Stylesheets cascade

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 <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        h1 {
            color: brown
        }
        h1 {
            color: blue;
        }
    </style>
</head>
<body>
    <h1>que color seria</h1>
</body>
</html>

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Untitled

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #azul { 
            color: blue;
        }
        .rojo {
            color: red;
        }
    </style>
</head>
<body>
    <div id="azul" class="rojo">que color seria</div>    
</body>
</html>

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