settings{width:100%;justify-content:center;gap:20px}.audio-panel .settings label{font-size:12px}.controls{margin-top:12px}}