fix project structure & static file

src/views/signup.ejs

@@ -6,8 +6,8 @@
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Signup</title>
-    <link rel="stylesheet" href="/css/style.css" <link rel="stylesheet" href="/css/style.css">
-    <link rel="stylesheet" href="../public/css/style.css">
+    <link rel="stylesheet" href="/static/css/style.css" <link rel="stylesheet" href="/css/style.css">
+    <link rel="stylesheet" href="/static/css/style.css">
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.7.2/css/all.min.css"
         integrity="sha512-Evv84Mr4kqVGRNSgIGL/F/aIDqQb7xQ2vcrdIwxfjThSH8CSR7PBEakCr51Ck+w+/U6swU2Im1vVX0SVk9ABhg=="
         crossorigin="anonymous" referrerpolicy="no-referrer" />