JSFiddle - React, Tailwind, and code Playground
by bluetidepro
HTML
<a href="#" class="a_button">A</a>
<a href="#" class="b_button">B</a>
<a href="#" class="c_button">C</a>
<a href="#" class="d_button">D</a>
<a href="#" class="f_button">F</a>
CSS
body{margin:10px;}
.a_button, .b_button, .c_button, .d_button, .f_button{
display:block;
width:25px;
height:25px;
font-size:16px;
font-weight:bold;
font-family:"Helvetica Neue",Helvetica,Arial,sans-serif;
color:#fff;
line-height:21px;
text-align:center;
background:#75ae02;
-moz-border-radius:50px;
-webkit-border-radius:50px;
border-radius:50px;
-khtml-border-radius:50px;
text-decoration:none;
text-shadow:1px 1px 0 #000;
}
.b_button{background:#4c7000;}
.c_button, .d_button{background:#454545;}
.f_button{background:#181818;}
.a_button:hover, .b_button:hover, .c_button:hover, .d_button:hover, .f_button:hover{
-ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";
filter: alpha(opacity=50);
-moz-opacity:0.5;
-khtml-opacity 0.5;
opacity:0.5;
}