Bootstrap 4

by jimkennelly

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.2/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.2/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootswatch/3.3.7/flatly/bootstrap.min.css">
<div class="container">
  
  
  <div class="col-md-12 p-0">
          <form method="POST" class="form m-0" id="sim_form" style="margin-bottom: 10px;">
          <input type="hidden" name="csrfmiddlewaretoken" value="esAgrRdmXdnAPsSPAAvfLe2kpesH5d3sprWU9MMWrfnuMxPmLDvE5o7efe7PsQpD">
          <div class="row">
            <div class="col-md-12">
                <button class="btn btn-success" id="sim_form_submit2" type="submit">Run Simulation</button>
                <div class="fa-3x" id="spinner2" style="display: none">
                  <i class="fas fa-spinner fa-spin" style="color: #28a745"></i>
                </div>
                <span class="alert alert-info" id="inputs_from_tab_banner" style="display: none"></span>
            </div>
          </div>

          <div class="card mt-2">
            <span class="card-header">Basics <small class="float-sm-right"><button class="btn btn-sm btn-info" id="button_investigation_options" type="button">Open Investigation Options</button></small></span>
            <div class="card-body">
              <div class="form-row">
                <div class="col-md-12" style="display: none" id="retirement_year_warning">
                  <p class="alert alert-warning text-center">Retirement End Year must be after Retirement Year.</p>
                </div>
                <div class="col-md-12" style="display: none" id="vpw_rate_of_return_warning">
                  <p class="alert alert-warning text-center">VPW Rate of Return must be > 0.</p>
                </div>
                <div class="form-group col-md-6">
                  <div class="input-group mb-2">
                  <div...

CSS

body {
    margin: 10px;
}