.app{max-width:1060px;margin:0 auto;padding:24px 16px 60px;min-height:100vh;display:flex;flex-direction:column;align-items:center}.app-header{text-align:center;margin-bottom:24px}.app-title{font-size:2rem;color:var(--color-primary);margin-bottom:4px}.app-subtitle{font-size:1rem;color:var(--color-text-light);font-weight:600}.sign-out-link{background:none;border:none;color:var(--color-text-light);font-family:var(--font-body);font-size:.8rem;font-weight:600;cursor:pointer;margin-top:4px;opacity:.7;transition:opacity .2s}.sign-out-link:hover{opacity:1}.app-mode-selector{margin-bottom:28px}.start-screen{display:flex;flex-direction:column;align-items:center;gap:24px;padding:40px 20px;text-align:center}.start-screen h2{font-size:1.8rem;color:var(--color-primary)}.start-screen p{font-size:1.1rem;color:var(--color-text-light);max-width:400px;line-height:1.6}.quiz-top-bar{display:flex;align-items:center;justify-content:space-between;width:100%;margin-bottom:20px;gap:16px}.quiz-progress{flex:1}.quiz-content{width:100%}.quiz-question{display:flex;flex-direction:column;align-items:center;gap:24px;padding:24px}.quiz-prompt{font-size:1.3rem;font-weight:700;color:var(--color-text);text-align:center;line-height:1.5;white-space:pre-line}.quiz-visual{display:flex;justify-content:center;align-items:center;width:100%}.quiz-answer-section{display:flex;flex-direction:column;align-items:center;gap:16px;width:100%}@media(max-width:768px){.app-title{font-size:1.6rem}.quiz-top-bar{flex-direction:column;align-items:stretch}}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--color-primary: #4361EE;--color-primary-light: #6B83F2;--color-correct: #06D6A0;--color-incorrect: #EF476F;--color-bg: #F8F9FE;--color-surface: #FFFFFF;--color-text: #2B2D42;--color-text-light: #8D99AE;--color-border: #E0E4F0;--fill-1: #60A5FA;--fill-2: #F472B6;--fill-3: #A78BFA;--fill-4: #34D399;--fill-5: #FBBF24;--fill-6: #FB923C;--fill-7: #F87171;--fill-8: #2DD4BF;--font-body: "Nunito", sans-serif;--font-heading: "Fredoka One", cursive;--radius-sm: 8px;--radius-md: 12px;--radius-lg: 20px;--radius-full: 9999px;--shadow-sm: 0 2px 8px rgba(43, 45, 66, .08);--shadow-md: 0 4px 16px rgba(43, 45, 66, .12);--shadow-lg: 0 8px 32px rgba(43, 45, 66, .16)}html{font-size:16px;-webkit-font-smoothing:antialiased}body{font-family:var(--font-body);background:var(--color-bg);color:var(--color-text);line-height:1.5;min-height:100vh}h1,h2,h3{font-family:var(--font-heading);line-height:1.2}button{font-family:var(--font-body);cursor:pointer;border:none;outline:none}input{font-family:var(--font-body);outline:none}.card{background:var(--color-surface);border-radius:var(--radius-lg);box-shadow:var(--shadow-md);padding:24px}.btn{display:inline-flex;align-items:center;justify-content:center;padding:12px 28px;border-radius:var(--radius-full);font-size:1.1rem;font-weight:700;transition:transform .15s,box-shadow .15s}.btn:hover{transform:translateY(-2px);box-shadow:var(--shadow-md)}.btn:active{transform:translateY(0)}.btn-primary{background:var(--color-primary);color:#fff}.btn-correct{background:var(--color-correct);color:#fff}.btn-ghost{background:transparent;color:var(--color-primary);border:2px solid var(--color-primary)}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}@keyframes popIn{0%{transform:scale(.8);opacity:0}70%{transform:scale(1.05)}to{transform:scale(1);opacity:1}}@keyframes shake{0%,to{transform:translate(0)}20%{transform:translate(-6px)}40%{transform:translate(6px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}.animate-fade-in{animation:fadeIn .4s ease-out}.animate-pop-in{animation:popIn .4s ease-out}.animate-shake{animation:shake .4s ease-out}