diff --git a/assets/css/default.css b/assets/css/default.css
index 0b58af6..8de503c 100644
--- a/assets/css/default.css
+++ b/assets/css/default.css
@@ -1,73 +1,86 @@
 :root {
     --color-text: black;
     --color-tag1: gray;
-    --color-tag2: darkolivegreen;
     --color-bg: white;
     --color-notice: #fb4f4f;
     --color-link: #0645ad;
     --color-link-visited: #551a8b;
+    --layout-max-width: 1350px;
+    --mobile-max-width: 876px;
+    --content-max-width: 800px;
+    --toc-width: 33%;
+    --toc-width-no-sidenotes: 18rem;
 }
 
 html {
-    scrollbar-gutter: stable;
-    scroll-behavior: smooth;
     font-size: 110%;
+    scroll-behavior: smooth;
+    scrollbar-gutter: stable;
 }
 
 body {
-    font-family: 'Lato', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
+    font-family:
+        "Lato",
+        -apple-system,
+        BlinkMacSystemFont,
+        "PingFang SC",
+        "Microsoft YaHei",
+        sans-serif;
     font-optical-sizing: auto;
-    font-weight: 400;
-    font-style: normal;
     font-size: 1rem;
-    line-height: 140%;
+    line-height: 1.4;
     color: var(--color-text);
     background-color: var(--color-bg);
     text-rendering: optimizeLegibility;
 }
 
-body a {
+a {
     color: var(--color-link);
     text-decoration: none;
 }
 
-body a:visited {
+a:visited {
     color: var(--color-link-visited);
 }
 
-body a[href^="#"]:visited {
+a[href^="#"]:visited {
     color: var(--color-link);
 }
 
-body a:hover {
+a:hover {
     text-decoration: underline;
 }
+
 details {
     padding-left: 1em;
     border: 2px solid var(--color-text);
 }
+
 summary:hover {
     cursor: pointer;
 }
 
-/*mathML*/
-.htmlmathparagraph, mtext,math {
+/* Math */
+.htmlmathparagraph,
+math,
+mtext {
     font-family: Lete Sans Math;
 }
-.math-container,
-#math-container {
-	    display: block;
-	    overflow-x: auto;
-	    overflow-y: hidden;
-	    padding: .5em;
-	}
+
+#math-container,
+.math-container {
+    display: block;
+    overflow-x: auto;
+    overflow-y: hidden;
+    padding: 0.5em;
+}
 
 .equation {
     display: grid;
     grid-template-columns: minmax(0, 1fr) auto;
     align-items: center;
     column-gap: 1em;
-    margin: .5em 0;
+    margin: 0.5em 0;
 }
 
 .equation .math-container {
@@ -75,10 +88,11 @@ summary:hover {
 }
 
 .equation-number {
-    white-space: nowrap;
     font-style: normal;
+    white-space: nowrap;
 }
 
+/* Text */
 .text-space .langtag {
     color: var(--color-tag1);
 }
@@ -87,67 +101,69 @@ summary:hover {
     font-variant-caps: small-caps;
 }
 
+.uri,
 a.url {
-    word-break: break-all;
-}
-
-html body div.text-space main ul.post-list {
-    list-style-type: none;
-    padding-left: 1em;
-}
-
-/* top bar */
-header {
-    font-weight: 400;
-    font-family: "IosevkaC", sans-serif;
-    font-size: 2rem;
-    text-decoration: none;
-    line-height: 120%;
-    margin-top: 1rem;
-}
-
-.uri {
-    word-wrap: break-word;
     overflow-wrap: break-word;
     word-break: break-all;
     white-space: normal;
 }
 
+.post-list {
+    list-style: none;
+    padding-left: 1em;
+}
+
+header {
+    margin-top: 1rem;
+    font-size: 2rem;
+    font-weight: 400;
+    line-height: 1.2;
+}
+
 footer {
-    color: var(--color-text);
     font-size: 0.8rem;
     margin-top: 2em;
-    text-align: right;
     padding-right: 1em;
+    text-align: right;
 }
 
 .pagetitle {
     font-size: 2rem;
-    font-weight: normal;
-    font-style: normal;
+    font-weight: 400;
+    line-height: 1;
     text-align: left;
-    line-height: 100%;
+}
+
+.subtitle {
+    font-size: 1.2rem;
+    margin-top: 0;
+    text-align: left;
+}
+
+.draft-notice {
+    color: var(--color-notice);
+    margin: 1em auto;
+    text-align: center;
+}
+
+h1,
+h2,
+h3 {
+    margin-top: 1em;
+    font-style: normal;
+    font-weight: 700;
 }
 
 h1 {
-    margin-top: 1em;
     font-size: 1.44rem;
-    font-weight: bold;
-    font-style: normal;
 }
 
 h2 {
-    margin-top: 1em;
     font-size: 1.2rem;
-    font-weight: bold;
-    font-style: normal
 }
 
 h3 {
-    margin-top: 1em;
     font-size: 1rem;
-    font-weight: bold;
-    font-style: normal
 }
 
 section.body {
@@ -159,198 +175,186 @@ section.body {
     line-height: normal;
 }
 
-/* table. copied from https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements/table */
+/* Tables */
 table {
-  border-collapse: collapse;
-  border: 2px solid rgb(140 140 140);
-  font-size: 1rem;
+    border-collapse: collapse;
+    border: 2px solid rgb(140 140 140);
+    font-size: 1rem;
 }
 
 caption {
-  caption-side: bottom;
-  padding: 10px;
-  font-weight: bold;
+    caption-side: bottom;
+    padding: 10px;
+    font-weight: 700;
 }
 
 thead,
 tfoot {
-  background-color: rgb(228 240 245);
+    background-color: rgb(228 240 245);
 }
 
 th,
 td {
-  border: 1px solid rgb(160 160 160);
-  padding: 8px 10px;
+    border: 1px solid rgb(160 160 160);
+    padding: 8px 10px;
 }
 
 td:last-of-type {
-  text-align: center;
+    text-align: center;
 }
 
 tbody > tr:nth-of-type(even) {
-  background-color: rgb(237 238 242);
+    background-color: rgb(237 238 242);
 }
 
 tfoot th {
-  text-align: right;
+    text-align: right;
 }
 
 tfoot td {
-  font-weight: bold;
+    font-weight: 700;
 }
 
-
+/* Media */
 figure {
     display: flex;
     flex-flow: column;
-    padding: 5px;
-    margin: auto;
     max-width: 80%;
+    margin: auto;
+    padding: 5px;
 }
 
 .centerimg img {
-    margin: 0 auto 0 auto;
     display: block;
+    margin: 0 auto;
 }
 
-
-div.highlight,
+.highlight,
 pre code {
+    display: block;
     margin: auto;
     padding: 10px;
     overflow: auto;
-    display: block;
 }
 
 code {
-    font-family: "IosevkaC", monospace;
-    margin: 0 auto;
     display: inline-block;
-    padding: 0px 2px;
+    margin: 0 auto;
+    padding: 0 2px;
     border-radius: 2px;
+    font-family: "IosevkaC", monospace;
     font-variant-ligatures: none;
     font-kerning: none;
     text-rendering: optimizeSpeed;
 }
 
-
-.draft-notice {
-    color: var(--color-notice);
-    margin: 1em auto;
-    text-align: center
-}
-
-
-.subtitle {
-    text-align: left;
-    font-size: 1.2rem;
-    margin-top: 0
-}
 .gallery {
-    margin-top: 2em;
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
     gap: 12px;
+    margin-top: 2em;
 }
 
 .gallery img {
+    display: block;
     width: 100%;
     max-width: 320px;
-    display: block;
-}
-
-/* phones -- no sidebar no sidenotes*/
-@media (max-width: 768px) {
-    body {
-        /* width: 90%; */
-        margin: auto;
-        padding: 0 5%;
-        text-align: left;
-        max-width: 876px;
-    }
-    mjx-container[display="true"]
-    /*, .katex-display */ {
-        overflow-x: auto;
-        overflow-y: hidden;
-    }
-
-    /* .katex-display>.katex>.katex-html>.tag {
-        display: inline-block;
-        position: relative;
-        padding-left: 10pt;
-    } */
 }
 
+/* Layout */
 .toc {
     display: none;
 }
 
-/* sidebar. no sidenotes */
+@media (max-width: 768px) {
+    body {
+        max-width: var(--mobile-max-width);
+        margin: auto;
+        padding: 0 5%;
+        text-align: left;
+    }
+
+    mjx-container[display="true"] {
+        overflow-x: auto;
+        overflow-y: hidden;
+    }
+}
+
 @media (min-width: 769px) {
     body {
-        max-width: 1350px;
-        display: -webkit-flex;
-        -webkit-flex-flow: row wrap;
-        display: -ms-flexbox;
-        -ms-flex-flow: row wrap;
+        display: flex;
         flex-flow: row wrap;
         width: 95%;
-        padding-right: 5%;
+        max-width: var(--layout-max-width);
         margin: auto;
+        padding-right: 5%;
     }
 
     .toc {
+        display: block;
+        width: var(--toc-width);
         margin-top: 5rem;
-        margin-left: 0;
-        margin-right: 0;
-        width: 33%;
-        display: inline-block;
     }
 
-    div#contents ul,
-    div#contents-big ul {
-        margin-top: 0.5em;
-        margin-bottom: 0.5em;
+    #contents ul,
+    #contents-big ul {
+        list-style: none;
+        margin: 0.5em 0;
         padding-left: 1em;
         line-height: 1.2;
-        list-style-type: none;
-        margin-left: 0
     }
 
-    div#contents-big li+li {
-        margin-top: 0.5em
+    #contents-big li + li {
+        margin-top: 0.5em;
     }
 
-    div#contents-big .toc-section-number {
+    #contents-big .toc-section-number {
         margin-right: 0.2em;
     }
 
-    div#contents-big {
-        font-size: 80%;
-        padding-top: 0;
-        padding-left: 1rem;
-        text-align: left;
-        max-width: 60%;
-        clear: both;
-        margin-right: 4em;
+    #contents-big {
         position: sticky;
         top: 5rem;
-        left: 100%
+        left: 100%;
+        clear: both;
+        max-width: 60%;
+        margin-right: 4em;
+        padding-left: 1rem;
+        font-size: 80%;
+        text-align: left;
     }
 
-    div#contents-big .mini-header {
-        font-weight: bold;
+    #contents-big .mini-header {
         margin: 0;
         font-variant: small-caps;
+        font-weight: 700;
     }
 
     .text-space {
-        display: inline-block;
         width: 66%;
-        max-width: 800px;
+        max-width: var(--content-max-width);
+        min-width: 0;
     }
 }
-/* sidebar+sidenotes */
+
+@media (min-width: 769px) and (max-width: 1199px) {
+    .toc {
+        flex: 0 0 var(--toc-width-no-sidenotes);
+        width: var(--toc-width-no-sidenotes);
+    }
+
+    #contents-big {
+        max-width: none;
+        margin-right: 2rem;
+    }
+
+    .text-space {
+        flex: 1 1 0;
+        width: auto;
+        max-width: none;
+    }
+}
+
 @media (min-width: 1200px) {
     body {
         width: 75%;
@@ -359,7 +363,6 @@ code {
 }
 
 @media print {
-
     .no-print,
     .no-print * {
         display: none !important;
diff --git a/assets/css/sidenotes.css b/assets/css/sidenotes.css
index 4468400..5c6fef1 100644
--- a/assets/css/sidenotes.css
+++ b/assets/css/sidenotes.css
@@ -31,7 +31,7 @@ body {
     position: relative;
     text-align: left;
 }
-@media (max-width: 1200px) {
+@media (max-width: 1199px) {
     .sidenote,
     .marginnote,
     .marginnote-left {
@@ -142,7 +142,7 @@ label.margin-toggle:not(.sidenote-number) {
     height: 100%;
 }
 
-@media (max-width: 1200px) {
+@media (max-width: 1199px) {
     label.margin-toggle:not(.sidenote-number) {
         display: inline;
     }
diff --git a/assets/templates/default.html b/assets/templates/default.html
index 0c0e45a..6052c6d 100644
--- a/assets/templates/default.html
+++ b/assets/templates/default.html
@@ -25,7 +25,6 @@
     </div>
     <div class="text-space">
         <header class="no-print">
-            <a href="/">/</a>
             $title$
         </header>
         <main role="main">
@@ -39,4 +38,4 @@
     </div>
 </body>
 
-</html>
\ No newline at end of file
+</html>