:root {
    --button:#B1D3A5;
    --button-shadow:#659226;
}

.btn,
button {
    postion: relative;
    display: inline-block;
    cursor: pointer;
    font-size: inherit;
    font-family: inherit;
    padding: 0.25em 0.5em;
    margin: 0.25em;
    border: 0;
    border-radius: 0.75em;
    font-weight: 500;
    transition: 0.3s;
    background-color: var(--button);
    box-shadow: 0 6px 0 var(--button-shadow);
}

.btn:hover,
button:hover {
    transform: translateY(2px);
    box-shadow: 0 4px 0 var(--button-shadow);
}

.btn:active,
button:active {
    transform: translateY(5px);
    box-shadow: 0 3px 0 var(--button-shadow);
}