update `public_html` static files

public_html/css/style.css

@@ -97,6 +97,10 @@ dd {
   padding-inline-start: 2ch;
 }
 
+figure {
+  margin-inline: 2ch;
+}
+
 ol, ul, menu {
   padding-inline-start: 5ch;
 }
@@ -121,7 +125,6 @@ hr {
 
 hr::after {
   content: "---";
-  font-weight: bold;
 }
 
 pre {
@@ -159,6 +162,13 @@ code {
 }
 
 
+/* image and multimedia */
+
+img {
+  max-width: 100%;
+}
+
+
 /* table content */
 
 table {
@@ -182,33 +192,27 @@ td {
 
 /* layout */
 
-body {
-  width: 100vw;
-	height: 100vh;
-}
-
-body>main {
-  width: 100%;
-  height: 100%;
+main {
+  height: 100vh;
 	display: grid;
   grid-auto-flow: column;
   grid-auto-columns: var(--col-w);
-  /*gap: 1ch;*/
 	overflow-x: scroll;
 }
 
-body>main>* {
+main>* {
   padding: 1rlh 1ch;
 	overflow-y: scroll;
 }
 
-/* toc */
+/* article.post */
 
-nav.toc {
+article.post>header,
+article.post>nav {
   margin-block: 1rlh;
 }
 
-/* fenced divs */
+/* div.horizontal */
 
 div.horizontal {
   display: grid;
@@ -222,7 +226,7 @@ div.horizontal>* {
   margin-block: unset;
 }
 
-/* math */
+/* .display.math */
 
 .display.math {
   display: block;