how to make a customized select tag code example
Example 1: select button style
.select-css {
display: block;
font-size: 16px;
font-family: sans-serif;
font-weight: 700;
color: #444;
line-height: 1.3;
padding: .6em 1.4em .5em .8em;
width: 100%;
max-width: 100%;
box-sizing: border-box;
margin: 0;
border: 1px solid #aaa;
box-shadow: 0 1px 0 1px rgba(0,0,0,.04);
border-radius: .5em;
-moz-appearance: none;
-webkit-appearance: none;
appearance: none;
background-color: #fff;
background-image: url('data:image/svg+xml;charset=US-ASCII,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%22292.4%22%20height%3D%22292.4%22%3E%3Cpath%20fill%3D%22%23007CB2%22%20d%3D%22M287%2069.4a17.6%2017.6%200%200%200-13-5.4H18.4c-5%200-9.3%201.8-12.9%205.4A17.6%2017.6%200%200%200%200%2082.2c0%205%201.8%209.3%205.4%2012.9l128%20127.9c3.6%203.6%207.8%205.4%2012.8%205.4s9.2-1.8%2012.8-5.4L287%2095c3.5-3.5%205.4-7.8%205.4-12.8%200-5-1.9-9.2-5.5-12.8z%22%2F%3E%3C%2Fsvg%3E'),
linear-gradient(to bottom, #ffffff 0%,#e5e5e5 100%);
background-repeat: no-repeat, repeat;
background-position: right .7em top 50%, 0 0;
background-size: .65em auto, 100%;
}
.select-css::-ms-expand {
display: none;
}
.select-css:hover {
border-color: #888;
}
.select-css:focus {
border-color: #aaa;
box-shadow: 0 0 1px 3px rgba(59, 153, 252, .7);
box-shadow: 0 0 0 3px -moz-mac-focusring;
color: #222;
outline: none;
}
.select-css option {
font-weight:normal;
}
*[dir="rtl"] .select-css, :root:lang(ar) .select-css, :root:lang(iw) .select-css {
background-position: left .7em top 50%, 0 0;
padding: .6em .8em .5em 1.4em;
}
.select-css:disabled, .select-css[aria-disabled=true] {
color: graytext;
background-image: url('data:image/svg+xml;charset=US-ASCII,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%22292.4%22%20height%3D%22292.4%22%3E%3Cpath%20fill%3D%22graytext%22%20d%3D%22M287%2069.4a17.6%2017.6%200%200%200-13-5.4H18.4c-5%200-9.3%201.8-12.9%205.4A17.6%2017.6%200%200%200%200%2082.2c0%205%201.8%209.3%205.4%2012.9l128%20127.9c3.6%203.6%207.8%205.4%2012.8%205.4s9.2-1.8%2012.8-5.4L287%2095c3.5-3.5%205.4-7.8%205.4-12.8%200-5-1.9-9.2-5.5-12.8z%22%2F%3E%3C%2Fsvg%3E'),
linear-gradient(to bottom, #ffffff 0%,#e5e5e5 100%);
}
.select-css:disabled:hover, .select-css[aria-disabled=true] {
border-color: #aaa;
}
body {
margin: 2rem;
}
//html
<select class="select-css">
<option>This is a native select element</option>
<option>Apples</option>
<option>Bananas</option>
<option>Grapes</option>
<option>Oranges</option>
</select>
Example 2: how to add a selection in css
*, *:after, *:before {
box-sizing: border-box;
}