@import url('https://fonts.googleapis.com/css2?family=Abril+Fatface&display=swap');

body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    background-color: #fff;
    overflow: hidden;
}

#tunnel {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100vw;
    height: 100vh;
    transform: translate(-50%, -50%);
    perspective: 1000px;
}

.frame {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 80vw;
    height: 80vh;
    border: 2px solid #000;
    box-shadow: 0 0 50px rgba(0,0,0,0.1);
    transform-origin: center center;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #fff;
}

/* Give alternating frames slightly different background to show depth better */
.frame:nth-child(even) {
    background: #f9f9f9;
}

.center-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-family: 'Abril Fatface', serif;
    font-size: 6rem;
    color: #000;
    pointer-events: none;
    z-index: 1000;
    mix-blend-mode: difference;
    color: #fff; /* renders as black against white */
}