/* General Reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  /* Body and Font Styling */
  body {
    font-family: 'Arial', sans-serif;
    background-color: #f9f9f9;
    color: #333;
    line-height: 1.6;
  }
  
  /* Header Styles */
  header {
    background-color: #333;
    color: #fff;
    padding: 20px 0;
  }
  
  header .container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
  }
  
  header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
  }
  
  header nav ul {
    list-style-type: none;
  }
  
  header nav ul li {
    display: inline;
    margin: 0 15px;
  }
  
  header nav ul li a {
    color: #fff;
    text-decoration: none;
    font-weight: bold;
  }
  
  header nav ul li a:hover {
    color: #f39c12;
  }
  
  /* Projects Section Styling */
  .projects-section {
    padding: 60px 0;
    background-color: #fff;
  }
  
  .projects-section .container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
  }
  
  .projects-section h2 {
    text-align: center;
    margin-bottom: 30px;
  }
  
  .filter-buttons {
    text-align: center;
    margin-bottom: 20px;
  }
  
  .filter-button {
    background-color: #333;
    color: #fff;
    border: none;
    padding: 10px 15px;
    margin: 0 5px;
    cursor: pointer;
  }
  
  .filter-button:hover {
    background-color: #f39c12;
  }
  
  .project-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
  }
  
  .project {
    background-color: #f3f3f3;
    padding: 20px;
    border-radius: 5px;
    text-align: center;
    transition: transform 0.2s;
  }
  
  .project:hover {
    transform: translateY(-5px);
  }
  
  .project img {
    width: 100%;
    height: auto;
    border-radius: 5px;
  }
  
  .project h3 {
    margin: 15px 0;
    font-size: 1.5rem;
  }
  
  .project p {
    font-size: 1rem;
  }
  
  /* Footer Styling */
  footer {
    background-color: #333;
    color: #fff;
    text-align: center;
    padding: 20px 0;
  }
  
  footer p {
    font-size: 1rem;
  }
.item {
  display: block;
}

.hidden {
  display: none;
}

  <link rel="javascript" href="index.js">