  * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      font-family: 'Poppins', sans-serif;
    }

    body {
      min-height: 100vh;
      background: linear-gradient(to right, #0f2027, #3e5a63, #31434b);
      display: flex;
      align-items: center;
      justify-content: center;
      padding: 20px;
      color: #FEEBF6;
    }

    .wrapper {
      width: 100%;
      max-width: 380px;
      background: #1f4037;
      background: linear-gradient(to right, #4ca1af, #2c3e50);
      border-radius: 15px;
      padding: 30px 25px;
      box-shadow: 0 15px 30px rgba(0,0,0,0.3);
    }

    .heading h1 {
      font-size: 1.8em;
      text-align: center;
      font-weight: 600;
      margin-bottom: 20px;
      color: #fff;
    }

    .form-group {
      display: flex;
      flex-direction: column;
      gap: 5px;
      margin-bottom: 15px;
    }

    label {
      font-size: 1rem;
      color: #f0f0f0;
    }

    input[type="date"] {
      padding: 10px;
      border: none;
      border-radius: 6px;
      font-size: 1rem;
      background-color: #fff;
      color: #333;
    }

    .btn {
      display: flex;
      justify-content: space-between;
      gap: 10px;
      margin: 20px 0;
    }

    .btn button {
      flex: 1;
      padding: 12px;
      border: none;
      border-radius: 6px;
      background-color: #5a8872;
      color: #fff;
      font-size: 1rem;
      font-weight: 500;
      cursor: pointer;
      transition: background 0.3s ease;
    }

    .btn button:hover {
      background-color: #46695d;
    }

    .btn i {
      margin-right: 5px;
    }

    .heading-calculate,
    .calculate_date_of_borth {
      display: flex;
      justify-content: space-between;
      margin-top: 10px;
      gap: 10px;
    }

    .heading-calculate span,
    .calculate_date_of_borth p {
      flex: 1;
      text-align: center;
    }

    .calculate_date_of_borth p {
      background-color: #ffffff1a;
      padding: 12px;
      border-radius: 8px;
      font-size: 1.1rem;
      color: #fff;
    }

    @media screen and (max-width: 600px) {
      .wrapper {
        padding: 20px 15px;
      }

      .heading h1 {
        font-size: 1.4em;
      }

      .btn button {
        font-size: 0.9rem;
        padding: 10px;
      }
    }