User profile page setup

app/assets/stylesheets/main.css

@@ -56,6 +56,11 @@ nav {
   }
 }
 
+main {
+  max-width: 100em;
+  margin: 0 auto;
+}
+
 a:link, a:visited {
   color: var(--highlight-color);
 }

app/controllers/users_controller.rb

@@ -17,7 +17,7 @@ class UsersController < ApplicationController
   end
 
   def show
-    @user = User.find(params[:id])
+    @user = User.find_by(username: params[:id])
   end
 
   private

app/models/user.rb

@@ -17,4 +17,12 @@ class User < ApplicationRecord
             format: { with: /\A.*@.*\..*\z/ } # Only very basic regex
 
   validates :password, confirmation: true
+
+  def to_param
+    username
+  end
+
+  def full_name
+    "#{first_name} #{last_names}"
+  end
 end

app/views/users/show.html.erb

@@ -1 +1,3 @@
-<%= @user.username %>
+<h2><%= @user.username %></h2>
+<h4><%= @user.full_name %></h4>
+