공백, >, +, ~ 등 결합자(combinator)를 이용해 특정 요소를 선택
<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
header span {
color: blue;
}
</style>
</head>
<body>
<header>
<h1>header -> h1</h1>
<span>header -> span</span>
<br>
<div>
<span>header -> div -> span</span>
</div>
</header>
<span>span</span>
</body>
</html>

기호를 이용해 선택자를 조합
<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
header > span {
color: blue;
}
</style>
</head>
<body>
<header>
<h1>header -> h1</h1>
<span>header -> span</span>
<br>
<div>
<span>header -> div -> span</span>
</div>
</header>
<span>span</span>
</body>
</html>

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
header + span {
color: blue;
}
</style>
</head>
<body>
<header>
<h1>header -> h1</h1>
<span>header -> span</span>
<br>
<div>
<span>header -> div -> span</span>
</div>
</header>
<span>span1</span>
<div>
<span>div -> span2</span>
</div>
<span>span3</span>
</body>
</html>

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
header ~ span {
color: blue;
}
</style>
</head>
<body>
<header>
<h1>header -> h1</h1>
<span>header -> span</span>
<br>
<div>
<span>header -> div -> span</span>
</div>
</header>
<span>span1</span>
<div>
<span>div -> span2</span>
</div>
<span>span3</span>
</body>
</html>

HTML 요소의 속성을 이용하여 특정 요소를 선택
<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
[target] {
color: green;
}
</style>
</head>
<body>
<a href="" target="_blank">네이버</a>
<br>
<a href="">구글</a>
</body>
</html>
target 속성을 가진 요소만 적용

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
[target="_self"] {
color: green;
}
</style>
</head>
<body>
<a href="" target="_blank">네이버</a>
<br>
<a href="" target="_self">구글</a>
</body>
</html>
target="_self" 인 요소만 적용

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
[class~=att_class] {
color: green;
}
</style>
</head>
<body>
<h3 class="att_class">att_class</h3>
<h3 class="att">att</h3>
<h3 class="att_class2 att_class">att_class2 att_class</h3>
<h3 class="att-1">att-1</h3>
</body>
</html>
class 속성의 값이 att_class가 포함된 요소만 적용

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
[class~=att_class] {
color: green;
}
</style>
</head>
<body>
<h3 class="att_class">att_class</h3>
<h3 class="att">att</h3>
<h3 class="att_class2 att_class">att_class2 att_class</h3>
<h3 class="att-1">att-1</h3>
</body>
</html>
class 속성의 값이 att 또는 att- 인 요소만 적용
