silverstripe-simple/css/Form.css

.ui-widget, .ui-widget input, .ui-widget select, .ui-widget textarea, .ui-widget button {font-family:Arial, Helvetica, sans-serif !important;}
input:invalid, textarea:invalid {border-radius: 1px; -moz-box-shadow: 0px 0px 5px red; -webkit-box-shadow:0px 0px 5px red; box-shadow:0px 0px 5px red; }
.no-boxshadow input:invalid, .no-boxshadow textarea:invalid {background-color: #f0dddd;}

form .message {padding:6px 15px; border:1px solid;}
form .good {background-color:#ecf9d0; border-color:#8fbe00;}
form .bad {background-color:#f9d0d0; border-color:#be0000;}

.checkbox, .radio{margin-top:1px;}

#MemberLoginForm_LoginForm_action_dologin, #ExternalLoginForm_LoginForm_action_dologin, .Actions .action{padding:6px 20px;}
#MemberLoginForm_LoginForm{max-width:500px;}
#ForgotPassword a{margin-top:15px;}
#ForgotPassword {margin-top:6px;}

div.field{width:100%; float:left; margin-bottom:20px;}
.ui-widget{font-family:Arial, Helvetica, sans-serif;}
form label.left {float:left; width:25%; padding-right:5%; margin-top:4px; display:block; font-size:13px;}
form .middleColumn {float:right; width:70% !important;}
form .middleColumn .middleColumn{width:100% !important;}
.listbox option{padding:3px 0;}
form input.text, form textarea, form .textajaxuniquetext, form select{width:98%; padding:6px 1%; font-size:15px;}
form input.sitetreeurlsegment{width:200px;}
form span.readonly {font-size:16px;}

form input[disabled]{background-color:#f7f7f7; border:1px solid #dad9d9;}

form .creditCardField input, form input.currency {padding:5px 1%; width:50px;}
form input.numeric{padding:5px 1%; width:50px;}
form #DMYDate-month, form #DMYDate-day{width:25px;}
form .checkboxset li, form .optionset li{margin-bottom:5px;}

@media only screen and (max-width: 700px) {
form .middleColumn {float:right; width:100% !important;;}
form label.left, #MemberLoginForm_LoginForm label{margin-bottom:8px;}
}