css-selectors.html

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  <title>2. CSS Selectors</title>
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    * {
      margin: 0;
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      box-sizing: border-box;
    }
    body, html {
      height: 100%;
      font-family: 'Poppins', sans-serif;
      overflow-x: hidden;
      background-color: #1cc9be;
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    .section {
      background-color: rgba(255, 255, 255, 0.3);
      margin: 20px auto;
      padding: 20px;
      border-radius: 12px;
      width: 90%;
      max-width: 1000px;
      box-shadow: 0 8px 16px rgba(0,0,0,0.3);
    }
    h2, h3 {
      color: #333;
      margin-bottom: 15px;
    }
    p {
      font-size: 18px;
      margin-bottom: 20px;
      line-height: 1.7;
    }
    textarea {
      width: 100%;
      height: 150px;
      font-family: monospace;
      font-size: 16px;
      padding: 10px;
      border: 2px solid white;
      border-radius: 8px;
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      margin-top: 15px;
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<body>

<div class="section">
  <h2>2. CSS Selectors</h2>

  <h3>1. Element Selector (Tag Selector)</h3>
  <p><strong>Explanation:</strong> Ye specific tag (jaise <code>h1</code>, <code>p</code>) ko target karta hai aur unke upar style lagata hai.</p>
  <textarea id="sel1">
<!DOCTYPE html>
<html>
<head>
  <style>
    h1 {
      color: blue;
    }
  </style>
</head>
<body>
  <h1>This is a heading</h1>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel1', 'out1')">Run Code</button>
  <iframe id="out1"></iframe>

  <h3>2. Class Selector (.)</h3>
  <p><strong>Explanation:</strong> Kisi bhi element me class attribute ke through styling lagayi ja sakti hai. Class ke liye <code>.</code> use hota hai.</p>
  <textarea id="sel2">
<!DOCTYPE html>
<html>
<head>
  <style>
    .highlight {
      background-color: yellow;
    }
  </style>
</head>
<body>
  <p class="highlight">This is highlighted text.</p>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel2', 'out2')">Run Code</button>
  <iframe id="out2"></iframe>

  <h3>3. ID Selector (#)</h3>
  <p><strong>Explanation:</strong> ID selector kisi specific element ko style karta hai jiska unique ID hota hai. Use karte hain <code>#</code>.</p>
  <textarea id="sel3">
<!DOCTYPE html>
<html>
<head>
  <style>
    #unique {
      color: red;
      font-weight: bold;
    }
  </style>
</head>
<body>
  <p id="unique">This is a unique paragraph.</p>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel3', 'out3')">Run Code</button>
  <iframe id="out3"></iframe>

  <h3>4. Universal Selector (*)</h3>
  <p><strong>Explanation:</strong> Sabhi elements ko ek sath target karne ke liye <code>*</code> use hota hai.</p>
  <textarea id="sel4">
<!DOCTYPE html>
<html>
<head>
  <style>
    * {
      font-family: Arial;
      color: darkgreen;
    }
  </style>
</head>
<body>
  <h1>Hello</h1>
  <p>Every element is styled</p>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel4', 'out4')">Run Code</button>
  <iframe id="out4"></iframe>

  <h3>5. Group Selector</h3>
  <p><strong>Explanation:</strong> Ek sath multiple selectors ko group me style karne ke liye comma use karte hain.</p>
  <textarea id="sel5">
<!DOCTYPE html>
<html>
<head>
  <style>
    h1, p {
      text-align: center;
      color: teal;
    }
  </style>
</head>
<body>
  <h1>This is Heading</h1>
  <p>This is Paragraph</p>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel5', 'out5')">Run Code</button>
  <iframe id="out5"></iframe>

  <h3>6. Attribute Selector</h3>
  <p><strong>Explanation:</strong> Jo elements kisi specific attribute (jaise type, href) ko hold karte hain unhe target karta hai.</p>
  <textarea id="sel6">
<!DOCTYPE html>
<html>
<head>
  <style>
    input[type="text"] {
      background-color: lightyellow;
    }
  </style>
</head>
<body>
  <input type="text" value="Text Field">
  <input type="submit" value="Submit">
</body>
</html>
  </textarea>
  <button onclick="runCode('sel6', 'out6')">Run Code</button>
  <iframe id="out6"></iframe>

  <h3>7. Pseudo-classes & Pseudo-elements</h3>
  <p><strong>Explanation:</strong> Ye special states ya parts of elements ko style karne ke liye hote hain. Jaise hover, first-line etc.</p>
  <textarea id="sel7">
<!DOCTYPE html>
<html>
<head>
  <style>
    a:hover {
      color: red;
    }
    p::first-line {
      font-weight: bold;
    }
  </style>
</head>
<body>
  <a href="#">Hover me</a>
  <p>This paragraph will show bold first line only.</p>
</body>
</html>
  </textarea>
  <button onclick="runCode('sel7', 'out7')">Run Code</button>
  <iframe id="out7"></iframe>
</div>

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