A few modification

footer.html

@@ -1,4 +1,10 @@
 <footer id="footer">
-    <div id="src">My ass</div>
-    <div id="Contact"> Me Me Me</div>
+    <div id="src">
+        <a href="google.com">Une source</a>
+    </div>
+    <div id="Contact">
+        Front end : Bousquet Sébastien
+        --- Back end : Thorel Benjamin
+        --- Base de donné : JeConnaisPasSonNomDeFamille Jordan
+    </div>
 </footer>

header.html

@@ -1,7 +1,11 @@
 <header id="header">
-    <div id="logo"> Un Logo </div>
+    <div id="logo">
+        <a href="index.php">
+            <img src="Logo.jpg" class="logo">
+        </a>
+    </div>
     <nav id="nav">
-        <a id="google" href="google.com">Google</a>
-        <a id="unTest" href="bing.com">Bing</a>
+        <a id="google" class="nav-element" href="google.com">Google</a>
+        <a id="unTest" class="nav-element" href="bing.com">Bing</a>
     </nav>
 </header>

main.css

@@ -18,17 +18,32 @@ html, body{
 #header {
     display: flex;
     flex-direction: row;
-    padding: 30px;
+    padding: 3px;
     background-color: blanchedalmond;
 }
 
 #logo {
+    flex:1;
+    background-color: aqua;
     background-image: url("Logo.jpg");
-    background:no-repeat;
+    /*background:no-repeat;*/
+}
+
+.logo{
+    height: 100%;
+    width: 100%;
 }
 
 #nav {
     background-color: yellow;
+    flex: 9;
+    text-align: initial;
+    letter-spacing: 2px;
+    padding: 10px;
+}
+
+.nav-element {
+    padding: 10px;
 }
 
 /*Body et son contenu */
@@ -63,6 +78,7 @@ body {
     height: 100%;
     border: 1px solid rgba(0,0,0,.125);
     border-radius: .25rem;
+    overflow: scroll;
 }
 
 /*Footer et son contenue*/