adding images

docs/get-started/connect.mdx

@@ -21,7 +21,14 @@ Linea is available by default in MetaMask through an Infura RPC endpoint.
         Find the network selector in the top-left of MetaMask, and click to see your available 
         networks. From here, select Linea Mainnet:
 
-        IMG
+        <div class="center-container">
+          <div class="img-small">
+            <img
+              src="/img/get_started/connect/MetaMask_change_network_to_Linea_extension.gif"
+              alt="MetaMask change network to Linea extension"
+            />
+          </div>
+        </div>
 
         If you don't see Linea Mainnet in the "Enabled networks" list, scroll to the "Additional
         networks" section, and click "Add". 
@@ -31,7 +38,14 @@ Linea is available by default in MetaMask through an Infura RPC endpoint.
         In the networks menu, scroll until you see the "Show test networks" toggle. If it's off,
         switch it on; you should see Linea Sepolia in the list. Select it to get started.
 
-        IMG
+        <div class="center-container">
+          <div class="img-small">
+            <img
+              src="/img/get_started/connect/MetaMask_show_test_network_Linea_Sepolia_extension.png"
+              alt="MetaMask change network to Linea Sepolia extension"
+            />
+          </div>
+        </div>
 
     </TabItem>
     <TabItem value="mobile" label="MetaMask Mobile">
@@ -42,14 +56,28 @@ Linea is available by default in MetaMask through an Infura RPC endpoint.
         Select "Linea Mainnet" to switch to it. If you don't see it in the list, scroll "Additional
         networks" list and tap "Add" to add Linea Mainnet to your wallet.
 
-        IMG
+        <div class="center-container">
+          <div class="img-small">
+            <img
+              src="/img/get_started/connect/MetaMask_change_network_to_Linea_mobile.gif"
+              alt="MetaMask change network to Linea mobile"
+            />
+          </div>
+        </div>
 
         **Linea Sepolia**
 
         Scroll until you see the "Show test networks" toggle. If it's off, switch it on; you should
         see Linea Sepolia in the list. Select it to get started.
 
-        IMG
+        <div class="center-container">
+          <div class="img-small">
+            <img
+              src="/img/get_started/connect/MetaMask_show_test_network_Linea_Sepolia_mobile.png"
+              alt="MetaMask change network to Linea Sepolia mobile"
+            />
+          </div>
+        </div>
 
     </TabItem>
 </Tabs>