:root {
      --bg-light: #f9f9fb;
      --bg-dark: #1e1e1e;
      --text-light: #333;
      --text-dark: #f1f1f1;
      --accent-blue-dark: #003399;
      --accent-blue: #3366ff;
      --accent-blue-light: #66ccff;
      --button-dark: #3366ff;
      --button-dark-hover: #003399;
      --button-light: #FFFFCC;
      --button-light-hover: #FFFF99;
      --section-dark: #444444;
      --section-light: #EEEEEE;
      --accent-yellow: #ffff88;
      --accent-yellow-light: #ffffcc;
      --accent-fuchsia: #ffaad9;
      --bg-menu-light: #66ccff;
      --bg-menu-dark: #003399;
      --hover-color: #FFFFFF;
      --shadow-light: rgba(0, 0, 0, 0.2);
      --shadow-dark: rgba(255, 255, 255, 0.15);
    }

    body {
      margin: 0;
      font-family: system-ui, sans-serif;
      background-color: var(--bg-light);
      color: var(--text-light);
      transition: background-color 0.3s, color 0.3s;
    }

    body.dark-mode {
      background-color: var(--bg-dark);
      color: var(--text-dark);
    }

    nav {
      display: flex;
      justify-content: space-between;
      align-items: center;
      background-color: var(--bg-menu-light);
      padding: 1rem;
      box-shadow: 0 4px 6px var(--shadow-light);
    }

    body.dark-mode nav {
        background-color: var(--bg-menu-dark);
        box-shadow: 0 4px 6px var(--shadow-dark);
    }

    nav .logo a {
      font-size: 1.2rem;
      font-weight: bold;
      color: var(--text-light); 
      text-decoration: none;
    }
    body.dark-mode nav .logo a {
      font-size: 1.2rem;
      font-weight: bold;
      color: var(--text-dark);
      text-decoration: none; 
    }    

    nav ul {
      list-style: none;
      display: flex;
      gap: 1rem;
      margin: 0;
      padding: 0;
      align-items: center;
    }

nav ul li a {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
    cursor: pointer;
    transition: color 0.3s;
    background: none;
    border: none;
    font-size: 1rem;
}

.theme-toggle {
    text-decoration: none;
    font-weight: 500;
    cursor: pointer;
    transition: color 0.3s;
    background: none;
    border: none;
    font-size: 1rem;
}




nav ul li a:hover {
    color: var(--hover-color);
}



body.dark-mode nav ul li a {
    color: var(--text-dark);
}

body.dark-mode nav ul li a:hover {
    color: var(--text-light);    
}

body.dark-mode #svgMoon {
    color: var(--text-dark);
    stroke: var(--text-dark);
}
    
body #svgSun {
    color: var(--text-light);
    stroke: var(--text-light);
    /* filter: brightness(0) invert(1); */
}  

@media (hover: hover) {
    body.dark-mode #svgMoon:hover {
        color: var(--text-light);
        stroke: var(--text-light);
        /* filter: brightness(0) invert(1); */
    }
    body #svgSun:hover {
        color: var(--text-dark);
        stroke: var(--text-dark);
    }
}
        

    .menu-toggle {
      display: none;
      flex-direction: column;
      cursor: pointer;
    }

    .menu-toggle span {
      height: 3px;
      width: 25px;
      background-color: var(--text-light);
      margin: 4px 0;
      color: var(--text-light); 
    }
    
    body.dark-mode .menu-toggle span {
      color: var(--text-dark); 
      background-color: var(--text-dark);
    }

    @media (max-width: 768px) {

    }

    #svgMoon, #svgSun {
      width: 20px;
      height: 20px;
      transition: filter 0.3s;
    }

    header {
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 2rem 1rem 1rem;
      text-align: center;
    }

    header img {
      width: 240px;
      height: 240px;
    }

    h1 {
      margin: 1rem 0 0.25rem;
      font-size: 2rem;
    }

    
    body.dark-mode p.slogan {
      font-size: 1rem;
      color: var(--accent-blue-light);
      margin: 0;
    }
    
    p.slogan {
      font-size: 1rem;
      color: var(--accent-blue);
      margin: 0;
    }

    footer {
      text-align: center;
      padding: 2rem 1rem;
      font-size: 0.9rem;
      opacity: 0.6;
    }
    
    
    
.category { color: var(--text-light); stroke: var(--text-light); text-decoration:none; }
.category:hover { color: var(--text-light); stroke: var(--text-light); }
body.dark-mode .category:hover { color: var(--text-dark); stroke: var(--text-dark);  }
body.dark-mode .category { color: var(--text-dark); stroke: var(--text-dark); text-decoration:none;  }
    
.category svg { color: inherit; stroke: inherit; }
.category svg:hover { color: inherit; stroke: inherit; }
body.dark-mode .category svg { color: var(--accent-yellow); stroke: var(--accent-yellow); }
body.dark-mode .category svg:hover { color: var(--accent-yellow-light); stroke: var(--accent-yellow-light); }

.category2 { color: var(--text-light); fill: var(--text-light); stroke: var(--text-light); text-decoration:none; }
.category2:hover { color: var(--text-light); fill: var(--text-light); stroke: var(--text-light); }
body.dark-mode .category2:hover { color: var(--text-dark); fill: var(--text-dark); stroke: var(--text-dark); }     
body.dark-mode .category2 { color: var(--text-dark); fill: var(--text-dark); stroke: var(--text-dark); text-decoration:none; }        
    
.category2 svg { color: inherit; fill: inherit; stroke: inherit; }
.category2 svg:hover { color: inherit; fill: inherit; stroke: inherit; }
body.dark-mode .category2 svg { color: var(--accent-yellow); fill: var(--accent-yellow); stroke: var(--accent-yellow); }
body.dark-mode .category2 svg:hover { color: var(--accent-yellow-light); fill: var(--accent-yellow-light); stroke: var(--accent-yellow-light); }    
    
.category, .category2 {
    background: var(--accent-yellow-light);
}
.category:hover, .category2:hover {
    box-shadow: 0 6px 12px rgba(0,0,0,0.2);
    background: var(--accent-yellow);
}
body.dark-mode .category, body.dark-mode .category2 {
    background: var(--button-dark)
}
body.dark-mode .category:hover, body.dark-mode .category2:hover {
    box-shadow: 0 6px 12px rgba(0,0,0,0.2);
    background: var(--button-dark-hover)
}

body.dark-mode .unit-button 
{
    width: unset;    
    background: var(--button-dark)
}
body.dark-mode .unit-button:hover
{
    width: unset;
    background: var(--button-dark-hover)
}
body.dark-mode .unit-button.active
{
    width: unset;
    background: var(--button-dark-hover)
}

.unit-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}
    
.unit-button 
{
    width: unset;    
    background: var(--button-light)
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: bold;    
}
.unit-button:hover
{
    width: unset;
    background: var(--button-light-hover)
}
.unit-button.active
{
    width: unset;
    background: var(--button-light-hover)
}




@media (min-width: 1px) and (max-width: 767px) {
    .categories {
      padding: 2rem 1rem;
      text-align: center;
    }
    .category-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
      gap: 2rem;
      max-width: 700px;
      margin: 0 auto;
      transition: all 0.5s ease-in;
    }
    .category, .category2 {
      border-radius: 1rem;
      padding: 1rem;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      box-shadow: 0 2px 5px rgba(0,0,0,0.1);
      cursor: pointer;
    }
    .category:hover, .category2:hover {
      transform: translateY(-4px);
      
    }    
    body.dark-mode .category:hover, body.dark-mode .category2:hover {
      transform: translateY(-4px);
    }

    


    .category h2, .category2 h2 {
      margin: 0;
      font-size: 1.1rem;
    }


  .menu-toggle {
    display: flex;
  }    
    
    
    nav ul {
        display: none;
        background-color: var(--bg-menu-light);
        flex-direction: column;
        position: absolute;
        top: 60px;
        right: 0;
        width: 200px;
        padding: 2rem;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        list-style: none;
        gap: 2rem;
        margin: 0;
        align-items: center;
    }
    body.dark-mode nav ul {
        background-color: var(--bg-menu-dark);
    }
    nav ul.show {
        display: flex;
    }
    
    .converter-section {
        max-width: 700px;
        transition: all 0.5s ease-in;
    }        
}
@media (min-width: 768px) and (max-width: 1199px) {
    .categories {
      padding: 2rem 1rem;
      text-align: center;
    }
    .category-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
      gap: 2rem;
      max-width: 700px;
      margin: 0 auto;
      transition: all 0.5s ease-in;
    }
    .category, .category2 {
      background: var(--accent-yellow-light);
      border-radius: 1rem;
      padding: 1rem;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      box-shadow: 0 2px 5px rgba(0,0,0,0.1);
      cursor: pointer;
    }
    .category:hover, .category2:hover {
      transform: translateY(-4px);
      box-shadow: 0 6px 12px rgba(0,0,0,0.2);
      background: var(--accent-yellow);
    }


    .category h2, .category2 h2 {
      margin: 0;
      font-size: 1.1rem;
    }
    
    nav ul {
      list-style: none;
      display: flex;
      gap: 1rem;
      margin: 0;
      padding: 0;
      align-items: center;
    }
    
    .converter-section {
        max-width: 700px;
        transition: all 0.5s ease-in;
    }    
}
@media (min-width: 1200px) {
    .categories {
      padding: 2rem 1rem;
      text-align: center;
    }
    .category-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
      gap: 2rem;
      max-width: 960px;
      margin: 0 auto;
      transition: all 0.5s ease-in;
    }
    .category, .category2 {
      background: var(--accent-yellow-light);
      border-radius: 1rem;
      padding: 1rem;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      box-shadow: 0 2px 5px rgba(0,0,0,0.1);
      cursor: pointer;
    }
    .category:hover, .category2:hover {
      transform: translateY(-4px);
      box-shadow: 0 6px 12px rgba(0,0,0,0.2);
      background: var(--accent-yellow);
    }

    .category h2, .category2 h2 {
      margin: 0;
      font-size: 1.1rem;
    }
    
    nav ul {
      list-style: none;
      display: flex;
      gap: 1rem;
      margin: 0;
      padding: 0;
      align-items: center;
    }
    
    .converter-section {
        max-width: 960px;
        transition: all 0.5s ease-in;
    }
    
    
}

  .result {
    margin-top: 1.5rem;
    font-weight: bold;
    text-align: center;
    font-size: 1.2rem;
  }     
  
  
.converter-section-container 
{
    box-sizing: border-box;
    padding: 1rem;
}
  
.converter-section {
    margin: 2rem auto;
    background-color: var(--section-light);
    padding: 2rem;
    border-radius: 1rem;
    border: 1px solid #CCc;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    box-sizing: border-box;
}

body.dark-mode .converter-section {
    background-color: var(--section-dark);
    border: 1px solid #777;
    box-shadow: 0 2px 10px rgba(255,255,255,0.1);
}

    .converter-section h2 {
      margin-top: 0;
      font-size: 1.5rem;
      text-align: center;
    }

    .converter-section p {
      text-align: center;
      margin-bottom: 2rem;
      font-size: 1rem;
    }

    .converter-section label {
      display: block;
      margin-bottom: 0.5rem;
      font-weight: bold;
    }

    .converter-section input,
    .converter-section select {
      width: 100%;
      padding: 0.5rem;
      margin-bottom: 1rem;
      border: 1px solid #ccc;
      border-radius: 0.5rem;
      font-size: 1rem;
      box-sizing: border-box;
    }

    body.dark-mode .converter-section input,
    body.dark-mode .converter-section select {
      background-color: #333;
      border:1px solid #777;
      color: var(--text-dark);
    }
        
    .converter-section textarea {
      width: 100%;
      height: 120px;
      padding: 1rem;
      font-size: 1rem;
      border-radius: 0.5rem;
      border: 1px solid #ccc;
      margin-bottom: 1rem;
      resize: vertical;
      box-sizing: border-box;
    }
    
    body.dark-mode .converter-section textarea {
      background-color: #333;
      border:1px solid #777;
      color: var(--text-dark);
    }    

    .converter-section .button-group {
      display: flex;
      flex-wrap: wrap;
      gap: 0.5rem;
      margin-bottom: 1rem;
    }    
    
    .converter-section button {
      padding: 0.75rem;
      background-color: var(--button-light);
      color: var(--text-light);
      border: none;
      border-radius: 0.5rem;
      font-weight: bold;
      font-size: 1rem;
      cursor: pointer;
      box-shadow: 0 0 4px rgba(0,0,0,0.35);
    }

    .converter-section button:hover {
      background-color: var(--button-light-hover);
      color: var(--text-light);
      box-shadow: 0 0 6px rgba(0,0,0,0.45);
      text-decoration:underline;
    }
    
    body.dark-mode .converter-section button {
      background-color: var(--button-dark);
      color: var(--text-dark);
    }

    body.dark-mode .converter-section button:hover {
      background-color: var(--button-dark-hover);
      color: var(--text-dark);
    }
    
    .converter-section .button-group button {
      flex: 1 1 45%;
      padding: 0.75rem;
      border: none;
      border-radius: 0.5rem;
      font-weight: bold;
      font-size: 1rem;
      cursor: pointer;
      transition: background-color 0.3s;
    }
    
    body.dark-mode .converter-section .button-group button {
      flex: 1 1 45%;
      padding: 0.75rem;
      border: none;
      border-radius: 0.5rem;
      font-weight: bold;
      font-size: 1rem;
      cursor: pointer;
      transition: background-color 0.3s;
    }

    .converter-section .result {
      margin-top: 2.5rem;
      padding: 1rem;
      background-color: white;
      border:1px solid #777;
      border-radius: 0.5rem;
      text-align: center;
      font-size: 1.2rem;
    }

    body.dark-mode .converter-section .result {
      background-color: #333;
      border:1px solid var(--accent-yellow-light);
      color: var(--text-dark);
    }