Sudhakar, Hemanth | Disabling the gray color highlighting on click in iOS devices

c3.css

 /*-- Chart --*/
 .c3 svg {
-  font: 10px sans-serif; }
+  font: 10px sans-serif;
+  -webkit-tap-highlight-color: rgba(0, 0, 0, 0); }
 
 .c3 path, .c3 line {
   fill: none;

c3.min.css

-.c3 svg{font:10px sans-serif}.c3 line,.c3 path{fill:none;stroke:#000}.c3 text{-webkit-user-select:none;-moz-user-select:none;user-select:none}.c3-bars path,.c3-event-rect,.c3-legend-item-tile,.c3-xgrid-focus,.c3-ygrid{shape-rendering:crispEdges}.c3-chart-arc path{stroke:#fff}.c3-chart-arc text{fill:#fff;font-size:13px}.c3-grid line{stroke:#aaa}.c3-grid text{fill:#aaa}.c3-xgrid,.c3-ygrid{stroke-dasharray:3 3}.c3-text.c3-empty{fill:gray;font-size:2em}.c3-line{stroke-width:1px}.c3-circle._expanded_{stroke-width:1px;stroke:#fff}.c3-selected-circle{fill:#fff;stroke-width:2px}.c3-bar{stroke-width:0}.c3-bar._expanded_{fill-opacity:.75}.c3-target.c3-focused{opacity:1}.c3-target.c3-focused path.c3-line,.c3-target.c3-focused path.c3-step{stroke-width:2px}.c3-target.c3-defocused{opacity:.3!important}.c3-region{fill:#4682b4;fill-opacity:.1}.c3-brush .extent{fill-opacity:.1}.c3-legend-item{font-size:12px}.c3-legend-item-hidden{opacity:.15}.c3-legend-background{opacity:.75;fill:#fff;stroke:#d3d3d3;stroke-width:1}.c3-tooltip-container{z-index:10}.c3-tooltip{border-collapse:collapse;border-spacing:0;background-color:#fff;empty-cells:show;-webkit-box-shadow:7px 7px 12px -9px #777;-moz-box-shadow:7px 7px 12px -9px #777;box-shadow:7px 7px 12px -9px #777;opacity:.9}.c3-tooltip tr{border:1px solid #CCC}.c3-tooltip th{background-color:#aaa;font-size:14px;padding:2px 5px;text-align:left;color:#FFF}.c3-tooltip td{font-size:13px;padding:3px 6px;background-color:#fff;border-left:1px dotted #999}.c3-tooltip td>span{display:inline-block;width:10px;height:10px;margin-right:6px}.c3-tooltip td.value{text-align:right}.c3-area{stroke-width:0;opacity:.2}.c3-chart-arcs-title{dominant-baseline:middle;font-size:1.3em}.c3-chart-arcs .c3-chart-arcs-background{fill:#e0e0e0;stroke:none}.c3-chart-arcs .c3-chart-arcs-gauge-unit{fill:#000;font-size:16px}.c3-chart-arcs .c3-chart-arcs-gauge-max,.c3-chart-arcs .c3-chart-arcs-gauge-min{fill:#777}.c3-chart-arc .c3-gauge-value{fill:#000}
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+.c3 svg{font:10px sans-serif;-webkit-tap-highlight-color:transparent}.c3 line,.c3 path{fill:none;stroke:#000}.c3 text{-webkit-user-select:none;-moz-user-select:none;user-select:none}.c3-bars path,.c3-event-rect,.c3-legend-item-tile,.c3-xgrid-focus,.c3-ygrid{shape-rendering:crispEdges}.c3-chart-arc path{stroke:#fff}.c3-chart-arc text{fill:#fff;font-size:13px}.c3-grid line{stroke:#aaa}.c3-grid text{fill:#aaa}.c3-xgrid,.c3-ygrid{stroke-dasharray:3 3}.c3-text.c3-empty{fill:gray;font-size:2em}.c3-line{stroke-width:1px}.c3-circle._expanded_{stroke-width:1px;stroke:#fff}.c3-selected-circle{fill:#fff;stroke-width:2px}.c3-bar{stroke-width:0}.c3-bar._expanded_{fill-opacity:.75}.c3-target.c3-focused{opacity:1}.c3-target.c3-focused path.c3-line,.c3-target.c3-focused path.c3-step{stroke-width:2px}.c3-target.c3-defocused{opacity:.3!important}.c3-region{fill:#4682b4;fill-opacity:.1}.c3-brush .extent{fill-opacity:.1}.c3-legend-item{font-size:12px}.c3-legend-item-hidden{opacity:.15}.c3-legend-background{opacity:.75;fill:#fff;stroke:#d3d3d3;stroke-width:1}.c3-tooltip-container{z-index:10}.c3-tooltip{border-collapse:collapse;border-spacing:0;background-color:#fff;empty-cells:show;-webkit-box-shadow:7px 7px 12px -9px #777;-moz-box-shadow:7px 7px 12px -9px #777;box-shadow:7px 7px 12px -9px #777;opacity:.9}.c3-tooltip tr{border:1px solid #CCC}.c3-tooltip th{background-color:#aaa;font-size:14px;padding:2px 5px;text-align:left;color:#FFF}.c3-tooltip td{font-size:13px;padding:3px 6px;background-color:#fff;border-left:1px dotted #999}.c3-tooltip td>span{display:inline-block;width:10px;height:10px;margin-right:6px}.c3-tooltip td.value{text-align:right}.c3-area{stroke-width:0;opacity:.2}.c3-chart-arcs-title{dominant-baseline:middle;font-size:1.3em}.c3-chart-arcs .c3-chart-arcs-background{fill:#e0e0e0;stroke:none}.c3-chart-arcs .c3-chart-arcs-gauge-unit{fill:#000;font-size:16px}.c3-chart-arcs .c3-chart-arcs-gauge-max,.c3-chart-arcs .c3-chart-arcs-gauge-min{fill:#777}.c3-chart-arc .c3-gauge-value{fill:#000}
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