Pop up modal untuk tambah data

Saya mencoba menggunakan pop up modal untuk menambahkan data, saya melihat tutorial tapi ketika di submit, salah membaca link. data yang di folder proses harusnya insert ke database malah masuk ke url.

<a href="#" class="btn btn-success" data-target="#ModalAdd" data-toggle="modal">Add Data</a>

<div id="ModalAdd" class="modal fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-dialog">
    <div class="modal-content">

      <div class="modal-header">
            <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
            <h4 class="modal-title" id="myModalLabel"></h4>
        </div>

        <div class="modal-body">
          <form action="proses_save.php" name="modal_popup" enctype="multipart/form-data" method="POST">

                <div class="form-group" style="padding-bottom: 20px;">
                  <label for="Modal Name">Nama Kategori</label>
                  <input type="text" name="modal_name"  class="form-control" placeholder="Modal Name" required/>
                </div>
              <div class="modal-footer">
                  <button class="btn btn-success" type="submit">
                      Confirm
                  </button>

                  <button type="reset" class="btn btn-danger"  data-dismiss="modal" aria-hidden="true">
                    Cancel
                  </button>
              </div>

              </form>

Dan ketika di submit link nya jadi http://localhost/pt3mitra/Admin/post?modal_name=Bata+Ringan