views/layout.erb
<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title><%= @title %></title>
<meta content="<%= @title %>" name="apple-mobile-web-app-title">
<meta content="<%= @title %>" name="application-name">
<%= erb :'partial/seo' %>
<%= erb :'partial/cdn' %>
</head>
<body>
<%= erb :'partial/header' %>
<%= yield %>
<%= erb :'partial/footer' %>
</body>
</html>