diff --git a/alert.go b/alert.go
index 2b5f116..8d78108 100644
--- a/alert.go
+++ b/alert.go
@@ -43,8 +43,10 @@ func severityLook(k theme.Tokens, s Severity) (ui.Color, *ui.SVG) {
 		return k.Warning, icons.Must("triangle-alert")
 	case SeverityError:
 		return k.Danger, icons.Must("circle-x")
+	case SeverityInfo:
+		return k.Info, icons.Must("info")
 	}
-	return k.Info, icons.Must("info")
+	panic(fmt.Sprintf("mujica: unknown Severity %d", int(s)))
 }
 
 // AlertOptions configure an Alert.
@@ -66,9 +68,7 @@ type AlertResult struct {
 	Closed bool
 }
 
-// Alert shows an inline message marked by color, icon and accessible name.
-// A non-nil open adds a dismiss button that sets *open to false; nothing
-// shows while *open is false.
+// Alert shows an inline message; a non-nil open adds a dismiss button that clears it.
 func Alert(c *ui.Context, open *bool, message string, opts AlertOptions) AlertResult {
 	if message == "" {
 		panic("mujica: Alert needs a message")
diff --git a/docs/components/093-progress.md b/docs/components/093-progress.md
index 8609972..36caa84 100644
--- a/docs/components/093-progress.md
+++ b/docs/components/093-progress.md
@@ -27,18 +27,18 @@ mujica.Meter(c, 93, mujica.MeterOptions{
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
 | `value` | `float64` | 必填 | 0 到 1；超出或 NaN 时 panic（不确定模式忽略）。 |
-| `Shape` | `ProgressShape` | `ProgressLinear` | `ProgressLinear` 或 `ProgressRing`。 |
+| `Shape` | `ProgressShape` | `ProgressLinear` | `ProgressLinear` 或 `ProgressRing`；其他值 panic。 |
 | `Indeterminate` | `bool` | `false` | 未知长度的进度。 |
 | `Label` | `string` | `""` | 显示在旁边并作为无障碍名称；为空时名称为“Loading”。 |
 | `ShowValue` | `bool` | `false` | 显示百分比。 |
-| `Size` | `float32` | 环形 48、线形填满 | 环形直径或线形宽度；负数 panic。 |
+| `Size` | `float32` | 环形 48、线形填满 | 环形直径或线形宽度；负数、NaN 或无穷 panic。 |
 
 `MeterOptions`：
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
 | `value` | `float64` | 必填 | 须在范围内，否则 panic。 |
-| `Min`, `Max` | `float64` | 0, 1（两者都为 0 时） | 范围；`Max <= Min` panic。 |
+| `Min`, `Max` | `float64` | 0, 1（两者都为 0 时） | 范围；非有限值或 `Max <= Min` panic。 |
 | `Levels` | `*ui.MeterLevels` | `nil` | 阈值：达到 `Warning` 为偏高、达到 `Critical` 为严重；`Critical < Warning` 时低值为坏（如电量）。须在范围内。 |
 | `Label` | `string` | `""` | 名称。 |
 | `ShowValue` | `bool` | `false` | 显示“值 / 最大值”。 |
@@ -47,7 +47,7 @@ mujica.Meter(c, 93, mujica.MeterOptions{
 ## 状态
 
 - 确定进度变化时以 120 ms 过渡，减少动画时直接跳到新值。
-- 不确定进度只在绘制时移动（只重绘、不重建视图）；减少动画时显示静态填充和“In progress”文字。
+- 不确定进度只在绘制时移动（只重绘、不重建视图）；减少动画时显示满格静态填充（对比度不低于 3:1）和“In progress”文字；切换到减少动画时进行中的过渡直接跳到目标值。
 - 计量条按级别使用 Success / Warning / Danger 颜色，同时显示“Normal / High / Critical / Low”文字与阈值刻度，并把级别写入无障碍名称。
 
 ## 事件
diff --git a/docs/components/094-spinner.md b/docs/components/094-spinner.md
index 06d612f..f4698c3 100644
--- a/docs/components/094-spinner.md
+++ b/docs/components/094-spinner.md
@@ -16,7 +16,7 @@ mujica.Spinner(c, mujica.SpinnerOptions{Size: 20, Label: "Syncing", ShowLabel: t
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
-| `Size` | `float32` | 16 | 标记边长（DIP）。 |
+| `Size` | `float32` | 16 | 标记边长（DIP）；负数、NaN 或无穷 panic。 |
 | `Label` | `string` | 内置“Loading / 加载中” | 无障碍名称；`ShowLabel` 时也显示在旁边。 |
 | `ShowLabel` | `bool` | `false` | 在标记旁显示说明。 |
 | `Color` | `ui.Color` | `AccentText` | 标记颜色。 |
diff --git a/docs/components/095-skeleton.md b/docs/components/095-skeleton.md
index 4e7e7e1..188319f 100644
--- a/docs/components/095-skeleton.md
+++ b/docs/components/095-skeleton.md
@@ -26,7 +26,7 @@ ui.Row(c).Gap(12).Children(func() {
 | `Height` | `float32` | 当前密度控件高度 | 矩形高度；文字形状由行数决定（每行 21 DIP）。 |
 | `Lines` | `int` | 1 | 文字行数，多行时最后一行为 60% 宽。 |
 
-负值 panic。
+负值、NaN、无穷或未知形状 panic。文字行高随系统文本缩放。
 
 ## 状态
 
diff --git a/empty_state.go b/empty_state.go
index 67ca961..2951801 100644
--- a/empty_state.go
+++ b/empty_state.go
@@ -76,7 +76,7 @@ func EmptyState(c *ui.Context, opts EmptyStateOptions) EmptyStateResult {
 		if !opts.NoIcon {
 			ui.Icon(c, icon).Size(32, 32).TextColor(k.TextMuted).Margin(0, 0, u*2, 0)
 		}
-		ui.Text(c, title).Font(theme.SerifFont).FontSize(theme.H3Size).TextColor(k.Text).TextAlign(ui.Center)
+		ui.Text(c, title).Font(theme.SerifFont).FontSize(FontSize(c, theme.H3Size)).TextColor(k.Text).TextAlign(ui.Center)
 		ui.Text(c, desc).TextColor(k.TextMuted).TextAlign(ui.Center).MaxWidth(360).LineHeight(theme.LineHeight)
 		if opts.Action != "" {
 			ui.Box(c).Margin(u*2, 0, 0, 0).Children(func() {
diff --git a/feedback_review_test.go b/feedback_review_test.go
new file mode 100644
index 0000000..d332dad
--- /dev/null
+++ b/feedback_review_test.go
@@ -0,0 +1,84 @@
+package mujica
+
+import (
+	"math"
+	"testing"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
+)
+
+func TestFeedbackTextFollowsTextScale(t *testing.T) {
+	items := []Notification{{ID: "n", Title: "Backup complete", Read: true}, {ID: "u", Title: "Unread one"}}
+	var empty, result float32
+	tt := ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{})
+		ui.Column(c).Children(func() {
+			Progress(c, 0.5, ProgressOptions{ShowValue: true})
+			empty = EmptyState(c, EmptyStateOptions{Title: "Empty title", Description: "Short", NoIcon: true}).Element.Bounds().H
+			result = Result(c, ResultOptions{Title: "Result title"}).Element.Bounds().H
+			StatusIndicator(c, StatusSuccess, StatusIndicatorOptions{})
+			NotificationCenter(c, &items, NotificationCenterOptions{})
+		})
+	}, 900, 2400)
+	tt.Frame()
+	empty1, result1 := empty, result
+	tt.SetPreferences(ui.Preferences{TextScale: 2})
+	tt.Frame() // Bounds report the previous layout
+	for text, min := range map[string]float32{
+		"50%":      theme.CaptionSize * 2,
+		"Healthy":  theme.BodySize * 2,
+		"1 unread": theme.CaptionSize * 2,
+	} {
+		if r, ok := tt.Find(text); !ok || r.H < min {
+			t.Errorf("%q at 200%%: %v %v, want height >= %v", text, r, ok, min)
+		}
+	}
+	// Titles are found only through their labeled groups: the groups must grow by the titles too.
+	if grow := empty - empty1; grow < theme.BodySize*theme.LineHeight+theme.H3Size {
+		t.Errorf("EmptyState grew %v at 200%%; its title did not scale", grow)
+	}
+	if grow := result - result1; grow < theme.H2Size {
+		t.Errorf("Result grew %v at 200%%; its title did not scale", grow)
+	}
+}
+
+func TestFeedbackRejectsInvalidInput(t *testing.T) {
+	nan, inf := math.NaN(), math.Inf(1)
+	for name, f := range map[string]func(c *ui.Context){
+		"progress shape":       func(c *ui.Context) { Progress(c, 0.5, ProgressOptions{Shape: 7}) },
+		"progress NaN size":    func(c *ui.Context) { Progress(c, 0.5, ProgressOptions{Size: float32(nan)}) },
+		"meter infinite range": func(c *ui.Context) { Meter(c, 1, MeterOptions{Max: inf}) },
+		"meter NaN min":        func(c *ui.Context) { Meter(c, 1, MeterOptions{Min: nan, Max: 2}) },
+		"meter NaN threshold": func(c *ui.Context) {
+			Meter(c, 1, MeterOptions{Max: 2, Levels: &ui.MeterLevels{Warning: nan, Critical: 2}})
+		},
+		"skeleton shape":         func(c *ui.Context) { Skeleton(c, SkeletonOptions{Shape: 5}) },
+		"skeleton NaN width":     func(c *ui.Context) { Skeleton(c, SkeletonOptions{Width: float32(nan)}) },
+		"spinner negative size":  func(c *ui.Context) { Spinner(c, SpinnerOptions{Size: -4}) },
+		"status unknown labeled": func(c *ui.Context) { StatusIndicator(c, 42, StatusIndicatorOptions{Label: "Custom"}) },
+		"alert severity":         func(c *ui.Context) { Alert(c, nil, "x", AlertOptions{Severity: 9}) },
+		"toast severity":         func(c *ui.Context) { ShowToast(c, ToastMessage{Message: "x", Severity: -1}) },
+	} {
+		func() {
+			defer func() {
+				if recover() == nil {
+					t.Errorf("%s: no panic", name)
+				}
+			}()
+			ui.NewTester(func(c *ui.Context) { Use(c, Settings{}); f(c) }, 300, 200)
+		}()
+	}
+}
+
+func TestNotificationTitleOnlyHitHeight(t *testing.T) {
+	items := []Notification{{ID: "n", Title: "Backup complete", Read: true}}
+	tt := ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{})
+		NotificationCenter(c, &items, NotificationCenterOptions{})
+	}, 600, 400)
+	if r, ok := tt.Find("Backup complete"); !ok || r.H < theme.MinHitSize {
+		t.Fatalf("title-only notification hit box %v %v", r, ok)
+	}
+}
diff --git a/loading_overlay.go b/loading_overlay.go
index 6f8ba0d..5e826b4 100644
--- a/loading_overlay.go
+++ b/loading_overlay.go
@@ -25,9 +25,7 @@ type LoadingOverlayResult struct {
 	Canceled bool
 }
 
-// LoadingOverlay builds content and, while loading, covers it with a
-// spinner and label. Covered content takes no pointer, keys or focus;
-// the rest of the window stays usable. Focus inside moves to the overlay.
+// LoadingOverlay covers content while loading, blocking input to that region only.
 func LoadingOverlay(c *ui.Context, loading bool, opts LoadingOverlayOptions, content func()) LoadingOverlayResult {
 	if content == nil {
 		panic("mujica: LoadingOverlay needs content")
diff --git a/notification_center.go b/notification_center.go
index 19a4f93..f712d4d 100644
--- a/notification_center.go
+++ b/notification_center.go
@@ -44,9 +44,7 @@ type NotificationCenterResult struct {
 	ClearedAll    bool
 }
 
-// NotificationCenter lists *items and edits them in place: read, unread,
-// remove, clear. The list is one Tab stop; arrows move among its buttons
-// and Delete removes the focused notification.
+// NotificationCenter lists *items and edits them in place: read, unread, remove, clear.
 func NotificationCenter(c *ui.Context, items *[]Notification, opts NotificationCenterOptions) NotificationCenterResult {
 	if items == nil {
 		panic("mujica: NotificationCenter needs items")
@@ -70,9 +68,9 @@ func NotificationCenter(c *ui.Context, items *[]Notification, opts NotificationC
 		Role(ui.RoleGroup).Label(title).Clip()
 	panel.Children(func() {
 		ui.Row(c).AlignItems(ui.Center).Gap(u*2).Padding(u*3, u*3, u*3, u*4).Children(func() {
-			ui.Text(c, title).Font(theme.SerifFont).FontSize(theme.H3Size).TextColor(k.Text)
+			ui.Text(c, title).Font(theme.SerifFont).FontSize(FontSize(c, theme.H3Size)).TextColor(k.Text)
 			if unread > 0 {
-				ui.Text(c, fmt.Sprintf(msg(c, "notification_center.unread"), unread)).FontSize(theme.CaptionSize).TextColor(k.AccentText)
+				ui.Text(c, fmt.Sprintf(msg(c, "notification_center.unread"), unread)).FontSize(FontSize(c, theme.CaptionSize)).TextColor(k.AccentText)
 			}
 			ui.Spacer(c)
 			if Button(c, msg(c, "notification_center.mark_all_read"), ButtonOptions{Variant: Ghost, Disabled: unread == 0}).Clicked() {
@@ -135,7 +133,7 @@ func notificationRow(c *ui.Context, k theme.Tokens, u float32, n *Notification,
 				p.FillPath(internal.Diamond(r.X+r.W/2, r.Y+r.H/2, 8), k.AccentText)
 			}
 		})
-		open := ui.ButtonBase(c).Grow(1).Shrink(1).Column().AlignItems(ui.Start).Justify(ui.Start).Gap(u).
+		open := ui.ButtonBase(c).MinHeight(theme.MinHitSize).Grow(1).Shrink(1).Column().AlignItems(ui.Start).Justify(ui.Start).Gap(u).
 			Radius(theme.ControlRadius).Label(name)
 		internal.Ring(open, k.Focus, theme.ControlRadius)
 		open.Children(func() {
@@ -145,7 +143,7 @@ func notificationRow(c *ui.Context, k theme.Tokens, u float32, n *Notification,
 					t.Bold()
 				}
 				if n.Time != "" {
-					ui.Text(c, n.Time).FontSize(theme.CaptionSize).TextColor(k.TextMuted).SingleLine()
+					ui.Text(c, n.Time).FontSize(FontSize(c, theme.CaptionSize)).TextColor(k.TextMuted).SingleLine()
 				}
 			})
 			if n.Body != "" {
diff --git a/progress.go b/progress.go
index 85d09dc..08f60cd 100644
--- a/progress.go
+++ b/progress.go
@@ -31,14 +31,16 @@ type ProgressOptions struct {
 	Size float32
 }
 
-// Progress shows value, from 0 to 1, of work done. It panics outside that range.
-// Indeterminate indicators move only while painted and hold still under reduced motion.
+// Progress shows work done, value 0 to 1; indeterminate ones hold still under reduced motion.
 func Progress(c *ui.Context, value float64, opts ProgressOptions) *ui.Element {
+	if opts.Shape != ProgressLinear && opts.Shape != ProgressRing {
+		panic(fmt.Sprintf("mujica: unknown ProgressShape %d", int(opts.Shape)))
+	}
 	if !opts.Indeterminate && (math.IsNaN(value) || value < 0 || value > 1) {
 		panic(fmt.Sprintf("mujica: Progress value %v outside 0..1", value))
 	}
-	if opts.Size < 0 {
-		panic("mujica: negative Progress Size")
+	if !(opts.Size >= 0) || math.IsInf(float64(opts.Size), 1) {
+		panic(fmt.Sprintf("mujica: Progress Size %v invalid", opts.Size))
 	}
 	k := Tokens(c)
 	u := Density(c).Unit()
@@ -71,12 +73,12 @@ func Progress(c *ui.Context, value float64, opts ProgressOptions) *ui.Element {
 		if opts.Label != "" || caption != "" {
 			ui.Row(c).Gap(u * 2).Children(func() {
 				ui.Text(c, opts.Label).TextColor(k.Text).Grow(1).Shrink(1)
-				ui.Text(c, caption).TextColor(k.TextMuted).FontSize(theme.CaptionSize).FontFeatures("tnum").SingleLine()
+				ui.Text(c, caption).TextColor(k.TextMuted).FontSize(FontSize(c, theme.CaptionSize)).FontFeatures("tnum").SingleLine()
 			})
 		}
 		bar := ui.Progress(c, acc).Label(name).FillWidth().Height(u * 1.5).Radius(theme.ControlRadius).Background(k.Border)
 		shown := float32(value)
-		if !opts.Indeterminate {
+		if !opts.Indeterminate && !still {
 			shown = bar.Animate("progress.value", shown, theme.StateDuration)
 		}
 		bar.Draw(func(p *ui.Painter, r ui.Rect) {
@@ -84,7 +86,7 @@ func Progress(c *ui.Context, value float64, opts ProgressOptions) *ui.Element {
 			case !opts.Indeterminate:
 				p.Fill(ui.Rect{X: r.X, Y: r.Y, W: r.W * shown, H: r.H}, k.AccentText, theme.ControlRadius)
 			case still:
-				p.Fill(r, k.AccentText.Alpha(0.4), theme.ControlRadius)
+				p.Fill(r, k.AccentText, theme.ControlRadius)
 			default:
 				p.AnimationFrame()
 				phase := float32(p.Now().UnixMilli()%1400) / 1400
@@ -108,7 +110,7 @@ func progressRing(c *ui.Context, k theme.Tokens, u float32, acc float64, name, c
 	row.Children(func() {
 		ring := ui.Progress(c, acc).Label(name).Size(d, d).Radius(0).Background(ui.Transparent)
 		shown := float32(acc)
-		if !opts.Indeterminate {
+		if !opts.Indeterminate && !still {
 			shown = ring.Animate("progress.value", shown, theme.StateDuration)
 		}
 		stroke := max(3, d/10)
@@ -123,7 +125,7 @@ func progressRing(c *ui.Context, k theme.Tokens, u float32, acc float64, name, c
 					p.StrokePath(progressArc(p, cx, cy, rad, 0, shown), stroke, k.AccentText)
 				}
 			case still:
-				p.StrokePath(&track, stroke, k.AccentText.Alpha(0.4))
+				p.StrokePath(&track, stroke, k.AccentText)
 			default:
 				p.AnimationFrame()
 				start := float32(p.Now().UnixMilli()%1200) / 1200
@@ -132,7 +134,7 @@ func progressRing(c *ui.Context, k theme.Tokens, u float32, acc float64, name, c
 		})
 		if caption != "" && d >= 44 && !opts.Indeterminate {
 			ring.Children(func() {
-				ui.Text(c, caption).FontSize(theme.CaptionSize).FontFeatures("tnum").TextColor(k.Text)
+				ui.Text(c, caption).FontSize(FontSize(c, theme.CaptionSize)).FontFeatures("tnum").TextColor(k.Text)
 			})
 			ring.Center()
 		}
@@ -142,7 +144,7 @@ func progressRing(c *ui.Context, k theme.Tokens, u float32, acc float64, name, c
 					ui.Text(c, opts.Label).TextColor(k.Text)
 				}
 				if caption != "" && (d < 44 || opts.Indeterminate) {
-					ui.Text(c, caption).TextColor(k.TextMuted).FontSize(theme.CaptionSize)
+					ui.Text(c, caption).TextColor(k.TextMuted).FontSize(FontSize(c, theme.CaptionSize))
 				}
 			})
 		}
@@ -171,8 +173,7 @@ func progressArc(pt *ui.Painter, cx, cy, r float32, a, b float32) *ui.Path {
 type MeterOptions struct {
 	// Min and Max bound the value; both zero mean 0 to 1.
 	Min, Max float64
-	// Levels mark the value High from Warning and Critical from Critical;
-	// Critical below Warning flags low values instead. Nil marks none.
+	// Levels are the High and Critical thresholds; Critical below Warning flags low values.
 	Levels    *ui.MeterLevels
 	Label     string
 	ShowValue bool
@@ -195,21 +196,20 @@ func meterLevel(v float64, l *ui.MeterLevels) int {
 	return 0
 }
 
-// Meter shows a level within a range, as disk use. Thresholds show as
-// ticks and the level as a word as well as a color. It panics on a value outside the range.
+// Meter shows a level within a range with threshold ticks and a level word, not color alone.
 func Meter(c *ui.Context, value float64, opts MeterOptions) *ui.Element {
 	lo, hi := opts.Min, opts.Max
 	if lo == 0 && hi == 0 {
 		hi = 1
 	}
-	if !(hi > lo) {
+	if !finite(lo) || !finite(hi) || !(hi > lo) {
 		panic(fmt.Sprintf("mujica: Meter range %v..%v is empty", lo, hi))
 	}
 	if math.IsNaN(value) || value < lo || value > hi {
 		panic(fmt.Sprintf("mujica: Meter value %v outside %v..%v", value, lo, hi))
 	}
-	if l := opts.Levels; l != nil && (l.Warning < lo || l.Warning > hi || l.Critical < lo || l.Critical > hi) {
-		panic("mujica: Meter levels outside the range")
+	if l := opts.Levels; l != nil && !(l.Warning >= lo && l.Warning <= hi && l.Critical >= lo && l.Critical <= hi) {
+		panic(fmt.Sprintf("mujica: Meter levels %+v outside %v..%v", *l, lo, hi))
 	}
 	k := Tokens(c)
 	u := Density(c).Unit()
@@ -246,7 +246,7 @@ func Meter(c *ui.Context, value float64, opts MeterOptions) *ui.Element {
 		if opts.Label != "" || caption != "" {
 			ui.Row(c).Gap(u * 2).Children(func() {
 				ui.Text(c, opts.Label).TextColor(k.Text).Grow(1).Shrink(1)
-				ui.Text(c, caption).TextColor(k.TextMuted).FontSize(theme.CaptionSize).FontFeatures("tnum").SingleLine()
+				ui.Text(c, caption).TextColor(k.TextMuted).FontSize(FontSize(c, theme.CaptionSize)).FontFeatures("tnum").SingleLine()
 			})
 		}
 		name := opts.Label
@@ -270,3 +270,5 @@ func Meter(c *ui.Context, value float64, opts MeterOptions) *ui.Element {
 	})
 	return col
 }
+
+func finite(v float64) bool { return !math.IsNaN(v) && !math.IsInf(v, 0) }
diff --git a/progress_test.go b/progress_test.go
index 78c5bdf..4016a1e 100644
--- a/progress_test.go
+++ b/progress_test.go
@@ -5,8 +5,54 @@ import (
 	"testing"
 
 	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
 )
 
+func TestProgressReducedMotionJumpsMidTransition(t *testing.T) {
+	v := 0.0
+	var bar ui.Rect
+	tt := ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{Mode: Light})
+		ui.Column(c).Width(300).Children(func() {
+			bar = Progress(c, v, ProgressOptions{}).Bounds()
+		})
+	}, 400, 100)
+	v = 1
+	tt.Frame()
+	tt.SetPreferences(ui.Preferences{ReduceMotion: true, TextScale: 1})
+	if got, want := progressPixel(tt, bar.X+bar.W*0.95, bar.Y+bar.H/2), theme.Light().AccentText; got != want {
+		t.Fatalf("fill at 95%% is %v, want %v at once", got, want)
+	}
+}
+
+func progressPixel(tt *ui.Tester, x, y float32) ui.Color {
+	r, g, b, _ := tt.Image().At(int(x), int(y)).RGBA()
+	return ui.RGB(uint8(r>>8), uint8(g>>8), uint8(b>>8))
+}
+
+func TestProgressStaticFillContrast(t *testing.T) {
+	for _, m := range []Mode{Light, Dark} {
+		var bar ui.Rect
+		var k theme.Tokens
+		tt := ui.NewTester(func(c *ui.Context) {
+			Use(c, Settings{Mode: m})
+			k = Tokens(c)
+			ui.Column(c).Width(300).Children(func() {
+				bar = Progress(c, 0, ProgressOptions{Indeterminate: true}).Bounds()
+			})
+		}, 400, 100)
+		tt.SetPreferences(ui.Preferences{ReduceMotion: true, TextScale: 1})
+		tt.Frame()                                              // Bounds report the previous layout
+		fill := progressPixel(tt, bar.X+bar.W/2, bar.Y+bar.H-3) // the bar is the last row
+		for _, against := range []ui.Color{k.Border, k.Background} {
+			if cr := theme.Contrast(fill, against); cr < 3 {
+				t.Errorf("%v: static fill %v vs %v is %.2f:1", m, fill, against, cr)
+			}
+		}
+	}
+}
+
 func TestProgressValueText(t *testing.T) {
 	v := 0.424
 	tt := ui.NewTester(func(c *ui.Context) {
diff --git a/result.go b/result.go
index 70814d0..537cc19 100644
--- a/result.go
+++ b/result.go
@@ -38,8 +38,7 @@ type ResultResult struct {
 	Action int
 }
 
-// Result reports the outcome of a finished task and offers next steps.
-// It only reports the chosen step; the caller navigates.
+// Result shows a task outcome and reports the chosen next step; the caller navigates.
 func Result(c *ui.Context, opts ResultOptions) ResultResult {
 	k := Tokens(c)
 	u := Density(c).Unit()
@@ -61,7 +60,7 @@ func Result(c *ui.Context, opts ResultOptions) ResultResult {
 	res.Element = ui.Column(c).FillWidth().AlignItems(ui.Center).Gap(u*3).Padding(u*10, u*6).Role(ui.RoleGroup).Label(title)
 	res.Element.Children(func() {
 		ui.Icon(c, icon).Size(48, 48).TextColor(tone)
-		ui.Text(c, title).Font(theme.SerifFont).FontSize(theme.H2Size).TextColor(k.Text).TextAlign(ui.Center)
+		ui.Text(c, title).Font(theme.SerifFont).FontSize(FontSize(c, theme.H2Size)).TextColor(k.Text).TextAlign(ui.Center)
 		if opts.Description != "" {
 			ui.Text(c, opts.Description).TextColor(k.TextMuted).TextAlign(ui.Center).MaxWidth(420).LineHeight(theme.LineHeight)
 		}
diff --git a/skeleton.go b/skeleton.go
index eefa1b5..3c4eb04 100644
--- a/skeleton.go
+++ b/skeleton.go
@@ -1,6 +1,7 @@
 package mujica
 
 import (
+	"fmt"
 	"math"
 
 	"github.com/egoist/mygo/ui"
@@ -28,11 +29,13 @@ type SkeletonOptions struct {
 	Lines int
 }
 
-// Skeleton stands in for content that is loading. It pulses while painted
-// and shows a static fill under reduced motion.
+// Skeleton stands in for loading content; it pulses while painted, static under reduced motion.
 func Skeleton(c *ui.Context, opts SkeletonOptions) *ui.Element {
-	if opts.Width < 0 || opts.Height < 0 || opts.Lines < 0 {
-		panic("mujica: negative Skeleton size")
+	if opts.Shape != SkeletonText && opts.Shape != SkeletonCircle && opts.Shape != SkeletonRect {
+		panic(fmt.Sprintf("mujica: unknown SkeletonShape %d", int(opts.Shape)))
+	}
+	if !(opts.Width >= 0) || !(opts.Height >= 0) || opts.Lines < 0 || math.IsInf(float64(opts.Width+opts.Height), 1) {
+		panic(fmt.Sprintf("mujica: Skeleton size %vx%v, %d lines invalid", opts.Width, opts.Height, opts.Lines))
 	}
 	k := Tokens(c)
 	still := c.Preferences().ReduceMotion
@@ -70,9 +73,10 @@ func Skeleton(c *ui.Context, opts SkeletonOptions) *ui.Element {
 		e.Height(h).Draw(func(p *ui.Painter, r ui.Rect) { paint(p, r, theme.CardRadius) })
 	default:
 		lines := max(opts.Lines, 1)
-		line := theme.BodySize * theme.LineHeight
+		size := FontSize(c, theme.BodySize)
+		line := size * theme.LineHeight
 		e.Height(line * float32(lines)).Draw(func(p *ui.Painter, r ui.Rect) {
-			bar := theme.BodySize * 0.8
+			bar := size * 0.8
 			for i := range lines {
 				w := r.W
 				if lines > 1 && i == lines-1 {
diff --git a/spinner.go b/spinner.go
index 2f1e9dd..280f968 100644
--- a/spinner.go
+++ b/spinner.go
@@ -1,6 +1,7 @@
 package mujica
 
 import (
+	"fmt"
 	"math"
 
 	"github.com/egoist/mygo/ui"
@@ -18,12 +19,14 @@ type SpinnerOptions struct {
 	Color ui.Color
 }
 
-// Spinner draws four diamonds turning around a center while it shows.
-// It repaints only while painted: hidden, it stops. Reduced motion holds it still.
+// Spinner turns four diamonds only while painted; hidden or under reduced motion it stops.
 func Spinner(c *ui.Context, opts SpinnerOptions) *ui.Element {
+	if !(opts.Size >= 0) || math.IsInf(float64(opts.Size), 1) {
+		panic(fmt.Sprintf("mujica: Spinner Size %v invalid", opts.Size))
+	}
 	k := Tokens(c)
 	size := opts.Size
-	if size <= 0 {
+	if size == 0 {
 		size = 16
 	}
 	label := opts.Label
diff --git a/status_indicator.go b/status_indicator.go
index 045c642..1ebcf5a 100644
--- a/status_indicator.go
+++ b/status_indicator.go
@@ -44,11 +44,12 @@ type StatusIndicatorOptions struct {
 
 // StatusIndicator shows a status by its own shape and a word, never by color alone.
 func StatusIndicator(c *ui.Context, status Status, opts StatusIndicatorOptions) *ui.Element {
+	key := "status_indicator." + status.String() // panics on an unknown Status
 	k := Tokens(c)
 	u := Density(c).Unit()
 	label := opts.Label
 	if label == "" {
-		label = msg(c, "status_indicator."+status.String())
+		label = msg(c, key)
 	}
 	var tone ui.Color
 	var icon *ui.SVG
@@ -71,7 +72,7 @@ func StatusIndicator(c *ui.Context, status Status, opts StatusIndicatorOptions)
 		} else {
 			ui.Icon(c, icon).Size(16, 16).TextColor(tone)
 		}
-		ui.Text(c, label).TextColor(k.Text).FontSize(theme.BodySize).SingleLine()
+		ui.Text(c, label).TextColor(k.Text).FontSize(FontSize(c, theme.BodySize)).SingleLine()
 	})
 	return row
 }
diff --git a/testdata/snapshots/darwin/progress-dark.png b/testdata/snapshots/darwin/progress-dark.png
index 28c32d3..cead596 100644
Binary files a/testdata/snapshots/darwin/progress-dark.png and b/testdata/snapshots/darwin/progress-dark.png differ
diff --git a/testdata/snapshots/darwin/progress-light.png b/testdata/snapshots/darwin/progress-light.png
index ffa4b25..459659c 100644
Binary files a/testdata/snapshots/darwin/progress-light.png and b/testdata/snapshots/darwin/progress-light.png differ
diff --git a/toast.go b/toast.go
index e15a6d4..872997a 100644
--- a/toast.go
+++ b/toast.go
@@ -44,7 +44,10 @@ type toastItem struct {
 }
 
 // toastQueue holds a window's toasts, visible ones first in order shown.
-type toastQueue struct{ items []toastItem }
+type toastQueue struct {
+	items []toastItem
+	wake  time.Time // when Toaster last asked for a frame; zero for none
+}
 
 type toastKey struct{}
 
@@ -64,6 +67,7 @@ func (q *toastQueue) push(m ToastMessage, now time.Time) {
 	if m.Message == "" {
 		panic("mujica: toast needs a Message")
 	}
+	_ = m.Severity.String() // panics on an unknown Severity
 	if m.ID == "" {
 		m.ID = m.Message
 	}
@@ -106,8 +110,8 @@ func (it *toastItem) elapsed(now time.Time) time.Duration {
 	return it.spent + now.Sub(it.runFrom)
 }
 
-// expire drops toasts whose time ran out and returns the wait until the next does.
-func (q *toastQueue) expire(now time.Time) (next time.Duration) {
+// expire drops toasts whose time ran out and shows queued ones.
+func (q *toastQueue) expire(now time.Time) {
 	live := q.items[:0]
 	for _, it := range q.items {
 		if it.visible && it.life > 0 && it.elapsed(now) >= it.life {
@@ -118,6 +122,15 @@ func (q *toastQueue) expire(now time.Time) (next time.Duration) {
 	}
 	q.items = live
 	q.promote(now)
+}
+
+// settle pauses the toasts held, resumes the rest, and returns the wait until one expires.
+func (q *toastQueue) settle(now time.Time, held map[string]bool) (next time.Duration) {
+	for _, it := range q.items {
+		if it.visible {
+			q.pause(it.msg.ID, held[it.msg.ID], now)
+		}
+	}
 	for _, it := range q.items {
 		if it.visible && it.life > 0 && !it.runFrom.IsZero() {
 			left := it.life - it.elapsed(now)
@@ -172,15 +185,12 @@ func DismissToast(c *ui.Context, id string) {
 	c.Invalidate()
 }
 
-// Toaster draws the window's toasts at its bottom right. Call it once per
-// frame, last in the view. Toasts never take the focus; Tab reaches their
-// buttons. Hover or focus inside a toast pauses its time.
+// Toaster draws the window's toasts, never taking the focus; call it last in the view each frame.
 func Toaster(c *ui.Context) ToasterResult {
 	q := toasts(c)
 	now := c.Now()
-	if next := q.expire(now); next > 0 {
-		c.After(next)
-	}
+	q.expire(now)
+	held := map[string]bool{}
 	var res ToasterResult
 	if len(q.items) == 0 {
 		return res
@@ -201,8 +211,8 @@ func Toaster(c *ui.Context) ToasterResult {
 					q.items[i].announced = true
 					c.Announce(it.msg.Message)
 				}
-				action, closed, held := toastCard(c, k, u, min(360, w-u*8), it.msg)
-				q.pause(it.msg.ID, held, now)
+				action, closed, hold := toastCard(c, k, u, min(360, w-u*8), it.msg)
+				held[it.msg.ID] = hold
 				switch {
 				case action:
 					res.Action = it.msg.ID
@@ -220,6 +230,12 @@ func Toaster(c *ui.Context) ToasterResult {
 			c.Invalidate()
 		}
 	}
+	// Scheduled after resuming, so a toast released this frame still expires.
+	q.wake = time.Time{}
+	if next := q.settle(now, held); next > 0 {
+		q.wake = now.Add(next)
+		c.After(next)
+	}
 	return res
 }
 
diff --git a/toast_test.go b/toast_test.go
index d4425ba..c0da1f0 100644
--- a/toast_test.go
+++ b/toast_test.go
@@ -28,7 +28,8 @@ func TestToastQueueLimitsVisible(t *testing.T) {
 		t.Fatalf("visible %v waiting %v", v, w)
 	}
 	// d starts its 5 s only when it shows.
-	if next := q.expire(t0.Add(ToastDuration)); next != ToastDuration {
+	q.expire(t0.Add(ToastDuration))
+	if next := q.settle(t0.Add(ToastDuration), nil); next != ToastDuration {
 		t.Fatalf("next wake %v", next)
 	}
 	if v := toastIDs(&q, true); !slices.Equal(v, []string{"d", "e"}) {
@@ -66,15 +67,16 @@ func TestToastQueueErrorsStayAndPauseHolds(t *testing.T) {
 	t0 := time.Unix(0, 0)
 	q.push(ToastMessage{ID: "e", Severity: SeverityError, Message: "Failed"}, t0)
 	q.push(ToastMessage{ID: "w", Severity: SeverityWarning, Message: "Slow", Action: "Details"}, t0)
-	q.pause("w", true, t0.Add(4*time.Second))
-	if next := q.expire(t0.Add(time.Hour)); next != 0 {
+	q.settle(t0.Add(4*time.Second), map[string]bool{"w": true})
+	q.expire(t0.Add(time.Hour))
+	if next := q.settle(t0.Add(time.Hour), map[string]bool{"w": true}); next != 0 {
 		t.Fatalf("paused toast still counts down: %v", next)
 	}
 	if !slices.Equal(toastIDs(&q, true), []string{"e", "w"}) {
 		t.Fatalf("visible %v", toastIDs(&q, true))
 	}
-	q.pause("w", false, t0.Add(time.Hour))
-	if next := q.expire(t0.Add(time.Hour)); next != time.Second {
+	// Released: the wake-up is computed after resuming, in the same call.
+	if next := q.settle(t0.Add(time.Hour), nil); next != time.Second {
 		t.Fatalf("resumed toast left %v, want 1s", next)
 	}
 	q.expire(t0.Add(time.Hour + time.Second))
@@ -84,7 +86,7 @@ func TestToastQueueErrorsStayAndPauseHolds(t *testing.T) {
 }
 
 func TestToastQueuePanics(t *testing.T) {
-	for _, m := range []ToastMessage{{}, {Message: "x", Duration: -1}} {
+	for _, m := range []ToastMessage{{}, {Message: "x", Duration: -1}, {Message: "x", Severity: 9}} {
 		func() {
 			defer func() {
 				if recover() == nil {
@@ -156,27 +158,41 @@ func TestToastKeepsFocusAndEscapeCloses(t *testing.T) {
 }
 
 func TestToastExpiresAndHoverPauses(t *testing.T) {
-	var res ToasterResult
-	tt := toastTester(ToastMessage{Message: "Copied", Duration: 40 * time.Millisecond}, &res)
+	var q *toastQueue
+	const life = 40 * time.Millisecond
+	tt := ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{})
+		if Button(c, "Notify", ButtonOptions{}).Clicked() {
+			ShowToast(c, ToastMessage{Message: "Copied", Duration: life})
+		}
+		q = toasts(c)
+		Toaster(c)
+	}, 600, 400)
 	_ = tt.Click("Notify")
-	time.Sleep(60 * time.Millisecond)
-	tt.Frame()
-	if tt.HasText("Copied") {
-		t.Fatal("toast outlived its duration")
+	if q.wake.IsZero() {
+		t.Fatal("no wake-up scheduled for a running toast")
 	}
-	_ = tt.Click("Notify")
 	r, _ := tt.Find("Copied")
 	tt.Move(r.X+r.W/2, r.Y+r.H/2)
-	time.Sleep(60 * time.Millisecond)
-	tt.Frame()
+	if !q.wake.IsZero() {
+		t.Fatal("hovered toast still schedules its expiry")
+	}
+	time.Sleep(2 * life)
+	released := time.Now()
+	tt.Move(5, 395)
+	done := time.Now()
+	// The frame that ends the hover must schedule the expiry itself.
+	if q.wake.IsZero() || q.wake.Before(released) || q.wake.After(done.Add(life)) {
+		t.Fatalf("release scheduled wake %v, released %v", q.wake, released)
+	}
 	if !tt.HasText("Copied") {
 		t.Fatal("hovered toast expired")
 	}
-	tt.Move(5, 395)
-	time.Sleep(60 * time.Millisecond)
+	// Stands in for the frame MyGo's timer runs at q.wake.
+	time.Sleep(time.Until(q.wake) + 5*time.Millisecond)
 	tt.Frame()
 	if tt.HasText("Copied") {
-		t.Fatal("toast stayed after the pointer left")
+		t.Fatal("toast stayed after its wake-up")
 	}
 }