JavascriptのWebスライド枚数変え方

SwiperとSVGのviewboxを使って
スライド表示してますが
枚数の変更方法が不明です。
SwiperのslidesPerColumnがスライド枚数と
書いてありましたが、このコードでは
slidesPerColumnを設定してないようです。
設定してないのに３枚数スライドできるのが不思議です。
どなたか教えてください。

こちらサイトでスライド貼ってます↓
https://jpthing.blogspot.jp/2018/03/blog-post.html

html
1<link href="https://cdnjs.cloudflare.com/ajax/libs/Swiper/3.4.1/css/swiper.min.css" rel="stylesheet"></link>
2
3
4    <script src="https://cdnjs.cloudflare.com/ajax/libs/Swiper/3.4.1/js/swiper.min.js"></script>
5<!-- Slider main container -->
6<br />
7<div class="sample sample02">
8<div class="swiper-container">
9<div class="swiper-wrapper">
10<div class="swiper-slide">
11<div class="sample02-inner">
12<a href="http://site-helpful.blogspot.jp/2017/07/kesenai-popup-virus.html"><img border="0" data-original-height="189" data-original-width="267" src="https://1.bp.blogspot.com/-jXTFPK6E-Tw/WqUTX3Sf4QI/AAAAAAAAFOk/9Z43_A_52u0XuD2uQx3id6wpiNK6kpncQCLcBGAs/s1600/alert.jpg" /></a>
13</div>
14</div>
15<div class="swiper-slide">
16<div class="sample02-inner">
17<a href="http://site-helpful.blogspot.jp/2017/10/soudan-madoguchi.html"><img border="0" data-original-height="189" data-original-width="302" src="https://2.bp.blogspot.com/-ldJCP8maROQ/WqUUwjy9hwI/AAAAAAAAFO4/X8inYjdSL_IXRNnA3S-DgO_qZc6sC41ewCLcBGAs/s1600/%25E7%259B%25B8%25E8%25AB%2587%25E7%25AA%2593%25E5%258F%25A3.jpg" /></a></div>
18</div>
19<div class="swiper-slide">
20<div class="sample02-inner">
21<a href="http://site-helpful.blogspot.jp/2016/10/survival.html">
22<img height="211" src="https://4.bp.blogspot.com/-T_sSe9wwOi0/WJka2BrnyKI/AAAAAAAAEWc/pEOTdRnJgOYVg7BX3FqMKANgpIsA-VMNACLcB/s320/982719a3.jpg" width="320" /></a></div>
23</div>
24</div>
25<div class="swiper-button-prev">
26<svg viewbox="0 0 27 44" xmlns="http://www.w3.org/2000/svg">
27        <path class="c-arrow c-arrow-prev" d="M0,22L22,0l2.1,2.1L4.2,22l19.9,19.9L22,44L0,22L0,22L0,22z">
28      </path></svg>
29    </div>
30<div class="swiper-button-next">
31<svg viewbox="0 0 27 44" xmlns="http://www.w3.org/2000/svg">
32        <path class="c-arrow c-arrow-next" d="M27,22L27,22L5,44l-2.1-2.1L22.8,22L2.9,2.1L5,0L27,22L27,22z">
33      </path></svg>
34    </div>
35<div class="swiper-pagination">
36</div>
37</div>
38</div>
39<style>
40.sample02 .swiper-wrapper {
41  align-items: stretch;
42}
43*{box-sizing: border-box;}
44.sample02 .swiper-slide {
45  display: flex;
46  justify-content: center;
47  align-items: center;
48  height: auto;
49  padding-bottom: 25px;
50}
51
52.sample02 .sample02-inner {
53  display: flex;
54  justify-content: center;
55  align-items: center;
56  width: 100%;
57}
58
59.sample02 .swiper-button-prev,
60.sample02 .swiper-button-next {
61  display: none;
62  width: 20px;
63  height: 32.58px;
64  fill: #666;
65  stroke: none;
66  stroke-width: 0;
67  background-image: none;
68  z-index: 10000;
69}
70
71.sample02 .swiper-container-horizontal > .swiper-pagination-bullets {
72  bottom: 0;
73}
74
75.sample02 .swiper-pagination-bullet-active {
76  background: #666;
77}
78
79@media (min-width: 768px) {
80  .sample02 .swiper-slide {
81    padding: 50px;
82  }
83
84  .sample02 .swiper-button-prev,
85  .sample02 .swiper-button-next {
86    display: block;
87  }
88
89  .sample02 .swiper-container-horizontal > .swiper-pagination-bullets {
90    bottom: 10px;
91  }
92}
93</style>
94<script>
95window.addEventListener('DOMContentLoaded', function() {
96  var swiper = new Swiper('.sample02 .swiper-container', {
97    pagination: '.swiper-pagination',
98    paginationClickable: true,
99    nextButton: '.swiper-button-next',
100    prevButton: '.swiper-button-prev',
101    loop: true,
102    speed: 500,
103    autoplay: 3000,
104    spaceBetween: 0,
105    effect: 'coverflow'
106  });
107}, false);
108</script>