on> (Ctrl+Enter)
                    </div>
                </div>

                <div class="form-group form-group-sm markdown-preview">
                    <label class="col-sm-1 control-label">预览</label>
                    <div class="col-sm-11">
                        <div id="content-preview" style="border: 1px solid #ccc; padding: 5px; font-size: 13px;" class="markdown-body"></div>
                    </div>
                </div>
            {{else}}
                <div class="text-center">
