body {
    margin: 0;
    padding: 0;
    height: 100vh;
    width: 100vw;
    box-sizing: border-box;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    touch-action: manipulation;
}

#feature-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
}

#feature-img {
    max-width: 60vw;
    max-height: 60vh;
    width: auto;
    height: auto;
    object-fit: contain;
    cursor: pointer;
    transition: filter 0.3s;
}

.corner-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 10;
    padding: 10px 20px;
    font-size: 1rem;
    border: none;
    border-radius: 5px;
    background: #333;
    color: #fff;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}