/* ==========================================================================
   AUDIO NARRATION CSS - BỘ ĐIỀU KHIỂN ÂM THANH THUYẾT MINH MP3
   Khoa Nghiệp vụ cơ bản - Học viện PCCC và CNCH
   ========================================================================== */

/* Nút bấm Bật/Tắt thuyết minh MP3 */
.btn-audio-pill {
    background: linear-gradient(135deg, #16a34a 0%, #15803d 100%);
    color: #ffffff;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12.5px;
    font-weight: 700;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 7px;
    transition: all 0.2s;
    box-shadow: 0 2px 8px rgba(22, 163, 74, 0.3);
    user-select: none;
}

.btn-audio-pill:hover {
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.4);
    transform: translateY(-1px);
}

.btn-audio-pill.muted {
    background: #334155;
    color: #94a3b8;
    box-shadow: none;
}

.btn-audio-pill.muted:hover {
    background: #475569;
    color: #e2e8f0;
}

/* Sóng âm mini nhấp nháy khi đang phát audio */
.audio-mini-bars {
    display: inline-flex;
    align-items: flex-end;
    gap: 2px;
    height: 12px;
}

.audio-mini-bars span {
    width: 2.5px;
    height: 3px;
    background: #ffffff;
    border-radius: 1px;
    transition: height 0.15s ease;
}

.btn-audio-pill.playing .audio-mini-bars span:nth-child(1) {
    animation: waveBar 0.7s infinite alternate ease-in-out;
}

.btn-audio-pill.playing .audio-mini-bars span:nth-child(2) {
    animation: waveBar 0.5s infinite alternate ease-in-out 0.2s;
}

.btn-audio-pill.playing .audio-mini-bars span:nth-child(3) {
    animation: waveBar 0.8s infinite alternate ease-in-out 0.4s;
}

@keyframes waveBar {
    0% { height: 3px; }
    100% { height: 12px; }
}

.btn-audio-pill.muted .audio-mini-bars {
    display: none;
}