I tried the following:
input[type="checkbox"]:disabled {
background-color:blue;
}
but it's not working.
form{
border:solid 2px darkblue;
width:60%;
padding-bottom:3%;
margin:0 auto;
}
#container{
display:flex;
flex-wrap:wrap;
justify-content:center;
margin:0 auto;
}
.info{
margin:2% 3%;
}
.contact{
display:flex;
flex-direction:column;
margin-bottom:1%;
width:50%;
font-size:1.5vw;
}
.alerts{
width:100%;
font-size:1.5vw;
text-align:left;
margin-left:3%;
color:red;
}
p.alerts{
text-align:center;
margin-top:1%;
margin-bottom:5%;
margin-left:0;
}
.hidden{
visibility:hidden;
}
.row{
display:flex;
justify-content:space-between;
width:80%;
margin:0 auto;
}
.col{
display:flex;
flex-direction:column;
}
#skippers{
display:flex;
flex-direction:row;
Justify-content:center;
align-items:center;
margin-bottom:3%;
}
.skippers{
margin: 0 3%;
}
input[type="checkbox"]:disabled {
background-color:blue;
}
input[type='submit']{
color:white;
background-color: blue;
font-weight:bold;
}
<h1>Registration</h1>
<form action='register.php' method='POST'>
<h2>Enter contact info</h2>
<div id='container'>
<div class='contact'>
<input class='info' type='text' name='fname' placeholder='first name'>
<span class='alerts hidden'>Please enter your first name</span>
</div>
<div class='contact'>
<input class='info' type='text' name='lname' placeholder='last name'>
<span class='alerts hidden'>Please enter your last name</span>
</div>
<div class='contact'>
<input class='info' type='tel' name='phone' placeholder='mobile phone number'>
<span class='alerts hidden'>Please enter your mobile phone number</span>
</div>
<div class='contact'>
<input class='info' type='email' name='email' placeholder='email'>
<span class='alerts hidden'>Please enter your email</span>
</div>
<div class='contact'>
<input class='info' type='password' name='password' placeholder='password'>
<span class='alerts hidden'>Please enter your password</span>
</div>
<div class='contact'>
<input class='info' type='password' name='confirm' placeholder='confirm password'>
<span class='alerts hidden'>Please enter your password</span>
</div>
</div>
<h2>Days available to sail</h2>
<div class='row'>
<div class='col'>
<label for="MO">M</label>
<input class='dow' type="checkbox" name="MO">
</div>
<div class='col'>
<label for="TU">T</label>
<input class='dow' type="checkbox" name="TU">
</div>
<div class='col'>
<label for="WE">W</label>
<input class='dow' type="checkbox" name="WE">
</div>
<div class='col'>
<label for="TH">T</label>
<input class='dow' type="checkbox" name="TH">
</div>
<div class='col'>
<label for="FR">F</label>
<input class='dow' type="checkbox" name="FR">
</div>
<div class='col'>
<label for="SA">S</label>
<input class='dow' type="checkbox" name="SA">
</div>
<div class='col'>
<label for="SU">S</label>
<input class='dow' type="checkbox" name="SU">
</div>
</div>
<p class='alerts hidden'>Please select at least 1 day</p>
<h2>Select Skippers</h2>
<div id='skippers'>
<p class='skippers'>David Cross</p>
<input class='skippers' type='checkbox' checked required disabled style="background-color:red">
</div>
<input type='submit' value = 'SUBMIT' name='mySubmit'>
</fom>
</div>
<script src="../public/js/register.js" type="text/javascript"></script>
</body>
</html>