.home-wrapper{min-height:100vh;display:flex;flex-direction:column;align-items:center;padding:40px 20px;background:linear-gradient(180deg,#0a0a20,#1a1a40);color:#fff;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif}.home-title{font-size:48px;font-weight:700;margin-bottom:40px;text-shadow:0 0 20px rgba(74,144,217,.5)}.grade-section{margin-bottom:50px;text-align:center}.grade-label{font-size:18px;color:#aaa;margin-bottom:16px}.grade-buttons{display:flex;gap:12px;flex-wrap:wrap;justify-content:center}.grade-button{padding:12px 24px;font-size:18px;font-weight:700;border:2px solid #4a90d9;border-radius:8px;background:#1a3a5a;color:#fff;cursor:pointer;transition:all .2s ease}.grade-button:hover{background:#2a5a8a;border-color:#6bb5ff}.grade-button.selected{background:#4a90d9;border-color:#6bb5ff;box-shadow:0 0 15px #4a90d980}.games-section{width:100%;max-width:800px;text-align:center}.games-label{font-size:18px;color:#aaa;margin-bottom:24px}.games-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:24px;padding:0 20px}.game-card{background:linear-gradient(135deg,#1a2a4a,#0a1a2a);border:2px solid #3a5a7a;border-radius:16px;padding:0;cursor:pointer;transition:all .3s ease;text-align:center;overflow:hidden}.game-card:hover{transform:translateY(-4px);border-color:#4a90d9;box-shadow:0 8px 30px #4a90d94d}.game-preview{height:140px;background:linear-gradient(135deg,#2a3a5a,#1a2a4a);display:flex;align-items:center;justify-content:center;border-bottom:1px solid #3a5a7a}.game-icon{font-size:64px}.game-title{font-size:24px;font-weight:700;margin:16px 20px 8px;color:#fff}.game-description{font-size:14px;color:#aaa;margin:0 20px 20px;line-height:1.4}@media(max-width:480px){.home-title{font-size:36px}.grade-button{padding:10px 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svg{width:24px;height:24px}.game-header__level{font-size:18px;font-weight:700;color:#fff;text-align:center;flex:1}.game-header__logo{width:44px;height:44px}.flashcard-container{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:20px;background:linear-gradient(180deg,#0a0a20,#1a2a4a);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;gap:20px}.health-container{display:flex;gap:12px;margin-bottom:10px}.health-icon{width:48px;height:48px;filter:drop-shadow(0 0 8px rgba(74,144,217,.8));transition:transform .3s ease}.health-icon.lost{filter:drop-shadow(0 0 6px rgba(255,68,68,.6));animation:health-lost .5s ease-out}@keyframes health-lost{0%{transform:translateY(0) scale(1);opacity:1}50%{transform:translateY(20px) scale(.8);opacity:.5}to{transform:translateY(0) scale(1);opacity:.2}}.timer-container{width:100%;max-width:400px;text-align:center}.timer{font-size:48px;font-weight:700;color:#fff;margin-bottom:10px;text-shadow:0 0 10px rgba(74,144,217,.5)}.progress{height:8px;background:#4a90d9;border-radius:4px;transition:width .1s linear,background .3s ease}.progress-count{font-size:18px;color:#8ab4f8;margin-bottom:10px}.flashcard{width:100%;max-width:400px;min-height:200px;background:linear-gradient(135deg,#1a3a5a,#0a2a4a);border:3px solid #4a90d9;border-radius:20px;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:30px;box-shadow:0 8px 30px #0000004d;transition:transform .1s ease,border-color .2s ease,background .2s ease}.flashcard.correct{border-color:#4ad94a;background:linear-gradient(135deg,#1a4a3a,#0a3a2a)}.flashcard.wrong{border-color:#d94a4a;background:linear-gradient(135deg,#4a1a1a,#3a0a0a)}.flashcard.timeout{border-color:#d9a44a;background:linear-gradient(135deg,#4a3a1a,#3a2a0a);animation:timeout-pulse 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rgba(74,144,217,.8)}@media(max-width:480px){.timer{font-size:36px}.problem{font-size:28px}.answer{font-size:36px}.flashcard{min-height:160px;padding:20px}.health-icon{width:36px;height:36px}.game-over-content h1{font-size:36px}.game-over-content .stats{font-size:18px}}*{margin:0;padding:0;box-sizing:border-box}html,body{width:100%;height:100%;background-color:#0a0a20}#app{width:100%;min-height:100%}button,.keypad-button{-webkit-user-select:none;user-select:none}body.with-game-header{--header-height: calc(48px + env(safe-area-inset-top, 0px)) }body.with-game-header #app{min-height:calc(100vh - var(--header-height));margin-top:var(--header-height)}