/* Make all form labels bold */
form.webform-submission-form label {
  font-weight: bold;
}

/* If specific classes are used, target them */
form.webform-submission-form .form-item label {
  font-weight: bold;
}

/* Specific rules for radio and checkbox labels */
form.webform-submission-form .form-radios label,
form.webform-submission-form .form-checkboxes label {
  font-weight: bold;
}

/* Ensure the options are not bold if that is the desired look */
form.webform-submission-form .form-radios .option,
form.webform-submission-form .form-checkboxes .option {
  font-weight: normal;
}