fix storage mining with space saver

mining.html

@@ -19,7 +19,7 @@ body
 <body lang="ja">
 <p>Tab separated values. Spelling, readings, definitions, (if stored: looked up text, sentence, location in sentence), JMdict numeric ID.</p>
 <input type=button id=reset value="Reset"/>
-<textarea id="field" style="width:100%; height:calc(100% - 70px);"></textarea>
+<textarea id="field" style="width:100%; height: calc(100vh - 150px)"></textarea>
 </body>
 
 </html>