style: テーマカラーを青系(ブランドカラー)に統一

src/css/custom.css

@@ -1,26 +1,26 @@
 @import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;700&display=swap');
 
 :root {
-  --ifm-color-primary: #2e8555;
-  --ifm-color-primary-dark: #29784c;
-  --ifm-color-primary-darker: #277148;
-  --ifm-color-primary-darkest: #205d3b;
-  --ifm-color-primary-light: #33925d;
-  --ifm-color-primary-lighter: #359962;
-  --ifm-color-primary-lightest: #3cad6e;
+  --ifm-color-primary: #2563eb;
+  --ifm-color-primary-dark: #1d4ed8;
+  --ifm-color-primary-darker: #1e40af;
+  --ifm-color-primary-darkest: #1e3a8a;
+  --ifm-color-primary-light: #3b82f6;
+  --ifm-color-primary-lighter: #60a5fa;
+  --ifm-color-primary-lightest: #93c5fd;
   --ifm-code-font-size: 95%;
   --docusaurus-highlighted-code-line-bg: rgba(0, 0, 0, 0.1);
   --site-font-mono: 'JetBrains Mono', monospace;
 }
 
 [data-theme='dark'] {
-  --ifm-color-primary: #25c2a0;
-  --ifm-color-primary-dark: #21af90;
-  --ifm-color-primary-darker: #1fa588;
-  --ifm-color-primary-darkest: #1a8870;
-  --ifm-color-primary-light: #29d5b0;
-  --ifm-color-primary-lighter: #32d8b4;
-  --ifm-color-primary-lightest: #4fddbf;
+  --ifm-color-primary: #3b82f6;
+  --ifm-color-primary-dark: #2563eb;
+  --ifm-color-primary-darker: #1d4ed8;
+  --ifm-color-primary-darkest: #1e40af;
+  --ifm-color-primary-light: #60a5fa;
+  --ifm-color-primary-lighter: #93c5fd;
+  --ifm-color-primary-lightest: #bfdbfe;
   --docusaurus-highlighted-code-line-bg: rgba(0, 0, 0, 0.3);
 }
 
@@ -67,11 +67,11 @@
   border-color: var(--ifm-color-primary);
   border-left-color: var(--ifm-color-primary);
   transform: scale(1.02);
-  box-shadow: 0 0 16px rgba(46,133,85,0.25);
+  box-shadow: 0 0 16px rgba(37,99,235,0.25);
   text-decoration: none;
   color: inherit;
 }
 
 [data-theme="dark"] .theme-doc-markdown ul > li > a:hover {
-  box-shadow: 0 0 16px rgba(37,194,160,0.25);
+  box-shadow: 0 0 16px rgba(59,130,246,0.25);
 }