<div class="input-container">
  <input type="text" placeholder="Add Item">
  <button class="button">Add</button>
</div>

<style>
/* From Uiverse.io by Smit-Prajapati - Tags: input, input effect , cool input */
.input-container {
  display: flex;
  background: white;
  border-radius: 1rem;
  background: linear-gradient(135deg, #23272F 0%, #14161a 100%);
  box-shadow: 10px 10px 20px #0e1013, -10px -10px 40px #383e4b;
  padding: 0.3rem;
  gap: 0.3rem;
}

.input-container input {
  border-radius: 0.8rem 0 0 0.8