WP PLUGIN アーカイブ毎に投稿表示順を設定する

・ベース部分（カテゴリー、投稿）の表示順用カスタムフィールド設定登録の作成

css/base.css

@@ -0,0 +1,77 @@
+@charset "UTF-8";
+
+.post-order-nav ul {
+    display: flex;
+    margin-bottom: 0;
+}
+
+.post-order-box {
+    width: 95%;
+    margin: 2em 0;
+
+}
+
+.post-order-nav li {
+    width: 20em;
+    padding: .5em;
+    margin-bottom: -1px;
+    font-size: 18px;
+    text-align: center;
+    background: #2c2c2e;
+    color: #fff;
+    cursor: pointer;
+    border-top-right-radius: 6px;
+    border-top-left-radius: 6px;
+    opacity: .5;
+}
+
+.post-order-nav li.en {
+    opacity: 1;
+}
+
+.post-order-nav li:first-child {
+    margin-right: .3em;
+}
+
+h3 {
+    font-weight: normal;
+    font-size: 16px;
+}
+
+.list-orders-outer {
+    width: 100%;
+    display: flex;
+    justify-content: flex-start;
+    flex-wrap: wrap;
+}
+
+.list-orders-inner {
+    width: calc((100% - 10px) / 3);
+    border: 1px solid #999;
+    background: #fff;
+    padding: .5em;
+}
+
+.post-order-list {
+    margin: .5em 1em 1em 0;
+}
+
+.product-list {
+    padding: .5em;
+    border-radius: 4px;
+    background: #2271B1;
+    cursor: move;
+    color: #fff;
+}
+
+.list_order {
+    width: 2em;
+}
+
+.sort-num-label::before {
+    content: "［";
+}
+
+.sort-num-label::after {
+    content: "］";
+}