MisAlignment of page controls when page zoom out is performed

Question

Hi all, When i perform page zoom out the controls in that page are misaligned....

*This is the Screenshot-1*This is the original page

This is when i perform page zoom out:

Can any one pls help me solve this problem by providing some ideas or samples

This is my .ASPX page code

                        <label>
                            Viewer Contributed Content:<span class="hidden">*</span></label>
                        <input type="checkbox" id="chkviewer" runat="server"
                            tabindex="19" />&nbsp; <a id="lnkVCC" runat="server" href='<%=SessionUtilities.GetCustomizedURL("admin/ViewCategories.aspx?q=")+ApplicationUtilities.EncryptUrl("from=VCC&page=SM")%>'
                                onserverclick="LnkVccClick">Assign VCC Channel</a>
                    </div>
                    <div>
                        <label>
                            Enable Upload Video Button :<span class="hidden">*</span></label>
                        <asp:CheckBox ID="chkVccVisible" runat="server" TabIndex="20" />
                    </div>
    <div>
                        <label>
                            Enable Contact:<span class="hidden">*</span></label>
                        <asp:CheckBox ID="chkContact" runat="server" TabIndex="21" />
                    </div>

This is my CSS:

    fieldset{border:none;position:relative;}
    fieldset div {margin:.8em 0;}
   fieldset label{display:block;float:left;text-align:right;padding-right:10px;width:180px;cursor:pointer;}