#principal {
    background-color: #4CFC68;

    background-position: bottom;
    background-size: 9vh;
    
    
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    /*width: 100vw;*/
    /*transition: all cubic-bezier(0.075, 0.82, 0.165, 1) 5s;*/
}
#bottom_grass {
    --var-size : 7vh;
    background-image: url('/sprit/back_line_end2.svg');
    background-repeat: repeat-x;
    width: 100%;
    background-size: var(--var-size);
    height: var(--var-size);
}

@media screen and (max-width: 810px) {
    #principal {
        flex-direction: column;
    }
}