.qb-app {
    max-width: 480px;
    margin: 0 auto;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

.qb-login h2 { text-align: center; }
.qb-player-list {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    margin-bottom: 16px;
}
.qb-player-btn {
    padding: 14px 20px;
    font-size: 16px;
    border-radius: 10px;
    border: 2px solid #333;
    background: #fff;
    cursor: pointer;
}
.qb-pin-box { text-align: center; margin-top: 10px; }
.qb-pin-input {
    font-size: 18px;
    padding: 10px;
    width: 140px;
    text-align: center;
    margin-right: 8px;
}
.qb-error { color: #c0392b; font-weight: bold; }

.qb-btn, .qb-login-btn, .qb-buzzer-submit-btn {
    padding: 10px 18px;
    font-size: 16px;
    border-radius: 8px;
    border: none;
    background: #2d6cdf;
    color: #fff;
    cursor: pointer;
}

.qb-header {
    text-align: center;
    font-weight: bold;
    font-size: 18px;
    margin: 12px 0;
}

.qb-scoreboard {
    display: flex;
    justify-content: space-between;
    gap: 6px;
    margin-bottom: 16px;
}
.qb-score-item {
    flex: 1;
    background: #f2f2f2;
    border-radius: 8px;
    padding: 8px;
    text-align: center;
    font-size: 13px;
}
.qb-score-item.qb-me {
    background: #dbe9ff;
    border: 2px solid #2d6cdf;
}
.qb-score-item strong { display: block; font-size: 18px; }

.qb-question h3 { font-size: 20px; }

.qb-options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.qb-option-btn {
    padding: 16px;
    font-size: 17px;
    border-radius: 10px;
    border: 2px solid #2d6cdf;
    background: #fff;
    color: #2d6cdf;
    cursor: pointer;
}
.qb-option-btn:disabled { opacity: 0.5; }

.qb-buzz-btn {
    width: 100%;
    padding: 40px 0;
    font-size: 28px;
    font-weight: bold;
    border-radius: 16px;
    border: none;
    background: #e74c3c;
    color: #fff;
    cursor: pointer;
}

.qb-buzzer-answer-input {
    width: 100%;
    font-size: 16px;
    padding: 10px;
    margin: 10px 0;
    box-sizing: border-box;
}

.qb-waiting { text-align: center; color: #666; font-style: italic; margin-top: 30px; }

.qb-correct-answer { text-align: center; font-size: 18px; }

.qb-answer-list { margin-top: 10px; }
.qb-answer-row {
    display: flex;
    justify-content: space-between;
    padding: 8px;
    border-radius: 6px;
    margin-bottom: 6px;
}
.qb-answer-row.correct { background: #d4f7dc; }
.qb-answer-row.wrong { background: #fbdcdc; }

.qb-winner {
    text-align: center;
    margin-top: 40px;
    padding: 30px;
    background: #fff8dc;
    border-radius: 16px;
}
.qb-winner h2 { font-size: 28px; }

.qb-admin-wrap table code { font-size: 13px; }