diff --git a/week-1/1-parent-child/index.html b/week-1/1-parent-child/index.html
index 458a4cb21..3c8abf1bc 100644
--- a/week-1/1-parent-child/index.html
+++ b/week-1/1-parent-child/index.html
@@ -27,6 +27,7 @@
           <p class="message__content">
             I can meet on Tuesday and Wednesday after 4.
           </p>
+          <span class="message__time">7:15pm</span>
         </div>
       </div>
     </div>
diff --git a/week-1/2-html-attributes/index.html b/week-1/2-html-attributes/index.html
index dc861fa4f..3574ef47c 100644
--- a/week-1/2-html-attributes/index.html
+++ b/week-1/2-html-attributes/index.html
@@ -23,14 +23,14 @@
         <div class="message">
           <div class="message__author">Luke</div>
           <p class="message__content">
-            Let's meet at the iCafe in Merchant City. https://goo.gl/maps/aza4h9nUBhn
+            Let's meet at the <a href="https://goo.gl/maps/aza4h9nUBhn">iCafe in Merchant Cityn</a>
           </p>
           <span class="message__time">7:35pm</span>
         </div>
         <div class="message">
           <div class="message__author">Won</div>
           <p class="message__content">
-            Ok! https://media.giphy.com/media/l41K4KlVE8dgozf8I/giphy.gif
+            Ok! <img src="https://media.giphy.com/media/l41K4KlVE8dgozf8I/giphy.gif" />
           </p>
           <span class="message__time">7:38pm</span>
         </div>
diff --git a/week-1/3-semantic-html/index.html b/week-1/3-semantic-html/index.html
index 3640deaff..e41e5620c 100644
--- a/week-1/3-semantic-html/index.html
+++ b/week-1/3-semantic-html/index.html
@@ -12,30 +12,36 @@
 
   <body>
     <div class="site-wrapper">
-      <div class="site-header">
+      <header role="banner" class="site-header">
         <div class="site-header__title">Messages</div>
-      </div>
-      <div class="messages">
-        <div class="message">
+      </header>
+      <main role="main" class="messages">
+        <article class="message">
           <div class="message__author">Won</div>
           <p class="message__content">Where should we meet later?</p>
-          <span class="message__time">Mar 25, 2018 7:25pm</span>
-        </div>
-        <div class="message">
+          <span class="message__time"
+            ><time datetime="2018-03-25T19:25">Mar 25, 2018 7:25pm</time></span
+          >
+        </article>
+        <article class="message">
           <div class="message__author">Luke</div>
           <p class="message__content">
             Let's meet at the iCafe in Merchant City. https://goo.gl/maps/aza4h9nUBhn
           </p>
-          <span class="message__time">Mar 25, 2018 7:35pm</span>
-        </div>
-        <div class="message">
+          <span class="message__time"
+            ><time datetime="2018-03-25T19:35">Mar 25, 2018 7:35pm</time></span
+          >
+        </article>
+        <article class="message">
           <div class="message__author">Won</div>
           <p class="message__content">
             Ok! https://media.giphy.com/media/l41K4KlVE8dgozf8I/giphy.gif
           </p>
-          <span class="message__time">Mar 25, 2018 7:38pm</span>
-        </div>
-      </div>
+          <span class="message__time"
+            ><time datetime="2018-03-25T19:38">Mar 25, 2018 7:38pm</time></span
+          >
+        </article>
+      </main>
       <div id="result" class="result"></div>
     </div>
     <script defer src="/js/3-result.js"></script>
diff --git a/week-1/4-links-scripts/index.html b/week-1/4-links-scripts/index.html
index 303c7fbd2..57a20ea2a 100644
--- a/week-1/4-links-scripts/index.html
+++ b/week-1/4-links-scripts/index.html
@@ -1,6 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
   <head>
+    <link rel="stylesheet" href="css/missing-styles.css" />
     <meta charset="utf-8" />
     <title>4. Adding Links and Scripts - HTML, CSS and Git Exercises</title>
     <meta name="viewport" content="width=device-width, initial-scale=1" />
@@ -33,5 +34,6 @@
         </div>
       </div>
     </div>
+    <script src="js/convertUrls.js"></script>
   </body>
 </html>
diff --git a/week-1/5-css-selectors/message-backgrounds.css b/week-1/5-css-selectors/message-backgrounds.css
index ffe483325..d93d996a4 100644
--- a/week-1/5-css-selectors/message-backgrounds.css
+++ b/week-1/5-css-selectors/message-backgrounds.css
@@ -1 +1,10 @@
 /* Add your CSS code below */
+#first-message .message__content {
+  background-color: red;
+}
+article .message__content {
+  background-color: cadetblue;
+}
+.message--latest .message__content {
+  background-color: yellow;
+}
diff --git a/week-1/6-css-properties/styles.css b/week-1/6-css-properties/styles.css
index ffe483325..b207edd82 100644
--- a/week-1/6-css-properties/styles.css
+++ b/week-1/6-css-properties/styles.css
@@ -1 +1,24 @@
 /* Add your CSS code below */
+
+a {
+  color: red;
+  font-weight: bold;
+  text-decoration: none;
+}
+
+.message__time {
+  font-size: 0.9rem;
+}
+
+.message--unread .message__content {
+  border-left-style: solid;
+  border-left-width: 5px;
+  border-left-color: blue;
+}
+
+.message--old .message__content {
+  opacity: 0.5;
+}
+.message__content {
+  line-height: 50px;
+}
diff --git a/week-1/7-css-box/styles.css b/week-1/7-css-box/styles.css
index 013b94f1e..8aac92c10 100644
--- a/week-1/7-css-box/styles.css
+++ b/week-1/7-css-box/styles.css
@@ -4,3 +4,9 @@
   border-radius: 4px;
   background: #fff;
 }
+.country {
+  padding: 5px;
+}
+* {
+  border: 1px solid red;
+}
diff --git a/week-1/8-advanced-selectors/styles.css b/week-1/8-advanced-selectors/styles.css
index d35c3c371..ebc0d34ef 100644
--- a/week-1/8-advanced-selectors/styles.css
+++ b/week-1/8-advanced-selectors/styles.css
@@ -1 +1,13 @@
 /* Try different box model properties below */
+.site-header > p {
+  color: white;
+  margin-bottom: unset;
+}
+
+.site-footer > p {
+  font-size: 12px;
+  text-align: center;
+}
+.message:last-child {
+  box-shadow: 4px 4px 0 #dba944;
+}
diff --git a/week-2/10-media-queries/columns.css b/week-2/10-media-queries/columns.css
index 43e80d23c..3e8625825 100644
--- a/week-2/10-media-queries/columns.css
+++ b/week-2/10-media-queries/columns.css
@@ -1 +1,11 @@
 /* Add your own CSS code below */
+@media screen and (min-width: 768px) {
+  .countries {
+    columns: 2;
+  }
+}
+@media screen and (min-width: 1200px) {
+  .countries {
+    columns: 3;
+  }
+}
diff --git a/week-2/11-flexbox/flexbox.css b/week-2/11-flexbox/flexbox.css
index 43e80d23c..af6d6cb2d 100644
--- a/week-2/11-flexbox/flexbox.css
+++ b/week-2/11-flexbox/flexbox.css
@@ -1 +1,5 @@
 /* Add your own CSS code below */
+.countries--first {
+  display: flex;
+  flex-direction: row;
+}
diff --git a/week-2/12-justify-content/flexbox.css b/week-2/12-justify-content/flexbox.css
index 3c4c7ff18..4394bac4a 100644
--- a/week-2/12-justify-content/flexbox.css
+++ b/week-2/12-justify-content/flexbox.css
@@ -7,3 +7,17 @@
 }
 
 /* Add your own CSS code below */
+.countries--first {
+  font-size: 0.9em;
+}
+.countries--second {
+  flex-direction: row;
+  justify-content: space-between;
+}
+.countries--third {
+  flex-direction: column-reverse;
+}
+.countries--fourth {
+  flex-direction: column;
+  justify-content: space-around;
+}
diff --git a/week-2/13-align-items/flexbox.css b/week-2/13-align-items/flexbox.css
index 3675a0df3..64bd639e4 100644
--- a/week-2/13-align-items/flexbox.css
+++ b/week-2/13-align-items/flexbox.css
@@ -2,3 +2,22 @@
   display: flex;
 }
 /* Add your own CSS code below */
+.countries--first {
+  flex-direction: row;
+  align-items: center;
+  font-size: 14px;
+}
+.countries--second {
+  flex-direction: row;
+  align-items: flex-end;
+  font-size: 14px;
+}
+.countries--third {
+  flex-direction: column;
+  align-items: flex-end;
+}
+.countries--fourth {
+  flex-direction: column;
+  align-items: center;
+  justify-content: flex-end;
+}
diff --git a/week-2/14-order/flexbox.css b/week-2/14-order/flexbox.css
index ed621b793..ed939ec7f 100644
--- a/week-2/14-order/flexbox.css
+++ b/week-2/14-order/flexbox.css
@@ -3,3 +3,24 @@
 }
 
 /* Add your own CSS code below */
+.countries--first :nth-child(1) {
+  order: 1;
+}
+.countries--second :nth-child(1) {
+  order: 1;
+}
+.countries--second :nth-child(5) {
+  order: 2;
+}
+.countries--third :nth-child(4) {
+  order: 1;
+}
+.countries--third :nth-child(3) {
+  order: 2;
+}
+.countries--third :nth-child(2) {
+  order: 3;
+}
+.countries--third :nth-child(1) {
+  order: 4;
+}
diff --git a/week-2/15-align-self/flexbox.css b/week-2/15-align-self/flexbox.css
index ed621b793..b0c7b5ec7 100644
--- a/week-2/15-align-self/flexbox.css
+++ b/week-2/15-align-self/flexbox.css
@@ -3,3 +3,36 @@
 }
 
 /* Add your own CSS code below */
+
+.countries--first :nth-child(3) {
+  align-self: flex-end;
+}
+.countries--second {
+  flex-direction: row;
+  align-items: center;
+}
+.countries--second :nth-child(3) {
+  align-self: flex-end;
+}
+
+.countries--third {
+  flex-direction: row;
+  align-items: flex-start;
+}
+.countries--third :nth-child(2) {
+  align-self: flex-end;
+}
+.countries--third :nth-child(3) {
+  align-self: flex-end;
+}
+.countries--third :nth-child(4) {
+  align-self: flex-end;
+}
+
+.countries--fourth {
+  flex-direction: column;
+  align-items: flex-start;
+}
+.countries--fourth :nth-child(5) {
+  align-self: center;
+}
diff --git a/week-2/16-more-flexbox/flexbox.css b/week-2/16-more-flexbox/flexbox.css
index ed621b793..d3d254523 100644
--- a/week-2/16-more-flexbox/flexbox.css
+++ b/week-2/16-more-flexbox/flexbox.css
@@ -3,3 +3,50 @@
 }
 
 /* Add your own CSS code below */
+.countries--first {
+  align-items: flex-end;
+}
+.countries--second {
+  align-items: flex-end;
+}
+.countries--second :nth-child(4) {
+  order: 1;
+}
+.countries--second :nth-child(3) {
+  order: 2;
+}
+.countries--second :nth-child(2) {
+  order: 3;
+}
+.countries--second :nth-child(1) {
+  order: 4;
+}
+
+.countries--third {
+  align-items: flex-start;
+}
+.countries--third :nth-child(1) {
+  align-self: flex-end;
+}
+.countries--fourth {
+  flex-direction: column;
+  align-items: flex-end;
+  justify-content: center;
+}
+.countries--fourth :nth-child(3) {
+  align-self: center;
+}
+.countries--fourth :nth-child(4) {
+  align-self: center;
+}
+.countries--fifth {
+  flex-direction: column-reverse;
+  align-items: flex-end;
+  justify-content: space-between;
+}
+.countries--fifth :nth-child(4) {
+  order: 1;
+}
+.countries--fifth :nth-child(5) {
+  align-self: center;
+}
diff --git a/week-2/17-nav-menu/styles.css b/week-2/17-nav-menu/styles.css
index f04f4c7ba..596aec0ed 100644
--- a/week-2/17-nav-menu/styles.css
+++ b/week-2/17-nav-menu/styles.css
@@ -1 +1,20 @@
 /* Write your media queries and flexbox CSS below */
+@media screen and (min-width: 480px) {
+  .site-header__nav {
+    display: flex;
+    flex-direction: row;
+  }
+}
+@media screen and (min-width: 700px) {
+  .side-header {
+    display: flex;
+    flex-direction: row;
+    justify-content: flex-start;
+  }
+}
+@media screen and (min-width: 992px) {
+  .site-header {
+    display: flex;
+    justify-content: space-between;
+  }
+}
diff --git a/week-2/18-git-merge/styles.css b/week-2/18-git-merge/styles.css
index 0051cdbaf..7a06a3a6f 100644
--- a/week-2/18-git-merge/styles.css
+++ b/week-2/18-git-merge/styles.css
@@ -1,6 +1,7 @@
 /* Add your own CSS code below */
 .link {
-  color: #4491db;
+  color: orangered;
   font-weight: 700;
   text-decoration: none;
+  background-color: palegreen;
 }
