Bring back old newsbar styling for PromCon banner (#1917)

* Bring back old newsbar styling for PromCon banner

We already used a newsbar multiple times in the past, which was placed under
the main jumbotron and styled a bit more discreetly. I made some text + link
adjustments.

Signed-off-by: Julius Volz <[email protected]>

* Increase link boldness in newsbar

Signed-off-by: Julius Volz <[email protected]>

Author: juliusv

content/css/docs.css

@@ -126,6 +126,10 @@ body {
   margin-bottom: 50px;
 }
 
+.newsbar a {
+  font-weight: 400;
+}
+
 .feature-item {
   font-family: 'Lato', sans-serif;
   font-weight: 300;

content/index.html

@@ -1,11 +1,6 @@
 ---
 layout: jumbotron
 ---
-<div class="container">
-    <h3 style="color: #be3511" class="text-center">
-        <a href="https://promcon.io/2021-online/" style="color: #be3511">PromCon Online 2021, the Prometheus users conference, happens on May 3rd, 2021.</a>
-    </h3>
-</div>
 <div class="jumbotron">
   <div class="container">
     <h1>From metrics to insight</h1>
@@ -17,6 +12,10 @@ <h1>From metrics to insight</h1>
   </div>
 </div>
 
+<div class="newsbar">
+  Join <a href="https://promcon.io/2021-online/">PromCon Online 2021</a>, the Prometheus users conference, on May 3rd, 2021.</a>
+</div>
+
 <div class="container">
   <div class="row top-hr">
     <div class="col-md-3 col-sm-6 col-xs-12 feature-item">