单元格之间的 SVG 伪影

var elem = document.getElementById('svg-canvas');
        var w = elem.offsetWidth;
        var h = elem.offsetHeight;
        var two = new Two({ width: w, height: h}).appendTo(elem);
        var settings = {
            def_padding: 20,
            cell_stroke: 'grey',
            cell_lw: 0,
            scale: 1.5,
        }
        var game = {
            width: 30,
            height: 30,
        }
function gen_cell(){
            return {
                kind: '#000000'
            };
        }
        function gen_field(){
            game.cells = [];
            for (let i = 0; i < game.height; i++) {
                game.cells[i] = [];
                for (let j = 0; j < game.width; j++) {
                    game.cells[i][j] = gen_cell();
                }
            }
        }
        var tmp_classes = [];
        function add_class_after(id, classname, attrs = []){
            tmp_classes.push([id, classname, attrs]);
            return id;
        }
        function reset_classes(){
            for (var i = 0; i < tmp_classes.length; i++) {
                $('#' + tmp_classes[i][0]).addClass(tmp_classes[i][1]);
            }
            tmp_classes = []
        }
        function draw(){
            two.clear();
            let size = Math.min((w - settings.def_padding)/game.width, (h - settings.def_padding)/game.height);
            let padding = {
                x: w - size*game.width,
                y: h - size*game.height,
            }
            for (let i = 0; i < game.cells.length; i++) {
                for (let j = 0; j < game.cells[i].length; j++) {
                    let cell = new Two.Rectangle(
                        j*size + padding.x/2 + size/2,
                        i*size + padding.y/2 + size/2,
                        size,
                        size
                        );
                    cell.stroke = settings.cell_stroke;
                    cell.linewidth = settings.cell_lw;
                    cell.fill = game.cells[i][j].kind;
                    cell.id = add_class_after(i + '-' + j, 'cell');
                    two.add(cell);
                }
            }
            two.update();reset_classes();
        }
        function scale(svg, e){
            let content = svg.find('g');
            let transform = content.attr('transform').split('(')[1].split(')')[0].split(' ').map(x => +x);
            let x = e.originalEvent.offsetX - content.width()/2;
            let y = e.originalEvent.offsetY - content.height()/2;
            let deltaY = e.originalEvent.deltaY;
            let scale_now = deltaY < 0 ? settings.scale : 1/settings.scale; 
            transform[0] *= scale_now;
            transform[3] *= scale_now;
            transform[4] = x - (x - transform[4])*scale_now;
            transform[5] = y - (y - transform[5])*scale_now;
            content.attr('transform', 'matrix(' + transform.join(' ') + ')');
        }
        function initialise(){
            $('#svg-canvas').html('');
            w = elem.offsetWidth;
            h = elem.offsetHeight;
            two = new Two({ width: w, height: h}).appendTo(elem);
            draw();
        }
        function move(svg, x, y){
            let transform = svg.find('g').attr('transform').split('(')[1].split(')')[0].split(' ').map(x => +x);
            transform[4] += x;
            transform[5] += y;
            svg.find('g').attr('transform', 'matrix(' + transform.join(' ') + ')');
        }
        $(document).ready(function(){
            gen_field();
            draw();
            $(window).resize(function(){
                initialise();
            });
            $('#svg-canvas').bind('mousewheel DOMMouseScroll', function(e){
                e.preventDefault();
            });
            $('body').bind('mousewheel DOMMouseScroll', '#svg-canvas svg', function(e){
                if(e.ctrlKey){
                    scale($(this), e);
                }
                else if(e.shiftKey){
                    move($(this), -e.originalEvent.deltaY/5, 0);
                }
                else{
                    move($(this), 0, -e.originalEvent.deltaY/5);
                }
            });
            $('body').on('mousedown', '#svg-canvas svg', function(e){
                if(e.which !== 2) return;
                e.preventDefault();
                $(this).css('cursor', 'move');
                let old_x = e.offsetX;
                let old_y = e.offsetY;
                $(this).mousemove(function(emove){
                    let x = emove.offsetX;
                    let y = emove.offsetY;
                    move($(this), emove.offsetX - old_x, emove.offsetY - old_y);
                    old_x = x;
                    old_y = y;
                });
                $(this).mouseup(function(){
                    $(this).off('mousemove');
                    $(this).css('cursor', 'default');
                });
                $(this).mouseleave(function(){
                    $(this).off('mousemove');
                    $(this).css('cursor', 'default');
                });
            });
        });

.cell:hover{
            opacity: 0.2;
        }
        .color, .condition{
            margin-bottom: 10px;
            border-left: 2px solid rgb(33, 37, 41);
        }
        .rule{
            margin-bottom: 10px;
        }
        #svg-canvas{
            width: 100%;
            height: 80vh;
        }
        #svg-canvas svg{
            background: lightgrey;
            border: 1px solid black;
        }

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/two.js/0.7.1/two.min.js"></script>
<div id="svg-canvas" class="main_field"></div>