_content: All releases page update

This update is to the /dl page design.

- Page title updated
- Table updated to reflect design
- spacing/color adjustments to match design

Video: https://drive.google.com/file/d/1Yhov_7v4h6vS9lQlQuuVqF3T3M-dXQnU/view?usp=sharing

Change-Id: Ifc7d8ad64b99e5ec44f4b2be657082ef20f30fa5
Reviewed-on: https://go-review.googlesource.com/c/website/+/442515
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Run-TryBot: Jamal Carvalho <jamal@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Jamal Carvalho <jamal@golang.org>
diff --git a/_content/css/styles.css b/_content/css/styles.css
index a875d18..303fa69 100644
--- a/_content/css/styles.css
+++ b/_content/css/styles.css
@@ -4549,6 +4549,43 @@
 }
 .toggleButton {
   cursor: pointer;
+  background-color: var(--color-background-accented);
+  padding: 0.5rem;
+}
+h3.toggleButton {
+  font-style: normal;
+  font-weight: 500;
+  font-size: 1rem;
+  line-height: 1.5rem;
+  padding-left: 1rem;
+  display: flex;
+  align-items: center;
+}
+#archive h2.toggleButton {
+  background-color: var(--color-background);
+}
+.toggleButton span.toggleText {
+  font-style: normal;
+  font-weight: 400;
+  font-size: 1rem;
+  line-height: 1.5rem;
+  color: var(--color-text-link);
+  margin-left: 0.625rem;
+}
+.toggleButton-img {
+  display: block;
+}
+.toggleButton-img-dark {
+  display: none;
+}
+[data-theme='dark'] .toggleButton-img {
+  display: none;
+}
+[data-theme='dark'] .toggleButton-img-dark {
+  display: block;
+}
+.toggle .collapsed img {
+  transform: rotate(180deg);
 }
 .toggle > .collapsed {
   display: block;
@@ -4805,16 +4842,34 @@
   height: 2.5rem;
 }
 table.downloadtable {
-  margin-left: 20px;
-  margin-right: 20px;
+  width: 100%;
   border-collapse: collapse;
 }
-table.downloadtable tr {
-  background-color: var(--color-background-accented);
+table.downloadtable thead {
+  border: 2px solid var(--color-background-accented);
 }
 table.downloadtable tr:nth-child(2n),
-table.downloadtable tr.first {
+table.downloadtable tr.first,
+table.downloadtable tr {
   background-color: var(--color-background);
+  border: 2px solid var(--color-background-accented);
+}
+
+table.downloadtable tr.first th {
+  text-align: left;
+  font-style: normal;
+  font-weight: 500;
+  font-size: 1rem;
+  line-height: 1.5rem;
+}
+table.downloadtable td {
+  font-style: normal;
+  font-weight: 400;
+  font-size: 1rem;
+  line-height: 1.5rem;
+}
+table.downloadtable td.filename, table.downloadtable tr.first th:nth-child(1) {
+  padding-left: 4.5rem;
 }
 table.downloadtable td,
 table.downloadtable th {
diff --git a/_content/dl.tmpl b/_content/dl.tmpl
index 623088f..4cc17e9 100644
--- a/_content/dl.tmpl
+++ b/_content/dl.tmpl
@@ -54,10 +54,10 @@
 {{with .Archive}}
 <div class="toggle" id="archive">
   <div class="collapsed">
-    <h2 class="toggleButton" title="Click to show versions">Archived versions ▸</h2>
+    <h2 class="toggleButton" title="Click to show versions">Archived versions <span class="toggleText">Show</span></h2>
   </div>
   <div class="expanded">
-    <h2 class="toggleButton" title="Click to hide versions">Archived versions ▾</h2>
+    <h2 class="toggleButton" title="Click to hide versions">Archived versions <span class="toggleText">Hide</span></h2>
     {{template "download-releases" .}}
   </div>
 </div>
@@ -105,10 +105,18 @@
 {{range .}}
 <div class="toggle{{if .Visible}}Visible{{end}}" id="{{.Version}}">
 	<div class="collapsed">
-		<h3 class="toggleButton" title="Click to show downloads for this version">{{.Version}} ▸</h3>
+		<h3 class="toggleButton" title="Click to show downloads for this version">
+    <img class="toggleButton-img" src="/images/icons/arrow-down.svg" width="18" height="18" aria-hidden="true" />
+    <img class="toggleButton-img toggleButton-img-dark" src="/images/icons/arrow-down-dark.svg" width="18" height="18" aria-hidden="true" />
+    <span>{{.Version}}</span>
+    </h3>
 	</div>
 	<div class="expanded">
-		<h3 class="toggleButton" title="Click to hide downloads for this version">{{.Version}} ▾</h3>
+		<h3 class="toggleButton" title="Click to hide downloads for this version">
+    <img class="toggleButton-img" src="/images/icons/arrow-down.svg" width="18" height="18" aria-hidden="true" />
+    <img class="toggleButton-img toggleButton-img-dark" src="/images/icons/arrow-down-dark.svg" width="18" height="18" aria-hidden="true" />
+    <span>{{.Version}}</span>
+    </h3>
 		{{if .Stable}}{{else}}
 			<p>This is an <b>unstable</b> version of Go. Use with caution.</p>
 			<p>If you already have Go installed, you can install this version by running:</p>
diff --git a/_content/images/icons/arrow-down-dark.svg b/_content/images/icons/arrow-down-dark.svg
new file mode 100644
index 0000000..4d22b9a
--- /dev/null
+++ b/_content/images/icons/arrow-down-dark.svg
@@ -0,0 +1,16 @@
+<svg version="1.2" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 18 18" width="18" height="18">
+	<title>arrow-down-svg</title>
+	<defs>
+		<clipPath clipPathUnits="userSpaceOnUse" id="cp1">
+			<path d="m12.75 7.5l-3.75 3.75-3.75-3.75z"/>
+		</clipPath>
+		<image  width="18" height="18" id="img1" href="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAASAQMAAABsABwUAAAAAXNSR0IB2cksfwAAAANQTFRF9fX1sGmfigAAAAxJREFUeJxjYKAOAAAASAABLrg8fgAAAABJRU5ErkJggg=="/>
+	</defs>
+	<style>
+	</style>
+	<g id="Clip-Path" clip-path="url(#cp1)">
+		<g id="Layer">
+			<use id="Layer" href="#img1" x="0" y="0"/>
+		</g>
+	</g>
+</svg>
\ No newline at end of file
diff --git a/_content/images/icons/arrow-down.svg b/_content/images/icons/arrow-down.svg
new file mode 100644
index 0000000..7177a6b
--- /dev/null
+++ b/_content/images/icons/arrow-down.svg
@@ -0,0 +1 @@
+<svg width="18" height="18" fill="none" xmlns="http://www.w3.org/2000/svg"><mask id="a" style="mask-type:alpha" maskUnits="userSpaceOnUse" x="5" y="7" width="8" height="5"><path d="M5.25 7.5 9 11.25l3.75-3.75h-7.5Z" fill="#fff"/></mask><g mask="url(#a)"><path fill="#5F6368" d="M18 0v18H0V0z"/></g></svg>
\ No newline at end of file
diff --git a/internal/dl/server.go b/internal/dl/server.go
index f9f21de..101fc4b 100644
--- a/internal/dl/server.go
+++ b/internal/dl/server.go
@@ -72,7 +72,7 @@
 	}
 
 	h.site.ServePage(w, r, web.Page{
-		"title":  "Downloads",
+		"title":  "All releases",
 		"layout": "dl",
 		"dl":     d,
 	})