.steps{background:var(--cream);gap:6px;padding:8px 16px;display:flex;overflow-x:auto}.steps span{background:var(--white);border:2px solid var(--line);color:var(--sub);border-radius:999px;flex:none;padding:4px 12px;font-size:14px}.steps span.now{border-color:var(--mint);background:var(--mint);color:#fff;font-weight:700}.steps span.done{color:var(--mint);border-color:var(--mint-l)}.stage{flex:1;grid-template-columns:3fr 2fr;gap:14px;width:100%;max-width:1200px;margin:0 auto;padding:6px 16px 16px;display:grid}.stage.wide{grid-template-columns:1fr}@media (width<=820px){.stage{grid-template-columns:1fr}}.board,.side{background:var(--white);border:2px solid var(--line);border-radius:var(--radius);min-width:0;padding:14px}.side:empty{display:none}.board{text-align:center;flex-direction:column;justify-content:center;align-items:center;gap:12px;display:flex}.board .scene{font-size:19px}.board svg.tray{width:100%;height:auto}.board svg.cup{width:100%;max-width:360px;height:auto}.cup-label{color:var(--sub);margin-bottom:-8px;font-size:15px}.side{flex-direction:column;justify-content:center;gap:12px;display:flex}.side h2{text-align:center;margin:0;font-size:19px}.choices{gap:10px;display:grid}.choice{background:var(--white);border:3px solid var(--line);min-height:64px;color:var(--ink);border-radius:14px;padding:10px;font-size:24px;font-weight:700}.choice:hover{border-color:var(--mint)}.choice.ok{border-color:var(--mint);background:var(--mint-l)}.choice.ng{border-color:var(--berry);background:#fff1f3;animation:.3s shake}.choice.small{font-size:18px}@keyframes shake{25%{transform:translate(-6px)}75%{transform:translate(6px)}}.note{background:var(--cream);text-align:left;border-radius:12px;padding:10px 12px;font-size:17px}.rule-card{background:var(--mint-l);border:3px solid var(--mint);text-align:center;border-radius:18px;padding:16px 18px;font-size:22px;font-weight:700}.eq-steps{flex-direction:column;align-items:center;gap:10px;display:flex}.eq-steps .eq{font-size:26px}.pop{animation:.4s ease-out pop}@keyframes pop{0%{opacity:0;transform:scale(.9)}to{opacity:1;transform:scale(1)}}.answer{vertical-align:middle;align-items:center;gap:6px;display:inline-flex}.answer .stack{flex-direction:column;align-items:center;gap:4px;display:inline-flex}.answer .bar{border-top:4px solid var(--ink);width:78px}.box{border:3px solid var(--line);background:var(--white);width:78px;height:56px;color:var(--ink);border-radius:10px;justify-content:center;align-items:center;padding:0;font-size:32px;font-weight:700;display:inline-flex}.box.active{border-color:var(--berry);box-shadow:0 0 0 4px var(--berry-ll)}.box.whole{width:64px;height:64px}.box.whole[hidden]{display:none}.problem{font-size:34px}.pad{grid-template-columns:repeat(3,1fr);gap:8px;display:grid}.pad button{border:2px solid var(--mint);background:var(--white);min-height:58px;color:var(--ink);border-radius:12px;font-size:26px;font-weight:700}.pad button.fn{color:var(--mint);font-size:16px}.pad .wide3{grid-column:span 3}.pad .submit{background:var(--mint);color:#fff;font-size:20px;box-shadow:0 3px #146a62}.feedback{text-align:left;border-radius:14px;max-width:480px;padding:10px 14px;font-size:18px}.feedback.mistake{border:2px solid var(--berry);background:#fff1f3}.feedback.good{background:var(--mint-l);border:2px solid var(--mint)}.feedback.hint{background:var(--cream);border:2px solid var(--choco-l)}.feedback .row{flex-wrap:wrap;gap:8px;margin-top:8px;display:flex}.feedback .btn{min-height:46px;padding:6px 12px;font-size:16px}.meter{justify-content:center;gap:6px;display:flex}.meter i{background:var(--line);border-radius:50%;width:16px;height:16px;display:inline-block}.meter i.ok{background:var(--mint)}.meter i.now{outline:3px solid var(--berry)}.level{color:var(--sub);font-size:14px}.divisors{flex-wrap:wrap;justify-content:center;gap:8px;display:flex}.divisors[hidden]{display:none}.stars-big{color:var(--caramel);letter-spacing:6px;font-size:56px}dialog{background:var(--cream);border:none;border-radius:20px;width:100%;max-width:min(900px,94vw);padding:18px}dialog::backdrop{background:#3a2a2080}.check-steps{grid-template-columns:repeat(3,1fr);gap:10px;display:grid}@media (width<=720px){.check-steps{grid-template-columns:1fr}}.check-steps>div{background:var(--white);text-align:center;border-radius:14px;flex-direction:column;align-items:center;gap:6px;padding:10px;display:flex}.check-steps svg.tray{width:100%;height:auto}.check-steps .eq{font-size:22px}.arrow-note{color:var(--mint);font-weight:700}.dialog-actions{justify-content:flex-end;margin-top:12px;display:flex}.scene.word{text-align:left;background:var(--cream);border-radius:14px;max-width:640px;padding:10px 14px;font-size:20px;line-height:1.8}.picture{justify-content:center;width:100%;display:flex}.picture svg.tray{width:100%;height:auto}.pick-q{margin:0 0 8px;font-size:19px}#pick{width:100%;max-width:480px}.eq[hidden]{display:none}.legend{color:var(--sub);font-size:15px}.legend i{vertical-align:-2px;border-radius:3px;width:14px;height:14px;margin:0 2px;display:inline-block}.plates{flex-wrap:wrap;justify-content:center;gap:10px;width:100%;display:flex}.plates>div{flex:140px;max-width:220px}.plates svg.tray{width:100%;height:auto}.cards{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;width:100%;display:grid}.cards .note{height:100%}