html default select customization code example

Example 1: how to add a selection in css

.custom-select-wrapper {
     position: relative;
     user-select: none;
     width: 100%;
}
 .custom-select {
     position: relative;
     display: flex;
     flex-direction: column;
     border-width: 0 2px 0 2px;
     border-style: solid;
     border-color: #394a6d;
}
 .custom-select__trigger {
     position: relative;
     display: flex;
     align-items: center;
     justify-content: space-between;
     padding: 0 22px;
     font-size: 20px;
     font-weight: 300;
     color: #3b3b3b;
     height: 60px;
     line-height: 60px;
     background: #ffffff;
     cursor: pointer;
     border-width: 2px 0 2px 0;
     border-style: solid;
     border-color: #394a6d;
}
 .custom-options {
     position: absolute;
     display: block;
     top: 100%;
     left: 0;
     right: 0;
     border: 2px solid #394a6d;
     border-top: 0;
     background: #fff;
     transition: all 0.5s;
     opacity: 0;
     visibility: hidden;
     pointer-events: none;
     z-index: 2;
}
 .custom-select.open .custom-options {
     opacity: 1;
     visibility: visible;
     pointer-events: all;
}
 .custom-option {
     position: relative;
     display: block;
     padding: 0 22px 0 22px;
     font-size: 22px;
     font-weight: 300;
     color: #3b3b3b;
     line-height: 60px;
     cursor: pointer;
     transition: all 0.5s;
}
 .custom-option:hover {
     cursor: pointer;
     background-color: #b2b2b2;
}
 .custom-option.selected {
     color: #ffffff;
     background-color: #305c91;
}

Example 2: option select css

body {
    padding:50px;
    background-color:white;
}
.s-hidden {
    visibility:hidden;
    padding-right:10px;
}
.select {
    cursor:pointer;
    display:inline-block;
    position:relative;
    font:normal 11px/22px Arial, Sans-Serif;
    color:black;
    border:1px solid #ccc;
}
.styledSelect {
    position:absolute;
    top:0;
    right:0;
    bottom:0;
    left:0;
    background-color:white;
    padding:0 10px;
    font-weight:bold;
}
.styledSelect:after {
    content:"";
    width:0;
    height:0;
    border:5px solid transparent;
    border-color:black transparent transparent transparent;
    position:absolute;
    top:9px;
    right:6px;
}
.styledSelect:active, .styledSelect.active {
    background-color:#eee;
}
.options {
    display:none;
    position:absolute;
    top:100%;
    right:0;
    left:0;
    z-index:999;
    margin:0 0;
    padding:0 0;
    list-style:none;
    border:1px solid #ccc;
    background-color:white;
    -webkit-box-shadow:0 1px 2px rgba(0, 0, 0, 0.2);
    -moz-box-shadow:0 1px 2px rgba(0, 0, 0, 0.2);
    box-shadow:0 1px 2px rgba(0, 0, 0, 0.2);
}
.options li {
    padding:0 6px;
    margin:0 0;
    padding:0 10px;
}
.options li:hover {
    background-color:#39f;
    color:white;
}