a {
    background: #5c6b73;
    border: 4px solid #111;
    border-radius: 4px;
    color: #eee;
    font-size: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    user-select: none;
    transition: background 0.1s, transform 0.05s;
    box-shadow: inset -4px -4px 0 rgba(0,0,0,0.3);
    text-decoration: none;
    underline: none;
}