/* =========================================
   Workshop 3 – Advanced CSS
   ========================================= */

/* ---- Base page setup ---- */
:root {
    --brand: #4caf50;
    --ink: #222;
    --ink-soft: #444;
    --bg: #f7f9fb;
    --card: #ffffff;
    --border: #dcdfe4;
    --muted: #f2f4f7;
  }
  
  * { box-sizing: border-box; }
  
  body {
    margin: 24px;
    font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
    color: var(--ink);
    background: var(--bg);
  }
  
  h1, h2 { color: #0a2a6b; }
  h1 { text-align: center; margin-bottom: 8px; }
  p { color: var(--ink-soft); }
  
  hr { border: 0; border-top: 1px solid var(--border); margin: 24px 0; }
  
  /* =========================================
     TASK 1: CSS TRANSITIONS
     ========================================= */
  .transition-button {
    background-color: lightblue;     /* initial color */
    color: #083344;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s ease; /* smooth transition */
  }
  .transition-button:hover {
    background-color: lightcoral;    /* hover color */
  }
  
  /* =========================================
     TASK 2: CSS ANIMATIONS
     ========================================= */
  .animation-track {
    max-width: 240px;
    height: 70px;
    background: var(--muted);
    border: 1px dashed var(--border);
    border-radius: 8px;
    position: relative;
    padding: 8px;
  }
  
  .animation-box {
    width: 50px;
    height: 50px;
    background-color: lightgreen;
    position: relative;
    animation: move 2s infinite alternate; 
    border-radius: 6px;
  }
  
  /* keyframes: move between left: 0 and left: 100px */
  @keyframes move {
    from { left: 0; }
    to   { left: 100px; }
  }
  
  @media (prefers-reduced-motion: reduce) {
    .animation-box {
      animation: none;
    }
  }
  
  /* =========================================
     TASK 3: CSS PSEUDO-CLASSES
     ========================================= */
  .pseudo-list {
    list-style: none;
    padding: 0;
    margin: 0;
    max-width: 360px;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
  }
  .pseudo-list li {
    padding: 10px 14px;
  }
  .pseudo-list li:nth-child(odd)  { background-color: #f6f6f6; }
  .pseudo-list li:nth-child(even) { background-color: #ffffff; }
  
  /* =========================================
     TASK 4: CSS FILTERS
     ========================================= */
  .filter-image {
    display: block;
    filter: grayscale(100%);                 
    transition: filter 0.3s ease;            
    border-radius: 10px;
    box-shadow: 0 1px 3px rgba(0,0,0,.06);
  }
  .filter-image:hover {
    filter: grayscale(0%);                   
  }
  
  /* =========================================
     TASK 5: CSS PSEUDO-ELEMENTS
     ========================================= */
  .quote {
    position: relative;
    padding: 16px 16px 16px 36px;  
    font-style: italic;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 8px;
    max-width: 560px;
  }
  .quote::before {
    content: "“";        
    font-size: 40px;
    line-height: 1;
    position: absolute;
    left: 10px;
    top: 8px;
    color: #c7c7c7;
    font-family: Georgia, 'Times New Roman', serif;
  }
  
  .course-table {
    width: 100%;
    max-width: 720px;
    border-collapse: collapse;
    margin: 12px 0;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden; 
  }
  .course-table th, .course-table td {
    border-bottom: 1px solid var(--border);
    padding: 10px 12px;
    text-align: left;
  }
  .course-table th { background: #f2f4f7; }
  .course-table tr:last-child td { border-bottom: none; }
  
  .contact-form {
    display: grid;
    gap: 10px;
    width: 320px;
    margin: 16px 0;
    background: #eaf4ff;
    padding: 16px;
    border-radius: 8px;
    border: 1px solid var(--border);
  }
  .contact-form input[type="text"],
  .contact-form input[type="email"] {
    padding: 8px 10px;
    border: 1px solid #cdd3da;
    border-radius: 6px;
  }
  .contact-form input[type="submit"] {
    background: var(--brand);
    color: #fff;
    padding: 10px 14px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
  }
  .contact-form input[type="submit"]:hover {
    filter: brightness(0.95);
  }