https://i.sstatic.net/RDWfp.png
My layout is based on the bootstrap 4 grid system, as shown in the image above. The problem I'm facing is that the border at the bottom row is misaligned. I have four nested columns in the first and second rows, but only two columns in the last row. I want the border of the last row to align with the row above it.
Please provide assistance. Thank you! Fiddle Link
<div class="container mt-3">
<div class="row">
<div class="col-12">
<div class="row">
<div class="col-7 border">
<div class="row">
<label for="adf_bd_nationality" class="bg-gray-light d-flex border-right border-bottom-0 align-items-center col-7 col-form-label text-black col-form-label-sm">Registration (Tail No.)</label>
<div class="col-5 bg-white">
<input class="form-control" />
</div>
</div>
</div>
<div class="col-5 bg-white border border-md-left-0 ">
<div class="row">
<label for="adf_bd_serialNo" class="bg-gray-light d-flex border-md-right border-right border-bottom-0 border-top-0 align-items-center col-6 col-form-label text-black col-form-label-sm">Serial No.</label>
<div class="col-6">
<input type="text" class="form-control text-black text-center " id="adf_bd_serialNo" name="adf_bd_serialNo" onkeypress="return /[0-9a-zA-Z]/i.test(event.key)" maxlength="10">
</div>
</div>
</div>
</div>
</div>
<div class="col-12">
<div class="row">
<div class="col-7 border border-top-0 ">
<div class="row">
<label for="adf_bd_manufacturer" class="bg-gray-light d-flex border-right border-md-bottom-0 align-items-center col-7 col-form-label text-black col-form-label-sm">Manufacturer</label>
<div class="col-5 bg-white">
<select name="adf_bd_manufacturer" id="adf_bd_manufacturer" class="my-select form-control">
<option value="" class="bg-black">Select</option>
<option value="Airbus" class="bg-black">Airbus</option>
<option value="Boeing" class="bg-black">Boeing</option>
<option value="Bombardier" class="bg-black">Bombardier</option>
<option value="Embraer" class="bg-black">Embraer</option>
<option value="McDonnell Douglas" class="bg-black">McDonnell Douglas</option>
<option value="Tupoloev" class="bg-black">Tupoloev</option>
<option value="Cessna" class="bg-black">Cessna</option>
<option value="Cirrus Design" class="bg-black">Cirrus Design</option>
<option value="Diamond" class="bg-black">Diamond</option>
<option value="Mooney" class="bg-black">Mooney</option>
<option value="Piper" class="bg-black">Piper</option>
</select>
</div>
</div>
</div>
<div class="col-5 bg-white border border-top-0 border-md-left-0 ">
<div class="row">
<label for="adf_bd_ICAO" class="bg-gray-light d-flex border border-md-right border-bottom-0 border-md-bottom-0 border-top-0 border-left-0 align-items-center col-6 col-form-label text-black col-form-label-sm">Type ICAO</label>
<div class="col-6 ">
<input type="text" class="form-control text-black text-center" id="adf_bd_ICAO" name="adf_bd_ICAO" data-inputmask="'regex': '[a-zA-Z0-9]', 'repeat': 4, 'placeholder': ''" autocomplete="off" inputmode="text">
</div>
</div>
</div>
</div>
</div>
<div class="col-12">
<div class="row border border-top-0 ">
<label for="adf_bd_engineTypes" class="bg-gray-light d-flex border-right border-bottom-0 border-bottom align-items-center col-4 col-form-label text-black col-form-label-sm" style="">Engine Type(s)</label>
<div class="col-8 adf_bd_engineTypesCon bg-white" style="">
<input type="text" class="form-control text-black required " id="adf_bd_engineTypes" name="adf_bd_engineTypes" data-inputmask="'regex': '^[0-9a-zA-Z]', 'repeat': 15, 'placeholder': ''">
</div>
</div>
</div>
</div>
</div>