css制作角标

使用伪元素创建角标

通过 ::before 或 ::after 伪元素生成角标，结合绝对定位调整位置：

.element {
  position: relative;
  display: inline-block;
}
.element::after {
  content: "NEW";
  position: absolute;
  top: -5px;
  right: -10px;
  background: red;
  color: white;
  font-size: 12px;
  padding: 2px 5px;
  border-radius: 3px;
}

利用 transform 实现偏移

通过旋转和位移创造斜角效果：

.badge {
  display: inline-block;
  background: #ff4757;
  color: white;
  padding: 2px 8px;
  transform: rotate(15deg) translate(5px, -5px);
}

圆形数字角标

适合未读消息等数字提示：

.notification {
  position: relative;
}
.notification::after {
  content: "5";
  position: absolute;
  top: -8px;
  right: -8px;
  width: 18px;
  height: 18px;
  background: #3498db;
  border-radius: 50%;
  color: white;
  text-align: center;
  line-height: 18px;
  font-size: 12px;
}

边框角标样式

结合边框和伪元素创建贴边角标：

.ribbon {
  position: relative;
  overflow: hidden;
}
.ribbon::before {
  content: "HOT";
  position: absolute;
  top: 10px;
  right: -25px;
  width: 100px;
  padding: 3px 0;
  background: #ff6b6b;
  color: white;
  text-align: center;
  transform: rotate(45deg);
  box-shadow: 0 0 10px rgba(0,0,0,0.2);
}

使用 CSS 变量动态控制

通过变量实现可配置化角标：

:root {
  --badge-color: #e74c3c;
  --badge-size: 20px;
}
.dynamic-badge {
  --badge-content: "!";
  position: relative;
}
.dynamic-badge::after {
  content: var(--badge-content);
  position: absolute;
  top: calc(var(--badge-size) / -2);
  right: calc(var(--badge-size) / -2);
  width: var(--badge-size);
  height: var(--badge-size);
  background: var(--badge-color);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: calc(var(--badge-size) * 0.6);
}