Rotate threat model headers 45 degrees instead of 90.

index.bs

@@ -42,15 +42,41 @@ spec: PSL; urlPrefix: https://publicsuffix.org/
 <pre class='link-defaults'>
 </pre>
 <style>
-.threatmodel tr.goals th {
-  padding: 1ex;
-  max-height: 20em;
-}
-.threatmodel tr.goals th * {
-  writing-mode: vertical-rl;
+@supports(transform: rotate(45deg)) {
+/* Rotate threat model table headers to fit more columns on the screen.
+ * Details adapted from
+ * https://wabain.github.io/2019/10/13/css-rotated-table-header.html */
+  .threatmodel tr.goals th {
+    /* sin(45deg) == 0.707 */
+    height: calc((25em + 3em) * 0.707);
+    vertical-align: bottom;
+    text-align: right;
+    line-height: 1;
+  }
+  .threatmodel tr.goals th > div {
+    width: 5em;
+  }
+  .threatmodel tr.goals th > div > div {
+    width: 25em;
+    transform-origin: bottom left;
+    /* Read the transform steps bottom-up. */
+    transform:
+      /* Move the bottom corner from the left edge of the column to the center. */
+      translateX(calc(5em/2))
+      /* Rotate 45 degrees clockwise. */
+      rotate(45deg)
+      /* Move the bottom-right corner to the left edge of the column, which is
+       * the transform-origin. */
+      translateX(-100%);
+  }
+  .threatmodel tr.goals th a[href] {
+    border-bottom: 0;
+  }
 }
+
 .threatmodel td {
   text-align: center;
+  min-width: 2em;
 }
 details[open] {
   position: absolute;

xsite-tracking-model.bsinc

@@ -3,11 +3,11 @@
 <table class="threatmodel">
 <tr class="goals">
   <td></td>
-  <th>[[#goal-transfer-userid]]</th>
-  <th>[[#goal-userid-tracker-to-self-in-pub]]</th>
-  <th>[[#goal-userid-tracker-in-pub1-to-self-in-pub2]]</th>
-  <th>[[#goal-prob-transfer-userid-no-nav]]</th>
-  <th>[[#goal-prob-transfer-userid]]</th>
+  <th><div><div>[[#goal-transfer-userid]]</div></div></th>
+  <th><div><div>[[#goal-userid-tracker-to-self-in-pub]]</div></div></th>
+  <th><div><div>[[#goal-userid-tracker-in-pub1-to-self-in-pub2]]</div></div></th>
+  <th><div><div>[[#goal-prob-transfer-userid-no-nav]]</div></div></th>
+  <th><div><div>[[#goal-prob-transfer-userid]]</div></div></th>
 </tr>
 <tr>
   <th>[[#cap-iframes]]</th>
@@ -111,7 +111,7 @@ attacker-controlled javascript):
 <table class="threatmodel">
 <tr class="goals">
   <td></td>
-  <th>[[#goal-prob-transfer-userid-no-nav]]</th>
+  <th><div><div>[[#goal-prob-transfer-userid-no-nav]]</div></div></th>
 </tr>
 <tr>
   <th>[[#cap-type-identifier]]</th>