:root {
    --bg-color: #050505;
    --text-color: #d0d0d0;
    --accent-color: #880000;
}

body,
html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'serif';
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

#container {
    text-align: center;
    max-width: 600px;
    padding: 20px;
    transition: opacity 2s;
}

h1 {
    font-size: 2rem;
    letter-spacing: 0.5rem;
    margin-bottom: 2rem;
    color: var(--accent-color);
    text-shadow: 0 0 10px rgba(136, 0, 0, 0.5);
}

.warning {
    font-size: 1.2rem;
    margin-bottom: 3rem;
    line-height: 1.6;
}

#start-btn {
    background: transparent;
    color: var(--text-color);
    border: 1px solid var(--text-color);
    padding: 15px 40px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: all 0.5s;
}

#start-btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.2);
}

#darkness {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: black;
    display: none;
    opacity: 0;
    transition: opacity 5s;
    z-index: 100;
    cursor: none;
}

#heartbeat-visual {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 2px;
    height: 2px;
    background: rgba(136, 0, 0, 0.5);
    border-radius: 50%;
    pointer-events: none;
}

.pulse {
    animation: pulse-anim 1s infinite;
}

@keyframes pulse-anim {
    0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.5;
    }

    50% {
        transform: translate(-50%, -50%) scale(50);
        opacity: 0;
    }

    100% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0;
    }
}

#subtitles {
    position: fixed;
    bottom: 10%;
    width: 100%;
    text-align: center;
    font-size: 1.5rem;
    color: rgba(255, 255, 255, 0.1);
    pointer-events: none;
    z-index: 101;
}