Added images from the placeholder.svg folder

Author: ChinweP

Wireframe/index.html

@@ -15,7 +15,7 @@ <h1>Understanding README Files, Wireframes and Git Branches</h1>
     <main>
       <!--Top article (full-width)-->
       <article class="top-article" id="readme-article">
-        <img src="images/readme.png" alt="Illustration of a README file" />
+        <img src="placeholder.svg" alt="Illustration of a README file" />
         <h2>What is the purpose of a README file?</h2>
         <p>
           A README file explains what a project is about, how to use it, and any important information someone needs before working with the project code.
@@ -28,7 +28,7 @@ <h2>What is the purpose of a README file?</h2>
     <section class="bottom-articles">
 
       <article id="wireframe-article">
-        <img src="images/wireframe.png" alt="Example of a webpage wireframe"/>
+        <img src="placeholder.svg" alt="Example of a webpage wireframe"/>
         <h2>What is the purpose of a wireframe?</h2>
         <p>
           A wireframe is a simple layout plan that shows where content will go on a webpage before you start designing or coding.
@@ -38,7 +38,7 @@ <h2>What is the purpose of a wireframe?</h2>
       </article>
 
       <article id="branch-article">
-        <img src="images/git-branch.png" alt="Diagram showing Git branches"/>
+        <img src="placeholder.svg" alt="Diagram showing Git branches"/>
         <h2>What is a branch in Git?</h2>
         <p>
           A Git baranch lets developers work on new features without affecting the main project. When finished, the branch can be merged back in.

Wireframe/style.css

@@ -95,4 +95,18 @@ article {
   gap: var(--space);
 }
 
+header{
+  text-align: center;
+}
+
+footer {
+  position: fixed;
+  bottom: 0;
+  left: 0;
+  width: 100%;
+  text-align: center;
+}
+
+
+