i.iconfont.icon-shell:before {
    content: "";
    display: block;
    width: 60px;
    height: 60px;
    margin: 0 auto;
    margin-top: 20px;
    background: url(shell.png) center no-repeat;
    background-size: contain;
}
i.iconfont.icon-index:before {
    content: "";
    display: block;
    width: 60px;
    height: 60px;
    margin: 0 auto;
    margin-top: 20px;
    background: url(index.png) center no-repeat;
    background-size: contain;
}
i.iconfont.icon-pypi:before {
    content: "";
    display: block;
    width: 60px;
    height: 60px;
    margin: 0 auto;
    margin-top: 20px;
    background: url(PYPI.png) center no-repeat;
    background-size: contain;
}
i.iconfont.icon-ssh:before {
    content: "";
    display: block;
    width: 60px;
    height: 60px;
    margin: 0 auto;
    margin-top: 20px;
    background: url(ssh.png) center no-repeat;
    background-size: contain;
}
i.iconfont.icon-qa:before {
    content: "";
    display: block;
    width: 60px;
    height: 60px;
    margin: 0 auto;
    margin-top: 20px;
    background: url(qa.png) center no-repeat;
    background-size: contain;
}