html, body {
  margin: 0;
  padding: 0;
  background: #0a0a0a;
  font-family: 'Helvetica', sans-serif;
  color: #eaeaea;
  scroll-behavior: smooth;
  min-height: 100vh;
  font-size: 1rem;
  position: relative;
  overflow-x: hidden;
}

/* Modern Simple Gradient Background */
html::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: linear-gradient(135deg, 
    rgba(120, 80, 200, 0.08) 0%, 
    rgba(100, 120, 180, 0.06) 30%, 
    rgba(80, 160, 200, 0.05) 70%, 
    transparent 100%
  );
  z-index: -2;
  pointer-events: none;
}

html::after {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: linear-gradient(45deg, 
    transparent 0%, 
    rgba(255, 255, 255, 0.015) 50%, 
    transparent 100%
  );
  z-index: -1;
  pointer-events: none;
}

body > * {
  position: relative;
  z-index: 1;
}

@keyframes overlayShift {
  0%, 100% {
    background: linear-gradient(135deg, 
      rgba(255, 255, 255, 0.03) 0%, 
      transparent 50%, 
      rgba(255, 255, 255, 0.015) 100%);
  }
  50% {
    background: linear-gradient(225deg, 
      rgba(255, 255, 255, 0.025) 0%, 
      transparent 60%, 
      rgba(255, 255, 255, 0.02) 100%);
  }
}



body > * {
  position: relative;
  z-index: 1;
}
  
  .section {
    display: none;
    background: rgba(30, 32, 34, 0.6);
    border-radius: 20px;
    box-shadow: 0 8px 32px 0 rgba(0,0,0,0.2);
    padding: 2.5rem 2.5rem;
    margin-bottom: 2.5rem;
    border: 1px solid rgba(255,255,255,0.08);
    backdrop-filter: blur(15px);
    transition: box-shadow 0.3s ease;
  }

  .section:hover {
    box-shadow: 0 12px 36px 0 rgba(0,0,0,0.25);
  }

  .active {
    display: block;
    animation: fadeIn 0.5s;
  }

  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
  }

  .highlight {
    background: rgba(40,40,40,0.7);
    color: #fff !important;
    border-radius: 8px;
    box-shadow: 0 2px 8px 0 rgba(34,34,34,0.10);
    border: 1px solid rgba(80,80,80,0.18);
    font-family: inherit;
    padding: 10px;
    transition: background 0.2s, color 0.2s;
  }

  body {
    max-width: 960px;
    margin: 0 auto;
    line-height: 1.7;
    background: rgba(18, 20, 22, 0.5);
    position: relative;
    z-index: 1;
    backdrop-filter: blur(2px);
  }
  
  header {
    background: rgba(24, 26, 27, 0.7);
    border-bottom: 1px solid rgba(255,255,255,0.08);
    padding: 2.5rem 1rem 1.5rem 1rem;
    text-align: center;
    box-shadow: 0 4px 20px 0 rgba(0,0,0,0.15);
    backdrop-filter: blur(15px);
  }

  .header-content {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 2.5rem;
    margin-bottom: 2rem;
    padding-left: 1rem;
  }

  .header-text {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    text-align: left;
  }
  
  header h1 {
    margin: 0;
    font-size: 2.2rem;
    letter-spacing: 0.08rem;
    font-weight: 900;
    line-height: 1.2;
    color: #eaeaea;
    font-family: 'Helvetica', sans-serif;
    text-shadow: none;
    background: none;
    transition: none;
  }

  .subtitle {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 400;
    color: #c0c0c0;
    font-style: italic;
    line-height: 1.3;
    letter-spacing: 0.02rem;
  }

  .logo {
    max-width: 180px;
    height: auto;
    border-radius: 16px;
    box-shadow: 0 2px 16px 0 rgba(0,0,0,0.10);
    display: block;
    background: rgba(30,32,34,0.7);
    border: 1.5px solid rgba(80,80,80,0.18);
    flex-shrink: 0;
  }

  nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 2.5rem;
    padding: 0px;
    margin: 2rem 0 0 0;
  }

  nav ul li a {
    position: relative;
    text-decoration: none;
    font-weight: 600;
    color: #eaeaea;
    padding: 10px 0;
    font-size: 1.08rem;
    letter-spacing: 0.02em;
    background: transparent;
    border: none;
    outline: none;
    cursor: pointer;
    box-shadow: none;
    font-family: inherit;
    transition: color 0.2s;
    overflow: hidden;
  }

  nav ul li a::after {
    content: "";
    display: block;
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, rgba(255,255,255,0.0) 0%, #eaeaea 100%);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.35s cubic-bezier(.4,0,.2,1);
  }

  nav ul li a:hover::after, nav ul li a:focus::after {
    transform: scaleX(1);
  }

  nav ul li a:hover, nav ul li a:focus {
    color: #fff;
  }
  
  main {
    padding: 2.5rem 1.5rem 2.5rem;
    background: transparent;
  }
  
  section {
    margin-bottom: 2rem;
  }

  section h2 {
    margin-bottom: 1.2rem;
    font-size: 1.7rem;
    font-weight: 600;
    border-left: 4px solid rgba(255,255,255,0.12);
    padding-left: 0.7rem;
    color: #eaeaea;
    letter-spacing: 0.01em;
    font-family: inherit;
    text-shadow: 0 2px 8px rgba(0,0,0,0.10);
  }
  
  section p,
  section ul {
    margin: 0.5rem 0;
    color: #eaeaea;
    font-family: inherit;
  }
  
  section ul {
    list-style: disc;
    margin-left: 1.5rem;
  }
  
  footer {
    text-align: center;
    padding: 2rem 1rem 1.5rem 1rem;
    background: rgba(24, 26, 27, 0.7);
    border-top: 1px solid rgba(255,255,255,0.08);
    font-size: 1rem;
    margin-top: 2.5rem;
    color: #bdbdbd;
    box-shadow: 0 -4px 20px 0 rgba(0,0,0,0.15);
    font-family: inherit;
    backdrop-filter: blur(15px);
  }

  .img-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 28px;
    flex-wrap: wrap;
    margin: 1.5rem 0;
  }

  .img {
    max-width: 80%;
    height: auto;
    display: block;
    border-radius: 12px;
    box-shadow: 0 2px 16px 0 rgba(0,0,0,0.10);
    background: rgba(30,32,34,0.7);
    padding: 0.5rem;
    border: 1.5px solid rgba(80,80,80,0.18);
  }
/* Hyperlink styles */
a {
  color: #e8a574;
  text-decoration: none;
  transition: color 0.2s;
  font-weight: 600;
  position: relative;
}

a::after {
  content: "";
  display: block;
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, rgba(255,255,255,0.0) 0%, #f4b584 100%);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s cubic-bezier(.4,0,.2,1);
}

a:hover::after, a:focus::after {
  transform: scaleX(1);
}

a:hover, a:focus {
  color: #f4b584;
}

/* Code block styles: modern, dark, readable */
pre, code, pre code {
  font-family: inherit;
  background: rgba(30,32,34,0.92);
  color: #eaeaea;
  border-radius: 6px;
  padding: 0.5em 0.8em;
  font-size: 0.98em;
  line-height: 1.6;
  border: 1px solid rgba(80,80,80,0.18);
}

pre {
  overflow-x: auto;
  margin: 1.2em 0;
}

code {
  padding: 2px 6px;
  background: rgba(30,32,34,0.7);
  color: #b6e3a1;
  border-radius: 4px;
  font-size: 0.98em;
}

/* Playground button and GIF styles */
.playground-button-container {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin: 1rem 0;
}

.playground-gif {
  width: 60px;
  height: 60px;
  border-radius: 8px;
  box-shadow: 0 2px 12px 0 rgba(0,0,0,0.15);
  background: rgba(30,32,34,0.7);
  border: 1px solid rgba(80,80,80,0.18);
  flex-shrink: 0;
}

.playground-button {
  display: inline-block;
  padding: 12px 24px;
  background: rgba(60, 62, 64, 0.8);
  color: #eaeaea !important;
  text-decoration: none;
  border-radius: 8px;
  font-weight: 600;
  font-size: 1.1rem;
  border: 1px solid rgba(80,80,80,0.3);
  transition: all 0.3s ease;
  position: relative;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 16px 0 rgba(0,0,0,0.1);
  overflow: hidden;
}

.playground-button::after {
  content: "";
  display: block;
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, rgba(255,165,0,0) 0%, #ff8c00 100%);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s cubic-bezier(.4,0,.2,1);
}

.playground-button:hover {
  background: rgba(70, 72, 74, 0.9);
  color: #ff8c00 !important;
  border-color: rgba(255,140,0,0.4);
  box-shadow: 0 6px 20px 0 rgba(0,0,0,0.2);
  transform: translateY(-1px);
}

.playground-button:hover::after {
  transform: scaleX(1);
}

  @media (max-width: 600px) {
    body {
      max-width: 100%;
      line-height: 1.4;
    }

    .header-content {
      flex-direction: column;
      gap: 1rem;
      justify-content: center;
      padding-left: 0;
    }

    .logo {
      max-width: 140px;
    }

    header h1 {
      font-size: 1.5rem;
    }

    .subtitle {
      font-size: 0.95rem;
    }

    nav ul {
      flex-direction: column;
      gap: 1rem;
    }

    nav ul li a {
      padding: 8px 0;
      font-size: 1rem;
    }

    section h2 {
      font-size: 1.25rem;
    }

    .section {
      padding: 1.2rem 0.7rem;
    }

    footer {
      font-size: 0.8rem;
    }

    .img-container {
      flex-direction: column;
      gap: 10px;
    }

    .img {
      max-width: 95%;
      margin: 0 auto;
    }

    .playground-button-container {
      flex-direction: column;
      gap: 1rem;
      align-items: center;
    }

    .playground-gif {
      width: 50px;
      height: 50px;
    }

    .playground-button {
      padding: 10px 20px;
      font-size: 1rem;
    }
  }