diff --git a/public/base.html b/public/base.html
index b15017f..247138e 100644
--- a/public/base.html
+++ b/public/base.html
@@ -229,6 +229,14 @@
             .narrow-height {
                 line-height: 0;
             }
+            .unselectable {
+                -webkit-touch-callout: none;
+                -webkit-user-select: none;
+                -khtml-user-select: none;
+                -moz-user-select: none;
+                -ms-user-select: none;
+                user-select: none;
+            }
             .hide {
                 display: none;
             }
diff --git a/public/daily-quote.html b/public/daily-quote.html
index 1523720..0bd31e7 100644
--- a/public/daily-quote.html
+++ b/public/daily-quote.html
@@ -19,7 +19,7 @@
 {% endblock %}
 {% block content %}
             <p class="text-small text-bold"><a href="/" class="text-no-decoration">← ホーム</a></p>
-            <p class="text-highlight big-text"><span class="text-lowlight">"</span>{{ get_daily_quote() }}<span class="text-lowlight">"</span></p>
+            <p class="text-highlight big-text"><span class="text-lowlight unselectable">"</span>{{ get_daily_quote() }}<span class="text-lowlight unselectable">"</span></p>
             <div class="block">
                 <p>日替わり迷言集です。毎日0:00 UTCに更新されます。</p>
             </div>