antd-mobile/es/components/form/form-item.css

<img src="https://gw.alipayobjects.com/mdn/rms_ee68a8/afts/img/A*hjjDS5Yy-ooAAAAAAAAAAAAAARQnAQ" alt="logo" width="100%" />

.adm-form-item + .adm-form-item {
  border-top: none;
}
.adm-form-item-label {
  display: block;
  height: 100%;
  line-height: 1.5;
  box-sizing: border-box;
  position: relative;
  color: #666666;
}
.adm-form-item-label .adm-form-item-required-asterisk {
  position: absolute;
  left: -0.6em;
  top: 0;
  font-family: SimSun, sans-serif;
  color: var(--adm-color-danger);
  user-select: none;
}
.adm-form-item-label .adm-form-item-required-text {
  margin-left: 4px;
  color: var(--adm-color-weak);
}
.adm-form-item-label-help {
  margin-left: 4px;
  cursor: pointer;
}
.adm-form-item-child {
  display: flex;
}
.adm-form-item-child-position-normal {
  justify-content: normal;
}
.adm-form-item-child-position-normal > * {
  flex: auto;
}
.adm-form-item-child-position-right {
  justify-content: right;
}
.adm-form-item-child-position-right > * {
  flex: none;
}
.adm-form-item-feedback-error {
  color: var(--adm-color-danger);
  margin-top: 4px;
}
.adm-form-item-feedback-warning {
  color: var(--adm-color-warning);
  margin-top: 4px;
}
.adm-form-item.adm-form-item-hidden {
  display: none;
}
.adm-form-item.adm-form-item-horizontal.adm-list-item {
  --align-items: stretch;
  --prefix-width: 6em;
}
.adm-form-item.adm-form-item-horizontal .adm-list-item-content-prefix {
  padding-top: 12px;
  padding-bottom: 12px;
}
.adm-form-item.adm-form-item-horizontal .adm-list-item-content-extra {
  align-self: center;
}
.adm-form-item.adm-form-item-vertical .adm-form-item-label {
  font-size: 15px;
  margin-bottom: 4px;
}