Notification Badge — StealThis.dev

代码

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #f9fafb;
  color: #111;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.demo {
  background: #fff;
  border-radius: 20px;
  padding: 32px;
  border: 1px solid #e5e7eb;
  width: 360px;
}

.section-label {
  font-size: 12px;
  font-weight: 700;
  color: #9ca3af;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 16px;
}

.section-label + .section-label,
.row + .section-label {
  margin-top: 28px;
}

.row {
  display: flex;
  gap: 28px;
  align-items: flex-end;
  flex-wrap: wrap;
}

.badge-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.demo-caption {
  font-size: 11px;
  color: #9ca3af;
}

/* Icon button */
.icon-btn {
  position: relative;
  width: 44px;
  height: 44px;
  border: 1.5px solid #e5e7eb;
  background: #fff;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #374151;
  transition: background 0.15s, border-color 0.15s;
}
.icon-btn:hover {
  background: #f9fafb;
  border-color: #d1d5db;
}

/* Base badge */
.badge {
  position: absolute;
  top: -5px;
  right: -5px;
  border: 2px solid #fff;
  border-radius: 999px;
}

/* Dot */
.badge-dot {
  width: 10px;
  height: 10px;
  background: #ef4444;
}

.badge-dot--warning {
  background: #f59e0b;
}

/* Pulse ring */
.badge-dot--pulse::before {
  content: "";
  position: absolute;
  inset: -3px;
  border-radius: 50%;
  border: 2px solid #ef4444;
  animation: pulse-ring 1.4s ease-out infinite;
}

@keyframes pulse-ring {
  0% {
    transform: scale(0.9);
    opacity: 1;
  }
  70% {
    transform: scale(1.8);
    opacity: 0;
  }
  100% {
    transform: scale(0.9);
    opacity: 0;
  }
}

/* Numeric */
.badge-count {
  min-width: 18px;
  height: 18px;
  background: #ef4444;
  color: #fff;
  font-size: 10px;
  font-weight: 800;
  padding: 0 4px;
  line-height: 14px;
  text-align: center;
}

.badge--overflow {
  min-width: 24px;
  font-size: 9px;
}

/* Color variants */
.badge--blue {
  background: #6366f1;
}
.badge--green {
  background: #16a34a;
}
.badge--amber {
  background: #d97706;
}

/* Hidden state */
.badge.hidden {
  transform: scale(0);
  transition: transform 0.2s;
}

const clearBtn = document.getElementById("clearBtn");
const clearBadge = document.getElementById("clearBadge");

clearBtn.addEventListener("click", () => {
  clearBadge.classList.add("hidden");
  setTimeout(() => clearBadge.remove(), 200);
});

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>Notification Badge</title>
  <link rel="stylesheet" href="style.css" />
</head>
<body>
<div class="demo">
  <h2 class="section-label">Dot indicator</h2>
  <div class="row">
    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-dot"></span>
      </button>
      <span class="demo-caption">dot</span>
    </div>

    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z"/></svg>
        <span class="badge badge-dot badge-dot--pulse"></span>
      </button>
      <span class="demo-caption">pulse</span>
    </div>

    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="12" r="10"/><line x1="12" y1="8" x2="12" y2="12"/><line x1="12" y1="16" x2="12.01" y2="16"/></svg>
        <span class="badge badge-dot badge-dot--warning"></span>
      </button>
      <span class="demo-caption">warning</span>
    </div>
  </div>

  <h2 class="section-label">Numeric counter</h2>
  <div class="row">
    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-count">1</span>
      </button>
      <span class="demo-caption">1</span>
    </div>

    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z"/></svg>
        <span class="badge badge-count">12</span>
      </button>
      <span class="demo-caption">12</span>
    </div>

    <div class="badge-wrap">
      <button class="icon-btn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="12" r="10"/><line x1="12" y1="8" x2="12" y2="12"/><line x1="12" y1="16" x2="12.01" y2="16"/></svg>
        <span class="badge badge-count badge--overflow">99+</span>
      </button>
      <span class="demo-caption">99+</span>
    </div>
  </div>

  <h2 class="section-label">Color variants</h2>
  <div class="row">
    <div class="badge-wrap">
      <button class="icon-btn"><svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-count badge--blue">4</span></button>
      <span class="demo-caption">info</span>
    </div>
    <div class="badge-wrap">
      <button class="icon-btn"><svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-count badge--green">7</span></button>
      <span class="demo-caption">success</span>
    </div>
    <div class="badge-wrap">
      <button class="icon-btn"><svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-count badge--amber">2</span></button>
      <span class="demo-caption">warning</span>
    </div>
  </div>

  <h2 class="section-label">Interactive — click to clear</h2>
  <div class="row">
    <div class="badge-wrap">
      <button class="icon-btn" id="clearBtn">
        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"/><path d="M13.73 21a2 2 0 0 1-3.46 0"/></svg>
        <span class="badge badge-count badge-dot--pulse" id="clearBadge">5</span>
      </button>
      <span class="demo-caption">click to clear</span>
    </div>
  </div>
</div>
<script src="script.js"></script>
</body>
</html>

Collection of notification badge variants — dot indicator, numeric counter, 99+ overflow, animated pulse ring, and colored status variants. All CSS-only, no JavaScript required.