Merge branch 'master' into translations

blog/static/css/main.css

@@ -82,10 +82,14 @@ main img {
   border: 2px solid #fc0
 }
 
-.posts.exceptions {
+.posts.interrupts {
   border: 2px solid #f66;
 }
 
+.posts.multitasking {
+  border: 2px solid #556b2f;
+}
+
 .posts hr {
   margin: 2rem 0;
 }
@@ -122,10 +126,14 @@ main img {
   color: #990;
 }
 
-.post-category.exceptions {
+.post-category.interrupts {
   color: #f33;
 }
 
+.post-category.multitasking {
+  color: #556b2f;
+}
+
 .post-footer-support {
   margin-top: 2rem;
 }
@@ -193,19 +201,26 @@ aside#all-posts-link {
     width: 12rem;
     position: sticky;
     float: left;
-    top: 1rem;
+    top: 3.5rem;
     margin-top: -4rem;
     margin-left: -15rem;
     font-size: 90%;
     line-height: 1.2;
+  }
+
+  #toc-aside li > a, #toc-aside h2 {
     opacity: .5;
     transition: opacity .5s;
   }
 
-  #toc-aside:hover {
+  #toc-aside:hover li > a, #toc-aside:hover h2 {
     opacity: 1;
   }
 
+  #toc-aside li.active > a {
+    font-weight: bold;
+  }
+
   #toc-aside h2 {
     font-size: 110%;
     margin-bottom: .2rem;
@@ -217,7 +232,7 @@ aside#all-posts-link {
     list-style:none;
   }
 
-  #toc-aside ol li:before {
+  #toc-aside ol li a:before {
     content: "";
     border-color: transparent #008eef;
     border-style: solid;
@@ -263,11 +278,10 @@ aside#all-posts-link {
   }
 
   aside#all-posts-link {
-    float: left;
-    position: absolute;
-    bottom: 0;
-    left: -15rem;
+    position: fixed;
+    top: 1.25rem;
     margin-top: 0;
+    margin-left: -15rem;
   }
 }
 

blog/static/js/main.js

@@ -3,6 +3,8 @@ window.onload = function() {
 
   if (container != null) {
     resize_toc(container);
+    toc_scroll_position(container);
+    window.onscroll = function() { toc_scroll_position(container) };
   }
 }
 
@@ -24,3 +26,38 @@ function resize_toc(container) {
     resizeId = setTimeout(resize, 300);
   };
 }
+
+function toc_scroll_position(container) {
+  if (container.offsetParent === null) {
+    // skip computation if ToC is not visible
+    return;
+  }
+  var items = container.querySelectorAll("li")
+
+  // remove active class for all items
+  for (item of container.querySelectorAll("li")) {
+    item.classList.remove("active");
+  }
+
+  // look for active item
+  var site_offset = document.documentElement.scrollTop;
+  var current_toc_item = null;
+  for (item of container.querySelectorAll("li")) {
+    if (item.offsetParent === null) {
+      // skip items that are not visible
+      continue;
+    }
+    var anchor = item.firstElementChild.getAttribute("href");
+    var heading = document.querySelector(anchor);
+    if (heading.offsetTop <= (site_offset + document.documentElement.clientHeight / 3)) {
+      current_toc_item = item;
+    } else {
+      break;
+    }
+  }
+
+  // set active class for current ToC item
+  if (current_toc_item != null) {
+    current_toc_item.classList.add("active");
+  }
+}