html, body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    height: 100%;
    touch-action: none;
}

.mobile-wrapper {
    width: 100%;                       /* Take full screen width */
    max-width: 430px;                   /* Original mobile width */
    aspect-ratio: 1452 / 2602;          /* Match bg.jpg ratio */
    margin: 0 auto;                     /* Center on PC */
    position: relative;
    background: #000;
    overflow: hidden;
}

#bg {
    width: 100%;
    height: 100%;
    object-fit: contain;
    object-position: top center;
    display: block;
    background-color: #000;
}

.redirect-btn {
    position: absolute;
    bottom: 42%;   /* same as your desired placement */
    left: 52%;
    transform: translateX(-50%);
}

.redirect-btn img {
    width: 50%;    /* relative to wrapper width */
    height: auto;
    animation: pulse 1s infinite linear;
}

@keyframes pulse {
    0% { transform: scale(0.9); }
    50% { transform: scale(1.1); }
    100% { transform: scale(0.9); }
}