docs: improve navigation readability

docs/theme/lore.css

@@ -14,16 +14,33 @@ html.ayu {
     --kaptan-muted: #888888;
     --kaptan-accent: #00ff41;
     --kaptan-border: #333333;
+
+    /* mdBook's generated content rules use these variables directly. */
+    --bg: #050505;
+    --fg: #e6e6e6;
+    --sidebar-bg: #0a0a0a;
+    --sidebar-fg: #e6e6e6;
+    --sidebar-non-existant: #888888;
+    --sidebar-active: #00ff41;
+    --sidebar-spacer: #333333;
+    --links: #00ff41;
+    --inline-code-color: #e6e6e6;
+    --quote-bg: #0a0a0a;
+    --quote-border: #333333;
+    --table-border-color: #333333;
+    --table-header-bg: #0a0a0a;
+    --table-alternate-bg: #080808;
+    --color-scheme: dark;
 }
 
 html,
 body {
     background: var(--kaptan-background);
-    color: var(--kaptan-text);
+    color: var(--fg);
     font-family: "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Monaco,
         Consolas, "Liberation Mono", monospace;
-    font-size: 15px;
-    line-height: 1.65;
+    font-size: 16px;
+    line-height: 1.7;
 }
 
 * {
@@ -56,7 +73,7 @@ body {
 #mdbook-menu-bar .menu-title {
     color: var(--kaptan-text);
     font-family: inherit;
-    font-size: 0.85rem;
+    font-size: 1rem;
     font-weight: 700;
     letter-spacing: 0.08em;
     line-height: 1.35;
@@ -88,9 +105,9 @@ body {
 .sidebar-scrollbox .chapter-item a {
     color: var(--kaptan-text);
     display: block;
-    font-size: 0.85rem;
-    line-height: 1.45;
-    padding: 0.3rem 1rem;
+    font-size: 1rem;
+    line-height: 1.5;
+    padding: 0.4rem 1rem;
     text-decoration: none;
 }
 
@@ -112,7 +129,7 @@ body {
 .content {
     box-sizing: border-box;
     margin: 0 auto;
-    max-width: 84ch;
+    max-width: 78ch;
     padding: 2rem 1.5rem 3rem;
 }
 
@@ -224,18 +241,9 @@ blockquote {
     padding-left: 0.8rem;
 }
 
-.nav-wrapper {
-    border-top: 1px solid var(--kaptan-border);
-    margin-top: 2rem;
-    padding-top: 0.75rem;
-}
-
-.nav-chapters {
-    background: none;
-}
-
-.nav-chapters a {
-    color: var(--kaptan-accent);
+.nav-wrapper,
+.nav-wide-wrapper {
+    display: none !important;
 }
 
 @media (min-width: 900px) {