Update

static/css/themes/no-theme.css

@@ -0,0 +1,66 @@
+:root[data-ui-theme="none"] {
+    --font-main: ui-monospace, monospace;
+    --desktop-bg: #ffffff;
+    --desktop-pattern: none;
+    --surface-window: transparent;
+    --surface-control: #f5f5f5;
+    --surface-input: #ffffff;
+    --surface-status: #ffffff;
+    --text-primary: #000000;
+    --title-bg: transparent;
+    --title-text: #000000;
+    --border-outer: #bdbdbd;
+    --border-input: #bdbdbd;
+    --border-muted: #d3d3d3;
+    --window-border-width: 1px;
+    --control-border-width: 1px;
+    --input-border-width: 1px;
+    --window-shadow: none;
+    --button-shadow: none;
+    --button-shadow-active: none;
+    --focus-ring: 0 0 0 1px #777777;
+    --card-bg: #ffffff;
+    --card-text: #000000;
+    --card-border: #bdbdbd;
+    --card-border-width: 1px;
+    --selected-outline: 1px dashed #000000;
+    --modal-overlay: rgba(0, 0, 0, 0.2);
+}
+
+:root[data-ui-theme="none"][data-theme="dark"] {
+    --desktop-bg: #111111;
+    --surface-window: transparent;
+    --surface-control: #232323;
+    --surface-input: #161616;
+    --surface-status: #161616;
+    --text-primary: #e8e8e8;
+    --title-bg: transparent;
+    --title-text: #e8e8e8;
+    --border-outer: #4a4a4a;
+    --border-input: #4a4a4a;
+    --border-muted: #3a3a3a;
+    --focus-ring: 0 0 0 1px #9a9a9a;
+    --card-bg: #161616;
+    --card-text: #e8e8e8;
+    --card-border: #4a4a4a;
+}
+
+:root[data-ui-theme="none"] body {
+    background-color: var(--desktop-bg);
+    background-image: none;
+}
+
+:root[data-ui-theme="none"] .title-bar-controls,
+:root[data-ui-theme="none"] .icon-btn img {
+    display: none;
+}
+
+:root[data-ui-theme="none"] .window,
+:root[data-ui-theme="none"] .preview-board,
+:root[data-ui-theme="none"] .voting-board {
+    border-style: dashed;
+}
+
+:root[data-ui-theme="none"] .preset-modal-overlay {
+    background: var(--modal-overlay);
+}