diff --git a/packages/studio/package.json b/packages/studio/package.json
index ed578630c1..d55db2d58f 100644
--- a/packages/studio/package.json
+++ b/packages/studio/package.json
@@ -52,6 +52,7 @@
     "test:webmcp-edit-loop": "node tests/e2e/webmcp-edit-loop.mjs",
     "test:timeline-virtualization": "TIMELINE_ROW_VIRTUALIZATION=on TIMELINE_ELEMENT_COUNT=50000 node tests/e2e/timeline-virtualization.mjs",
     "test:watch": "vitest",
+    "test:colors:browser": "node tests/e2e/native-css-colors.mjs",
     "report:sdk-cutover": "bun src/utils/sdkCutoverPolicy.report.ts",
     "test:timeline-default": "bun run test:timeline-virtualization"
   },
diff --git a/packages/studio/src/components/editor/colorValue.test.ts b/packages/studio/src/components/editor/colorValue.test.ts
index fe0cb0b97d..b3cd2eefb2 100644
--- a/packages/studio/src/components/editor/colorValue.test.ts
+++ b/packages/studio/src/components/editor/colorValue.test.ts
@@ -28,6 +28,22 @@ describe("parseCssColor", () => {
     });
   });
 
+  it.each([
+    ["#0f172acc", { red: 15, green: 23, blue: 42, alpha: 0.8 }],
+    ["#f008", { red: 255, green: 0, blue: 0, alpha: 136 / 255 }],
+    ["rgb(255 0 0 / 50%)", { red: 255, green: 0, blue: 0, alpha: 0.5 }],
+    ["rgb(100% 0% 0% / 0.001)", { red: 255, green: 0, blue: 0, alpha: 0.001 }],
+  ])("parses %s without a browser", (input, expected) => {
+    expect(parseCssColor(input)).toEqual(expected);
+  });
+
+  it.each(["", "#12", "notacolor", "currentcolor", "none", "rgb(1..2, 3, 4)"])(
+    "rejects %s without a browser",
+    (input) => {
+      expect(parseCssColor(input)).toBeNull();
+    },
+  );
+
   it("parses transparent", () => {
     expect(parseCssColor("transparent")).toEqual({
       red: 0,
diff --git a/packages/studio/src/components/editor/colorValue.ts b/packages/studio/src/components/editor/colorValue.ts
index b2cb7bef8b..4a2a6ee4ef 100644
--- a/packages/studio/src/components/editor/colorValue.ts
+++ b/packages/studio/src/components/editor/colorValue.ts
@@ -29,49 +29,94 @@ function formatAlpha(value: number): string {
   return `${roundToCenti(clampAlpha(value))}`;
 }
 
-export function parseCssColor(value: string): ParsedColor | null {
+function parseComponent(value: string, scale: number): number {
+  return value.endsWith("%") ? (Number(value.slice(0, -1)) * scale) / 100 : Number(value);
+}
+
+function parseSerializedColor(value: string): ParsedColor | null {
   const trimmed = value.trim().toLowerCase();
   if (!trimmed) return null;
   if (trimmed === "transparent") {
     return { red: 0, green: 0, blue: 0, alpha: 0 };
   }
 
-  const shortHex = trimmed.match(/^#([0-9a-f]{3})$/i);
-  if (shortHex) {
-    const [r, g, b] = shortHex[1].split("");
-    return {
-      red: Number.parseInt(r + r, 16),
-      green: Number.parseInt(g + g, 16),
-      blue: Number.parseInt(b + b, 16),
-      alpha: 1,
-    };
-  }
-
-  const hex = trimmed.match(/^#([0-9a-f]{6})$/i);
+  const hex = trimmed.match(/^#([0-9a-f]{3,4}|[0-9a-f]{6}|[0-9a-f]{8})$/i);
   if (hex) {
+    const digits = hex[1].length <= 4 ? [...hex[1]].map((digit) => digit + digit).join("") : hex[1];
     return {
-      red: Number.parseInt(hex[1].slice(0, 2), 16),
-      green: Number.parseInt(hex[1].slice(2, 4), 16),
-      blue: Number.parseInt(hex[1].slice(4, 6), 16),
-      alpha: 1,
+      red: Number.parseInt(digits.slice(0, 2), 16),
+      green: Number.parseInt(digits.slice(2, 4), 16),
+      blue: Number.parseInt(digits.slice(4, 6), 16),
+      alpha: digits.length === 8 ? Number.parseInt(digits.slice(6, 8), 16) / 255 : 1,
     };
   }
 
-  const rgba = trimmed.match(
-    /^rgba?\(\s*([0-9.]+)\s*,\s*([0-9.]+)\s*,\s*([0-9.]+)(?:\s*,\s*([0-9.]+))?\s*\)$/i,
-  );
+  const rgba =
+    trimmed.match(
+      /^rgba?\(\s*([0-9.]+)\s*,\s*([0-9.]+)\s*,\s*([0-9.]+)(?:\s*,\s*([0-9.]+))?\s*\)$/,
+    ) ??
+    trimmed.match(/^rgba?\(\s*([\d.]+%?)\s+([\d.]+%?)\s+([\d.]+%?)(?:\s*\/\s*([\d.]+%?))?\s*\)$/);
   if (rgba) {
     return {
-      red: clampChannel(Number.parseFloat(rgba[1])),
-      green: clampChannel(Number.parseFloat(rgba[2])),
-      blue: clampChannel(Number.parseFloat(rgba[3])),
-      alpha: clampAlpha(rgba[4] != null ? Number.parseFloat(rgba[4]) : 1),
+      red: clampChannel(parseComponent(rgba[1], 255)),
+      green: clampChannel(parseComponent(rgba[2], 255)),
+      blue: clampChannel(parseComponent(rgba[3], 255)),
+      alpha: clampAlpha(rgba[4] != null ? parseComponent(rgba[4], 1) : 1),
     };
   }
 
   return null;
 }
 
+// Let the browser convert CSS Color 4 to sRGB without rasterizing a pixel.
+// Pixel readback would quantize alpha and lose RGB entirely for transparent colors.
+let colorContext: CanvasRenderingContext2D | null = null;
+
+function parseBrowserColor(value: string): ParsedColor | null {
+  if (
+    typeof document === "undefined" ||
+    typeof CSS === "undefined" ||
+    !CSS.supports("color", value) ||
+    /\bcurrentcolor\b|\bvar\s*\(/i.test(value)
+  )
+    return null;
+  try {
+    colorContext ??= document.createElement("canvas").getContext("2d");
+    if (!colorContext) return null;
+    // Invalid assignments leave fillStyle unchanged. Reset it on every call so
+    // invalid input cannot accidentally reuse the previous valid color.
+    colorContext.fillStyle = "#000000";
+    colorContext.fillStyle = `color(from ${value} srgb r g b / alpha)`;
+    return parseSrgbSerialization(colorContext.fillStyle);
+  } catch {
+    // Server rendering and DOM-only tests may not provide a canvas context.
+    return null;
+  }
+}
+
+function parseSrgbSerialization(
+  serialized: string | CanvasGradient | CanvasPattern,
+): ParsedColor | null {
+  if (typeof serialized !== "string") return null;
+  const match = serialized.match(/^color\(srgb ([^ ]+) ([^ ]+) ([^ /)]+)(?: \/ ([^)]+))?\)$/);
+  if (!match) return null;
+  const channels = match.slice(1, 4).map(Number);
+  const alpha = match[4] === undefined ? 1 : Number(match[4]);
+  if (!channels.every(Number.isFinite) || !Number.isFinite(alpha)) return null;
+  return {
+    red: clampChannel(channels[0] * 255),
+    green: clampChannel(channels[1] * 255),
+    blue: clampChannel(channels[2] * 255),
+    alpha: clampAlpha(alpha),
+  };
+}
+
+export function parseCssColor(value: string): ParsedColor | null {
+  const parsed = parseSerializedColor(value);
+  if (parsed && Object.values(parsed).every(Number.isFinite)) return parsed;
+  return parseBrowserColor(value.trim());
+}
+
 export function toColorPickerValue(value: string): string {
   const parsed = parseCssColor(value);
   if (!parsed) return "#000000";
diff --git a/packages/studio/src/components/editor/gradientValue.ts b/packages/studio/src/components/editor/gradientValue.ts
index 95f9c5a138..0f4f0bd11e 100644
--- a/packages/studio/src/components/editor/gradientValue.ts
+++ b/packages/studio/src/components/editor/gradientValue.ts
@@ -1,4 +1,5 @@
 import { roundToCenti } from "../../utils/rounding";
+import { parseCssColor } from "./colorValue";
 
 export type GradientKind = "linear" | "radial" | "conic";
 
@@ -384,8 +385,8 @@ function interpolateGradientStopColor(model: GradientModel, position: number): s
 
   const leftColor = left.color;
   const rightColor = right.color;
-  const leftParsed = leftColor ? parseColorString(leftColor) : null;
-  const rightParsed = rightColor ? parseColorString(rightColor) : null;
+  const leftParsed = leftColor ? parseCssColor(leftColor) : null;
+  const rightParsed = rightColor ? parseCssColor(rightColor) : null;
   if (!leftParsed || !rightParsed) return left.color;
 
   const ratio = (clampedPosition - left.position) / Math.max(1, right.position - left.position);
@@ -412,34 +413,3 @@ export function insertGradientStop(model: GradientModel, position: number): Grad
     stops: nextStops,
   };
 }
-
-function parseColorString(
-  value: string,
-): { red: number; green: number; blue: number; alpha: number } | null {
-  const trimmed = value.trim().toLowerCase();
-  if (trimmed === "transparent") {
-    return { red: 0, green: 0, blue: 0, alpha: 0 };
-  }
-
-  const hex = trimmed.match(/^#([0-9a-f]{6})$/i);
-  if (hex) {
-    return {
-      red: Number.parseInt(hex[1].slice(0, 2), 16),
-      green: Number.parseInt(hex[1].slice(2, 4), 16),
-      blue: Number.parseInt(hex[1].slice(4, 6), 16),
-      alpha: 1,
-    };
-  }
-
-  const rgba = trimmed.match(
-    /^rgba?\(\s*([0-9.]+)\s*,\s*([0-9.]+)\s*,\s*([0-9.]+)(?:\s*,\s*([0-9.]+))?\s*\)$/i,
-  );
-  if (!rgba) return null;
-
-  return {
-    red: Number.parseFloat(rgba[1]),
-    green: Number.parseFloat(rgba[2]),
-    blue: Number.parseFloat(rgba[3]),
-    alpha: rgba[4] != null ? Number.parseFloat(rgba[4]) : 1,
-  };
-}
diff --git a/packages/studio/tests/e2e/native-css-colors.mjs b/packages/studio/tests/e2e/native-css-colors.mjs
new file mode 100644
index 0000000000..734efe5c46
--- /dev/null
+++ b/packages/studio/tests/e2e/native-css-colors.mjs
@@ -0,0 +1,129 @@
+// Run with: node packages/studio/tests/e2e/native-css-colors.mjs
+// Uses real browser CSS parsing; happy-dom cannot verify these conversions.
+import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
+import { mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, join, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+import puppeteer from "puppeteer-core";
+import { resolveChromeExecutable } from "./chrome-executable.mjs";
+
+const output = mkdtempSync(join(tmpdir(), "native-css-colors-"));
+let browser;
+try {
+  execFileSync(
+    "bun",
+    [
+      "build",
+      "packages/studio/src/components/editor/colorValue.ts",
+      "packages/studio/src/components/editor/gradientValue.ts",
+      "--target",
+      "browser",
+      "--outdir",
+      output,
+    ],
+    { cwd: resolve(dirname(fileURLToPath(import.meta.url)), "../../../..") },
+  );
+  const moduleUrl = (name) =>
+    `data:text/javascript;base64,${readFileSync(join(output, `${name}.js`)).toString("base64")}`;
+  browser = await puppeteer.launch({
+    executablePath: resolveChromeExecutable(),
+    headless: true,
+    pipe: true,
+    args: ["--no-sandbox", "--disable-dev-shm-usage"],
+  });
+  const page = await browser.newPage();
+  const results = await page.evaluate(
+    async (colorUrl, gradientUrl) => {
+      const { parseCssColor, toColorPickerValue, mergeColorWithExistingAlpha } = await import(
+        colorUrl
+      );
+      const { parseGradient, insertGradientStop } = await import(gradientUrl);
+      const inputs = [
+        "white",
+        "rebeccapurple",
+        "#0f172acc",
+        "rgb(255 0 0 / 50%)",
+        "hsl(210 40% 50%)",
+        "color(srgb 0.4 0 0.6)",
+        "oklch(0.7 0.15 200)",
+        "oklab(0.6 0.1 0.1)",
+        "lab(100 0 0)",
+        "color(display-p3 1 0 0)",
+        "oklch(0.7 0.15 200 / 0)",
+        "color(srgb 0.4 0 0.6 / 0.001)",
+        "color-mix(in srgb, red 40%, blue)",
+        "notacolor",
+        "#12",
+        "currentcolor",
+        "none",
+        "var(--color)",
+      ];
+      const colors = inputs.map((input) => parseCssColor(input));
+      const gradient = parseGradient("linear-gradient(90deg, black 0%, white 100%)");
+      const alphaGradient = parseGradient("linear-gradient(90deg, #00000000 0%, #000000ff 100%)");
+      const element = document.createElement("span");
+      element.style.color = "oklch(0.7 0.15 200)";
+      document.body.append(element);
+      return {
+        colors,
+        picker: toColorPickerValue(getComputedStyle(element).color),
+        alpha: mergeColorWithExistingAlpha("#123456", "color(srgb 0.4 0 0.6 / 0.25)"),
+        gradient: insertGradientStop(gradient, 50).stops[1].color,
+        alphaGradient: insertGradientStop(alphaGradient, 50).stops[1].color,
+      };
+    },
+    moduleUrl("colorValue"),
+    moduleUrl("gradientValue"),
+  );
+  const expected = [
+    [255, 255, 255, 1],
+    [102, 51, 153, 1],
+    [15, 23, 42, 0.8],
+    [255, 0, 0, 0.5],
+    [77, 128, 179, 1],
+    [102, 0, 153, 1],
+    [0, 185, 195, 1],
+    [195, 96, 46, 1],
+    [255, 255, 255, 1],
+    [255, 0, 0, 1],
+    [0, 185, 195, 0],
+    [102, 0, 153, 0.001],
+    [102, 0, 153, 1],
+    null,
+    null,
+    null,
+    null,
+    null,
+  ];
+  for (const [index, channels] of expected.entries()) {
+    const actual = results.colors[index];
+    if (!channels) {
+      assert.equal(actual, null, `invalid color ${index}`);
+      continue;
+    }
+    assert.ok(actual, `color ${index} parsed`);
+    for (const [channel, value] of Object.entries({
+      red: channels[0],
+      green: channels[1],
+      blue: channels[2],
+    })) {
+      assert.ok(
+        Math.abs(actual[channel] - value) <= 1,
+        `color ${index} ${channel}: ${actual[channel]} vs ${value}`,
+      );
+    }
+    assert.ok(Math.abs(actual.alpha - channels[3]) < 0.000001, `color ${index} alpha`);
+  }
+  assert.equal(results.picker, "#00b9c3");
+  assert.equal(results.alpha, "rgba(18, 52, 86, 0.25)");
+  assert.equal(results.gradient, "#808080");
+  assert.equal(results.alphaGradient, "rgba(0, 0, 0, 0.5)");
+  console.log(
+    "Passed 18 native CSS color cases, computed-style picker, alpha preservation, and two gradient cases.",
+  );
+} finally {
+  await browser?.close();
+  rmSync(output, { recursive: true, force: true });
+}