Thanks @Bettencourt
I did create my own splash page. However after inputting email and password on the form nothing happen. I don't know what to add to interact with the meraki Cloud.
<div id="signin_form" class="formarea">
<form>
<label for="username">EMAIL</label>
<input type="text" id="username" name="username">
<label for="password">PASSWORD</label>
<input type="password" id="password" name="password">
<input class="btn btn-default" id="sign_in" name="sign_in" type="submit" value="Sign In">
</form>
<div class="form_links $MERAKI:HIDDEN_UNLESS_CAN_CREATE_ACCOUNT$">
<a class="toggle_link" id="create_account_link" href="#">$MERAKI:AUTH_CREATE_ACCOUNT_TITLE$</a>
</div>
</div>