Improve portal landing page and About content (#215)

* First draft

* Improved Pythia text

* Improve text size, placement, and link color

* Apply suggestions from code review

Co-authored-by: Kevin Paul <[email protected]>

* Update portal/_static/custom.css

* Update portal/index.md

* Update portal/_static/custom.css

* Update portal/_static/custom.css

* Tweak the landing text and layout

* Happiness-producing compromise language!

* Finish updating About page and related text

* Use logos on About buttons

* Tweak About button layout

* Apply suggestions from code review

Co-authored-by: Kevin Paul <[email protected]>

* Add table of links to Pythia presentations

Co-authored-by: Kevin Paul <[email protected]>

Author: brian-rose

portal/_static/custom.css

@@ -1,3 +1,27 @@
+main.banner-main #project-pythia {
+  padding-top: 1rem;
+  padding-bottom: 1rem;
+}
+
+main.banner-main #project-pythia p {
+  font-size: 1.4rem;  /* default: 1.25rem */
+  /* font-weight: 700; default: 300 */
+}
+
+main.banner-main #project-pythia a,
+main.banner-main #project-pythia a:visited {
+  color: rgba(var(--spt-color-light), 1);
+  text-decoration: underline dotted rgba(var(--spt-color-gray-400), 1);
+}
+
+main.banner-main #project-pythia a.headerlink:hover {
+  color: #DDD;
+}
+
+main.banner-main #project-pythia a.btn-light {
+  color: rgba(var(--pst-color-primary), 1)
+}
+
 .modal {
   display: none;
   position: fixed;
@@ -87,3 +111,10 @@
     padding-bottom: 1rem;
   }
 }
+
+div.horizontalgap {
+  float: left;
+  overflow: hidden;
+  height: 1px;
+  width: 0px;
+}