Do not rely on browser default styles because www resets

And make a few CSS rules a bit more specific to avoid other style defaults from www

src/components/language-selector/language-selector.css

@@ -10,6 +10,8 @@
     user-select: none;
     font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
     font-size: .875rem;
+    color: $text-primary;
+    background: $ui-white;
 }
 
 [dir="ltr"] .language-select {

src/components/loader/loader.css

@@ -154,6 +154,12 @@
   }
 }
 
+.title {
+    font-size: 2rem;
+    font-weight: bold;
+    margin: 0.75rem 0;
+}
+
 .message-container-outer {
     height: 30px;
     overflow: hidden;

src/components/loader/loader.jsx

@@ -147,13 +147,13 @@ class LoaderComponent extends React.Component {
                             src={bottomBlock}
                         />
                     </div>
-                    <h1 className={styles.title}>
+                    <div className={styles.title}>
                         <FormattedMessage
                             defaultMessage="Loading Project"
                             description="Main loading message"
                             id="gui.loader.headline"
                         />
-                    </h1>
+                    </div>
                     <div className={styles.messageContainerOuter}>
                         <div
                             className={styles.messageContainerInner}

src/components/menu-bar/menu-bar.css

@@ -55,6 +55,7 @@
 }
 
 .language-menu {
+    box-sizing: border-box;
     display: inline-flex;
     width: $language-selector-width;
 }

src/components/menu/menu.css

@@ -27,6 +27,9 @@
     line-height: 34px;
     white-space: nowrap;
     padding: 0 10px;
+    font-size: .75rem;
+    margin: 0;
+    font-weight: bold;
 }
 
 .menu-item.active,