:root{--ink:#16324a;--muted:#718195;--blue:#4778ef;--blue2:#6b8ff6}*{box-sizing:border-box}html{background:#e8eef7}body{margin:0;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",Arial,sans-serif}button,input{font:inherit;-webkit-tap-highlight-color:transparent}.app{width:100%;max-width:480px;min-height:100dvh;margin:auto;overflow:hidden;background:#f7f9fd}.setup-screen{background:linear-gradient(180deg,#edf5ff 0 35%,#f8fafc 35%)}
.hero{position:relative;min-height:330px;padding:24px 24px 32px;overflow:hidden}.hero:before,.hero:after{content:"";position:absolute;border-radius:50%;background:#fff8}.hero:before{width:180px;height:180px;right:-75px;top:-55px}.hero:after{width:70px;height:70px;left:-28px;bottom:20px}.brand{display:flex;align-items:center;gap:9px;font-size:17px;font-weight:800}.brand-mark{display:grid;place-items:center;width:30px;height:30px;border-radius:10px;background:var(--blue);color:#fff;box-shadow:0 6px 16px #4778ef40}.eyebrow{margin:42px 0 8px;color:var(--blue);font-size:13px;font-weight:800;letter-spacing:2px}.hero h1{margin:0;font-size:38px;line-height:1.18;letter-spacing:-1.5px}.hero h1 em{color:var(--blue);font-style:normal}.hero>p:last-child{margin:16px 0;color:var(--muted);font-size:14px}.mascot{position:absolute;right:18px;top:78px;width:145px;height:150px;border-radius:45% 55% 48% 52%;background:linear-gradient(145deg,#cce4ff,#e9f3ff);transform:rotate(5deg)}.mascot b{position:absolute;font-size:61px;left:43px;top:43px;filter:drop-shadow(0 8px 8px #4778ef25);transform:rotate(-5deg)}.mascot span{position:absolute;font-size:17px;font-weight:bold;color:var(--blue)}.mascot span:nth-child(1){left:12px;top:28px}.mascot span:nth-child(2){right:16px;top:18px}.mascot span:nth-child(3){left:20px;bottom:20px}.mascot span:nth-child(4){right:15px;bottom:27px}
.panel{position:relative;margin-top:-18px;padding:25px 20px 28px;border-radius:28px 28px 0 0;background:#fff;box-shadow:0 -8px 35px #3661900c}.section-title{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px}.section-title>div{display:flex;align-items:center;gap:9px}.section-title span{display:grid;place-items:center;width:24px;height:24px;border-radius:8px;background:#e7efff;color:var(--blue);font-weight:900;font-size:13px}.section-title h2{font-size:17px;margin:0}.section-title>small{color:#9aa6b5;font-size:11px}.grade-tabs{display:grid;grid-template-columns:repeat(3,1fr);gap:6px;margin-bottom:14px;padding:5px;border-radius:16px;background:#f1f4f8}.grade-tabs button{height:42px;border:0;border-radius:12px;background:transparent;color:#8391a1;font-size:13px;font-weight:700}.grade-tabs button.active{background:#fff;color:var(--blue);box-shadow:0 4px 12px #36547616}.grade-tabs strong{font-size:17px}.levels{display:grid;gap:9px}.level{display:flex;align-items:center;width:100%;padding:12px 13px;border:1.5px solid #e8edf4;border-radius:16px;background:#fff;text-align:left;color:var(--ink);transition:.15s}.level:active{transform:scale(.985)}.level.active{border-color:var(--blue);background:#f3f7ff;box-shadow:0 7px 18px #4778ef12}.level i{display:grid;place-items:center;width:39px;height:39px;border-radius:12px;background:#f2f5f8;font-style:normal;font-size:20px}.level.active i{background:#e3edff}.level>span{display:flex;flex-direction:column;gap:3px;flex:1;margin-left:12px}.level strong{font-size:14px}.level small{font-size:11px;color:#929eac}.level b{display:grid;place-items:center;width:22px;height:22px;border-radius:50%;color:#bcc6d2}.level.active b{background:var(--blue);color:#fff;font-size:12px}.count-title{margin-top:24px}.count-picker{display:grid;grid-template-columns:52px 1fr 52px;gap:9px}.count-picker>button{border:1.5px solid #e0e7f0;border-radius:14px;background:#f8fafc;color:var(--blue);font-size:24px;font-weight:700}.count-picker label{display:flex;align-items:center;justify-content:center;height:55px;border:1.5px solid var(--blue);border-radius:14px;background:#f3f7ff}.count-picker input{width:70px;border:0;outline:0;background:transparent;color:var(--ink);text-align:center;font-size:25px;font-weight:850;-moz-appearance:textfield}.count-picker input::-webkit-inner-spin-button{display:none}.count-picker small{color:#718195;font-size:12px}.count-presets{display:flex;justify-content:center;gap:8px;margin-top:10px}.count-presets button{border:0;border-radius:20px;background:#f1f4f8;color:#748396;padding:6px 13px;font-size:11px;font-weight:700}.summary{display:flex;align-items:center;gap:12px;margin-top:20px;padding:13px 14px;border-radius:15px;background:#f6f8fb}.summary>span{font-size:25px}.summary p{margin:0;font-size:12px;color:#718195}.summary strong{color:var(--ink)}.summary small{display:block;margin-top:3px;color:#9aa6b5}.primary{width:100%;border:0;border-radius:17px;background:linear-gradient(135deg,var(--blue),var(--blue2));box-shadow:0 12px 25px #4778ef45;color:#fff;font-weight:800;font-size:17px;padding:17px;cursor:pointer}.primary span{float:right;font-size:22px;line-height:18px}.primary:active{transform:translateY(1px)}.start{margin-top:15px}footer{text-align:center;padding:5px 0 22px;color:#a7b0bc;font-size:11px;letter-spacing:1px;background:#fff}
.quiz-screen{display:flex;flex-direction:column;padding:20px;background:linear-gradient(180deg,#edf5ff,#f8fafc 44%)}.quiz-header{display:flex;align-items:center;gap:13px}.icon-button{width:38px;height:38px;border:0;border-radius:12px;background:#fff;color:#8290a1;font-size:25px;box-shadow:0 4px 14px #36547612}.progress-wrap{flex:1}.progress-label{display:flex;justify-content:space-between;margin-bottom:7px;color:#758497;font-size:11px;font-weight:700}.progress{height:7px;border-radius:9px;background:#dce5f0;overflow:hidden}.progress i{display:block;height:100%;border-radius:9px;background:linear-gradient(90deg,var(--blue),#7aa0ff);transition:width .35s}.timer{display:flex;gap:5px;align-items:center;font-size:13px;font-weight:800;font-variant-numeric:tabular-nums}.question-card{margin:34px 0 16px;padding:26px 12px 21px;border-radius:27px;background:#fff;text-align:center;box-shadow:0 16px 40px #36547612}.mini-tag{display:inline-block;padding:7px 12px;border-radius:30px;background:#f2f6fc;color:#718195;font-size:11px;font-weight:700}.equation{display:flex;align-items:center;justify-content:center;gap:14px;margin:29px 0 20px;font-size:clamp(32px,10vw,46px);font-weight:850;font-variant-numeric:tabular-nums}.operator{color:var(--blue)}.equals{color:#aeb9c6}.answer{display:grid;place-items:center;min-width:66px;height:68px;padding:0 10px;border:2px dashed #b9c8dc;border-radius:16px;color:#a9b6c5}.answer.filled{border-style:solid;border-color:var(--blue);background:#eff4ff;color:var(--blue)}.feedback{min-height:22px;color:#8b98a8;font-size:13px;font-weight:700}.question-card.right .answer{border-color:#42bf91;background:#e9faf4;color:#16996b}.question-card.right .feedback{color:#16996b}.question-card.wrong .answer{border-color:#ff8c78;background:#fff1ed;color:#e45e48}.question-card.wrong .feedback{color:#e45e48}.quiz-actions{display:grid;grid-template-columns:1fr 1.15fr;gap:10px;margin-top:auto;margin-bottom:14px}.quiz-actions button{height:52px;border-radius:15px;font-size:14px;font-weight:800}.keyboard-toggle{border:1.5px solid #d7e3f4;background:#fff;color:var(--blue)}.next{border:0;background:var(--blue);color:#fff;box-shadow:0 8px 18px #4778ef30}.keypad{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;padding-bottom:max(10px,env(safe-area-inset-bottom))}.key{height:58px;border:1px solid #e7edf4;border-radius:17px;background:#fff;box-shadow:0 5px 12px #3654760d;color:var(--ink);font-size:22px;font-weight:750}.key:active{background:#edf3ff;transform:scale(.97)}.key.ok{border:0;background:var(--blue);color:#fff;font-size:15px}.key.ok:disabled{background:#bcc9dc}
.result-screen{display:grid;place-items:center;padding:24px;background:radial-gradient(circle at 50% 18%,#dceaff,transparent 34%),#f7f9fd}.result-card{width:100%;padding:34px 20px;border-radius:30px;background:#fff;text-align:center;box-shadow:0 20px 55px #36547616}.celebrate{font-size:68px}.result-card .eyebrow{margin:17px 0 6px}.result-card h1{margin:0;font-size:31px}.result-note{color:#8997a7;font-size:13px}.score-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin:28px 0}.score-grid>div{display:flex;flex-direction:column;gap:5px;padding:15px 4px;border-radius:15px;background:#f6f8fb}.score-grid span{font-size:20px}.score-grid strong{font-size:17px}.score-grid em{font-size:11px;font-style:normal;color:#8b98a8}.score-grid small{font-size:10px;color:#96a2b0}.secondary{width:100%;margin-top:10px;padding:14px;border:0;background:transparent;color:#728196;font-weight:700}
@media(max-width:370px){.hero{padding-left:18px}.hero h1{font-size:33px}.mascot{right:-4px;transform:scale(.86) rotate(5deg)}.panel{padding-left:15px;padding-right:15px}.equation{gap:8px}.answer{min-width:57px;height:60px}}