antd-mobile/es/components/passcode-input/passcode-input.css

<div align="center">

.adm-passcode-input {
  position: relative;
  display: inline-block;
  --cell-size: 40px;
  --cell-gap: 6px;
  --dot-size: 10px;
  --border-color: var(--adm-color-border);
  --border-radius: 8px;
}
.adm-passcode-input-cell-container {
  display: inline-flex;
  vertical-align: top;
}
.adm-passcode-input-cell {
  flex: none;
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  font-size: var(--adm-font-size-10);
  width: var(--cell-size);
  height: var(--cell-size);
  background: var(--adm-color-background);
}
.adm-passcode-input:not(.adm-passcode-input-seperated) {
  border-radius: var(--border-radius);
  overflow: hidden;
  border: 1px solid var(--border-color);
}
.adm-passcode-input:not(.adm-passcode-input-seperated) .adm-passcode-input-cell:not(:last-child) {
  border-right: 1px solid var(--border-color);
}
.adm-passcode-input:not(.adm-passcode-input-seperated).adm-passcode-input-focused {
  border-color: var(--adm-color-primary);
  box-shadow: 0 0 2px 0 var(--adm-color-primary);
  outline: none;
}
.adm-passcode-input:not(.adm-passcode-input-seperated).adm-passcode-input-error {
  border-color: var(--adm-color-danger);
  box-shadow: 0 0 2px 0 var(--adm-color-danger);
  animation: 100ms ease-in-out 0s 3 normal none running adm-shake-horizontal;
}
.adm-passcode-input.adm-passcode-input-seperated .adm-passcode-input-cell {
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}
.adm-passcode-input.adm-passcode-input-seperated .adm-passcode-input-cell:not(:last-child) {
  margin-right: var(--cell-gap);
}
.adm-passcode-input.adm-passcode-input-seperated .adm-passcode-input-cell-focused {
  border-color: var(--adm-color-primary);
  box-shadow: 0 0 2px 0 var(--adm-color-primary);
}
.adm-passcode-input-seperated.adm-passcode-input-focused {
  outline: none;
}
.adm-passcode-input.adm-passcode-input-seperated.adm-passcode-input-error {
  animation: 100ms ease-in-out 0s 3 normal none running adm-shake-horizontal;
}
.adm-passcode-input.adm-passcode-input-seperated.adm-passcode-input-error .adm-passcode-input-cell {
  border-color: var(--adm-color-danger);
  box-shadow: 0 0 2px 0 var(--adm-color-danger);
}
.adm-passcode-input-cell-dot::before {
  content: '';
  width: var(--dot-size);
  height: var(--dot-size);
  border-radius: 100%;
  background: var(--adm-color-text);
}
.adm-passcode-input-cell-caret::after {
  content: '';
  width: 2px;
  height: 1.1em;
  margin-left: 1px;
  background: var(--adm-color-primary);
  animation: 1s linear infinite adm-caret-blink;
}
.adm-passcode-input > .adm-passcode-input-native-input {
  position: absolute;
  left: -200vw;
  top: 0;
  display: block;
  width: 50px;
  height: 20px;
  opacity: 0.5;
}
@keyframes adm-shake-horizontal {
  0% {
    transform: translateX(0);
  }
  10% {
    transform: translateX(-4px);
  }
  20% {
    transform: translateX(5px);
  }
  30% {
    transform: translateX(-1px);
  }
  40% {
    transform: translateX(8px);
  }
  50% {
    transform: translateX(0);
  }
  60% {
    transform: translateX(-8px);
  }
  70% {
    transform: translateX(1px);
  }
  80% {
    transform: translateX(-5px);
  }
  90% {
    transform: translateX(4px);
  }
  100% {
    transform: translateX(0);
  }
}
@keyframes adm-caret-blink {
  from {
    opacity: 1;
  }
  60% {
    opacity: 1;
  }
  80% {
    opacity: 0;
  }
  to {
    opacity: 0;
  }
}