body { font-family: 'Segoe UI', sans-serif; background: #fff; margin: 0; display: flex; justify-content: center; }
.app-container { width: 100%; max-width: 450px; padding: 20px; position: relative; min-height: 90vh; }
.header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 30px; }
h3 { margin: 0; font-size: 1.2rem; }
h3 span { color: #888; }
.progress-info { text-align: right; width: 40%; }
.progress-bar-bg { background: #eee; height: 8px; border-radius: 10px; margin-bottom: 5px; overflow: hidden; }
#progress-fill { background: #3b82f6; width: 10%; height: 100%; transition: 0.3s; }
#question-text { font-size: 1.3rem; margin-bottom: 25px; line-height: 1.4; }
.option { border: 2px solid #eee; border-radius: 12px; padding: 15px; margin-bottom: 12px; cursor: pointer; transition: 0.2s; font-size: 1rem; }
.option:hover { border-color: #3b82f6; background: #f0f7ff; }
.correct-opt { border-color: #10b981 !important; background: #ecfdf5; }
.wrong-opt { border-color: #ef4444 !important; background: #fef2f2; }
#feedback-box { position: fixed; bottom: 0; left: 0; right: 0; background: #d1fae5; padding: 20px; border-radius: 20px 20px 0 0; box-shadow: 0 -5px 15px rgba(0,0,0,0.05); }
.hidden { display: none; }
#next-btn { background: #10b981; color: white; border: none; padding: 12px; width: 100%; border-radius: 10px; font-size: 1.1rem; cursor: pointer; margin-top: 10px; }