diff --git a/_includes/style.scss b/_includes/style.scss
index b1e76cf..595f35e 100644
--- a/_includes/style.scss
+++ b/_includes/style.scss
@@ -26,9 +26,11 @@ $selection-font-color: #fff;
 
 // コンテナ
 $container-box-shadow: 0 0 10px 0 #ddd;
+$container-width: 80vw;
 
 // ヘッダ
 $header-background: #f2f2f2;
+$header-height: 3em;
 $header-link-color: #694;
 $header-mobile-box-shadow: 0 0 5px 2px rgba(0,0,0,0.3);
 $header-img-vertical-adjustment: -.4em;
@@ -57,9 +59,15 @@ $footer-text-color: #fff;
 // モバイルメニュー
 $mobile-menu-background: #555;
 $mobile-menu-text-color: #fff;
+$mobile-menu-width: 70vw;
+
+// トップに戻るボタン
+$top-button-opacity: 0.75;
 
 // Modなどのスクリーンショット
 $screenshot-background: #eee;
+$screenshot-max-height: 250px;
+$screenshot-max-width: 500px;
 
 // ----- インポート ----- //
 
diff --git a/_sass/_article.scss b/_sass/_article.scss
index eb2ef5f..d30f7ca 100644
--- a/_sass/_article.scss
+++ b/_sass/_article.scss
@@ -4,10 +4,7 @@
   padding: 0 1em 1em 1em;
 
   @include media-mobile {
-    // ヘッダの高さを計算
-    $line-height: ($font-size * 20 / 14);
-    $line-height-mobile: ($line-height * 1.1);
-    $top-padding: ($line-height-mobile * 3 - $font-size-mobile);
+    $top-padding: calc($header-height - $font-size-mobile);
 
     padding-top: $top-padding;
 
diff --git a/_sass/_container.scss b/_sass/_container.scss
index a2fceb8..bc41bb4 100644
--- a/_sass/_container.scss
+++ b/_sass/_container.scss
@@ -17,7 +17,7 @@
     // ~ IE11
     margin: 0 auto;
     min-height: 100vh;
-    width: 80vw;
+    width: $container-width;
 
     header {
       border-bottom: $border-default;
diff --git a/_sass/_header.scss b/_sass/_header.scss
index 6ea7984..7b16618 100644
--- a/_sass/_header.scss
+++ b/_sass/_header.scss
@@ -3,8 +3,8 @@ header {
   background: $header-background;
   box-sizing: border-box;
   font-weight: bold;
-  height: 3em;
-  line-height: 3em;
+  height: $header-height;
+  line-height: $header-height;
 
   @include media-desktop {
     padding: 0 1em;
diff --git a/_sass/_mobile.scss b/_sass/_mobile.scss
index 7d645ef..2014fb2 100644
--- a/_sass/_mobile.scss
+++ b/_sass/_mobile.scss
@@ -4,7 +4,7 @@ amp-sidebar {
   color: $mobile-menu-text-color;
   padding: 1em;
   text-align: center;
-  width: 75vw;
+  width: $mobile-menu-width;
 
   a {
     &:link,
@@ -38,7 +38,7 @@ amp-sidebar {
 }
 
 .top-button {
-  opacity: 0.75;
+  opacity: $top-button-opacity;
   position: fixed;
   right: 1em;
   bottom: 1em;
diff --git a/_sass/_screenshot.scss b/_sass/_screenshot.scss
index c1721ed..30ffdb6 100644
--- a/_sass/_screenshot.scss
+++ b/_sass/_screenshot.scss
@@ -1,8 +1,8 @@
 // スクリーンショット
 .screenshot {
   background: $screenshot-background;
-  max-height: 250px;
-  max-width: 500px;
+  max-height: $screenshot-max-height;
+  max-width: $screenshot-max-width;
 
   img {
     object-fit: contain;