我正在使用Bootstrap 4在站点上工作，并且展示柜中的按钮没有得到我要赋予的颜色。
HTML
<!doctype html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- our css -->
<link rel="stylesheet" href="./app.css">
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css"
integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.0.13/css/all.css"
integrity="sha384-DNOHZ68U8hZfKXOrtjWvjxusGo9WQnrNx2sqG0tfsghAvtVlRW3tvkXWZh58N9jp" crossorigin="anonymous">
<link href="https://fonts.googleapis.com/css?family=Raleway:100,300,500,700" rel="stylesheet">
<link href="https://fonts.googleapis.com/css?family=Questrial" rel="stylesheet">
<title>Aurora Grove</title>
</head>
<body>
<section id="showcase">
<div class="header container text-white d-flex d-flex align-items-center flex-column py-4 border hight-showcase justify-content-center">
<button class="btn btn-primary btn-lg text-white ">book me </button>
</div>
</section>
</body>
</html>
CSS
btn-primary {
background: coral;
}
提供更具体的类或使用！important。
.btn-primary.btn-lg.text-white {
background-color: coral;
}<!doctype html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- our css -->
<link rel="stylesheet" href="./app.css">
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.0.13/css/all.css" integrity="sha384-DNOHZ68U8hZfKXOrtjWvjxusGo9WQnrNx2sqG0tfsghAvtVlRW3tvkXWZh58N9jp" crossorigin="anonymous">
<link href="https://fonts.googleapis.com/css?family=Raleway:100,300,500,700" rel="stylesheet">
<link href="https://fonts.googleapis.com/css?family=Questrial" rel="stylesheet">
<title>Aurora Grove</title>
</head>
<body>
<section id="showcase">
<div class="header container text-white d-flex d-flex align-items-center flex-column py-4 border hight-showcase justify-content-center">
<button class="btn btn-primary btn-lg text-white ">book me </button>
</div>
</section>
</body>请在下面尝试：
<!doctype html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- our css -->
<link rel="stylesheet" href="./app.css">
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css"
integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.0.13/css/all.css"
integrity="sha384-DNOHZ68U8hZfKXOrtjWvjxusGo9WQnrNx2sqG0tfsghAvtVlRW3tvkXWZh58N9jp" crossorigin="anonymous">
<link href="https://fonts.googleapis.com/css?family=Raleway:100,300,500,700" rel="stylesheet">
<link href="https://fonts.googleapis.com/css?family=Questrial" rel="stylesheet">
<title>Aurora Grove</title>
</head>
<body>
<section id="showcase">
<div class="header container text-white d-flex d-flex align-items-center flex-column py-4 border hight-showcase justify-content-center">
<button class="btn btn-primary btn-lg text-white ">book me </button>
</div>
</section>
</body>
.btn-primary{
background: coral !important;
}