@font-face{font-family:LocalFallback;src:local('PingFang SC')}*{box-sizing:border-box}html{color-scheme:light}body{margin:0;background:#f7f6f2;color:#292b35;font-family:LocalFallback,'PingFang SC','Microsoft YaHei',system-ui,sans-serif;font-size:15px;-webkit-tap-highlight-color:transparent}button,input,select{font:inherit}button,a,input,select{touch-action:manipulation}button{cursor:pointer}button:disabled{opacity:.5;cursor:wait}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #9b8bd4;outline-offset:3px}button{color:inherit;border:0}a{color:inherit;text-decoration:none}.header{height:96px;max-width:1240px;padding:0 36px;margin:auto;display:flex;align-items:center;justify-content:space-between;gap:22px}.brand{display:flex;align-items:center;gap:11px;font-size:23px;font-weight:850;letter-spacing:1px;white-space:nowrap}.brand small{display:block;font-size:10px;letter-spacing:2px;color:#91918f;font-weight:500;margin-top:3px}.brandmark{background:#f38450;color:white;width:43px;height:46px;border-radius:13px 13px 13px 4px;display:grid;place-items:center;font-size:25px;transform:rotate(-5deg)}nav{display:flex;gap:5px}nav button{background:transparent;padding:12px 16px;border-radius:30px;color:#7a7b7b;font-size:14px;white-space:nowrap}nav button span{margin-right:6px}nav button.active{background:#fff;color:#252832;box-shadow:0 2px 7px #00000005}nav button.active span{color:#eb8050}.history-button{background:transparent;color:#777;font-size:14px}#main{max-width:1168px;margin:16px auto 0;padding:0 24px;min-height:calc(100vh - 210px)}.hero{border-radius:26px;background:#eeeaf5;min-height:222px;position:relative;overflow:hidden;padding:38px 44px;display:flex;align-items:center;justify-content:space-between}.eyebrow{color:#7c7395;font-size:11px;letter-spacing:2px;font-weight:650}.hero h1{font-size:34px;letter-spacing:1px;margin:13px 0 11px;font-weight:800}.hero h1 em{font-style:normal;color:#8b77b3;position:relative}.hero h1 em:after{content:'';position:absolute;height:5px;background:#c1b2dc;bottom:-7px;left:0;right:0;border-radius:50%}.hero p{color:#85808f;font-size:14px;line-height:1.9;margin:0}.hero-art{position:relative;width:310px;height:170px;margin-right:25px;flex-shrink:0}.math-sheet{position:absolute;left:80px;top:4px;transform:rotate(-9deg);width:144px;height:168px;background:#fffdf8;border:3px solid #d7cce9;border-radius:17px;box-shadow:7px 9px 0 #ddd4e9;padding:23px 16px;font-family:Georgia,serif;font-size:23px;color:#655781;line-height:1.65}.math-sheet b{color:#e88d61;font-size:29px}.math-orbit{position:absolute;border-radius:18px;display:grid;place-items:center;font-size:32px;font-weight:800;width:58px;height:58px}.orbit-one{background:#f6d08d;left:10px;top:66px;transform:rotate(-16deg);color:#a67629}.orbit-two{background:#d7e3d9;right:8px;top:14px;transform:rotate(14deg);color:#7a9b7a}.orbit-three{color:#a194b9;right:15px;bottom:7px;font-size:45px}.art-star{position:absolute;color:#b9aad1;left:35px;top:4px;font-size:29px}.content-grid{display:grid;grid-template-columns:minmax(0,1fr) 286px;gap:24px;margin-top:26px}.card{background:#fff;border:1px solid #eeede7;border-radius:22px;padding:27px 29px}.card-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:23px}.card-heading h2{font-size:19px;margin:0;font-weight:750}.step{background:#f3eee8;color:#a59076;border-radius:6px;font-size:11px;padding:5px 8px;letter-spacing:1px}.tabs{display:flex;background:#f5f5f1;padding:5px;border-radius:12px;gap:3px;margin-bottom:25px}.tabs button{flex:1;padding:11px 6px;background:transparent;border-radius:9px;font-size:13px;color:#858580}.tabs button.active{background:white;box-shadow:0 2px 5px #00000006;color:#3b3d42;font-weight:650}.field-label{display:block;font-size:13px;font-weight:650;margin:0 0 11px}.field-label .muted{font-weight:400;font-size:11px;margin-left:8px}.grade-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:8px}.chip{padding:12px 4px;background:#fff;border:1px solid #e7e7e2;border-radius:10px;font-size:13px;color:#777975}.chip.active{color:#cf7448;background:#fff2e8;border-color:#edb99a;font-weight:650}.term-row{display:flex;gap:10px;margin-top:11px}.term-row .chip{padding:10px 25px}.notice{font-size:12px;line-height:1.8;color:#93948f;margin-top:12px}.topic-note{display:flex;align-items:center;gap:7px;color:#799184;background:#f3f7f3;border-radius:9px;padding:10px 13px;font-size:12px;margin:17px 0 0}.divider{height:1px;background:#f0f0ea;margin:24px 0}.choice-row{display:flex;gap:9px;flex-wrap:wrap}.choice-row .chip{min-width:64px;padding:10px 15px}.choice-row .chip.active{background:#f1edf8;color:#8771ad;border-color:#c8b9df}.inline-number{width:74px;border:1px solid #e6e6e1;border-radius:10px;padding:10px;color:#666;background:#fff;text-align:center}.two-fields{display:grid;grid-template-columns:1fr 1fr;gap:20px}.field input,.field select{width:100%;border:1px solid #e5e5df;border-radius:10px;padding:11px 12px;background:#fff;color:#555}.field input[type=checkbox]{width:auto}.select{border:1px solid #e5e5df;border-radius:10px;padding:11px 12px;background:#fff;color:#555;width:100%}.type-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:9px}.type-option{text-align:left;border:1px solid #e8e8e1;border-radius:11px;padding:13px 12px;background:white}.type-option.active{background:#fff2e8;border-color:#edb99a;color:#b96c44}.type-option small{display:block;font-size:10px;color:#9c9c95;margin-top:6px}.checks{display:flex;flex-wrap:wrap;gap:20px;margin-top:17px;font-size:12px;color:#7f817b}.checks label{display:flex;align-items:center;gap:6px}.checks input{accent-color:#d9875c}.primary{background:#eb8655;color:white;border-radius:12px;padding:15px 22px;font-weight:650;font-size:14px;box-shadow:0 4px 0 #d878480f;display:inline-flex;gap:12px;align-items:center;justify-content:center}.primary.wide{width:100%;margin-top:25px}.primary:hover{background:#df794a}.secondary{background:#f1eee8;color:#777468;border-radius:11px;padding:12px 18px;display:inline-flex;align-items:center;justify-content:center;gap:8px}.start-foot{display:flex;align-items:center;justify-content:center;gap:7px;color:#aaa99f;font-size:11px;margin-top:13px}.side-card{border-radius:22px;padding:24px;margin-bottom:18px}.daily{background:#fff3e0;border:1px solid #f1e6d0;position:relative;overflow:hidden}.side-title{font-size:13px;font-weight:700;display:flex;align-items:center;gap:7px}.daily h3{font-size:23px;margin:18px 0 10px;line-height:1.5}.daily p,.side-card p{font-size:12px;color:#99907b;line-height:1.9}.sun{position:absolute;right:19px;top:15px;font-size:39px;color:#e7b65b;transform:rotate(15deg)}.side-link{font-size:12px;background:transparent;padding:10px 0 0;color:#b78e4e}.shortcut{background:#fff;border:1px solid #eeede7}.shortcut-item{display:flex;gap:12px;width:100%;align-items:center;background:transparent;text-align:left;padding:15px 0;border-bottom:1px solid #f3f2ed}.shortcut-item:last-child{border:0;padding-bottom:0}.shortcut-icon{width:37px;height:39px;display:grid;place-items:center;border-radius:11px;background:#f0edf7;color:#9b85b6;font-size:23px}.shortcut-item:nth-child(3) .shortcut-icon{background:#eaf3ed;color:#81a58b}.shortcut-item:nth-child(4) .shortcut-icon{background:#fbede4;color:#dba37f}.shortcut-item strong{display:block;font-size:12px;font-weight:600}.shortcut-item small{display:block;color:#aaa9a1;font-size:10px;margin-top:6px}.shortcut-item .arrow{margin-left:auto;color:#c4c2b8}.habit{padding:12px 10px;color:#99988e;display:flex;align-items:center;gap:11px;font-size:11px;line-height:1.9}.habit span:first-child{font-size:27px;color:#b1b6a2}footer{max-width:1120px;margin:29px auto 20px;padding:20px 0;border-top:1px solid #e9e8e1;color:#aaa99f;font-size:11px;display:flex;align-items:center;gap:8px}footer>span:last-of-type{margin-left:10px}footer button{margin-left:auto;background:transparent;color:#9c9b93;font-size:11px}.brand-dot{height:7px;width:7px;background:#d3b698;border-radius:50%}.page-title{margin:24px 0}.page-title .eyebrow{color:#bb8c65}.page-title h1{font-size:30px;margin:12px 0}.page-title p{color:#91928b;font-size:13px;line-height:1.8}.print-preview{background:#ecece5;border-radius:16px;padding:20px;min-height:360px;display:flex;justify-content:center;align-items:center;overflow:auto}.print-preview canvas{width:100%;max-width:380px;height:auto;box-shadow:0 5px 18px #32352b15;background:white}.preview-caption{text-align:center;font-size:11px;color:#98988c;margin:13px 0}.full-grid{display:grid;grid-template-columns:360px minmax(0,1fr);gap:24px}.full-grid .card{padding:25px}.form-stack>*+*{margin-top:20px}.table-wrap{overflow:auto;border-radius:12px;border:1px solid #e7e6dd}.memory-table{border-collapse:collapse;width:100%;font-variant-numeric:tabular-nums;text-align:center;min-width:650px}.memory-table td,.memory-table th{border:1px solid #fff9;padding:9px 3px;font-size:12px;font-weight:400}.memory-table th{background:#f1f0eb;font-weight:750}.memory-table td.q0{background:#e8efe7}.memory-table td.q1{background:#f8edcf}.memory-table td.q2{background:#e8e2f1}.memory-table td.q3{background:#f5e1d7}.memory-table td.bold{font-weight:850;color:#34333c}.memory-table td.selected{outline:2px solid #b87849;outline-offset:-2px}.legend{display:flex;gap:18px;flex-wrap:wrap;font-size:11px;color:#8e8d82;margin:17px 0}.legend i{width:10px;height:10px;border-radius:3px;display:inline-block;margin-right:5px}.table-tools{display:flex;align-items:center;justify-content:space-between;gap:16px;margin:18px 0}.table-tools p{font-size:12px;color:#96958b}.upload-area{border:2px dashed #dedacf;border-radius:20px;background:#faf9f5;padding:48px 20px;text-align:center;position:relative}.upload-icon{font-size:46px;color:#b9ac91;margin-bottom:15px}.upload-area h3{font-size:18px}.upload-area p{font-size:12px;color:#97958b;line-height:1.9}.upload-area input{position:absolute;inset:0;opacity:0;cursor:pointer;width:100%;height:100%}.photo-frame{position:relative;max-width:650px;margin:auto}.photo-frame img{width:100%;display:block;border-radius:12px}.photo-box{position:absolute;border:2px solid #d44d49;border-radius:4px;pointer-events:none}.photo-box.correct{border-color:#50a57f}.photo-box.unknown{border-color:#d1a23a}.photo-box span{background:#d44d49;color:#fff;font-size:10px;padding:1px 4px;position:absolute;top:-17px;left:-2px;white-space:nowrap}.photo-box.correct span{background:#50a57f}.photo-box.unknown span{background:#b39032}.status-banner{padding:12px 16px;border-radius:11px;background:#fff5e2;color:#a07e46;font-size:12px;line-height:1.8;margin-bottom:20px}.status-banner.ok{background:#edf5ee;color:#658d70}.how-steps{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin:27px 0}.how-steps b{font-size:11px;color:#b5a99b;background:#f1eee8;padding:6px 9px;border-radius:7px}.how-steps h4{font-size:13px;margin:16px 0 6px}.how-steps p{font-size:11px;color:#a09f94;line-height:1.8}.practice-shell{max-width:700px;margin:25px auto}.practice-top{display:flex;justify-content:space-between;align-items:center;font-size:13px;color:#96968d;margin-bottom:22px}.practice-top button{background:transparent;color:#93938b}.progress{height:6px;background:#eae7df;border-radius:10px;overflow:hidden}.progress>div{height:100%;background:#dba579;transition:width .2s}.question-card{text-align:center;padding:35px 20px 25px;margin-top:20px}.question-label{font-size:11px;letter-spacing:2px;color:#9b9a90}.equation{font-size:clamp(25px,6vw,43px);font-weight:650;font-variant-numeric:tabular-nums;margin:32px 0 23px;line-height:1.6;overflow-wrap:anywhere}.answer-input{font-size:30px;border:0;border-bottom:2px solid #dec7af;width:210px;text-align:center;padding:8px;background:transparent;color:#79604a;outline:none}.feedback{min-height:40px;font-size:13px;color:#879a7c;margin:16px 0 0}.feedback.wrong{color:#bc7c56}.keypad{display:grid;grid-template-columns:repeat(3,1fr);gap:9px;margin:19px auto;max-width:430px}.keypad button{font-size:24px;padding:17px;border-radius:13px;background:#fff;border:1px solid #e9e7de;box-shadow:0 2px 0 #e7e3d8;color:#5e5c54}.keypad button:active{transform:translateY(2px);box-shadow:none}.keypad button.symbol{font-size:18px;color:#a38b73;background:#f0ede6}.keypad .submit{background:#e98a59;color:white;grid-column:span 2;font-size:16px;border-color:#e98a59;box-shadow:0 2px 0 #ce784c}.result-circle{width:135px;height:135px;border:9px solid #e4ecdc;border-radius:50%;display:grid;align-content:center;margin:25px auto}.result-circle strong{font-size:37px;color:#78916e}.result-circle small{font-size:12px;color:#9c9f92}.stats{display:flex;justify-content:center;gap:35px;margin:25px 0;text-align:center}.stats b{display:block;font-size:22px}.stats span{display:block;font-size:11px;color:#aaa79d;margin-top:8px}.answer-list{display:grid;gap:10px;margin-top:22px}.answer-row{border-radius:10px;padding:13px;background:#f8f7f2;display:flex;justify-content:space-between;align-items:center;gap:15px;font-size:13px;line-height:1.7}.answer-row.correct{background:#eff5ed}.answer-row.wrong{background:#fcf0e8}.answer-row.unknown{background:#fbf5df}.answer-row small{color:#9a9689}.empty{text-align:center;padding:45px 15px;color:#a3a093;font-size:13px;line-height:2}.section-actions{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}dialog{border:1px solid #ece9df;border-radius:24px;padding:32px;max-width:620px;width:calc(100% - 32px);color:#47473e;background:#fffefa;box-shadow:0 30px 80px #0002}dialog::backdrop{background:#33352e60;backdrop-filter:blur(3px)}dialog h2{font-size:21px;margin-top:4px}dialog p{font-size:13px;color:#969185;line-height:1.9}.modal-close{position:absolute;top:10px;right:13px;background:transparent;font-size:27px;color:#aba698}#toast{position:fixed;bottom:100px;left:50%;transform:translateX(-50%);background:#45443beF;color:#fff;padding:13px 22px;border-radius:12px;font-size:13px;z-index:100;max-width:90vw;width:max-content;pointer-events:none;opacity:0;transition:opacity .2s}#toast.show{opacity:1}.loading{display:inline-block;width:14px;height:14px;border:2px solid #ddd;border-top-color:#c08052;border-radius:50%;animation:spin 1s linear infinite;margin-right:8px;vertical-align:middle}@keyframes spin{to{transform:rotate(360deg)}}.preview-mobile-note{display:none}.minor{font-size:11px;color:#a29f93;line-height:1.9}.error-text{color:#bd7455;font-size:12px;line-height:1.8}.top-label{color:#a39b8e;font-size:11px;letter-spacing:2px}.file-links{display:flex;gap:12px;flex-wrap:wrap}.file-links a{color:#a06c47;text-decoration:underline;font-size:12px}.recent-paper{font-size:12px;line-height:1.8;padding:14px;background:#f5f4ed;border-radius:10px;margin-top:15px}.toolbar{display:flex;gap:12px;align-items:center;margin:18px 0}.check-line{display:flex;align-items:center;gap:7px;font-size:12px;color:#939185}.offline{background:#fff5df;color:#a88647;padding:9px;text-align:center;font-size:12px}.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}
@media(min-width:1200px){#main{padding:0}.hero{min-height:228px}.card{padding:29px 31px}.content-grid{gap:26px;grid-template-columns:minmax(0,1fr) 300px}}
@media(max-width:950px){.header{padding:0 24px}.brand{font-size:20px}nav button{padding:11px;font-size:12px}.history-button span{display:none}.hero{padding:30px}.hero-art{margin:0;width:250px}.hero h1{font-size:29px}.content-grid{grid-template-columns:minmax(0,1fr) 240px}.side-card{padding:19px}.card{padding:23px}.full-grid{grid-template-columns:310px minmax(0,1fr)}footer{margin-left:24px;margin-right:24px}}
@media(max-width:700px){.header{height:78px;padding:0 21px}.brand{font-size:21px}.brandmark{width:38px;height:40px;font-size:22px}.brand small{font-size:9px}.history-button{font-size:23px}nav{position:fixed;bottom:0;left:0;right:0;z-index:20;background:#fffefaf5;backdrop-filter:blur(12px);padding:8px 6px calc(9px + env(safe-area-inset-bottom));border-top:1px solid #e9e6db;justify-content:space-around;gap:0}nav button{border-radius:12px;padding:5px 10px;font-size:10px;min-width:68px}nav button span{display:block;margin:0 0 4px;font-size:21px;line-height:1.1}nav button.active{background:transparent;color:#c8784a;box-shadow:none}#main{padding:0 17px;margin:7px auto 0;min-height:calc(100vh - 230px)}.hero{border-radius:21px;min-height:193px;padding:27px 24px}.eyebrow{font-size:9px}.hero h1{font-size:25px;line-height:1.65;margin:8px 0}.hero p{font-size:11px;max-width:210px}.hero-art{width:120px;height:150px;position:absolute;right:-14px;top:37px;opacity:.7;transform:scale(.72);transform-origin:right center}.math-sheet{left:0;width:123px;font-size:21px;padding:24px 12px}.math-sheet b{font-size:24px}.orbit-one{left:-23px;top:100px;width:42px;height:42px;font-size:22px}.orbit-two{right:-35px;top:-20px;width:42px;height:42px;font-size:25px}.orbit-three{right:-20px;bottom:-5px}.art-star{left:-16px;top:-12px;font-size:24px}.hero-copy{z-index:1}.content-grid{display:flex;flex-direction:column;gap:18px;margin-top:18px}.card{border-radius:19px;padding:23px 20px}.card-heading{margin-bottom:19px}.card-heading h2{font-size:17px}.step{font-size:9px}.tabs{margin-bottom:22px}.tabs button{font-size:12px;padding:11px 3px}.grade-grid{gap:6px}.chip{font-size:11px;padding:12px 2px}.term-row .chip{font-size:12px}.field-label{font-size:12px}.field-label .muted{font-size:10px}.choice-row{gap:7px}.choice-row .chip{min-width:54px;padding:10px 12px}.inline-number{width:62px;padding:10px 5px}.two-fields{gap:12px}.side-column{display:grid;grid-template-columns:1fr 1fr;gap:12px}.side-card{margin:0;border-radius:18px;padding:18px}.daily h3{font-size:19px;margin-top:19px}.daily p{font-size:11px}.side-title{font-size:12px}.sun{font-size:31px;right:11px}.shortcut-item{padding:10px 0;gap:8px}.shortcut-icon{width:29px;height:32px;font-size:18px;border-radius:8px}.shortcut-item strong{font-size:10px}.shortcut-item small{font-size:9px}.habit{grid-column:span 2;padding:0 6px}.side-link{font-size:11px}footer{margin:22px 20px 99px;padding-top:18px;font-size:10px;flex-wrap:wrap;gap:5px}footer>span:last-of-type{display:none}footer button{font-size:10px}.full-grid{display:flex;flex-direction:column;gap:18px}.full-grid .card{padding:22px 20px}.page-title{margin:17px 5px 23px}.page-title h1{font-size:25px}.page-title p{font-size:12px}.type-grid{grid-template-columns:repeat(2,1fr)}.type-option{padding:12px 10px;font-size:12px}.table-tools{align-items:flex-start;flex-direction:column}.table-tools .primary{width:100%}.memory-table{min-width:620px}.memory-table td,.memory-table th{font-size:11px;padding:8px 3px}.legend{gap:10px;font-size:10px}.how-steps{gap:12px}.how-steps h4{font-size:12px}.how-steps p{font-size:10px}.upload-area{padding:35px 15px}.practice-shell{margin-top:15px}.question-card{padding:29px 15px 18px}.equation{margin:27px 0 18px}.keypad{max-width:100%;gap:8px}.keypad button{padding:15px}.practice-top{font-size:11px}.stats{gap:27px}.answer-row{font-size:12px}.section-actions>*{flex:1}.preview-mobile-note{display:block;font-size:11px;color:#9e998a;text-align:center}.table-card{padding:18px 13px!important}.toolbar{flex-wrap:wrap}.toolbar .primary{width:100%}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
.math-sheet{white-space:nowrap;width:168px;font-size:19px;line-height:1.85;padding:23px 14px}.math-sheet b{font-size:23px}
@media(max-width:700px){.hero h1 em{display:block;width:max-content}.hero h1{font-size:24px;line-height:1.5}.hero-art{right:-22px;top:45px;opacity:.55}.hero p{max-width:225px;font-size:10px}.hero{min-height:218px}.math-sheet{width:150px;font-size:17px}.math-sheet b{font-size:21px}}
/* Compact mobile controls and a viewport-bound practice surface. */
.result-circle{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:4px}.result-circle strong,.result-circle small{display:block;width:100%}
@media(max-width:700px){
 .header{height:64px}.brand small{display:none}.brandmark{width:35px;height:35px}.hero{min-height:145px;padding:18px 21px}.hero h1{font-size:22px;margin:5px 0}.hero p,.hero .eyebrow{display:none}.hero-art{top:8px;transform:scale(.56)}
 .content-grid{margin-top:12px;gap:12px}.card{padding:17px 16px}.card-heading{margin-bottom:13px}.tabs{margin-bottom:15px}.tabs button{padding:9px 3px}.field-label{margin-bottom:7px}.field input,.field select{padding:9px 10px;font-size:16px}.grade-grid .chip{padding:9px 2px}.term-row{margin-top:8px}.term-row .chip{padding:8px 23px}.divider{margin:15px 0}.primary.wide{margin-top:16px}.notice,.start-foot,.side-column,.checks+.minor,.preview-caption{display:none}.topic-note{margin-top:12px;padding:8px 10px}.card .minor{margin:7px 0}.form-stack>*+*{margin-top:13px}.page-title{margin:10px 4px 16px}.page-title h1{font-size:24px;margin:5px 0}.page-title>.eyebrow,.page-title>p{display:none}footer{display:none}#main{padding-bottom:95px}.print-preview{min-height:220px;padding:12px}.full-grid .card{padding:18px 16px}.upload-area{padding:23px 12px}.upload-area p,.how-steps,.content-grid>aside:not(.side-column){display:none}.table-tools p{font-size:11px}
 body.solving{height:100dvh;overflow:hidden}body.solving .header,body.solving nav,body.solving footer{display:none}body.solving #main{height:100dvh;min-height:0;margin:0;padding:8px 12px calc(10px + env(safe-area-inset-bottom))}body.solving .practice-shell{height:100%;max-width:520px;margin:0 auto;display:flex;flex-direction:column;gap:9px}body.solving .practice-top{margin:0;min-height:31px;gap:8px;font-size:11px}body.solving .progress{flex:0 0 4px}body.solving .question-card{margin:0;padding:14px 12px 8px;flex:1 1 145px;min-height:130px;max-height:240px;display:flex;flex-direction:column;align-items:center;justify-content:center}body.solving .question-label{display:none}body.solving .equation{font-size:clamp(23px,7vw,35px);margin:0 0 8px;line-height:1.4}body.solving .answer-input{font-size:28px;padding:4px;width:170px}body.solving .feedback{min-height:24px;margin:8px 0 0;font-size:12px}body.solving .keypad{width:100%;margin:0;gap:7px;flex:1 1 230px;min-height:200px;max-height:320px;grid-auto-rows:minmax(30px,1fr)}body.solving .keypad button{padding:0;font-size:23px;border-radius:11px}body.solving .keypad .submit{font-size:15px}body.solving .section-actions{min-height:35px;gap:8px}body.solving .section-actions .secondary{padding:8px 10px;font-size:12px}body.solving #toast{bottom:55px}
 .result-circle{margin:18px auto}.stats{gap:18px}.stats b{font-size:20px}.practice-shell>.card>h2{font-size:20px}.top-label{display:none}
}
.advanced{margin-top:16px}.advanced summary{cursor:pointer;font-size:12px;color:#969184;padding:8px 0}.advanced[open] summary{margin-bottom:9px}
@media(max-width:700px){.type-grid{max-height:180px;overflow:auto}.advanced{margin-top:12px}.advanced summary{font-size:11px}.stats{align-items:center}.result-circle small{text-align:center}}

/* Keep all four multiplication choices on one row, including small phones. */
.big-choices{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:6px}.big-choices .chip{min-width:0;min-height:40px;padding:10px 3px;font-size:12px;white-space:nowrap}
@media(max-width:700px){.big-choices .chip{font-size:clamp(10px,2.7vw,12px)}}