:root{--paper:#f5f2e9;--panel:#fffef9;--ink:#223b35;--muted:#69746a;--teal:#245f50;--orange:#c94a24;--line:#dedfd3;--soft:#edeedf;--serif:"Iowan Old Style","Palatino Linotype","Songti SC","STSong",serif;--sans:"Avenir Next","PingFang SC","Microsoft YaHei",sans-serif;--numeric:"Baskerville","Iowan Old Style",Georgia,serif}
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#cdd2c6}.wordmark{display:flex;align-items:center;gap:13px;color:var(--ink);text-decoration:none;font-size:22px;font-weight:650;letter-spacing:3px}.wordmark small{display:block;font-size:8px;letter-spacing:1.7px;margin-top:5px;font-weight:600}.brand-icon{background:var(--teal);color:var(--panel);height:45px;width:45px;display:flex;justify-content:center;align-items:center;transform:rotate(-7deg);border-radius:9px;font-family:var(--numeric);font-size:30px;letter-spacing:-2px;font-weight:500}.brand-icon>span{color:#efb75e}.text-button{border:0;background:none;font-size:13px;display:flex;gap:8px;align-items:center;min-height:44px}.text-button:hover{color:var(--orange)}.circle-icon{width:18px;height:18px;border:1.4px solid currentColor;border-radius:50%;font-family:var(--serif);display:inline-grid;place-items:center;font-size:13px}.intro{display:flex;justify-content:space-between;align-items:center;padding:46px 0 38px}.eyebrow{font-size:11px;letter-spacing:2px;color:var(--teal);display:flex;align-items:center;gap:9px;font-weight:600}.eyebrow>span{height:6px;width:6px;background:var(--orange);border-radius:50%}h1{font-family:var(--serif);font-weight:600;font-size:44px;letter-spacing:1px;line-height:1.45;margin:10px 0 10px}.title-accent{position:relative;color:var(--teal);display:inline-block}.underline{position:absolute;width:100%;height:9px;border-top:3px solid var(--orange);border-radius:50%;bottom:0;left:0;transform:rotate(-3deg)}.intro p{color:var(--muted);margin:0;font-size:13px;letter-spacing:.8px}.intro-stamp{transform:rotate(10deg);text-align:center;border:1px solid #a4b2a5;border-radius:50%;width:112px;height:112px;display:flex;flex-direction:column;justify-content:center;margin-right:18px;color:var(--teal)}.intro-stamp>span{font-size:8px;letter-spacing:1.4px}.intro-stamp strong{font:italic 40px/1.35 var(--numeric)}.mobile-break{display:none}.play-layout{display:grid;grid-template-columns:minmax(0,1fr) 304px;gap:24px}.game-panel{background:var(--panel);border:1px solid #d8ddd0;border-radius:18px;overflow:hidden;box-shadow:0 6px 0 #e5e5d9}.panel-top{padding:20px 24px;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;gap:12px}.difficulty{background:#eeefe6;padding:4px;border-radius:9px;display:flex;gap:3px}.difficulty button{border:0;background:transparent;border-radius:6px;padding:10px 15px;font-size:12px;white-space:nowrap;min-height:40px}.difficulty button[aria-pressed=true]{background:var(--teal);color:white;box-shadow:0 2px 4px #153d2a25}.difficulty button:hover:not([aria-pressed=true]){background:#e0e6d7}.round-label{font-size:10px;letter-spacing:1.4px;color:var(--muted);white-space:nowrap}.board{padding:23px 30px 0;text-align:center;min-height:347px}.board-heading{display:flex;justify-content:space-between;align-items:center;color:var(--muted);font-size:11px;gap:8px}.timer{display:flex;align-items:center;gap:6px;font-variant-numeric:tabular-nums;font-size:12px}.timer svg{width:16px;height:16px}.target-label{color:var(--muted);font-size:12px;letter-spacing:2px;margin:25px 0 20px}.target-label strong{font-family:var(--numeric);font-size:24px;line-height:1;letter-spacing:0;color:var(--orange);vertical-align:-2px;padding-left:5px}.cards{display:flex;gap:15px;justify-content:center;min-height:117px;align-items:center}.number-card{background:#f4f3e9;border:1px solid #d8ddcc;box-shadow:0 5px 0 #e4e5d8;border-radius:12px;width:103px;height:112px;position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;}.number-card:hover:not(:disabled){background:#e7eddf;transform:translateY(-3px);box-shadow:0 8px 0 #dce0cf}.number-card[aria-pressed=true]{background:var(--teal);color:white;border-color:var(--teal);box-shadow:0 5px 0 #184737}.number-card .card-value{font:56px/1 var(--numeric);letter-spacing:-1px}.number-card .card-value.fraction-value{font-size:35px}.card-corner{position:absolute;top:9px;left:11px;font-size:9px;opacity:.65}.card-corner:last-child{top:auto;left:auto;bottom:8px;right:10px;transform:rotate(180deg)}.number-card .card-expression{max-width:95%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;font-size:9px;margin-top:7px}.number-card.won{background:#ecb95e;border-color:#d7a451;color:var(--ink);box-shadow:0 5px 0 #dab365}.selection-line{height:44px;padding-top:18px;font-size:12px;color:var(--teal)}.operators{display:flex;justify-content:center;gap:13px;margin-top:10px}.operators button{width:50px;height:46px;font-size:25px;font-family:var(--sans);background:var(--panel);border:1px solid #d6dace;border-radius:8px;line-height:1}.operators 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span:nth-child(3){left:15px;bottom:0;transform:rotate(-20deg)}.math-doodle span:nth-child(4){right:0;bottom:-5px;transform:rotate(15deg)}.empty-history p{font-size:12px;margin:0 0 8px;color:var(--muted)}.empty-history small{font-size:10px;color:var(--muted)}.answer-button{margin-top:auto;display:flex;justify-content:space-between;align-items:center;text-align:left;min-height:50px;border:0;border-top:1px dashed #d7dcce;background:transparent;width:100%;font-size:11px;color:var(--muted)}.answer-button:hover{color:var(--orange)}.history{list-style:none;padding:0;margin:16px 0;display:flex;flex-direction:column;gap:12px}.history:empty{display:none}.history li{display:flex;align-items:center;gap:12px;background:#f0f1e6;padding:12px 10px;border-radius:8px;animation:appear .25s ease-out;font-size:14px;font-variant-numeric:tabular-nums}.step-number{border:1px solid #cbd2c0;border-radius:50%;font-size:10px;min-width:23px;height:23px;display:grid;place-items:center;color:var(--muted)}.history 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#cdd2c6}.how-tag{margin-left:auto;font-size:10px;color:var(--teal)}footer{border-top:1px solid #cdd2c6;padding:22px 0 26px;display:flex;justify-content:space-between;font-size:10px;letter-spacing:.6px;color:var(--muted)}.footer-dot{margin:0 7px}dialog{border:1px solid var(--line);border-radius:18px;box-shadow:0 20px 80px #102e3433;padding:26px;width:min(440px,calc(100% - 32px));background:var(--panel);color:var(--ink)}dialog::backdrop{background:#16352c66;backdrop-filter:blur(4px)}.modal-heading{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px}.modal-heading h2{font-family:var(--serif);font-size:25px;margin:0}.modal-heading button{border:0;background:none;min-width:44px;min-height:44px;font-size:26px}.modal-done{width:100%;margin-top:20px}#modal-content{font-size:14px;line-height:1.9;color:var(--muted)}#modal-content ol{padding-left:22px}#modal-content .solution-step{background:var(--soft);padding:8px 14px;margin:9px 0;border-radius:7px;color:var(--teal);font-size:19px}.confetti{position:fixed;left:var(--x);top:-20px;width:9px;height:15px;background:var(--color);pointer-events:none;z-index:10;animation:confetti 2s ease-in var(--delay) forwards}@keyframes deal{from{opacity:0;transform:translateY(10px) rotate(-3deg)}to{opacity:1;transform:none}}@keyframes appear{from{opacity:0;transform:translateY(5px)}to{opacity:1;transform:none}}@keyframes confetti{to{transform:translateY(105vh) rotate(650deg);opacity:0}}
@media(min-width:1400px){.site-shell{padding-top:12px}.intro{padding-top:55px;padding-bottom:45px}.board{padding-top:27px;padding-bottom:8px}.cards{margin:8px 0}.target-label{margin-top:29px}.site-header{height:106px}}
@media(max-width:1050px){.site-shell{padding:0 30px}.play-layout{grid-template-columns:minmax(0,1fr) 270px;gap:18px}.panel-top{padding:16px}.difficulty button{padding:8px 10px}.round-label{font-size:9px;letter-spacing:.4px}.board{padding:22px 20px 0}.cards{gap:10px}.number-card{width:83px;height:103px}.number-card .card-value{font-size:49px}.game-toolbar{padding:14px 16px}.utility-group{gap:9px}.next-button{padding:12px 14px}.utility{font-size:11px}.utility svg{width:15px}.how-to{gap:12px}.how-tag{width:100%;margin-left:0}.intro h1{font-size:38px}}
@media(max-width:800px){.site-shell{max-width:660px;padding:0 22px}.site-header{height:88px}.intro{padding:32px 0}.intro-stamp{width:85px;height:85px;margin-right:3px}.intro-stamp strong{font-size:30px}.intro-stamp>span{font-size:6px}.intro h1{font-size:35px}.intro p{font-size:11px;letter-spacing:0}.play-layout{grid-template-columns:1fr;gap:22px}.panel-top{padding:16px 20px}.difficulty button{padding:8px 14px}.board{padding:23px 25px 0}.number-card{width:101px;height:110px}.number-card .card-value{font-size:55px}.cards{gap:14px}.game-toolbar{padding:14px 20px}.utility-group{gap:16px}.utility{font-size:12px}.utility svg{width:17px}.side-column{display:grid;grid-template-columns:1fr 1fr;gap:14px}.journey-panel{grid-row:span 2;min-height:240px;padding:19px 17px 0}.stats-panel{padding:18px 16px;gap:8px}.stats-panel>div+div{padding-left:12px}.little-note{padding:0 4px;gap:8px}.little-note p{font-size:10px}.little-note>span{font-size:27px}.math-doodle{height:45px;width:70px;margin-bottom:8px}.math-doodle span{font-size:25px}.empty-history{padding:12px 0}.how-to{padding-top:26px;gap:10px 15px}.how-to p{font-size:11px}.how-separator{display:none}.how-tag{width:auto;margin-left:auto}}
@media(max-width:540px){.site-shell{padding:0 18px}.wordmark{font-size:20px;gap:11px}.brand-icon{width:40px;height:40px;font-size:28px}.wordmark small{font-size:6px}.text-button{font-size:11px;gap:5px}.intro{position:relative;padding:27px 0 28px}.eyebrow{font-size:9px;letter-spacing:1.4px}.intro h1{font-size:36px;line-height:1.45;margin:10px 0}.mobile-break{display:block}.intro-stamp{position:absolute;right:0;top:48px;width:75px;height:75px}.intro-stamp strong{font-size:27px}.intro-stamp>span{font-size:5px}.intro p{font-size:10px}.panel-top{padding:12px;gap:7px}.difficulty{padding:3px;gap:1px}.difficulty button{font-size:11px;padding:8px 10px;min-height:38px}.round-label{font-size:8px;letter-spacing:0}.board{padding:19px 14px 0;min-height:342px}.board-heading{font-size:9px}.timer{font-size:11px}.cards{gap:9px}.number-card{width:calc((100% - 27px)/4);max-width:90px;height:102px;border-radius:9px}.number-card .card-value{font-size:48px}.number-card .card-value.fraction-value{font-size:26px}.card-corner{font-size:8px;left:8px}.target-label{margin:25px 0 20px}.selection-line{font-size:11px}.board-help{font-size:9px}.board-help span{margin:0 5px}.operators{gap:12px}.operators button{height:44px;width:48px}.game-toolbar{padding:12px;gap:8px}.utility-group{gap:10px}.utility{font-size:10px;gap:4px}.utility svg{width:15px}.next-button{font-size:11px;padding:11px 12px}.next-button>span{padding-left:9px}.side-column{grid-template-columns:1fr}.journey-panel{grid-row:auto;min-height:230px}.section-heading{padding-bottom:5px}.stats-panel{padding:19px 23px;gap:20px}.stats-panel>div+div{padding-left:25px}.little-note{display:none}.history{gap:8px}.history li{padding:9px 12px}.how-to{gap:12px;font-size:10px}.how-label{width:100%;border:0;padding:0}.how-to p{font-size:10px}.how-tag{margin:0;width:100%;font-size:10px}footer{font-size:9px;letter-spacing:0;padding:20px 0}dialog{padding:22px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}.confetti{display:none}}

.number-card.dealing{animation:deal .35s both;animation-delay:calc(var(--i)*45ms)}
.header-actions{display:flex;align-items:center;gap:20px}.friend-link{font-size:13px;color:var(--teal);text-decoration:none;min-height:44px;display:flex;align-items:center;font-weight:600}@media(max-width:540px){.header-actions{gap:12px}.friend-link{font-size:11px}.header-actions .circle-icon{display:none}.header-actions .text-button{font-size:10px}.wordmark small{letter-spacing:1px}}