CSS Attribute Selectors

Attribute selectors in CSS let you target elements by the presence or value of their attributes, like type, href, target, lang, etc.

This makes your CSS smarter and more dynamic — no need for extra classes!

✅ Basic Syntax

selector[attribute] {
  /* styles */
}

📌 Common Attribute Selector Types

🎯 Examples

1. Existence Only

input[required] {
  border: 1px solid red;
}

Matches any <input> with the required attribute.

2. Exact Match

input[type="email"] {
  background-color: #f0f8ff;
}

Only targets <input type="email">.

3. Space-separated List

div[class~="highlight"] {
  background: yellow;
}

Matches: <div class="note highlight warning"> ✅
Not: <div class="highlighted"> ❌

4. Hyphen-separated Prefix

p[lang|="en"] {
  font-style: italic;
}

Matches: lang="en", lang="en-US", etc.

5. Starts With

a[href^="https://"] {
  color: green;
}

Targets all secure links.

6. Ends With

img[src$=".png"] {
  border: 1px solid #ccc;
}

Selects only PNG images.

7. Contains Value

a[href*="login"] {
  font-weight: bold;
}

Targets links like href="/user/login".

🔐 Real Use Cases

• Styling external links
• Targeting form fields by type
• Image format–based styling
• Language-based formatting

⚠️ Best Practices

• Attribute selectors are powerful, but avoid overuse on large DOMs — can affect performance.
• Prefer exact or starts-with match for performance.
• Combine with class or tag selectors when possible for specificity.

input[type="checkbox"]:checked {
  /* safe and fast */
}