文件：static\css\checkbox.css

删除下面的代码

.checkbox-custom input[type=radio]:focus+label::before, .checkbox-custom input[type=checkbox]:focus+label::before {
    outline: thin dotted;
    outline: 0.36em auto -webkit-focus-ring-color;
    outline-offset: -2px;
}

文件：static\bootstrap\css\bootstrap.min.css

1.文件末尾添加以下代码

input[type=checkbox] {
    border-radius: .25em;
    width: 1em;
  height: 1em;
  vertical-align: top;
    margin-top: .25em;
  background-color: #fff;
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  border: 1px solid rgba(0, 0, 0, .25);
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  -webkit-print-color-adjust: exact;
  color-adjust: exact
}

input[type=radio] {
    border-radius: 50%;
    width: 1em;
  height: 1em;
  vertical-align: top;
    margin-top: .25em;
  background-color: #fff;
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  border: 1px solid rgba(0, 0, 0, .25);
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  -webkit-print-color-adjust: exact;
  color-adjust: exact
}

input:active {
    filter: brightness(90%)
}

input:focus {
    border-color: #86b7fe;
    outline: 0;
    box-shadow: 0 0 0 .25rem rgba(13, 110, 253, .25)
}

input:checked {
    background-color: #0d6efd;
    border-color: #0d6efd
}

input:checked[type=checkbox] {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'%3e%3cpath fill='none' stroke='%23fff' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='M6 10l3 3l6-6'/%3e%3c/svg%3e")
}

input:checked[type=radio] {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'%3e%3ccircle r='2' fill='%23fff'/%3e%3c/svg%3e")
}

input[type=checkbox]:indeterminate {
    background-color: #0d6efd;
    border-color: #0d6efd;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'%3e%3cpath fill='none' stroke='%23fff' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='M6 10h8'/%3e%3c/svg%3e")
}

input:disabled {
    pointer-events: none;
    filter: none;
    opacity: .5
}

input:disabled,input[disabled] {
    opacity: .5
}

2.删除以下代码即可

input[type="file"]:focus,
input[type="checkbox"]:focus,
input[type="radio"]:focus {
  outline: thin dotted;
  outline: 5px auto -webkit-focus-ring-color;
  outline-offset: -2px;
}