
코딩 수정하느라 이전 문의글 지웠습니다.
답변 준비하고 계셨다면 죄송해요.

작성한 코드 및 에러 메세지
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css" rel="stylesheet"
integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js"
integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM"
crossorigin="anonymous"></script>
<title>스파르타코딩클럽 | 부트스트랩 연습하기</title>
<style>
.mytitle {
color: white;
height: 250px;
background-image: linear-gradient(0deg, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url("https://cdn.pixabay.com/photo/2021/02/02/02/34/cafe-5972490_960_720.jpg");
background-position: center;
background-size: cover;
display: flex;
flex-direction: column;
justify-content: center;
align-items: center;
}
.mypost {
background-color: lavenderblush;
max-width: 500px;
width: 95%;
margin: 50px auto 0px auto;
box-shadow: 0px 0px 3px 0px darkgray;
padding: 20px;
}
.mybtn {
justify-content: center;
align-items: center;
margin: auto;
border-radius: 50px;
}
.H-wrap {
max-width: 1200px;
width: 95%;
}
.card {
width: 95%;
max-width: 500px;
margin: 72px auto 0px auto;
background-color: white;
padding: 20px;
}
.cards > card-body {
margin-top: 10px;
margin-bottom: 10px;
}
</style>
</head>
<body>
<div class="mytitle">
<h1>Book, Cafe 방명록</h1>
</div>
<div class="mypost">
<div class="form-floating mb-3">
<input type="email" class="form-control" id="floatingInput" placeholder="name@example.com">
<label for="floatingInput">닉네임</label>
</div>
<div class="write-comment">
<textarea class="form-control" placeholder="응원댓글 같은 후기 부탁드려요~" id="floatingTextarea2" style="height: 100px"></textarea>
<label for="floatingTextarea2"></label>
</div>
<div class="mybtn">
<button type="button" class="btn btn-dark">방명록 남기기</button>
</div>
</div>
<div class="H-wrap">
<div class="row row-cols-1 row-cols-md-2 g-5">
<div class="card">
<div class="card-body">
<blockquote class="blockquote mb-0">
<p>책이 생각보다 은근 많아요</p>
<footer class="blockquote-footer">커피 마시러 왔다가 독서한 1인</footer>
</blockquote>
</div>
</div>
<div class="card">
<div class="card-body">
<blockquote class="blockquote mb-0">
<p>커피 향이 좋네요. 원두 뭐 쓰세요?</p>
<footer class="blockquote-footer">영업비밀 궁금한 서울사람</footer>
</blockquote>
</div>
</div>
<div class="card">
<div class="card-body">
<blockquote class="blockquote mb-0">
<p>♬차 마시러 왔다가 책도 읽고 가지요~♪♩</p>
<footer class="blockquote-footer">책에 낚인 동네주민</footer>
</blockquote>
</div>
</div>
<div class="card">
<div class="card-body">
<blockquote class="blockquote mb-0">
<p>♬차 마시러 왔다가 책도 읽고 가지요~♪♩</p>
<footer class="blockquote-footer">책에 낚인 동네주민</footer>
</blockquote>
</div>
</div>
<div class="card">
<div class="card-body">
<blockquote class="blockquote mb-0">
<p>♬차 마시러 왔다가 책도 읽고 가지요~♪♩</p>
<footer class="blockquote-footer">책에 낚인 동네주민</footer>
</blockquote>
</div>
</div>
</div>
</div>
</body>
</html>
