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

.app {
    z-index: 2;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    text-align: center;
    font-family: 'Kanit', sans-serif;
    font-size: 3vh;
}

.btn {
    display: inline-block;
    outline: none;
    border: white 2px solid;
    border-radius: 10px;
    background: unset;
    color: white;
    font-size: 3vh;
    padding: 5px 50px;
    cursor: pointer;
    text-decoration: none;
    margin-top: 20px;
}
.btn:hover{
    background-color: white;
    transition: .5s;
    color: black;
}