moving from webpack with really big project and have solve all problems in one day but this one seems like a bug.
Have try all 2.0 + versions.

In scss file have this.

$bg-light: "data:image/svg+xml;base64, "BIGDATA ++++";

.className {
      background-image: url($bg-light);
      background-size: 300px;
    }


[plugin:vite:css] expected ")".
       ╷
213 │       background-image: url(../../../assets/scss//$bg-light);
       │                                            ^
       ╵

Same project working with webpack.

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