チェックボタンは２つか３つなど複数で使うものですが、チェックボタンのどれかかひとつの
かっこのなかにcheckedを入れてください。

名前フォーム

<input type="checkbox" name="form" style="border-color:red;border-width:1px;border-style:solid;background:white;color:#000000;"> <input type="checkbox"name="form" style="border-color:#1E90FF;border-width:1px;border-style:solid;background:white;color:#000000;"> <input type="checkbox"name="form" style="border-color:#32CD32;border-width:1px;border-style:solid;background:white;color:#000000;"> <input type="checkbox"name="form" style="border-color:hotpink;border-width:1px;border-style:solid;background:white;color:#000000;"> <input type="checkbox"name="form" style="border-color:orange;border-width:1px;border-style:solid;background:white;color:#000000;"> <input type="checkbox"name="form" style="border-color:red;border-width:1px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:1px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:1px;border-style:dashed;background:white;color:#000000;"> <input type="text" name="form" style="border-color:hotpink;border-width:1px;border-style:dashed;background:white;color:#000000;"> <input type="text" name="form" style="border-color:orange;border-width:1px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:3px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:3px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:3px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:3px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:3px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:3px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:3px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:3px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:3px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:3px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:1px 0px;border-style:solid;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:1px 0px;border-style:solid;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:1px 0px;border-style:solid;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:1px 0px;border-style:solid;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:1px 0px;border-style:solid;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:1px 0px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:1px 0px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:1px 0px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:1px 0px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:1px 0px;border-style:dashed;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:3px 0px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:3px 0px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:3px 0px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:3px 0px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:3px 0px;border-style:dotted;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:red;border-width:3px 0px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#1E90FF;border-width:3px 0px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:#32CD32;border-width:3px 0px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:hotpink;border-width:3px 0px;border-style:double;background:white;color:#000000;"> <input type="checkbox" name="form" style="border-color:orange;border-width:3px 0px;border-style:double;background:white;color:#000000;">