New modern square design (#537)

* Create ion.rangeSlider.skinSquare.css

* Removed border-radius at labels

* Update ion.rangeSlider.skinSquare.css

* Update ion.rangeSlider.skinSquare.css

* Update ion.rangeSlider.skinSquare.css

Author: grimalschi

css/ion.rangeSlider.skinSquare.css

@@ -0,0 +1,87 @@
+/* Ion.RangeSlider, Square Skin
+// css version 2.2.0
+// © Denis Ineshin, 2014           https://github.com/IonDen
+// © Veaceslav Grimalschi, 2018    https://github.com/grimalschi
+// ===================================================================================================================*/
+
+/* =====================================================================================================================
+// Skin details */
+
+.irs {
+    height: 45px;
+    font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
+}
+
+.irs-with-grid {
+    height: 62px;
+}
+
+.irs-line {
+    top: 31px;
+    height: 4px;
+    background: #DEDEDE;
+}
+
+.irs-bar, .irs-bar-edge {
+    top: 31px;
+    height: 4px;
+    background: black;
+}
+.irs-bar-edge {
+    width: 8px;
+}
+
+.irs-shadow {
+    height: 2px;
+    top: 37px;
+    background: #DEDEDE;
+}
+
+.irs-slider {
+    top: 30px;
+    width: 10px;
+    height: 10px;
+    margin-top: -5px;
+    border: 3px solid black;
+    background: white;
+    cursor: pointer;
+    box-sizing: content-box;
+    -webkit-transform: rotate(45deg);
+    -ms-transform: rotate(45deg);
+    transform: rotate(45deg);
+}
+
+.irs-slider.state_hover, .irs-slider:hover {
+    background: #f0f0f0;
+}
+
+.irs-min, .irs-max {
+    color: #333;
+    font-size: 13px;
+    top: 0;
+    padding: 3px 4px;
+    background: rgba(0,0,0,0.1);
+    line-height: 1;
+}
+
+.irs-from, .irs-to, .irs-single {
+    color: #fff;
+    font-size: 13px;
+    text-shadow: none;
+    padding: 3px 4px;
+    background: black;
+    line-height: 1;
+}
+
+.irs-grid {
+    height: 27px;
+}
+.irs-grid-pol {
+    background: #DEDEDE;
+}
+
+.irs-grid-text {
+    bottom: 4px;
+    color: silver;
+    font-size: 11px;
+}