Tab navigation animation | HTML, CSS & JavaScript

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: sans-serif;
}

body {
  background: #0f172a;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

/* Container */
.tabs-container {
  width: 600px;
}

/* Tabs */
.tabs {
  display: flex;
  position: relative;
  background: #1e293b;
  border-radius: 12px;
  padding: 5px;
}

/* Tab Button */
.tab {
  flex: 1;
  padding: 12px;
  text-align: center;
  cursor: pointer;
  position: relative;
  z-index: 2;
  transition: 0.3s;
}

.tab:hover {
  color: #38bdf8;
}

/* Active Tab */
.tab.active {
  color: white;
}

/* Sliding Indicator */
.indicator {
  position: absolute;
  height: 100%;
  width: 33.33%;
  background: linear-gradient(135deg, #38bdf8, #6366f1);
  border-radius: 10px;
  top: 0;
  left: 0;
  transition: transform 0.4s ease;
  z-index: 1;
}

/* Content */
.content {
  margin-top: 20px;
  padding: 20px;
  background: #1e293b;
  border-radius: 12px;
  overflow: hidden;
  position: relative;
}

/* Tab Content */
.tab-content {
  position: absolute;
  width: 100%;
  opacity: 0;
  transform: translateY(20px);
  transition: 0.4s ease;
}

.tab-content.active {
  position: relative;
  opacity: 1;
  transform: translateY(0);
}

- Tab navigation animation

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