body { background: #e0f7fa; font-family: 'Zen Maru Gothic', sans-serif; display: flex; flex-direction: column; align-items: center; margin: 0; padding: 20px; color: #333; }
.container { background: white; padding: 20px; border-radius: 16px; box-shadow: 0 4px 15px rgba(0,0,0,0.05); width: 100%; max-width: 420px; text-align: center; }
h1 { font-size: 1.2rem; color: #0277bd; }
.level-badge { display: inline-block; background: #ffb74d; color: white; padding: 4px 12px; border-radius: 12px; font-size: 0.8rem; font-weight: bold; margin-bottom: 10px; }
#question-text { font-size: 1rem; font-weight: bold; margin-bottom: 20px; text-align: left; }
.options-grid { display: flex; flex-direction: column; gap: 10px; }
.back-btn {position: absolute;top: 10px;left: 15px;padding: 8px 15px;background-color: rgba(255,255,255,0.9);text-decoration: none;color: #333;font-weight: bold;border-radius: 20px;box-shadow: 0 2px 5px rgba(0,0,0,0.2);z-index: 20;font-size: 0.9rem;}
.option-btn { padding: 12px; background: #f5f5f5; border: 2px solid #b0bec5; border-radius: 10px; font-weight: bold; cursor: pointer; text-align: left; }
.option-btn.correct { background: #c8e6c9; border-color: #388e3c; }
.option-btn.incorrect { background: #ffcdd2; border-color: #d32f2f; }
.hidden { display: none !important; }