mermaid/src/diagrams/class/styles.js

const getStyles = options =>
  `g.classGroup text {
  fill: ${options.nodeBorder};
  fill: ${options.classText};
  stroke: none;
  font-family: ${options.fontFamily};
  font-size: 10px;

  .title {
    font-weight: bolder;
  }
}
.node rect,
  .node circle,
  .node ellipse,
  .node polygon,
  .node path {
    fill: ${options.mainBkg};
    stroke: ${options.nodeBorder};
    stroke-width: 1px;
  }


.divider {
  stroke: ${options.nodeBorder};
  stroke: 1;
}

g.clickable {
  cursor: pointer;
}

g.classGroup rect {
  fill: ${options.nodeBkg};
  stroke: ${options.nodeBorder};
}

g.classGroup line {
  stroke: ${options.nodeBorder};
  stroke-width: 1;
}

.classLabel .box {
  stroke: none;
  stroke-width: 0;
  fill: ${options.nodeBkg};
  opacity: 0.5;
}

.classLabel .label {
  fill: ${options.nodeBorder};
  font-size: 10px;
}

.relation {
  stroke: ${options.lineColor};
  stroke-width: 1;
  fill: none;
}

.dashed-line{
  stroke-dasharray: 3;
}

#compositionStart, .composition {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#compositionEnd, .composition {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#dependencyStart, .dependency {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#dependencyStart, .dependency {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#extensionStart, .extension {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#extensionEnd, .extension {
  fill: ${options.lineColor} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#aggregationStart, .aggregation {
  fill: ${options.nodeBkg} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}

#aggregationEnd, .aggregation {
  fill: ${options.nodeBkg} !important;
  stroke: ${options.lineColor} !important;
  stroke-width: 1;
}
`;

export default getStyles;