itflow/vendor_add_modal.php

<div class="modal" id="addVendorModal" tabindex="-1">
  <div class="modal-dialog">
    <div class="modal-content bg-dark">
      <div class="modal-header">
        <h5 class="modal-title"><i class="fas fa-fw fa-building mr-2"></i>New Vendor</h5>
        <button type="button" class="close text-white" data-dismiss="modal">
          <span>&times;</span>
        </button>
      </div>
      <form action="post.php" method="post" autocomplete="off">

        <input type="hidden" name="client_id" value="<?php if (isset($_GET['client_id'])) { echo $client_id; } else { echo 0; } ?>">

        <div class="modal-body bg-white">

          <ul class="nav nav-pills nav-justified mb-3">
            <li class="nav-item">
              <a class="nav-link active" data-toggle="pill" href="#pills-details">Details</a>
            </li>
            <li class="nav-item">
              <a class="nav-link" data-toggle="pill" href="#pills-support">Support</a>
            </li>
            <li class="nav-item">
              <a class="nav-link" data-toggle="pill" href="#pills-notes">Notes</a>
            </li>
          </ul>

          <hr>

          <div class="tab-content">

            <div class="tab-pane fade show active" id="pills-details">

              <div class="form-group">
                <label>Vendor Name <strong class="text-danger">*</strong></label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-building"></i></span>
                  </div>
                  <input type="text" class="form-control" name="name" placeholder="Vendor Name" required autofocus>
                </div>
              </div>

              <div class="form-group">
                <label>Description</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-angle-right"></i></span>
                  </div>
                  <input type="text" class="form-control" name="description" placeholder="Description">
                </div>
              </div>

              <div class="form-group">
                <label>Account Number</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-fingerprint"></i></span>
                  </div>
                  <input type="text" class="form-control" name="account_number" placeholder="Account number">
                </div>
              </div>

              <div class="form-group">
                <label>Account Manager</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-user"></i></span>
                  </div>
                  <input type="text" class="form-control" name="contact_name" placeholder="Account manager's name">
                </div>
              </div>

            </div>

            <div class="tab-pane fade" id="pills-support">

              <label>Support Phone</label>
              <div class="form-row">
                <div class="col-8">
                  <div class="form-group">
                    <div class="input-group">
                      <div class="input-group-prepend">
                        <span class="input-group-text"><i class="fa fa-fw fa-phone"></i></span>
                      </div>
                      <input type="text" class="form-control" name="phone" placeholder="Phone Number">
                    </div>
                  </div>
                </div>
                <div class="col-4">
                  <input type="text" class="form-control" name="extension" placeholder="Prompts">
                </div>
              </div>

              <div class="form-group">
                <label>Support Hours</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-calendar"></i></span>
                  </div>
                  <input type="text" class="form-control" name="hours" placeholder="Support Hours">
                </div>
              </div>

              <div class="form-group">
                <label>Support Email</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-envelope"></i></span>
                  </div>
                  <input type="email" class="form-control" name="email" placeholder="Support Email">
                </div>
              </div>

              <div class="form-group">
                <label>Support Website URL</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-globe"></i></span>
                  </div>
                  <input type="text" class="form-control" name="website" placeholder="Do not include http(s)://">
                </div>
              </div>

              <div class="form-group">
                <label>Pin/Code</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-key"></i></span>
                  </div>
                  <input type="text" class="form-control" name="code" placeholder="Access Code or Pin">
                </div>
              </div>

              <div class="form-group">
                <label>SLA</label>
                <div class="input-group">
                  <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-handshake"></i></span>
                  </div>
                  <input type="text" class="form-control" name="sla" placeholder="SLA Response Time">
                </div>
              </div>

            </div>

            <div class="tab-pane fade" id="pills-notes">

              <div class="form-group">
                <textarea class="form-control" rows="8" placeholder="Enter some notes" name="notes"></textarea>
              </div>

            </div>

          </div>

        </div>
        <div class="modal-footer bg-white">
          <button type="submit" name="add_vendor" class="btn btn-primary text-bold"><i class="fas fa-check mr-2"></i>Create</button>
          <button type="button" class="btn btn-light" data-dismiss="modal"><i class="fa fa-times mr-2"></i>Cancel</button>
        </div>
      </form>
    </div>
  </div>
</div>