@import "https://fonts.googleapis.com/css2?family=Baloo+2:wght@500;700;800&family=Ma+Shan+Zheng&family=Nunito:wght@500;700;900&display=swap";:root{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--ink:#2e2a20;--muted:#786f5c;--paper:#fff8df;--paper-line:#5884a62e;--paper-edge:#ead7a8;--wood:#d8a864;--wood-dark:#9e6837;--cream:#fffdf0;--green:#5e9f74;--green-dark:#376f4d;--blue:#4a8ec3;--red:#e86f5a;--yellow:#f4c34e;--pink:#f4a7ad;--shadow:#50321433;--soft-shadow:#5032141c;--radius:24px;--radius-sm:16px;--container:1180px;background:#f1d59b;font-family:Nunito,PingFang SC,Microsoft YaHei,sans-serif}*{box-sizing:border-box}body{min-width:320px;min-height:100vh;color:var(--ink);-webkit-font-smoothing:antialiased;text-rendering:optimizelegibility;background:radial-gradient(circle at 10% 8%,#fff8d2e6 0 120px,#0000 121px),radial-gradient(circle at 90% 18%,#71a4c452 0 180px,#0000 181px),linear-gradient(120deg,#f4dcaa 0%,#dfb36d 52%,#c99a55 100%);margin:0}body:before{z-index:-1;content:"";opacity:.28;pointer-events:none;background-image:linear-gradient(90deg,#65401e2e 1px,#0000 1px),linear-gradient(#ffffff1f 1px,#0000 1px);background-size:54px 54px;position:fixed;inset:0}button,input{font:inherit}button{min-height:44px;color:var(--ink);cursor:pointer;touch-action:manipulation;border:0;transition:transform .14s,box-shadow .14s,background .14s}button:hover:not(:disabled){transform:translateY(-2px)}button:active:not(:disabled){transform:translateY(1px)}button:disabled{cursor:not-allowed;opacity:.55}button:focus-visible,input:focus-visible{outline-offset:3px;outline:4px solid #4a8ec340}.app-shell{width:min(var(--container), calc(100% - 28px));margin:0 auto;padding:28px 0 44px}.hero-panel{background:linear-gradient(var(--paper-line) 1px, transparent 1px) 0 54px / 100% 34px, radial-gradient(circle at 86% 18%, #f4c34e6b 0 78px, transparent 79px), linear-gradient(135deg, #fff9de 0%, #fff0bd 100%);min-height:260px;box-shadow:0 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Zheng,"Baloo 2",cursive;font-size:clamp(4rem,11vw,8.8rem);font-weight:400;line-height:.92}.hero-copy p:last-child{max-width:650px;color:var(--muted);margin:22px 0 0;font-size:clamp(1.06rem,2vw,1.3rem);font-weight:800}.island-badge{z-index:1;aspect-ratio:1;min-width:142px;box-shadow:0 16px 26px var(--soft-shadow), inset 0 -8px 0 #d8a8642e;background:linear-gradient(145deg,#fffdf0,#ffe39c);border:4px solid #9e683747;border-radius:32px 42px 34px 48px;place-items:center;padding:16px;display:grid;position:relative;transform:rotate(3deg)}.island-badge span,.island-badge small{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;font-family:"Baloo 2",sans-serif;font-weight:800}.island-badge strong{font-family:"Baloo 2",sans-serif;font-size:3.6rem;line-height:.85}.mode-tabs{box-shadow:0 16px 32px var(--soft-shadow);background:#fffdf0c2;border:3px solid #9e68372e;border-radius:30px;grid-template-columns:repeat(3,1fr);gap:12px;margin:20px 0;padding:12px;display:grid}.mode-tabs 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0;font-size:1.18rem;font-weight:900}.number-pad{background:linear-gradient(145deg,#fffdf0eb,#ffefc2db);border-radius:30px;gap:14px;padding:18px;display:grid}.digit-grid{grid-template-columns:repeat(5,1fr);gap:12px;display:grid}.digit-grid button{min-height:76px;color:var(--ink);background:#fffdf9;border-radius:22px;font-family:"Baloo 2",sans-serif;font-size:2.35rem;font-weight:800;box-shadow:inset 0 -7px #9e683724,0 6px #9e68371f}.digit-grid button:nth-child(3n+1){color:var(--red)}.digit-grid button:nth-child(3n+2){color:var(--green-dark)}.digit-grid button:nth-child(3n){color:var(--blue)}.pad-actions,.difficulty-row,.switch-row,.operation-row{flex-wrap:wrap;gap:10px;display:flex}.primary,.secondary,.next-button,.mistake-item button{border-radius:18px;padding:12px 20px;font-weight:900}.primary,.next-button,.mistake-item button{color:#fffdf0;background:linear-gradient(135deg, var(--red), #cf5947);box-shadow:0 8px #91413038}.secondary{background:#fffdf9;box-shadow:inset 0 0 0 2px 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p{max-width:480px;color:var(--muted);font-weight:800}.mistake-list{gap:12px;display:grid}.mistake-item{background:#ffffff8c;border-radius:22px;grid-template-columns:1fr auto auto;align-items:center;gap:12px;padding:15px;display:grid}.mistake-item strong{font-family:"Baloo 2",sans-serif;font-size:1.42rem}.mistake-item span{color:var(--muted);font-weight:900}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important}}@media (width<=900px){.hero-panel,.adventure-layout{grid-template-columns:1fr}.island-badge{justify-self:start}.stats-ribbon,.digit-grid,.range-grid{grid-template-columns:repeat(2,1fr)}.mistake-item{grid-template-columns:1fr}}@media (width<=560px){.app-shell{width:min(100% - 18px, 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