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

button{
    outline: none;
    border: none;
    cursor: pointer;
}

.m-auto{
    margin: 0 auto;
}


/* position */

.relative {
    position: relative;
}

.absolute {
    position: absolute;
}

.fixed {
    position: fixed;
}

.sticky {
    position: sticky;
}

.static {
    position: static;
}