* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: "Inter", sans-serif;
    background-color: #ffffff;
    color: #000000;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
  
  .container {
    width: 96%;
    padding: 0 2%;
  }
  
  .main-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: #ffffff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
  }
  
  .nav-brand {
    position: relative;
    font-weight: 500;
    font-size: 1.5rem;
    color: #000000;
    text-decoration: none;
    display: inline-block;
  }
  
  .nav-brand span {
    transition: opacity 0.3s ease-in-out;
  }
  
  .nav-brand .brand-english {
    opacity: 0;
    position: absolute;
    top: 0;
    left: 0;
  }
  
  .nav-brand:hover .brand-korean {
    opacity: 0;
  }
  
  .nav-brand:hover .brand-english {
    opacity: 1;
  }
  
  .nav-links {
    display: flex;
    list-style: none;
    gap: 40px;
  }
  
  .nav-links a {
    text-decoration: none;
    color: #000000;
    font-size: 1.1rem;
    font-weight: 400;
    transition: opacity 0.3s ease;
  }
  
  .header-divider {
    border: none;
    height: 1px;
    background-color: #000000;
    margin: 0;
  }
  
  .error-page-content {
    text-align: center;
    padding: 100px 20px;
    position: relative;
  }
  
  .error-code {
    font-size: 12rem;
    font-weight: 500;
    color: #f2f2f2;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: -1;
    user-select: none;
    animation: glitch 7s infinite steps(1);
  }
  
  .error-title {
    font-size: 2.5rem;
    font-weight: 400;
    margin-bottom: 20px;
  }
  
  .error-description {
    font-size: 1.2rem;
    font-weight: 300;
    color: #555;
    max-width: 600px;
    margin: 0 auto 60px auto;
    line-height: 1.7;
  }
  
  .recommended-chapters {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    max-width: 900px;
    margin: 0 auto;
  }
  
  .chapter-link {
    text-decoration: none;
    color: #000;
    border: 1px solid #e0e0e0;
    padding: 25px;
    border-radius: 8px;
    transition: all 0.3s ease;
  }
  
  .chapter-link:hover {
    border-color: #000;
    transform: translateY(-5px);
    background-color: #f9f9f9;
  }
  
  .chapter-link h4 {
    font-size: 1.2rem;
    font-weight: 500;
    margin-bottom: 10px;
  }
  
  .chapter-link p {
    font-size: 1rem;
    font-weight: 300;
    color: #555;
    line-height: 1.5;
  }
  
  @keyframes glitch {
    0%,
    100% {
      text-shadow: none;
      opacity: 1;
    }
    25% {
      text-shadow: 2px 2px 0 #f0f0f0, -2px -2px 0 #efefef;
    }
    50% {
      opacity: 0.95;
    }
    75% {
      text-shadow: -2px 2px 0 #f1f1f1, 2px -2px 0 #f3f3f3;
    }
  }