/* JOM TYPE glass skin: readable surfaces, local pointer light, no layout motion. */
:root{--paper:#f3f7f2;--muted:#657b70;--line:#d5e1d7;--glass-shadow:0 12px 38px #294e3b0a,0 2px 6px #294e3b05}
body{background:radial-gradient(ellipse at 6% 5%,#dfeee4 0,transparent 45%),radial-gradient(ellipse at 95% 38%,#f2ecd8 0,transparent 43%),#f3f7f2;isolation:isolate;overflow-x:clip}
.liquid-backdrop{position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden;contain:strict}
.liquid-orb{position:absolute;border-radius:46% 54% 61% 39%/44% 43% 57% 56%;will-change:transform;filter:blur(46px);opacity:.65}
.liquid-orb--mint{width:500px;height:470px;left:-150px;top:90px;background:radial-gradient(ellipse at 42% 40%,#b6dac6b0,#cce5d540 63%,transparent 75%)}
.liquid-orb--gold{width:440px;height:480px;right:-150px;top:200px;background:radial-gradient(ellipse at 48% 48%,#e8d7aba0,#eee3c640 65%,transparent 77%)}
.liquid-orb--pearl{width:560px;height:400px;left:30%;top:58%;background:radial-gradient(ellipse,#cbded98c,#e5eeea40 61%,transparent 76%)}
.glass-surface{--glass-x:50%;--glass-y:20%;--glass-active:0;position:relative;isolation:isolate;background:#ffffffb8;border:1px solid #ffffffd1;box-shadow:var(--glass-shadow),inset 0 1px 0 #fff,inset 0 -1px 0 #507d6020}
.glass-surface::before{content:"";position:absolute;inset:0;z-index:-1;border-radius:inherit;pointer-events:none;background:radial-gradient(ellipse 230px 150px at var(--glass-x) var(--glass-y),#fff9,transparent 80%),radial-gradient(ellipse 320px 210px at calc(100% - var(--glass-x)) calc(100% - var(--glass-y)),#bbdbc52b,transparent 80%);opacity:calc(.18 + var(--glass-active)*.72);transition:opacity .35s}
.glass-surface::after{content:"";position:absolute;inset:0;z-index:1;border-radius:inherit;pointer-events:none;padding:1px;background:radial-gradient(ellipse 240px 180px at var(--glass-x) var(--glass-y),#fff,transparent 80%),linear-gradient(145deg,#ffffffc9,#b4cbb72b 48%,#ffffffad);-webkit-mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);-webkit-mask-composite:xor;mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);mask-composite:exclude;opacity:calc(.55 + var(--glass-active)*.45)}
@supports ((backdrop-filter:blur(1px)) or (-webkit-backdrop-filter:blur(1px))){.glass-surface{background:#ffffff80;-webkit-backdrop-filter:blur(22px) saturate(140%);backdrop-filter:blur(22px) saturate(140%)}}
header.glass-surface{max-width:1272px;margin:16px auto 0;padding:17px 28px;border-radius:24px;background:#ffffff66;box-shadow:0 6px 26px #294e3b06,inset 0 1px 0 #ffffffed}
header .logo{font-size:32px}.site-language select{border-radius:12px;background:#ffffff8c;border-color:#ffffffd9;padding:10px 13px;box-shadow:0 2px 9px #2f543c06}
header .plain{border-radius:12px;padding:11px 13px}header .plain:hover{background:#ffffff9c}
.heading{margin:42px 0 30px;gap:32px}.heading h1{letter-spacing:-1.1px;line-height:1.5}.heading .eyebrow{color:#6c8b78;letter-spacing:2px}
.language-pair.glass-surface{border-radius:24px;padding:22px;background:#ffffff72}.language-pair>p{margin-top:13px}
.pair-selectors select{border-radius:12px;border-color:#ffffffdb;background:#ffffffa1;padding:13px 10px;box-shadow:0 2px 6px #214a3505}
.swap-languages{border-color:#ffffffd9;background:#ffffff9c;box-shadow:0 3px 8px #2a513a09;transition:background .2s,transform .35s cubic-bezier(.2,.8,.2,1)}.swap-languages:hover{background:#e0eee4;transform:rotate(8deg)}.swap-languages:active{transform:rotate(8deg) scale(.94)}
.year-bar.glass-surface{border-radius:24px;padding:22px 24px;margin-bottom:18px}.year-tabs{gap:10px;margin-top:15px}.year-tabs button.glass-surface{border-radius:15px;background:#ffffff64;border-color:#ffffffc7;box-shadow:0 3px 7px #294e3b03,inset 0 1px 0 #fff;padding:14px 8px;transition:background .2s,box-shadow .2s,transform .2s}
.year-tabs button small{color:#6c8372}.year-tabs button:hover{background:#ffffffb8;box-shadow:0 7px 16px #294e3b0b;transform:translateY(-2px)}.year-tabs button:active{transform:translateY(0) scale(.98)}
.year-tabs button.selected{background:linear-gradient(150deg,#337866e8,#195747f5);border-color:#347660;box-shadow:0 7px 16px #19574726,inset 0 1px 0 #ffffff40;color:white}.year-tabs button.selected small{color:#dcece1}.year-tabs button.selected::before{background:radial-gradient(ellipse 160px 100px at var(--glass-x) var(--glass-y),#ffffff45,transparent 80%)}
.sound-bar{padding-bottom:20px}.sound-bar #soundOptions.glass-surface{background:linear-gradient(140deg,#327762e8,#195747f5);border-color:#347660;border-radius:14px;padding:12px 18px;box-shadow:0 5px 14px #19574720,inset 0 1px 0 #ffffff40;transition:box-shadow .2s}.sound-bar #soundOptions:hover{box-shadow:0 8px 20px #19574730}
.toolbar{border-bottom:0;margin-bottom:18px;padding-bottom:0}.scene-tabs.glass-surface{padding:6px;border-radius:19px;gap:3px;box-shadow:0 5px 20px #294e3b05}.scene-tabs button{border-radius:13px;color:#60786a;padding:11px 14px;transition:background .2s,box-shadow .2s}.scene-tabs button:hover{background:#ffffffad;color:var(--green)}.scene-tabs button.selected{background:linear-gradient(145deg,#337665,#195747);color:white;border-color:#347660;box-shadow:0 3px 10px #1957471c,inset 0 1px 0 #ffffff30}
.question-controls select{border-radius:12px;background:#ffffff9c;border-color:#ffffffd1;box-shadow:0 3px 12px #294e3b05;padding:11px 12px}.question-controls .outline{border:1px solid #ffffffdb;border-radius:11px;padding:10px 12px;background:#ffffff8c;color:var(--green);box-shadow:0 2px 8px #294e3b05}.question-controls .outline:hover{background:#fff}
.lesson.glass-surface,.metrics.glass-surface,.typing-panel.glass-surface,.last-record.glass-surface,.history.glass-surface,.results.glass-surface{border-radius:24px}.lesson .illustration{background:#dce9d49c}.lesson-content{padding:24px}.lesson .translation{border-radius:0 14px 14px 0;background:#f1f1dd8c;border-left-color:#b5985c}.lesson .context,.lesson .note{color:#657a6c}.lesson #vocab>div{border-color:#cbdcc856}
.metrics.glass-surface{background:#ffffffa6;padding:23px 0;margin-bottom:20px}.metrics>div{border-color:#cdded480}.metrics small{color:#6b8174}.metrics strong{color:#254d3e}
.typing-panel.glass-surface{background:#ffffffc9;min-height:375px}.target{color:#84978a}.target .right{background:#e0eddfb3}.target .current{background:#f3eacbb8}.target .wrong{background:#f9ddd7}textarea{border-radius:16px;border-color:#c2d7c5;background:#f6f9f3c9;box-shadow:inset 0 2px 6px #294e3b04;transition:box-shadow .25s,border-color .25s}textarea:focus{outline:none;border-color:#77a58a;box-shadow:0 0 0 4px #59947813,inset 0 1px 5px #294e3b03}textarea::placeholder{color:#8a9d8f}.panel-top{color:#748b7b}.input-label,#feedback,.input-bottom span{color:#6a8172}
.last-record.glass-surface{position:sticky;background:#dfead570;border-color:#ffffffb3}.last-record>p,.record-context{border-color:#c8d9c880}.listen{background:#ffffff8c;border-color:#ffffffc9;border-radius:12px}.listen:hover{background:#eaf3e6b3}.tip-row p,.mini-guide{color:#758b7b}
.sound-panel.glass-surface{position:fixed;background:#f8fbf1dc;border-radius:28px;box-shadow:0 28px 100px #173c3233,0 2px 8px #173c3210,inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(32px) saturate(150%);backdrop-filter:blur(32px) saturate(150%);border-color:#ffffffed}
.switch-options label{border-color:#ffffffde;background:#ffffff80;border-radius:15px;transition:background .2s,border-color .2s}.switch-options label:hover{background:#fff}.switch-options label:has(input:checked){background:#dfeddacc;border-color:#70977c;box-shadow:inset 0 0 0 1px #70977c}.sound-panel .preview-sounds button{border-radius:12px;background:#e1ecdbb3;border-color:#ffffffc9}.sound-panel .preview-sounds button:hover{background:#d6e6ce}.sound-settings{border-color:#ceddc780}
button,select,a,textarea{-webkit-tap-highlight-color:#2e785522}footer{border-color:#cdded3a6}.plain:hover,.listen-source:hover{color:#0d6747}#toast{border-radius:16px;box-shadow:0 8px 24px #19574720}
@media(min-width:1300px){header.glass-surface{margin-top:20px}}
@media(max-width:1300px){header.glass-surface{margin-left:24px;margin-right:24px}}
@media(max-width:1100px){.last-record.glass-surface{position:static}}
@media(max-width:760px){header.glass-surface{margin:12px 12px 0;padding:13px 16px;border-radius:20px;gap:10px}.site-language select{padding:10px;font-size:11px}.site-language+button{padding:8px 2px;font-size:10px}.heading{margin-top:30px;gap:22px}.language-pair.glass-surface{padding:18px;border-radius:22px}.year-bar.glass-surface{padding:19px 16px;border-radius:22px}.year-tabs{gap:6px}.year-tabs button.glass-surface{border-radius:12px;padding:13px 3px;font-size:11px}.year-tabs button small{font-size:8px}.original-note{right:16px;top:19px;font-size:8px;max-width:39%}.scene-tabs{width:100%}.scene-tabs button{font-size:10px;padding:10px 9px}.scene-tabs.glass-surface{border-radius:17px;padding:5px;gap:3px}.lesson.glass-surface,.metrics.glass-surface,.typing-panel.glass-surface,.last-record.glass-surface{border-radius:21px}.last-record.glass-surface{position:static}.lesson-content{padding:17px}.typing-panel{padding:20px}.metrics>div{padding:0 11px}.sound-panel.glass-surface{border-radius:24px}.liquid-orb{filter:blur(35px);opacity:.45}.liquid-orb--mint{width:300px;height:450px;left:-140px}.liquid-orb--gold{width:300px;right:-150px}.liquid-orb--pearl{display:none}}
@media(hover:none),(pointer:coarse){.liquid-orb{will-change:auto}.glass-surface::before{opacity:.18}.year-tabs button:hover,.swap-languages:hover{transform:none}}
@media(prefers-reduced-motion:reduce){.liquid-orb{will-change:auto;transform:none!important}.glass-surface::before,.glass-surface::after{opacity:.4;transition:none}button,select,textarea{transition:none!important}.year-tabs button:hover,.swap-languages:hover,.swap-languages:active{transform:none}}
@media(prefers-reduced-transparency:reduce){.glass-surface,.language-pair.glass-surface,.typing-panel.glass-surface,.sound-panel.glass-surface{background:#fbfcf8;-webkit-backdrop-filter:none;backdrop-filter:none}.liquid-backdrop{display:none}.year-tabs button.selected,.scene-tabs button.selected,.sound-bar #soundOptions.glass-surface{background:#195747}}

/* A single elastic glass capsule travels between the selected year buttons. */
.year-tabs.has-year-flow{position:relative;isolation:isolate;overflow:clip;padding:3px;margin-left:-3px;margin-right:-3px}
.year-tabs.has-year-flow button.glass-surface{position:relative;z-index:1;transform:none;background:#ffffff35;border-color:#ffffff80;box-shadow:inset 0 1px 0 #ffffffa6;color:var(--green);transition:color .12s,background .18s}
.year-tabs.has-year-flow button.glass-surface:hover{background:#ffffff5c;transform:none;box-shadow:inset 0 1px 0 #ffffffa6}
.year-tabs.has-year-flow button.glass-surface:active{transform:none;background:#ffffff1f}
.year-tabs.has-year-flow button.glass-surface::before{background:radial-gradient(ellipse 160px 100px at var(--glass-x) var(--glass-y),#ffffff26,transparent 80%);opacity:.3}
.year-tabs.has-year-flow button.glass-surface small{color:#708777;transition:color .12s}
.year-tabs.has-year-flow button.glass-surface.liquid-ink{color:#fff;background:transparent;border-color:transparent;box-shadow:none}
.year-tabs.has-year-flow button.glass-surface.liquid-ink small{color:#e1eee4}
.year-tabs.has-year-flow button:focus-visible{outline-offset:-4px}
.year-liquid{position:absolute;left:0;top:0;z-index:0;pointer-events:none;border-radius:16px;transform-origin:50% 50%;background:linear-gradient(155deg,#438e7be8 0%,#286b58f2 47%,#195747 100%);border:1px solid #307760;box-shadow:0 5px 13px #1957472b,inset 0 1px 0 #ffffff6b,inset 0 -2px 3px #0e3e3520;overflow:hidden;will-change:transform;contain:layout paint}
.year-liquid::before{content:"";position:absolute;inset:0;border-radius:inherit;background:radial-gradient(ellipse at 24% 0%,#ffffff5c,transparent 65%),linear-gradient(110deg,transparent 15%,#ffffff17 43%,transparent 72%);box-shadow:inset 0 0 0 1px #ffffff4d}
.year-liquid::after{content:"";position:absolute;left:8%;right:8%;top:1px;height:35%;border-radius:50%;background:linear-gradient(#ffffff1f,transparent);filter:blur(3px)}
.year-tabs[data-flowing=false] .year-liquid{will-change:auto}
@media(max-width:760px){.year-liquid{border-radius:13px}}
@media(prefers-reduced-motion:reduce){.year-tabs.has-year-flow button,.year-tabs.has-year-flow button small{transition:none}.year-liquid{will-change:auto}}
@media(prefers-reduced-transparency:reduce){.year-liquid{background:#195747}}

/* Shared optical material across years, scenes, sound choices and the wheel. */
:root{--liquid-fill:linear-gradient(155deg,#438e7be8 0%,#286b58f2 47%,#195747 100%);--liquid-rim:#307760;--liquid-depth:0 5px 13px #1957472b,inset 0 1px 0 #ffffff6b,inset 0 -2px 3px #0e3e3520}
.year-liquid,.sound-bar #soundOptions.glass-surface,.wheel-band{background:var(--liquid-fill);border:1px solid var(--liquid-rim);box-shadow:var(--liquid-depth)}
.scene-tabs.has-scene-flow{position:relative;isolation:isolate;overflow:clip;padding:6px;gap:3px}
.scene-tabs.has-scene-flow button.glass-surface{position:relative;z-index:1;transform:none;border:1px solid #ffffff80;background:#ffffff35;box-shadow:inset 0 1px 0 #ffffffa6;color:var(--green);transition:color .12s,background .18s}
.scene-tabs.has-scene-flow button.glass-surface:hover{background:#ffffff5c}.scene-tabs.has-scene-flow button.glass-surface.liquid-ink{color:#fff;background:transparent;border-color:transparent;box-shadow:none}
.scene-tabs.has-scene-flow button.glass-surface::before{background:radial-gradient(ellipse 160px 100px at var(--glass-x) var(--glass-y),#ffffff26,transparent 80%);opacity:.3}
.scene-tabs.has-scene-flow button:focus-visible{outline-offset:-4px}.liquid-tabs[data-flowing=false] .liquid-selection{will-change:auto}
.switch-options label:has(input:checked){background:var(--liquid-fill);border-color:var(--liquid-rim);box-shadow:var(--liquid-depth);color:#fff}.switch-options label:has(input:checked) small{color:#e0eee4}
.liquid-light{position:absolute;left:0;top:0;width:440px;height:440px;border-radius:50%;opacity:0;transition:opacity .4s;background:radial-gradient(ellipse,#ffffffe8 0%,#e1f1e485 22%,#c3e6cf26 47%,transparent 71%);will-change:transform}.liquid-backdrop.is-lit .liquid-light{opacity:.85}
@media(hover:hover) and (pointer:fine){body.liquid-pointer-enabled,body.liquid-pointer-enabled *{cursor:url('cursor-dot.svg?v=19.2') 8 8,auto!important}body.liquid-pointer-enabled :is(textarea,input:not([type=checkbox]):not([type=radio]):not([type=range]),[contenteditable=true]){cursor:text!important}body.liquid-pointer-enabled :disabled{cursor:not-allowed!important}}
@media(hover:none),(pointer:coarse){.liquid-light{display:none}}
@media(prefers-reduced-motion:reduce){.liquid-light{display:none}.scene-tabs.has-scene-flow button{transition:none}}
@media(prefers-reduced-transparency:reduce){.year-liquid,.sound-bar #soundOptions.glass-surface,.wheel-band,.switch-options label:has(input:checked){background:#195747}.liquid-light{display:none}}

/* A glass wheel picker with native momentum, snap points and a clear commit. */
.question-controls #questionWheelOpen{display:flex;align-items:center;justify-content:space-between;gap:14px;width:330px;max-width:380px;padding:11px 14px;border:1px solid #ffffffd1;border-radius:13px;background:#ffffff9c;box-shadow:0 3px 12px #294e3b05;color:var(--ink);font:11px 'Noto Sans SC',system-ui,sans-serif;text-align:left;min-height:42px}
.question-wheel-value{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.wheel-chevron{display:block;width:7px;height:7px;border-right:1.5px solid var(--green);border-bottom:1.5px solid var(--green);transform:rotate(45deg);flex-shrink:0;margin:-4px 2px 0 0}
.question-controls #questionWheelOpen:hover{background:#ffffffd9}.question-wheel-open[aria-expanded=true]{box-shadow:0 0 0 3px #5e967c1f!important}
.question-wheel.glass-surface{position:fixed;margin:auto;width:540px;max-width:calc(100vw - 28px);padding:22px;border-radius:28px;overflow:visible;color:var(--ink);background:#f6faf3ef;border-color:#fff;box-shadow:0 25px 100px #143f343b,inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(28px) saturate(140%);backdrop-filter:blur(28px) saturate(140%)}
.question-wheel::backdrop{background:#173d332b;backdrop-filter:blur(5px);-webkit-backdrop-filter:blur(5px)}
.wheel-header{display:flex;align-items:center;justify-content:space-between;gap:14px}.wheel-title{font-size:15px;font-weight:600;margin:0;text-align:center}.wheel-header button{border:0;font:inherit;font-size:12px;border-radius:12px;padding:10px 16px}.wheel-cancel{background:#ffffffa6;color:var(--green)}.wheel-header .wheel-confirm{color:white;background:var(--liquid-fill);box-shadow:var(--liquid-depth);border:1px solid var(--liquid-rim)}
.wheel-caption{font-size:11px;color:#6b8173;text-align:center;margin:22px 0 14px}.wheel-count{display:inline-block;margin-left:12px;padding:3px 10px;background:#e6eedf8c;border-radius:20px;font-size:10px}
.wheel-shell{position:relative;isolation:isolate;border:1px solid #fff;border-radius:20px;background:linear-gradient(110deg,#ffffff5c,#ffffffa6);box-shadow:inset 0 2px 14px #254e3605;overflow:hidden}
.wheel-band{position:absolute;left:8px;right:8px;top:88px;height:44px;border-radius:13px;pointer-events:none;z-index:-1}
.question-wheel-list{height:220px;padding:88px 12px;overflow:auto;scroll-snap-type:y mandatory;scrollbar-width:none;overscroll-behavior:contain;touch-action:pan-y;mask-image:linear-gradient(transparent,#000 30%,#000 70%,transparent);-webkit-mask-image:linear-gradient(transparent,#000 30%,#000 70%,transparent);outline:none}
.question-wheel-list::-webkit-scrollbar{display:none}.question-wheel-list:focus-visible{outline:2px solid #6c9c7b;outline-offset:-3px;border-radius:20px}
.wheel-option{height:44px;line-height:44px;scroll-snap-align:center;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-align:center;padding:0 12px;font-size:15px;color:#5b7b68;opacity:.22;transform:perspective(600px) rotateX(var(--wheel-angle,0deg)) scale(var(--wheel-scale,.9));transform-origin:center;user-select:none}
.wheel-option.is-current{color:#fff;font-weight:500}.wheel-hint{text-align:center;font-size:10px;color:#778d7c;margin:17px 0 0;letter-spacing:.2px}
@media(max-width:760px){.question-controls #questionWheelOpen{width:100%;max-width:100%;margin-top:8px}.question-wheel.glass-surface{width:calc(100vw - 20px);max-width:540px;margin:auto auto max(10px,env(safe-area-inset-bottom));padding:18px 14px;border-radius:27px}.wheel-title{font-size:14px}.wheel-option{font-size:13px}.wheel-header button{padding:9px 13px}.wheel-caption{margin-top:18px}}
@media(prefers-reduced-motion:reduce){.wheel-option{transform:none!important}.question-wheel-list{scroll-behavior:auto}}
@media(prefers-reduced-transparency:reduce){.question-wheel.glass-surface{background:#f8fbf5}}

/* Glass language choices unfold above/below; selected words dissolve in place. */
.language-picker{position:relative;min-width:0}.language-pair:has(.language-picker.is-open){z-index:45}
.language-picker-button{display:flex;align-items:center;justify-content:space-between;gap:14px;width:100%;min-height:44px;min-width:0;padding:12px 11px;border:1px solid #ffffffdb;border-radius:13px;background:#ffffffa1;color:var(--green);font:500 12px system-ui,sans-serif;box-shadow:0 2px 6px #214a3505;text-align:left}
.language-picker-button:hover{background:#ffffffc9}.language-picker-button:focus-visible{outline:2px solid #629a7e;outline-offset:3px}.language-picker-button[aria-expanded=true]{box-shadow:0 0 0 3px #5e967c1f}
.language-picker-value{position:relative;display:block;min-width:0;width:100%;height:20px;line-height:20px;overflow:hidden}.language-value-line{position:absolute;inset:0;display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;transform-origin:50% 50%}
.language-options.glass-surface{position:absolute;left:var(--options-left,-8px);top:var(--options-top,0px);z-index:70;min-width:100%;width:calc(100% + 16px);max-width:calc(100vw - 48px);padding:8px;display:grid;gap:5px;background:#f4faf2ed;border:1px solid #ffffffed;border-radius:20px;box-shadow:0 16px 45px #214a3526,inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(28px) saturate(145%);backdrop-filter:blur(28px) saturate(145%);transform-origin:center}
.language-picker.is-open .language-picker-button{opacity:0;pointer-events:none}
.language-option{position:relative;z-index:2;width:100%;height:var(--option-height,44px);min-height:var(--option-height,44px);border:1px solid #ffffffc9;border-radius:12px;background:#ffffff70;color:var(--green);padding:10px 12px;font:500 12px system-ui,sans-serif;text-align:left;transform:perspective(400px) rotateX(var(--option-tilt,0deg));transition:background .18s,transform .2s;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.language-option:hover{background:#fff;transform:perspective(400px) rotateX(0) scale(1.015)}.language-option.is-selected{background:var(--liquid-fill);border-color:var(--liquid-rim);box-shadow:var(--liquid-depth);color:white}.language-option:focus-visible{outline:2px solid #629a7e;outline-offset:1px}
@media(max-width:760px){.language-picker-button{font-size:11px;padding:10px 8px;gap:8px;min-height:42px}.language-picker-value{height:19px;line-height:19px}.language-options.glass-surface{width:calc(100% + 16px)}.language-option{font-size:12px}}
@media(prefers-reduced-motion:reduce){.language-options.glass-surface{animation:none}.language-option,.language-option:hover{transform:none;transition:none}}
@media(prefers-reduced-transparency:reduce){.language-options.glass-surface{background:#f8fbf5}}

/* Swap the actual visible glass slots on two opposing arcs. */
.language-pair.is-swapping{z-index:46}.language-pair.is-swapping .language-picker-button{opacity:0;pointer-events:none}
.language-swap-flight{position:absolute;z-index:80;display:flex;align-items:center;gap:14px;padding:12px 11px;border:1px solid #ffffffed;border-radius:13px;background:linear-gradient(135deg,#fffffff2,#f0f8edc9);box-shadow:0 8px 22px #1e573126,inset 0 1px 0 #fff;color:var(--green);font:500 12px system-ui,sans-serif;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;pointer-events:none;will-change:transform,width;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}
@media(max-width:760px){.language-swap-flight{font-size:11px;padding:10px 8px}}
@media(prefers-reduced-motion:reduce){.language-swap-flight{display:none}}

/* Sound cards share the travelling glass selection, including their native radios. */
.switch-options.has-switch-flow{position:relative;isolation:isolate}
.switch-options.has-switch-flow label,.switch-options.has-switch-flow label:has(input:checked){position:relative;z-index:1;background:#ffffff45;border:1px solid #ffffffb3;box-shadow:inset 0 1px 0 #ffffffd1;color:var(--green);transition:background .18s,color .12s,transform .14s}
.switch-options.has-switch-flow label:hover{background:#ffffff91}.switch-options.has-switch-flow label:active{transform:scale(.985)}
.switch-options.has-switch-flow label small,.switch-options.has-switch-flow label:has(input:checked) small{color:#748b79;transition:color .12s}
.switch-options.has-switch-flow label.liquid-ink,.switch-options.has-switch-flow label.liquid-ink:has(input:checked){background:transparent;border-color:transparent;box-shadow:none;color:#fff}
.switch-options.has-switch-flow label.liquid-ink small,.switch-options.has-switch-flow label.liquid-ink:has(input:checked) small{color:#e1eee4}.switch-options.has-switch-flow .liquid-selection{border-radius:15px}

/* Native, keyboard-accessible range with a frosted track and a glass lens thumb. */
.sound-settings #soundVolume{--volume-fill:35%;appearance:none;-webkit-appearance:none;background:transparent;height:30px;padding:0;accent-color:var(--green);border-radius:20px;outline:none}
.sound-settings #soundVolume::-webkit-slider-runnable-track{height:8px;border:1px solid #ffffffd9;border-radius:12px;background:linear-gradient(to right,#3c8065b3 0%,#5d9b7dcc var(--volume-fill),#ffffff80 var(--volume-fill),#edf4e9b3 100%);box-shadow:inset 0 1px 3px #204d3721,0 1px 0 #fff}
.sound-settings #soundVolume::-webkit-slider-thumb{appearance:none;-webkit-appearance:none;width:26px;height:24px;margin-top:-9px;border:1px solid #ffffffed;border-radius:12px;background:linear-gradient(155deg,#fffffff2 0%,#f4fff4b3 42%,#c6e1cfbd 100%);box-shadow:0 3px 9px #1d533435,inset 0 1px 0 #fff,inset 0 -2px 3px #96b9a22b;transition:transform .16s,box-shadow .16s}
.sound-settings #soundVolume:active::-webkit-slider-thumb{transform:scale(1.12);box-shadow:0 5px 13px #1d533440,inset 0 1px 0 #fff}
.sound-settings #soundVolume::-moz-range-track{height:7px;border:1px solid #ffffffd9;border-radius:12px;background:#ffffff91;box-shadow:inset 0 1px 3px #204d3721}
.sound-settings #soundVolume::-moz-range-progress{height:7px;border-radius:12px;background:linear-gradient(90deg,#3c8065b3,#5d9b7dcc)}
.sound-settings #soundVolume::-moz-range-thumb{width:26px;height:24px;border:1px solid #ffffffed;border-radius:12px;background:linear-gradient(155deg,#fffffff2,#c6e1cfbd);box-shadow:0 3px 9px #1d533435,inset 0 1px 0 #fff;transition:transform .16s}
.sound-settings #soundVolume:active::-moz-range-thumb{transform:scale(1.12)}.sound-settings #soundVolume:focus-visible{outline:3px solid #70a48b55;outline-offset:3px}

/* Question order uses the same anchored glass menu and dissolving label. */
.question-controls:has(.language-picker.is-open){position:relative;z-index:45}
.language-picker--order{min-width:132px}.language-picker--order .language-picker-button{min-height:42px;padding:10px 12px;font:11px 'Noto Sans SC',system-ui,sans-serif}
.language-picker--order .language-options{max-width:220px}.language-picker--order .language-option{font:11px 'Noto Sans SC',system-ui,sans-serif;padding:10px 12px}
@media(prefers-reduced-motion:reduce){.switch-options.has-switch-flow label{transition:none}.sound-settings #soundVolume::-webkit-slider-thumb{transition:none}.sound-settings #soundVolume::-moz-range-thumb{transition:none}.sound-settings #soundVolume:active::-webkit-slider-thumb{transform:none}.sound-settings #soundVolume:active::-moz-range-thumb{transform:none}.switch-options.has-switch-flow label:active{transform:none}}

/* The expanded glass surface closes into the original slot; labels stay still. */
.language-pair:has(.language-picker.is-merging),.question-controls:has(.language-picker.is-merging){position:relative;z-index:45}
.language-picker.is-merging .language-picker-button{position:relative;z-index:72;background:#ffffffe6;box-shadow:0 0 17px #c6e7d54d,inset 0 1px 0 #fff}
.language-merge-shell{position:absolute;z-index:70;display:grid;grid-auto-rows:var(--option-height,44px);gap:5px;padding:8px;border:1px solid #ffffffed;border-radius:20px;background:linear-gradient(135deg,#f8fff2f0,#eaf5e4d9);box-shadow:0 10px 30px #214a351c,inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(24px) saturate(145%);backdrop-filter:blur(24px) saturate(145%);overflow:hidden;pointer-events:none;transform:none;will-change:left,top,width,height,opacity}
.language-merge-shell *{pointer-events:none!important}.language-merge-shell .language-option{transition:none;transform:none}
@media(prefers-reduced-motion:reduce){.language-merge-shell{display:none}}

.language-merge-content{position:absolute;z-index:71;display:grid;grid-auto-rows:var(--option-height,44px);gap:5px;padding:8px;border:1px solid transparent;border-radius:20px;background:transparent;overflow:hidden;pointer-events:none;transform:none}
.language-merge-content *{pointer-events:none!important}.language-merge-content .language-option{transition:none;transform:none}
@media(prefers-reduced-motion:reduce){.language-merge-content{display:none}}
.language-picker-button{transition:background .28s,box-shadow .28s}