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.sidebar-reset{display:block}.board{border-width:0;border-radius:0;min-height:calc(100svh - 48px);padding:16px 10px 10px;box-shadow:inset 0 0 0 2px #fff9e82e}.algebra-row-tools{justify-content:flex-start}.algebra-row-tools button{flex:none}.scale-action{width:auto}.scale-action button{flex:none}.algebra-expression{align-items:center;gap:calc(6px * var(--equation-scale));min-height:calc(48px * var(--equation-scale))}.algebra-side{gap:calc(6px * var(--equation-scale));min-height:calc(44px * var(--equation-scale));padding:calc(2px * var(--equation-scale)) calc(4px * var(--equation-scale))}.algebra-equals{min-width:calc(30px * var(--equation-scale));min-height:calc(24px * var(--equation-scale));font-size:calc(1.8rem * var(--equation-scale))}.algebra-term{gap:calc(5px * var(--equation-scale));min-width:calc(38px * var(--equation-scale));min-height:calc(36px * var(--equation-scale));padding:calc(4px * var(--equation-scale)) calc(6px * var(--equation-scale));font-size:clamp(calc(1.2rem * var(--equation-scale)), calc(5vw * var(--equation-scale)), calc(1.65rem * var(--equation-scale)))}.board-footer{display:block}.answer-panel{padding:10px}.solve-main{grid-template-columns:minmax(0,1fr)}.solve-equation{gap:10px}.target-expression{margin-bottom:12px}.solve-equation .target-expression{margin-bottom:0}.answer-input{height:64px}.keypad button,.action-row button,.nav-row button{min-height:46px}.answer-pill{width:100%}.progress-panel{margin-top:12px}.board h2{font-size:clamp(2rem,10vw,2.6rem)}}.landing-page{min-height:100vh;color:var(--ink)}.landing-hero{grid-template-columns:minmax(280px,.72fr) minmax(0,1.28fr);align-items:center;gap:clamp(18px,4vw,46px);min-height:100svh;padding:clamp(16px,4vw,46px);display:grid}.landing-copy{align-self:center}.landing-kicker{color:var(--coral);letter-spacing:0;text-transform:uppercase;margin:0 0 12px;font-size:.9rem;font-weight:900}.landing-copy h1{max-width:9ch;color:var(--board);margin:0;font-family:Georgia,Times New 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