fix(window): restore clear Windows frame contours

- Apply stronger active and inactive renderer contours only on Windows.

- Keep native shadows disabled for main and Properties windows to prevent rectangular corner bleed.

- Lock platform configuration and maximized-frame invariants with regression tests.

scripts/window-frame.node-test.js

@@ -0,0 +1,79 @@
+import assert from 'node:assert/strict';
+import fs from 'node:fs';
+import test from 'node:test';
+
+const windowStyles = fs.readFileSync('src/index.css', 'utf8');
+const propertiesWindowSource = fs.readFileSync('src-tauri/src/properties_window.rs', 'utf8');
+const mainWindowSource = fs.readFileSync('src-tauri/src/lib.rs', 'utf8');
+const windowsConfiguration = JSON.parse(
+  fs.readFileSync('src-tauri/tauri.windows.conf.json', 'utf8')
+);
+
+const cssBlock = selector => {
+  const opening = `${selector} {`;
+  const start = windowStyles.indexOf(opening);
+  assert.notEqual(start, -1, `${selector} should exist`);
+  const end = windowStyles.indexOf('}', start + opening.length);
+  assert.notEqual(end, -1, `${selector} should have a closing brace`);
+  return windowStyles.slice(start, end + 1);
+};
+
+test('Windows native shadows remain disabled for the main and Properties windows', () => {
+  assert.deepEqual(
+    {
+      transparent: windowsConfiguration.app.windows[0].transparent,
+      decorations: windowsConfiguration.app.windows[0].decorations,
+      shadow: windowsConfiguration.app.windows[0].shadow,
+    },
+    { transparent: true, decorations: false, shadow: false }
+  );
+  assert.match(
+    mainWindowSource,
+    /let main_window_config = app\s*\.config\(\)\s*\.app\s*\.windows[\s\S]*?\.find\(\|window\| window\.label == "main"\)/
+  );
+  assert.match(
+    mainWindowSource,
+    /WebviewWindowBuilder::from_config\(\s*app\.handle\(\),\s*&main_window_config,\s*\)/
+  );
+  assert.match(
+    propertiesWindowSource,
+    /#\[cfg\(target_os = "windows"\)\]\s*let builder = builder\.transparent\(true\)\.shadow\(false\);/
+  );
+});
+
+test('Windows selects stronger renderer-owned contours for every theme', () => {
+  const expectedTokens = [
+    [':root', '220 12% 30% / 0.60', '220 10% 30% / 0.18'],
+    ['.theme-light', '220 12% 30% / 0.60', '220 10% 30% / 0.18'],
+    ['.theme-dark', '0 0% 100% / 0.35', '0 0% 100% / 0.14'],
+    ['.theme-dracula', '228 14% 84% / 0.45', '228 14% 84% / 0.18'],
+    ['.theme-nord', '218 27% 88% / 0.45', '218 27% 88% / 0.18'],
+  ];
+
+  for (const [selector, active, inactive] of expectedTokens) {
+    const block = cssBlock(selector);
+    assert.match(block, new RegExp(`--window-frame-windows-active: ${active.replace('.', '\\.')}\\s*;`));
+    assert.match(block, new RegExp(`--window-frame-windows-inactive: ${inactive.replace('.', '\\.')}\\s*;`));
+  }
+
+  const windowsBlock = cssBlock('html[data-platform="windows"]');
+  assert.match(
+    windowsBlock,
+    /--window-frame-active:\s*var\(--window-frame-windows-active\);/
+  );
+  assert.match(
+    windowsBlock,
+    /--window-frame-inactive:\s*var\(--window-frame-windows-inactive\);/
+  );
+});
+
+test('maximized Windows shells remain square and borderless', () => {
+  assert.match(
+    windowStyles,
+    /html\[data-platform="windows"\] :is\(\.app-shell, \.properties-window-shell\)\[data-window-maximized="true"\] \{\s*border-color:\s*transparent;/
+  );
+  assert.match(
+    windowStyles,
+    /html\[data-platform="linux"\] :is\(\.app-shell, \.properties-window-shell\),\s*html\[data-platform="windows"\] :is\(\.app-shell, \.properties-window-shell\)\[data-window-maximized="true"\] \{\s*border-radius:\s*0;/
+  );
+});

src/index.css

@@ -29,6 +29,8 @@
   --shadow-color: 220 10% 20% / 0.1;
   --window-frame-active: 220 12% 30% / 0.22;
   --window-frame-inactive: 220 10% 30% / 0.08;
+  --window-frame-windows-active: 220 12% 30% / 0.60;
+  --window-frame-windows-inactive: 220 10% 30% / 0.18;
   --sidebar-shell-bg: 0 0% 92%;
   --sidebar-panel-bg: 0 0% 96%;
   --workspace-bg: 0 0% 98%;
@@ -77,6 +79,8 @@
   --shadow-color: 220 10% 20% / 0.1;
   --window-frame-active: 220 12% 30% / 0.22;
   --window-frame-inactive: 220 10% 30% / 0.08;
+  --window-frame-windows-active: 220 12% 30% / 0.60;
+  --window-frame-windows-inactive: 220 10% 30% / 0.18;
   --sidebar-shell-bg: 0 0% 92%;
   --sidebar-panel-bg: 0 0% 96%;
   --workspace-bg: 0 0% 98%;
@@ -109,6 +113,8 @@
   --shadow-color: 0 0% 0% / 0.30;
   --window-frame-active: 0 0% 100% / 0.14;
   --window-frame-inactive: 0 0% 100% / 0.06;
+  --window-frame-windows-active: 0 0% 100% / 0.35;
+  --window-frame-windows-inactive: 0 0% 100% / 0.14;
   --status-completed: 136 62% 48%;
   --status-paused: 0 0% 56%;
   --status-downloading: 211 100% 56%;
@@ -158,6 +164,8 @@
   --shadow-color: 231 20% 8% / 0.35;
   --window-frame-active: 228 14% 84% / 0.18;
   --window-frame-inactive: 228 14% 84% / 0.08;
+  --window-frame-windows-active: 228 14% 84% / 0.45;
+  --window-frame-windows-inactive: 228 14% 84% / 0.18;
   --status-completed: 135 94% 65%;
   --status-paused: 65 92% 76%;
   --status-downloading: 191 97% 77%;
@@ -207,6 +215,8 @@
   --shadow-color: 220 25% 10% / 0.34;
   --window-frame-active: 218 27% 88% / 0.18;
   --window-frame-inactive: 218 27% 88% / 0.08;
+  --window-frame-windows-active: 218 27% 88% / 0.45;
+  --window-frame-windows-inactive: 218 27% 88% / 0.18;
   --status-completed: 92 28% 65%;
   --status-paused: 40 71% 73%;
   --status-downloading: 193 43% 67%;
@@ -232,6 +242,14 @@
   --add-shadow: 220 28% 10% / 0.30;
 }
 
+/* Windows cannot safely combine Tao's native undecorated shadow with this
+   per-pixel-transparent rounded surface. Select the stronger renderer-owned
+   contour tokens without increasing the macOS or Linux frame contrast. */
+html[data-platform="windows"] {
+  --window-frame-active: var(--window-frame-windows-active);
+  --window-frame-inactive: var(--window-frame-windows-inactive);
+}
+
 @theme {
   --color-sidebar-bg: hsl(var(--sidebar-bg));
   --color-sidebar-glass: hsl(var(--sidebar-glass));