website: adds sponsor button

docs/index.css

@@ -287,3 +287,34 @@ boxes.features grid .sample em {
 .features box.feat-cvXX {
   flex-basis: 100%;
 }
+
+
+
+#sponsor-button {
+  display: inline-block;
+  min-width: 1%;
+  max-width: 100%;
+  height: 2em;
+  line-height: 2em;
+  border-radius: 0.25em;
+  border: 1px solid rgba(0,0,0,0.2);
+  font-weight: 500; font-weight: 480;
+  text-decoration: none;
+  padding: 0 0.55em;
+  user-select: none; -webkit-user-select: none;
+}
+#sponsor-button:hover {
+  border-color: rgba(0,0,0,0.6);
+  color: inherit;
+}
+#sponsor-button span {
+  display: flex;
+  align-items: center;
+}
+#sponsor-button span::before {
+  content: "♥";
+  color: var(--red);
+  margin-right: 0.3em;
+  font-size: 1.1em;
+  line-height: 1em;
+}

docs/index.html

@@ -134,6 +134,13 @@ html { font-family: 'Inter', sans-serif; }
         You are free to use this font in almost any way imaginable.<br>
         Refer to the <a href="https://choosealicense.com/licenses/ofl-1.1/">SIL Open Font License 1.1</a> for exact details on what the conditions and restrictions are.
       </p>
+      <p>
+        <a id="sponsor-button"
+           title="Help Inter by becoming a sponsor and donating a coffee or two"
+           href="https://github.com/sponsors/rsms">
+           <span>Sponsor</span>
+        </a>
+      </p>
     </c>
 
   </grid>