:root{--bg-color: #0f172a;--surface-color: #1e293b;--primary-color: #10b981;--primary-hover: #059669;--accent-color: #f59e0b;--text-primary: #f8fafc;--text-secondary: #94a3b8;--error-color: #ef4444;--font-family: "Inter", system-ui, -apple-system, sans-serif;--radius-sm: .375rem;--radius-md: .5rem;--radius-lg: 1rem;--shadow-sm: 0 1px 2px 0 rgb(0 0 0 / .05);--shadow-lg: 0 10px 15px -3px rgb(0 0 0 / .1), 0 4px 6px -4px rgb(0 0 0 / .1)}*{box-sizing:border-box}body{margin:0;font-family:var(--font-family);background-color:var(--bg-color);color:var(--text-primary);line-height:1.5;-webkit-font-smoothing:antialiased}button{cursor:pointer;border:none;font-family:inherit}#root{width:100%;min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center}.container{width:100%;max-width:640px;padding:1.5rem;margin:0 auto}.btn-primary{background:linear-gradient(135deg,var(--primary-color),#0ea5e9);color:#fff;padding:.75rem 1.5rem;border-radius:var(--radius-lg);font-weight:600;transition:all .2s cubic-bezier(.4,0,.2,1);width:100%;font-size:1.125rem;box-shadow:0 4px 14px #10b98163}.btn-primary:hover{transform:translateY(-2px);box-shadow:0 6px 20px #10b98173;filter:brightness(1.1)}.btn-primary:active{transform:translateY(0)}.btn-secondary{background:#ffffff0d;color:var(--text-primary);padding:.75rem 1.5rem;border-radius:var(--radius-lg);font-weight:600;border:1px solid rgba(255,255,255,.1);transition:all .2s;width:100%;font-size:1.125rem}.btn-secondary:hover{background:#ffffff1a;border-color:#fff3}.btn-back{background:transparent;color:var(--text-secondary);padding:.5rem 1rem;border-radius:var(--radius-md);font-size:.875rem;display:flex;align-items:center;gap:.5rem;transition:all .2s;border:1px solid rgba(255,255,255,.1)}.btn-back:hover{color:var(--text-primary);background:#ffffff0d}.mahjong-tile{width:44px;height:60px;background-color:#fff;border-radius:4px;position:relative;box-shadow:1px 1px #ccc,2px 2px #ccc,3px 3px #aaa,3px 3px 5px #0000004d;cursor:pointer;-webkit-user-select:none;user-select:none;transition:transform .1s,box-shadow .1s;display:flex;justify-content:center;align-items:center;margin:0 2px;background:linear-gradient(135deg,#fdfbf7,#f0ebd8)}.mahjong-tile:active{transform:translate(2px,2px);box-shadow:1px 1px #aaa}.mahjong-tile:hover{filter:brightness(1.05);margin-top:-4px}.tile-image{width:100%;height:100%;object-fit:contain;display:block}.quiz-container{width:100%;display:flex;flex-direction:column;align-items:center;position:relative}.status-bar{width:100%;display:flex;justify-content:center;gap:3rem;margin-bottom:2rem;font-size:1.25rem;color:var(--text-secondary)}.tehai-row{display:flex;flex-wrap:wrap;justify-content:center;gap:0;background:#15803d;padding:20px;border-radius:8px;box-shadow:inset 0 0 20px #00000080;border:4px solid #b45309}.instruction{margin-bottom:1rem;font-weight:300;text-align:center}.feedback-overlay{position:absolute;inset:0;display:flex;justify-content:center;align-items:center;pointer-events:none;z-index:10;animation:fadeIn .1s ease-out}.mark{font-size:8rem;text-shadow:0 0 20px rgba(0,0,0,.5)}.circle{color:#10b981}.cross{color:#ef4444}@keyframes fadeIn{0%{opacity:0;transform:scale(.5)}to{opacity:1;transform:scale(1)}}