:root {
    --bg-color: #064f34; 
    --text-color: #FFFFFF; 
    --accent-color: #D64933; 
}

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

body::before {
    content: "";
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
    opacity: 0.15; 
    mix-blend-mode: overlay;
    z-index: 50; 
    pointer-events: none; 
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Special Elite', cursive;
    height: 100vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

#canvas-container { position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: 1; }

.main-ui { position: relative; z-index: 10; text-align: center; pointer-events: none; }

.central-stack { display: flex; flex-direction: column; justify-content: center; align-items: center; gap: 5px; }

h1.large-chilimangiaro {
    font-size: clamp(3rem, 10vw, 6rem);
    line-height: 1;
    margin-bottom: 0;
    letter-spacing: 2px;
    color: var(--accent-color);
    text-shadow: 0 0 30px rgba(214, 73, 51, 0.2); 
}

.tagline {
    font-size: 1rem; 
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--text-color);
    padding: 10px 20px;
    display: inline-block;
    line-height: 1.4;
}

.mobile-text { display: none; }
.desktop-text { display: inline; }

.volcano-sound-container {
    position: fixed;
    bottom: 20vh; 
    left: 50%;
    transform: translateX(-50%);
    z-index: 20;
    pointer-events: auto; 
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* BOTTONE CON FRAME FISSO */
#magma-sound-btn {
    padding: 12px 30px;
    min-width: 280px; /* DIMENSIONE FISSA: Impedisce il sussulto del frame */
    background-color: transparent !important;
    border: 2px solid var(--accent-color) !important;
    color: var(--accent-color) !important;
    font-family: 'Special Elite', cursive !important;
    font-size: 1rem;
    letter-spacing: 3px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    border-radius: 0 !important;
    outline: none;
}

#magma-sound-btn:hover, #magma-sound-btn.playing {
    background-color: rgba(214, 73, 51, 0.15) !important;
    box-shadow: 0 0 20px rgba(214, 73, 51, 0.5);
}

#magma-sound-btn.playing {
    animation: pulse-magma 2s infinite;
    text-shadow: 0 0 10px rgba(214, 73, 51, 0.8);
}

@keyframes pulse-magma {
    0% { box-shadow: 0 0 5px rgba(214, 73, 51, 0.2); }
    50% { box-shadow: 0 0 25px rgba(214, 73, 51, 0.6); }
    100% { box-shadow: 0 0 5px rgba(214, 73, 51, 0.2); }
}

/* TRACK CREDITS CON OPACITY DINAMICA */
.track-credits {
    font-size: 0.65rem;
    color: var(--text-color);
    opacity: 0.15; /* PENOMBRA INIZIALE */
    margin-top: 15px;
    letter-spacing: 2px;
    text-transform: uppercase;
    text-align: center;
    transition: opacity 0.8s ease; /* Transizione fluida */
}

.track-credits.active {
    opacity: 1; /* LUCE PURA ALL'ATTIVAZIONE */
}

footer {
    position: fixed; bottom: 0; left: 0; width: 100%;
    padding: 30px 40px;
    display: flex;
    justify-content: space-between; 
    align-items: flex-end;
    z-index: 20;
    pointer-events: none; 
}

.footer-block { pointer-events: auto; }

.footer-link {
    color: var(--text-color); text-decoration: none; font-size: 1.1rem;
    transition: all 0.3s ease; display: flex; align-items: center; gap: 10px;
}
.footer-link:hover { color: var(--accent-color); transform: translateY(-3px); }

.serial-number {
    position: fixed; top: 30px; left: 0; width: 100%; text-align: center;
    font-size: 0.8rem; color: var(--text-color); opacity: 0.5; letter-spacing: 2px;
    z-index: 20; pointer-events: none;
}

@media (max-width: 768px) {
    .mobile-text { display: inline; }
    .desktop-text { display: none; }
    h1.large-chilimangiaro { line-height: 0.85; margin-bottom: 15px; }
    footer {
        display: flex; flex-direction: column; align-items: center; gap: 20px; padding: 20px;
        text-align: center;
    }
    .footer-link { font-size: 0.9rem; }
    .volcano-sound-container { bottom: 25vh; }
    #magma-sound-btn { min-width: 240px; } /* Leggermente più piccolo su mobile */
}