CSS Navigation dropdown menu | HTML, CSS & JavaScript

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

body {
      min-height: 100vh;
      display: flex;
      justify-content: center;
      align-items: flex-start;
      background: linear-gradient(135deg, #0f172a, #1e293b, #0f172a);
      padding-top: 80px;
    }

/* Navigation */

nav {
      width: 1000px;
      background: rgba(255, 255, 255, .08);
      backdrop-filter: blur(15px);
      border: 1px solid rgba(255, 255, 255, .12);
      border-radius: 50px;
      padding: 10px 20px;
      box-shadow:
        0 20px 40px rgba(0, 0, 0, .35);
      margin: 50px;
    }

.menu {
      display: flex;
      justify-content: center;
      list-style: none;
    }

.menu>li {
      position: relative;
      margin: 0 8px;
    }

.menu>li>a {
      display: block;
      padding: 16px 24px;
      color: #fff;
      text-decoration: none;
      font-size: 15px;
      font-weight: 500;
      border-radius: 40px;
      transition: .35s;
      position: relative;
      overflow: hidden;
    }

/* Hover Background */

.menu>li>a::before {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, #06b6d4, #3b82f6);
      transform: scaleX(0);
      transform-origin: left;
      transition: .4s;
      z-index: -1;
      border-radius: 40px;
    }

.menu>li:hover>a::before {
      transform: scaleX(1);
    }

.menu>li:hover>a {
      color: #fff;
    }

/* Dropdown */

.dropdown {
      position: absolute;
      top: 75px;
      left: 50%;
      transform: translateX(-50%) translateY(25px);
      min-width: 220px;
      background: rgba(255, 255, 255, .08);
      backdrop-filter: blur(18px);
      border: 1px solid rgba(255, 255, 255, .1);
      border-radius: 18px;
      list-style: none;
      opacity: 0;
      visibility: hidden;
      transition: .4s;
      box-shadow: 0 20px 40px rgba(0, 0, 0, .35);
    }
    .menu li:hover .dropdown {
      opacity: 1;
      visibility: visible;
      transform: translateX(-50%) translateY(0);
      z-index: 1;
    }

.dropdown li {
      border-bottom: 1px solid rgba(255, 255, 255, .08);
    }

.dropdown li:last-child {
      border: none;
    }

.dropdown a {
      display: block;
      color: #fff;
      text-decoration: none;
      padding: 14px 20px;
      transition: .35s;
    }

.dropdown a:hover {
      padding-left: 30px;
      background: rgba(255, 255, 255, .08);
      color: #4fd1ff;
    }

/* Small Arrow */

.dropdown::before {
      content: "";
      position: absolute;
      top: -8px;
      left: 50%;
      transform: translateX(-50%) rotate(45deg);
      width: 16px;
      height: 16px;
      background: rgba(255, 255, 255, .08);
      border-left: 1px solid rgba(255, 255, 255, .1);
      border-top: 1px solid rgba(255, 255, 255, .1);
    }

/* Underline Animation */

.menu>li>a::after {
      content: "";
      position: absolute;
      left: 50%;
      bottom: 8px;
      width: 0;
      height: 2px;
      background: #fff;
      transition: .4s;
      transform: translateX(-50%);
    }

.menu>li:hover>a::after {
      width: 60%;
    }

/* Demo */

.hero {
      color: white;
      text-align: center;
      width: 600px;
    }

.hero h1 {
      font-size: 60px;
      font-weight: 700;
      margin-bottom: 20px;
      color: #434747;
    }

.hero p {
      opacity: .7;
      font-size: 18px;
      color: #434747;
    }

- CSS Navigation dropdown menu

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