.envelope {
    position: relative;
    display: inline-block;
    width: 1.8rem;
    height: 1.2rem;
    background-color:#502b16;
    border: 1px solid black;
    margin: 0 5px 0 0;
}

.arrow {
    display: block;
    position: absolute;
    background-color: transparent;
    border: solid #f1f1e6;
    border-width: 0 2px 2px 0;
    width: 0.3rem;
    height: 0.3rem;
    padding: 0.5rem;
    transform: rotate(45deg);
    -webkit-transform: rotate(45deg);
    z-index:1;
    left: 4px;
    top: -0.55rem;
}