* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    overflow: hidden;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #fff;
}

#karaoke-bg {
    position: fixed;
    inset: 0;
    background: url('../img/karaoke/karaoke_background.png') center/cover no-repeat;
    z-index: 0;
}

#karaoke-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 1;
}

#btn-back {
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 10;
    color: #f1c40f;
    text-decoration: none;
    font-size: 1.1rem;
    padding: 8px 18px;
    border: 1px solid rgba(241, 196, 15, 0.4);
    border-radius: 8px;
    background: rgba(0, 0, 0, 0.4);
    transition: background 0.2s;
}

#btn-back:hover {
    background: rgba(241, 196, 15, 0.15);
}

/* --- Lyrics --- */

#lyrics-container {
    position: fixed;
    top: 80px;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    width: 90%;
    max-width: 800px;
    overflow-y: auto;
    z-index: 5;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

#lyrics-container::-webkit-scrollbar {
    display: none;
}

#lyrics-scroll {
    padding: 40vh 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.lyric-line {
    font-size: 1.6rem;
    text-align: center;
    padding: 6px 16px;
    border-radius: 6px;
    color: rgba(255, 255, 255, 0.35);
    transition: color 0.4s, text-shadow 0.4s, transform 0.3s;
    cursor: pointer;
    line-height: 1.4;
}

.lyric-line:hover {
    color: rgba(255, 255, 255, 0.6);
}

.lyric-line.active {
    color: #f1c40f;
    text-shadow: 0 0 20px rgba(241, 196, 15, 0.5);
    transform: scale(1.08);
    font-weight: bold;
}

.lyric-line.section-break {
    font-size: 1rem;
    color: rgba(231, 76, 60, 0.6);
    font-style: italic;
    cursor: default;
}

/* --- Controls --- */

#controls {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 18px 30px;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(10px);
}

#btn-play {
    background: #e74c3c;
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    font-size: 0.9rem;
    font-weight: bold;
    cursor: pointer;
    flex-shrink: 0;
    transition: background 0.2s, transform 0.1s;
}

#btn-play:hover {
    background: #c0392b;
    transform: scale(1.05);
}

#progress-bar {
    flex: 1;
    height: 6px;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 3px;
    cursor: pointer;
    position: relative;
}

#progress-fill {
    height: 100%;
    background: #e74c3c;
    border-radius: 3px;
    width: 0%;
    transition: width 0.1s linear;
}

#time-display {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.6);
    flex-shrink: 0;
    min-width: 100px;
    text-align: right;
}