.audio-btn {
    position: absolute;
    top: 0;
    right: 0;
    width: 70px;
    height: 70px;
    box-sizing: border-box;
    background: var(--ac-bg, rgba(0, 0, 0, 0.7));
    border: var(--ac-border-w, 8px) var(--ac-border-style, solid) var(--ac-color, #fff);
    border-radius: var(--ac-radius, 0);
    color: var(--ac-color, #fff);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    z-index: 5;
    box-shadow: var(--ac-glow, 0 0 15px rgba(0, 0, 0, 0.2));
    transition: background 0.2s ease, box-shadow 0.3s ease, filter 0.2s ease;
    user-select: none;
    -webkit-user-select: none;
    pointer-events: auto;
    font-family: var(--ac-font, inherit);
}
.audio-btn:hover {
    filter: brightness(1.15);
}
.audio-btn:active {
    filter: brightness(0.95);
}
.audio-btn svg {
    width: 26px;
    height: 26px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    pointer-events: none;
}
.audio-popup-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.55);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 10050;
    display: none;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.25s ease;
}
.audio-popup-backdrop.open {
    display: flex;
    opacity: 1;
}
.audio-popup {
    position: relative;
    background: var(--ac-bg, rgba(0, 0, 0, 0.85));
    border: var(--ac-border-w, 8px) var(--ac-border-style, solid) var(--ac-color, #fff);
    border-radius: calc(var(--ac-radius, 0) * 0.4);
    color: var(--ac-color, #fff);
    font-family: var(--ac-font, system-ui, -apple-system, Segoe UI, Roboto, sans-serif);
    width: 380px;
    max-width: calc(100vw - 40px);
    padding: 0;
    box-shadow:
        var(--ac-glow, 0 0 15px rgba(0, 0, 0, 0.2)),
        0 24px 60px rgba(0, 0, 0, 0.45);
    transform: translateY(20px) scale(0.96);
    opacity: 0;
    transition: transform 0.28s cubic-bezier(0.34, 1.56, 0.64, 1), opacity 0.25s ease;
}
.audio-popup-backdrop.open .audio-popup {
    transform: translateY(0) scale(1);
    opacity: 1;
}
.audio-popup-titlebar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 12px;
    border-bottom: 2px solid currentColor;
    font-size: 11px;
    letter-spacing: 3px;
    text-transform: uppercase;
    opacity: 0.9;
}
.audio-popup-titlebar .ac-tb-label {
    font-weight: 700;
}
.audio-popup-titlebar .ac-tb-dots {
    display: inline-flex;
    gap: 6px;
    align-items: center;
}
.audio-popup-titlebar .ac-tb-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: currentColor;
    opacity: 0.35;
    display: inline-block;
}
.audio-popup-titlebar .ac-tb-close {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: #ff5f57;
    border: none;
    padding: 0;
    cursor: pointer;
    opacity: 1;
    position: relative;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
    box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.25) inset;
}
.audio-popup-titlebar .ac-tb-close:hover {
    transform: scale(1.15);
    box-shadow: 0 0 8px #ff5f57, 0 0 0 1px rgba(0, 0, 0, 0.25) inset;
}
.audio-popup-titlebar .ac-tb-close::before {
    content: '×';
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(0, 0, 0, 0.55);
    font-size: 14px;
    font-weight: 900;
    line-height: 1;
    opacity: 0;
    transition: opacity 0.15s ease;
    font-family: system-ui, sans-serif;
}
.audio-popup-titlebar .ac-tb-close:hover::before {
    opacity: 1;
}
.audio-popup-body {
    padding: 18px 26px 24px;
}
.audio-popup-header {
    text-align: center;
    margin-bottom: 22px;
}
.audio-popup-symbols {
    font-size: 16px;
    letter-spacing: 10px;
    opacity: 0.5;
    margin-bottom: 8px;
    line-height: 1;
    font-family: 'Courier New', monospace;
}
.audio-popup-symbols::before {
    content: var(--ac-symbols, '· · · ·');
}
.audio-popup-title {
    font-size: 1.6em;
    font-weight: 800;
    letter-spacing: 3px;
    text-transform: uppercase;
    margin: 0 0 4px;
    line-height: 1;
    color: var(--ac-color, #fff);
}
.audio-popup-subtitle {
    font-size: 11px;
    letter-spacing: 2px;
    opacity: 0.65;
    text-transform: uppercase;
}
.audio-slider-group {
    display: flex;
    flex-direction: column;
    gap: 18px;
}
.audio-slider {
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.audio-slider-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    letter-spacing: 2px;
    text-transform: uppercase;
    font-weight: 700;
}
.audio-slider-value {
    font-variant-numeric: tabular-nums;
    font-weight: 800;
    opacity: 0.85;
    min-width: 3ch;
    text-align: right;
}
.audio-slider-input {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    background: currentColor;
    background: color-mix(in srgb, var(--ac-color, #fff) 25%, transparent);
    outline: none;
    cursor: pointer;
    border-radius: 999px;
    padding: 0;
    margin: 0;
}
.audio-slider-input::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--ac-color, #fff);
    border: 2px solid var(--ac-bg, #000);
    cursor: pointer;
    box-shadow: 0 0 8px color-mix(in srgb, var(--ac-color, #fff) 60%, transparent);
    transition: transform 0.15s ease;
}
.audio-slider-input::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}
.audio-slider-input::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--ac-color, #fff);
    border: 2px solid var(--ac-bg, #000);
    cursor: pointer;
    box-shadow: 0 0 8px color-mix(in srgb, var(--ac-color, #fff) 60%, transparent);
}
.audio-slider-icon {
    display: inline-block;
    width: 16px;
    text-align: center;
    margin-right: 8px;
    opacity: 0.8;
}
.audio-popup-footer {
    margin-top: 20px;
    padding-top: 14px;
    border-top: 1px solid color-mix(in srgb, var(--ac-color, #fff) 25%, transparent);
    display: flex;
    justify-content: center;
}
.audio-popup-reset {
    background: transparent;
    border: 1px solid currentColor;
    color: inherit;
    font-family: inherit;
    font-size: 10px;
    letter-spacing: 3px;
    text-transform: uppercase;
    padding: 8px 18px;
    cursor: pointer;
    transition: background 0.15s ease;
    border-radius: calc(var(--ac-radius, 0) * 0.3);
}
.audio-popup-reset:hover {
    background: color-mix(in srgb, var(--ac-color, #fff) 15%, transparent);
}
@media (max-width: 480px) {
    .audio-btn { width: 56px; height: 56px; }
    .audio-btn svg { width: 22px; height: 22px; }
    .audio-popup { width: calc(100vw - 32px); }
    .audio-popup-body { padding: 14px 18px 18px; }
    .audio-popup-title { font-size: 1.3em; }
}