styles.css

body {
    margin: 0;
    margin-top: 1rem;
    display: flex;
    justify-content: center;
  }
  
  .date-picker-container {
    position: relative;
    display: inline-block;
  }
  
  .date-picker-button {
    cursor: pointer;
  }
  
  .date-picker {
    display: none;
    position: absolute;
    margin-top: 1rem;
    top: 100%;
    transform: translateX(-50%);
    left: 50%;
    padding: .5rem;
    border-radius: .5rem;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05), 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06), 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    background-color: white;
  }
  
  .date-picker-header {
    display: flex;
    justify-content: space-between;
    font-weight: bold;
    font-size: .8rem;
    align-items: center;
  }
  
  .date-picker-grid {
    display: grid;
    gap: .5rem;
    grid-template-columns: repeat(7, 2rem);
    grid-auto-rows: 2rem;
  }
  
  .date-picker-grid > * {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    height: 100%;
  }
  
  .date-picker-grid-header {
    font-weight: bold;
    font-size: .75rem;
    color: #333;
  }
  
  .date-picker-grid-dates {
    color: #555;
  }
  
  .date-picker-other-month-date {
    color: #AAA;
  }
  
  .date-picker-grid-dates > .date {
    cursor: pointer;
    border-radius: .25rem;
    border: none;
    background: none;
  }
  
  .date-picker-grid-dates > *:hover {
    background-color: hsl(200, 100%, 80%);
    color: black;
  }
  
  .month-button {
    background: none;
    border: none;
    cursor: pointer;
  }
  
  .month-button:hover {
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    border-radius: .5rem;
  }