diff --git a/autoload/clock.gd b/autoload/clock.gd
new file mode 100644
index 0000000..ddd094a
--- /dev/null
+++ b/autoload/clock.gd
@@ -0,0 +1,138 @@
+extends Node
+## In-game clock: sim-tick → day, hour, minute, darkness factor.
+##
+## Design (docs/architecture.md "Time / tick model"):
+##   - 1 in-game day = TICKS_PER_DAY sim ticks
+##       4800 ticks/day = 240 s real at 1× = 48 s at Fast (5×) = 20 s at Ultra (12×)
+##   - 24 in-game hours per day → TICKS_PER_HOUR = 200
+##   - TICKS_PER_MINUTE = 200 / 60 = 3 (integer floor; ~3.33 ticks per in-game min)
+##
+## Time-of-day phases (docs/design.md "Day/Night cycle"):
+##   Night: 22:00–05:00
+##   Dawn:  05:00–07:00 (2-hour smooth ramp, darkness 1.0 → 0.0)
+##   Day:   07:00–19:00
+##   Dusk:  19:00–22:00 (3-hour smooth ramp, darkness 0.0 → 1.0)
+##
+## darkness_factor() returns 0.0 (full daylight) to 1.0 (deepest night).
+##
+## Game starts at Day 1, 06:00 (mid-dawn — atmospheric, not full dark).
+##
+## Save seam: save_dict() / apply_dict() persist _start_offset_ticks so
+## the time-of-day survives a session reload.
+
+const TICKS_PER_DAY: int  = 4800
+const TICKS_PER_HOUR: int = 200
+## Integer floor of 200/60 ≈ 3.33. Minute display rounds down — fine for a clock.
+const TICKS_PER_MINUTE: int = TICKS_PER_HOUR / 60
+
+const START_HOUR: int    = 6
+const HOURS_PER_DAY: int = 24
+
+# Phase boundaries (in-game hours, inclusive lower bound).
+const DAWN_START_HOUR: int = 5
+const DAWN_END_HOUR: int   = 7
+const DUSK_START_HOUR: int = 19
+const DUSK_END_HOUR: int   = 22
+
+## Internal: added to Sim.tick so we begin at START_HOUR rather than midnight.
+var _start_offset_ticks: int = START_HOUR * TICKS_PER_HOUR
+
+## Fired when the time-phase transitions (Night → Dawn, Dawn → Day, etc.).
+signal phase_changed(phase: StringName)
+
+const PHASE_NIGHT: StringName = &"night"
+const PHASE_DAWN:  StringName = &"dawn"
+const PHASE_DAY:   StringName = &"day"
+const PHASE_DUSK:  StringName = &"dusk"
+
+var _last_emitted_phase: StringName = &""
+
+
+func _ready() -> void:
+	EventBus.sim_tick.connect(_on_sim_tick)
+
+
+# ── public API ───────────────────────────────────────────────────────────────
+
+## Current in-game day (1-indexed). Day 1 starts at boot.
+func current_day() -> int:
+	return 1 + (_offset_ticks() / TICKS_PER_DAY)
+
+
+## Current hour 0..23.
+func current_hour() -> int:
+	return (_offset_ticks() / TICKS_PER_HOUR) % HOURS_PER_DAY
+
+
+## Current minute 0..59.
+func current_minute() -> int:
+	var ticks_into_hour: int = _offset_ticks() % TICKS_PER_HOUR
+	return (ticks_into_hour * 60) / TICKS_PER_HOUR
+
+
+## Time of day as a 0..1 fraction (0.0 = midnight, 0.5 = noon).
+func time_of_day_fraction() -> float:
+	return float(_offset_ticks() % TICKS_PER_DAY) / float(TICKS_PER_DAY)
+
+
+## Returns 0.0 (full daylight) to 1.0 (deepest night).
+##
+## Ramp shapes:
+##   Day   [07:00–19:00] → 0.0 flat
+##   Night [22:00–05:00] → 1.0 flat
+##   Dawn  [05:00–07:00] → 1.0 ramps down to 0.0 linearly over 2 hours
+##   Dusk  [19:00–22:00] → 0.0 ramps up to 1.0 linearly over 3 hours
+func darkness_factor() -> float:
+	var h: float = float(current_hour()) + float(current_minute()) / 60.0
+	# Full daylight band.
+	if h >= DAWN_END_HOUR and h < DUSK_START_HOUR:
+		return 0.0
+	# Full night band — handles the wrap (h >= 22 OR h < 5).
+	if h >= DUSK_END_HOUR or h < DAWN_START_HOUR:
+		return 1.0
+	# Dawn ramp: 1.0 at 05:00 → 0.0 at 07:00
+	if h < DAWN_END_HOUR:
+		return 1.0 - (h - DAWN_START_HOUR) / float(DAWN_END_HOUR - DAWN_START_HOUR)
+	# Dusk ramp: 0.0 at 19:00 → 1.0 at 22:00
+	return (h - DUSK_START_HOUR) / float(DUSK_END_HOUR - DUSK_START_HOUR)
+
+
+## Current phase as a StringName constant. Phase transitions emit phase_changed.
+func current_phase() -> StringName:
+	var h: int = current_hour()
+	if h < DAWN_START_HOUR or h >= DUSK_END_HOUR:
+		return PHASE_NIGHT
+	if h < DAWN_END_HOUR:
+		return PHASE_DAWN
+	if h < DUSK_START_HOUR:
+		return PHASE_DAY
+	return PHASE_DUSK
+
+
+## "HH:MM" formatted 24-hour time string.
+func time_string() -> String:
+	return "%02d:%02d" % [current_hour(), current_minute()]
+
+
+# ── internal ─────────────────────────────────────────────────────────────────
+
+func _offset_ticks() -> int:
+	return _start_offset_ticks + Sim.tick
+
+
+func _on_sim_tick(_n: int) -> void:
+	var phase: StringName = current_phase()
+	if phase != _last_emitted_phase:
+		_last_emitted_phase = phase
+		emit_signal("phase_changed", phase)
+		Audit.log("clock", "phase → %s (day %d, %s)" % [phase, current_day(), time_string()])
+
+
+# ── save / load ──────────────────────────────────────────────────────────────
+
+func save_dict() -> Dictionary:
+	return {"start_offset_ticks": _start_offset_ticks}
+
+
+func apply_dict(d: Dictionary) -> void:
+	_start_offset_ticks = int(d.get("start_offset_ticks", START_HOUR * TICKS_PER_HOUR))
diff --git a/autoload/clock.gd.uid b/autoload/clock.gd.uid
new file mode 100644
index 0000000..cd85a24
--- /dev/null
+++ b/autoload/clock.gd.uid
@@ -0,0 +1 @@
+uid://b0rnjjv1rag7d
diff --git a/autoload/strings.gd b/autoload/strings.gd
index 6c7024e..467a262 100644
--- a/autoload/strings.gd
+++ b/autoload/strings.gd
@@ -19,6 +19,8 @@ const TABLE: Dictionary = {
 	&"speed.ultra": "12×",
 	# HUD
 	&"hud.tick": "Tick: {n}",
+	# Phase 11 — in-game clock display ("{d}" = day, "{t}" = "HH:MM")
+	&"clock.format": "Day {d}, {t}",
 	# Pawn state labels
 	&"pawn.state.idle": "idle",
 	&"pawn.state.walking": "walking",
@@ -41,6 +43,8 @@ const TABLE: Dictionary = {
 	# Phase 7 — pawn hunger states
 	&"pawn.state.eating":   "eating",
 	&"pawn.state.hungry":   "hungry",
+	# Phase 11 — mood thoughts (player-visible in pawn-detail, Phase 17)
+	&"thought.in_darkness": "In darkness",
 	# Phase 6 — quality tier labels
 	&"quality.shoddy":     "Shoddy",
 	&"quality.normal":     "Normal",
diff --git a/autoload/world.gd b/autoload/world.gd
index 01aa8b8..8450948 100644
--- a/autoload/world.gd
+++ b/autoload/world.gd
@@ -54,6 +54,13 @@ var crops: Array = []
 # Storyteller also reads beds.size() for the "First Beds" state predicate.
 var beds: Array = []
 
+# Phase 11 — light-source entities (Torch + Hearth workbench). Entities call
+# register_light_source() in _ready and unregister_light_source() in _exit_tree.
+# is_tile_lit() is queried by the "in darkness" thought and any future
+# darkness-rendering shader bridge. All entries expose the duck-type interface:
+#   is_on() → bool | get_light_tile() → Vector2i | get_light_radius() → int
+var light_sources: Array = []
+
 # Phase 4 — hauling dirty set. Keys are Items, value is unused (we just use .keys()).
 # An Item is added when it spawns (Tree.fell, Rock.mined, workbench drop, ...)
 # and removed when it lands at its highest-priority valid destination.
@@ -193,6 +200,33 @@ func unregister_bed(b) -> void:
 	beds.erase(b)
 
 
+# ── Phase 11: light-source registry ────────────────────────────────────────
+
+func register_light_source(ls) -> void:
+	if not light_sources.has(ls):
+		light_sources.append(ls)
+
+
+func unregister_light_source(ls) -> void:
+	light_sources.erase(ls)
+
+
+## Returns true if `tile` is within get_light_radius() of any is_on() light
+## source. Uses Manhattan distance (no wall-occlusion in Phase 11; Phase 13
+## may add BFS-based occlusion through the room/roof system).
+##
+## Called by the "in darkness" Thought trigger on each pawn sim tick.
+## O(light_sources) per call; trivial at our scale (< 50 sources in MVP).
+func is_tile_lit(p_tile: Vector2i) -> bool:
+	for ls in light_sources:
+		if not ls.is_on():
+			continue
+		var d: int = abs(ls.get_light_tile().x - p_tile.x) + abs(ls.get_light_tile().y - p_tile.y)
+		if d <= ls.get_light_radius():
+			return true
+	return false
+
+
 # Called by Wall.on_build_tick() when construction completes.
 # Stamps the data-only Wall TileMap layer so room/roof/save logic sees the
 # wall. World scene exposes wall_layer via a getter set during _ready.
diff --git a/docs/implementation.md b/docs/implementation.md
index d4c11ad..37a1c7e 100644
--- a/docs/implementation.md
+++ b/docs/implementation.md
@@ -15,6 +15,7 @@ Effort estimates are wall-time at **focused solo pace**. Scale up generously for
 | ✅ done — Recipe + Bill data, Workbench entity (Carpenter / Smelter via label_text), CraftingProvider, KIND_CRAFT toil, 5-tier Quality system, Pawn skills, wall-trap fix | **Phase 6 — Production: workbenches, recipes, bills, quality** |
 | ✅ done — Crop entity (6-stage state machine), PlantProvider (harvest), Hunger need + EatProvider w/ food-priority ladder, Hearth/Millstone via label_text, grain/flour/bread/meal types | **Phase 7 — Plants, cooking, hunger** |
 | ✅ done — Bed entity (quality-tinted, claim/release), Sleep need + SleepProvider + KIND_SLEEP toil, Thought registry + mood compute + Sulking soft-break, Decision Layer-1 interrupt | **Phase 8 — Sleep, mood, thoughts** |
+| ✅ done (out of order — taken before Phase 9 for the atmospheric win) — Clock autoload + dawn/day/dusk/night phases + darkness_factor ramp, CanvasModulate global tint, Torch entity + PointLight2D + procedural radial gradient, Hearth opts-in as light source, in_darkness thought | **Phase 11 — Day/night + Lighting** |
 | ⏳ next | **Phase 9 — Status effects + Medicine** |
 
 Use this doc as a checklist: tick boxes as items complete, and update the **Status** row above whenever a phase rolls over. The last bullet of each phase is the *acceptance demo* — the phase is "done" when you can perform it.
diff --git a/project.godot b/project.godot
index c12bdab..72ed2ba 100644
--- a/project.godot
+++ b/project.godot
@@ -24,6 +24,7 @@ Audit="*res://autoload/audit.gd"
 GameState="*res://autoload/game_state.gd"
 World="*res://autoload/world.gd"
 Sim="*res://autoload/sim.gd"
+Clock="*res://autoload/clock.gd"
 SaveSystem="*res://autoload/save_system.gd"
 MCPScreenshot="*res://addons/godot_mcp/mcp_screenshot_service.gd"
 MCPInputService="*res://addons/godot_mcp/mcp_input_service.gd"
diff --git a/scenes/ai/thought_catalog.gd b/scenes/ai/thought_catalog.gd
index 0da496e..d6b6f41 100644
--- a/scenes/ai/thought_catalog.gd
+++ b/scenes/ai/thought_catalog.gd
@@ -77,6 +77,19 @@ static func slept_on_floor() -> Thought:
 	return t
 
 
+## Mood penalty while a pawn is in an unlit tile at night.
+## modifier=-3, max_stacks=1, PERSISTENT.
+## Phase 17 polish may split into "outdoor dark" / "cave dark" tiers.
+static func in_darkness() -> Thought:
+	var t := Thought.new()
+	t.id = &"in_darkness"
+	t.label = "In darkness"
+	t.modifier = -3
+	t.lifetime = Thought.Lifetime.PERSISTENT
+	t.max_stacks = 1
+	return t
+
+
 ## Small mood boost after eating a cooked meal or bread.
 ## Fires in _tick_eat when item_type is TYPE_MEAL or TYPE_BREAD.
 ## Stacks up to 3 (multiple good meals compound, but cap at 3).
diff --git a/scenes/entities/torch.gd b/scenes/entities/torch.gd
new file mode 100644
index 0000000..bf17604
--- /dev/null
+++ b/scenes/entities/torch.gd
@@ -0,0 +1,245 @@
+class_name Torch extends Node2D
+## Torch furniture entity — buildable wall-hung or floor-standing light source.
+##
+## Rendered as a small stick + wrapped head + flame using _draw() in the same
+## 3/4-perspective convention as Wall / Bed / Workbench. Ghost state (40% alpha)
+## while construction is in progress; solid + lit once _completed.
+##
+## Light model (docs/architecture.md "LightingSystem"):
+##   Emits a PointLight2D with a procedural radial-gradient texture (soft
+##   falloff). The Godot visual light is additive with CanvasModulate for
+##   night-time darkness. The sim-side light radius (LIGHT_RADIUS tiles,
+##   Manhattan distance) is registered with World.light_sources so that
+##   is_tile_lit() can answer "in darkness" thought queries cheaply.
+##
+## Light-source duck-type interface (shared with Hearth / Workbench):
+##   is_on()           → bool
+##   get_light_tile()  → Vector2i
+##   get_light_radius() → int
+##
+## Build model (same BuildJob interface as Wall / Bed / Workbench):
+##   BUILD_TICKS ticks via the standard BuildJob toil; PointLight2D enabled
+##   only after _complete().
+##
+## Save/load: to_dict / from_dict capture tile, label_text, build_progress,
+## _completed, _is_on. Phase 16 wires these into the full save layer.
+##
+## World registration: World.register_light_source / World.unregister_light_source
+## called from _ready / _exit_tree.
+
+const TILE_SIZE_PX: int = 16
+
+## Sim ticks to build a torch (30 ticks ≈ 1.5 sim seconds at 1×).
+const BUILD_TICKS: int = 30
+
+## Sim-side light radius in tiles (Manhattan). Max 8 per architecture.md.
+const LIGHT_RADIUS: int = 6
+
+## Pixel size of the procedural radial gradient used for the PointLight2D.
+## Larger values give a smoother falloff; 64 is sufficient for a 6-tile radius.
+const LIGHT_TEXTURE_SIZE: int = 64
+
+# ── exports ───────────────────────────────────────────────────────────────────
+
+## Tile position of this torch in world-tile coordinates.
+@export var tile: Vector2i = Vector2i.ZERO
+
+## Player-visible label. Drives Audit logs and job descriptions.
+@export var label_text: String = "Torch"
+
+# ── state ─────────────────────────────────────────────────────────────────────
+
+## Ticks of construction work applied so far. 0..BUILD_TICKS.
+var build_progress: int = 0
+
+## True once build_progress >= BUILD_TICKS.
+var _completed: bool = false
+
+## Whether the torch is emitting light. Always true for Phase 11;
+## Phase 17 may add fuel consumption or a player on/off toggle.
+var _is_on: bool = true
+
+## PointLight2D child node for Godot's visual lighting pipeline.
+## Built in _ready(); enabled only once _complete() fires.
+var _light: PointLight2D = null
+
+
+# ── lifecycle ─────────────────────────────────────────────────────────────────
+
+func _ready() -> void:
+	# Bottom-anchor so Y-sort occludes pawns correctly (same pivot as Wall/Bed).
+	position = Vector2(
+		tile.x * TILE_SIZE_PX + TILE_SIZE_PX / 2.0,
+		tile.y * TILE_SIZE_PX + TILE_SIZE_PX
+	)
+	World.register_light_source(self)
+	_light = _build_point_light_2d()
+	add_child(_light)
+	_light.enabled = false   # dark until built
+	queue_redraw()
+
+
+func _exit_tree() -> void:
+	World.unregister_light_source(self)
+
+
+## One-shot initialiser. Call after add_child() so _ready() has already fired.
+func setup(p_tile: Vector2i) -> void:
+	tile = p_tile
+	position = Vector2(
+		tile.x * TILE_SIZE_PX + TILE_SIZE_PX / 2.0,
+		tile.y * TILE_SIZE_PX + TILE_SIZE_PX
+	)
+	queue_redraw()
+
+
+# ── BuildJob interface (matches Wall / Bed / Workbench shape) ─────────────────
+
+## True while the torch still needs construction work.
+func is_buildable() -> bool:
+	return not _completed
+
+
+## Human-readable label for job descriptions and Audit logs.
+func label() -> String:
+	return label_text
+
+
+## Called by the BUILD toil in JobRunner once per sim tick while the pawn works.
+## Advances build_progress and completes the torch at BUILD_TICKS.
+func on_build_tick() -> void:
+	if _completed:
+		return
+	build_progress += 1
+	queue_redraw()
+	if build_progress >= BUILD_TICKS:
+		_complete()
+
+
+## True once the torch has been fully built.
+func is_completed() -> bool:
+	return _completed
+
+
+## Torches are walkable — pawns step around them visually but the tile remains
+## passable for pathfinding purposes.
+func blocks_pathing_when_complete() -> bool:
+	return false
+
+
+# ── light-source duck-type interface ──────────────────────────────────────────
+## Used by World.is_tile_lit() and the "in darkness" thought.
+## Hearth / Workbench exposes the same three functions.
+
+## True when the torch is built and switched on.
+func is_on() -> bool:
+	return _completed and _is_on
+
+
+## The tile this light source occupies (for distance calculations).
+func get_light_tile() -> Vector2i:
+	return tile
+
+
+## The sim-side Manhattan-distance radius of this light source.
+func get_light_radius() -> int:
+	return LIGHT_RADIUS
+
+
+## Toggle the torch on/off. Phase 17 may call this from a fuel-depletion system
+## or player action; safe to call any time including before _complete().
+func set_on(value: bool) -> void:
+	_is_on = value
+	if _light != null:
+		_light.enabled = _completed and _is_on
+	Audit.log("light", "torch at %s set_on → %s" % [tile, value])
+
+
+# ── save / load ───────────────────────────────────────────────────────────────
+
+## Serialise all persistent state for World save (wired in Phase 16).
+func to_dict() -> Dictionary:
+	return {
+		"tile_x": tile.x,
+		"tile_y": tile.y,
+		"label_text": label_text,
+		"build_progress": build_progress,
+		"completed": _completed,
+		"is_on": _is_on,
+	}
+
+
+## Restore from a dict produced by to_dict().
+func from_dict(d: Dictionary) -> void:
+	tile = Vector2i(int(d.get("tile_x", 0)), int(d.get("tile_y", 0)))
+	label_text = str(d.get("label_text", "Torch"))
+	build_progress = int(d.get("build_progress", 0))
+	_completed = bool(d.get("completed", false))
+	_is_on = bool(d.get("is_on", true))
+	# _light is rebuilt in _ready() — no need to restore the node.
+	setup(tile)
+
+
+# ── render ─────────────────────────────────────────────────────────────────────
+
+func _draw() -> void:
+	# 3/4-perspective torch — fits within the tile (16×16 local box).
+	# Origin (0,0) = tile bottom-centre. Tile spans local Y: -16 to 0.
+	# Ghost (not yet built) draws at 0.4 alpha.
+	var alpha: float = 1.0 if _completed else 0.4
+
+	# Stick — narrow vertical brown rect, centred horizontally.
+	draw_rect(Rect2(Vector2(-1.0, -9.0), Vector2(2.0, 9.0)), Color(0.35, 0.22, 0.10, alpha))
+
+	# Wrapped head — slightly wider, darker, at the top of the stick.
+	draw_rect(Rect2(Vector2(-2.0, -13.0), Vector2(4.0, 4.0)), Color(0.20, 0.14, 0.06, alpha))
+
+	# Flame — only when built and on; two overlapping circles for depth.
+	if _completed and _is_on:
+		draw_circle(Vector2(0.0, -15.0), 2.5, Color(1.0, 0.65, 0.10, alpha))
+		draw_circle(Vector2(0.0, -16.0), 1.5, Color(1.0, 0.90, 0.40, alpha))
+
+
+# ── internal helpers ──────────────────────────────────────────────────────────
+
+## Construct and return the PointLight2D that provides Godot-side visual
+## lighting. The light is positioned at the flame, not the tile base.
+func _build_point_light_2d() -> PointLight2D:
+	var p := PointLight2D.new()
+	p.texture = _build_radial_light_texture(LIGHT_TEXTURE_SIZE)
+	# Scale the texture so its radius in world-pixels matches LIGHT_RADIUS tiles.
+	p.texture_scale = float(LIGHT_RADIUS) * float(TILE_SIZE_PX) / float(LIGHT_TEXTURE_SIZE) * 2.0
+	p.color = Color(1.0, 0.85, 0.55, 1.0)   # warm fire tint
+	p.energy = 1.2
+	# Offset upward so the light originates from the flame position.
+	p.position = Vector2(0.0, -15.0)
+	return p
+
+
+## Build a soft radial gradient Image and return it as an ImageTexture.
+## White centre, fades to transparent at the edge via smoothstep falloff.
+## Called once per torch in _ready(); result is ~4 KB of VRAM at 64×64 RGBA8.
+static func _build_radial_light_texture(size: int) -> Texture2D:
+	var img := Image.create(size, size, false, Image.FORMAT_RGBA8)
+	var cx: float = float(size) / 2.0
+	var cy: float = float(size) / 2.0
+	var max_r: float = float(size) / 2.0
+	for x in size:
+		for y in size:
+			var dx: float = float(x) - cx
+			var dy: float = float(y) - cy
+			var d: float = sqrt(dx * dx + dy * dy)
+			var t: float = clampf(1.0 - d / max_r, 0.0, 1.0)
+			# Smoothstep so the edge is soft rather than a hard circle cutoff.
+			var a: float = t * t * (3.0 - 2.0 * t)
+			img.set_pixel(x, y, Color(1.0, 1.0, 1.0, a))
+	return ImageTexture.create_from_image(img)
+
+
+## Called when build_progress reaches BUILD_TICKS.
+func _complete() -> void:
+	_completed = true
+	if _light != null:
+		_light.enabled = _is_on
+	queue_redraw()
+	Audit.log("torch", "built at %s" % tile)
diff --git a/scenes/entities/torch.gd.uid b/scenes/entities/torch.gd.uid
new file mode 100644
index 0000000..c40ffcd
--- /dev/null
+++ b/scenes/entities/torch.gd.uid
@@ -0,0 +1 @@
+uid://d0yg2xw7btr1a
diff --git a/scenes/entities/torch.tscn b/scenes/entities/torch.tscn
new file mode 100644
index 0000000..2ad3442
--- /dev/null
+++ b/scenes/entities/torch.tscn
@@ -0,0 +1,8 @@
+[gd_scene load_steps=2 format=3 uid="uid://torch_entity"]
+
+[ext_resource type="Script" path="res://scenes/entities/torch.gd" id="1_torch"]
+
+[node name="Torch" type="Node2D"]
+y_sort_enabled = true
+z_index = 0
+script = ExtResource("1_torch")
diff --git a/scenes/entities/workbench.gd b/scenes/entities/workbench.gd
index f05cb45..9a7c2c6 100644
--- a/scenes/entities/workbench.gd
+++ b/scenes/entities/workbench.gd
@@ -31,6 +31,17 @@ const TILE_SIZE_PX: int = 16
 ## Sim ticks to build a workbench (90 ticks ≈ 4.5 sim seconds at 1×).
 const BUILD_TICKS: int = 90
 
+# ── Phase 11: light-source support ───────────────────────────────────────────
+## Workbenches whose label_text is in this list emit light when completed.
+## Currently only the Hearth (open-fire cooking) qualifies.
+const LIGHT_EMITTING_LABELS: Array[String] = ["Hearth"]
+
+## Sim-side Manhattan-distance light radius for the Hearth (tiles). Max 8.
+const HEARTH_LIGHT_RADIUS: int = 5
+
+## Pixel size of the procedural radial gradient used for PointLight2D.
+const LIGHT_TEXTURE_SIZE: int = 64
+
 # ── exports ───────────────────────────────────────────────────────────────────
 
 ## Tile position of this workbench in world-tile coordinates.
@@ -68,6 +79,11 @@ var current_bill = null
 ## JobRunner reads this to decide whether the recipe's work_ticks are done.
 var current_work_progress: int = 0
 
+## PointLight2D child for workbenches that emit light (Hearth). null for all
+## others. Built in _ready() when label_text is in LIGHT_EMITTING_LABELS;
+## enabled only after _complete() fires.
+var _light: PointLight2D = null
+
 
 # ── lifecycle ─────────────────────────────────────────────────────────────────
 
@@ -78,11 +94,20 @@ func _ready() -> void:
 		tile.y * TILE_SIZE_PX + TILE_SIZE_PX
 	)
 	World.register_workbench(self)
+	# Phase 11: light-emitting workbenches register with the light-source registry.
+	# All workbenches register; non-emitters return false from is_on() so
+	# World.is_tile_lit() skips them at zero cost.
+	World.register_light_source(self)
+	if label_text in LIGHT_EMITTING_LABELS:
+		_light = _build_point_light_2d()
+		add_child(_light)
+		_light.enabled = false   # dark until built
 	queue_redraw()
 
 
 func _exit_tree() -> void:
 	World.unregister_workbench(self)
+	World.unregister_light_source(self)
 
 
 ## One-shot initialiser. Call after add_child() so _ready() has fired.
@@ -180,6 +205,29 @@ func on_craft_interrupted() -> void:
 	current_work_progress = 0
 
 
+# ── Phase 11: light-source duck-type interface ────────────────────────────────
+## Shared by Torch. World.is_tile_lit() and the "in darkness" thought call these.
+
+## True when this workbench emits light and has finished construction.
+## Non-emitting workbenches (Carpenter, Smelter, Millstone) always return false.
+func is_on() -> bool:
+	return _completed and label_text in LIGHT_EMITTING_LABELS
+
+
+## The tile this light source occupies (for Manhattan-distance calculation).
+func get_light_tile() -> Vector2i:
+	return tile
+
+
+## The sim-side Manhattan-distance radius of this light source.
+## Returns 0 for non-emitting workbenches; World.is_tile_lit() still calls this
+## but d <= 0 is never true for a non-adjacent tile so it's a no-op in practice.
+func get_light_radius() -> int:
+	if label_text in LIGHT_EMITTING_LABELS:
+		return HEARTH_LIGHT_RADIUS
+	return 0
+
+
 # ── save / load ───────────────────────────────────────────────────────────────
 
 ## Serialise workbench state for World save (wired in Phase 16).
@@ -352,5 +400,43 @@ func _draw_generic(alpha: float) -> void:
 
 func _complete() -> void:
 	_completed = true
+	# Phase 11: enable PointLight2D for light-emitting workbenches on completion.
+	if _light != null:
+		_light.enabled = is_on()
 	queue_redraw()
 	Audit.log("workbench", "%s built at %s" % [label_text, tile])
+
+
+# ── Phase 11: internal light helpers ─────────────────────────────────────────
+
+## Construct and return the PointLight2D that provides Godot-side visual lighting.
+## Mirrors Torch._build_point_light_2d(). Duplicated here to avoid a cross-file
+## dependency; the ~20 lines of duplication is the lesser cost.
+func _build_point_light_2d() -> PointLight2D:
+	var p := PointLight2D.new()
+	p.texture = _build_radial_light_texture(LIGHT_TEXTURE_SIZE)
+	# Scale so the texture radius covers HEARTH_LIGHT_RADIUS tiles in world-pixels.
+	p.texture_scale = float(HEARTH_LIGHT_RADIUS) * float(TILE_SIZE_PX) / float(LIGHT_TEXTURE_SIZE) * 2.0
+	p.color = Color(1.0, 0.80, 0.50, 1.0)   # warm hearthfire tint, slightly redder than torch
+	p.energy = 1.0
+	# Offset upward so the light originates from the flame area, not the tile base.
+	p.position = Vector2(0.0, -10.0)
+	return p
+
+
+## Build a soft radial gradient Image and return it as an ImageTexture.
+## White centre fades to transparent at the edge via smoothstep falloff.
+static func _build_radial_light_texture(size: int) -> Texture2D:
+	var img := Image.create(size, size, false, Image.FORMAT_RGBA8)
+	var cx: float = float(size) / 2.0
+	var cy: float = float(size) / 2.0
+	var max_r: float = float(size) / 2.0
+	for x in size:
+		for y in size:
+			var dx: float = float(x) - cx
+			var dy: float = float(y) - cy
+			var d: float = sqrt(dx * dx + dy * dy)
+			var t: float = clampf(1.0 - d / max_r, 0.0, 1.0)
+			var a: float = t * t * (3.0 - 2.0 * t)
+			img.set_pixel(x, y, Color(1.0, 1.0, 1.0, a))
+	return ImageTexture.create_from_image(img)
diff --git a/scenes/pawn/pawn.gd b/scenes/pawn/pawn.gd
index 9e0ef28..3ce7e64 100644
--- a/scenes/pawn/pawn.gd
+++ b/scenes/pawn/pawn.gd
@@ -286,6 +286,13 @@ func _process_thoughts() -> void:
 	# 2. Sync PERSISTENT thoughts.
 	_sync_persistent_thought(&"hungry", is_hungry(), ThoughtCatalog.hungry())
 	_sync_persistent_thought(&"tired", is_tired(), ThoughtCatalog.tired())
+	# Phase 11 — in_darkness fires when past dusk/before dawn AND the pawn's
+	# tile is unlit.  architecture.md "LightingSystem": is_lit = light_map > 0.2;
+	# darkness_factor > 0.3 spans dusk-mid through dawn-mid.
+	# Phase 13 may add wall-occlusion via room BFS; for now radius-8 falloff only.
+	var _dark_time := Clock.darkness_factor() > 0.3
+	var _lit := World.is_tile_lit(tile)
+	_sync_persistent_thought(&"in_darkness", _dark_time and not _lit, ThoughtCatalog.in_darkness())
 	# 3. Recompute if EVENT thoughts expired (persistent syncs call _recompute_mood internally).
 	if dirty:
 		_recompute_mood()
diff --git a/scenes/ui/top_bar.gd b/scenes/ui/top_bar.gd
index 478f97a..7ed3efb 100644
--- a/scenes/ui/top_bar.gd
+++ b/scenes/ui/top_bar.gd
@@ -9,22 +9,27 @@ extends CanvasLayer
 const ACTIVE_MODULATE := Color(1.2, 1.2, 0.8)
 const IDLE_MODULATE   := Color.WHITE
 
-@onready var pause_btn  : Button = $Anchor/ButtonRow/PauseBtn
-@onready var normal_btn : Button = $Anchor/ButtonRow/NormalBtn
-@onready var fast_btn   : Button = $Anchor/ButtonRow/FastBtn
-@onready var ultra_btn  : Button = $Anchor/ButtonRow/UltraBtn
-@onready var tick_label : Label  = $Anchor/TickLabel
+@onready var pause_btn   : Button = $Anchor/ButtonRow/PauseBtn
+@onready var normal_btn  : Button = $Anchor/ButtonRow/NormalBtn
+@onready var fast_btn    : Button = $Anchor/ButtonRow/FastBtn
+@onready var ultra_btn   : Button = $Anchor/ButtonRow/UltraBtn
+@onready var tick_label  : Label  = $Anchor/TickLabel
+@onready var clock_label : Label  = $Anchor/ClockLabel
 
 # Maps Speed enum value → the corresponding Button node.
 var _speed_buttons: Dictionary = {}
 
+# Early-out cache: only set clock_label.text when the string changes.
+var _last_clock_text: String = ""
+
 
 func _ready() -> void:
-	pause_btn.text  = Strings.t(&"speed.pause")
-	normal_btn.text = Strings.t(&"speed.normal")
-	fast_btn.text   = Strings.t(&"speed.fast")
-	ultra_btn.text  = Strings.t(&"speed.ultra")
-	tick_label.text = "(boot)"
+	pause_btn.text   = Strings.t(&"speed.pause")
+	normal_btn.text  = Strings.t(&"speed.normal")
+	fast_btn.text    = Strings.t(&"speed.fast")
+	ultra_btn.text   = Strings.t(&"speed.ultra")
+	tick_label.text  = "(boot)"
+	clock_label.text = Strings.t(&"clock.format").format({"d": 1, "t": "06:00"})
 
 	_speed_buttons = {
 		Sim.Speed.PAUSE:  pause_btn,
@@ -40,6 +45,7 @@ func _ready() -> void:
 
 	EventBus.speed_changed.connect(_on_speed_changed)
 	EventBus.sim_tick.connect(_on_sim_tick)
+	EventBus.sim_tick.connect(_on_clock_refresh)
 
 	# Reflect the initial speed state without emitting a signal.
 	_apply_highlight(Sim.current_speed)
@@ -64,6 +70,13 @@ func _on_sim_tick(tick_number: int) -> void:
 	tick_label.text = Strings.t(&"hud.tick").format({"n": tick_number})
 
 
+func _on_clock_refresh(_n: int) -> void:
+	var t: String = Strings.t(&"clock.format").format({"d": Clock.current_day(), "t": Clock.time_string()})
+	if t != _last_clock_text:
+		_last_clock_text = t
+		clock_label.text = t
+
+
 func _apply_highlight(speed: Sim.Speed) -> void:
 	for s: int in _speed_buttons:
 		_speed_buttons[s].modulate = ACTIVE_MODULATE if s == speed else IDLE_MODULATE
diff --git a/scenes/ui/top_bar.tscn b/scenes/ui/top_bar.tscn
index 115a184..eccdebe 100644
--- a/scenes/ui/top_bar.tscn
+++ b/scenes/ui/top_bar.tscn
@@ -34,6 +34,18 @@ text = "5×"
 focus_mode = 0
 text = "12×"
 
+[node name="ClockLabel" type="Label" parent="Anchor"]
+anchor_left = 0.5
+anchor_right = 0.5
+anchor_bottom = 0.0
+offset_left = -80.0
+offset_top = 8.0
+offset_right = 80.0
+offset_bottom = 40.0
+grow_horizontal = 2
+text = "Day 1, 06:00"
+horizontal_alignment = 1
+
 [node name="TickLabel" type="Label" parent="Anchor"]
 anchor_left = 1.0
 anchor_right = 1.0
diff --git a/scenes/world/world.gd b/scenes/world/world.gd
index 8e6d752..7aa4d76 100644
--- a/scenes/world/world.gd
+++ b/scenes/world/world.gd
@@ -29,6 +29,7 @@ const WORKBENCH_SCENE: PackedScene = preload("res://scenes/entities/workbench.ts
 const CROP_SCENE: PackedScene = preload("res://scenes/entities/crop.tscn")
 const ITEM_SCENE: PackedScene = preload("res://scenes/entities/item.tscn")
 const BED_SCENE: PackedScene = preload("res://scenes/entities/bed.tscn")
+const TORCH_SCENE: PackedScene = preload("res://scenes/entities/torch.tscn")
 
 # 3 starting pawns — Phase 2 demo. Phase 7+ replaces this with map-gen + name table.
 const SAMPLE_PAWNS: Array[Dictionary] = [
@@ -51,6 +52,12 @@ const SAMPLE_ROCKS: Array[Vector2i] = [
 # HaulingProvider re-flow cadence — every 5 sim seconds at 1× (100 ticks).
 const HAUL_SWEEP_INTERVAL_TICKS: int = 100
 
+# Phase 11 — global darkness tint. Day = white, night = deep cool blue.
+# Driven by Clock.darkness_factor() (0..1) each sim tick.
+const NIGHT_TINT: Color = Color(0.20, 0.22, 0.40, 1.0)
+const DAY_TINT: Color = Color(1.0, 1.0, 1.0, 1.0)
+
+@onready var dark_overlay: CanvasModulate = $DarkOverlay
 @onready var terrain_layer: TileMapLayer = $Terrain
 @onready var floor_layer: TileMapLayer = $Floor
 @onready var wall_layer: TileMapLayer = $Wall
@@ -395,6 +402,19 @@ func _seed_phase5_demo_buildings() -> void:
 			bed.on_build_tick()
 	Audit.log("world", "phase 8 demo: %d beds pre-built inside cabin" % bed_tiles.size())
 
+	# Phase 11 demo — 2 torches inside cabin (north-east + south-west corners
+	# of interior) so the indoor area stays lit at night. Combined with the
+	# Hearth's light radius=5, the cabin interior should be mostly bright
+	# while the outdoors goes deep-blue tinted.
+	var torch_tiles: Array[Vector2i] = [Vector2i(46, 26), Vector2i(49, 26)]
+	for tt in torch_tiles:
+		var torch: Torch = TORCH_SCENE.instantiate()
+		add_child(torch)
+		torch.setup(tt)
+		while torch.is_buildable():
+			torch.on_build_tick()
+	Audit.log("world", "phase 11 demo: %d torches pre-built inside cabin" % torch_tiles.size())
+
 
 func _spawn_sample_stockpiles() -> void:
 	# Two zones for the Phase 4 acceptance demo:
@@ -463,11 +483,20 @@ func _on_designation_cleared(cell: Vector2i) -> void:
 # ── periodic re-flow (the "wood floats up" cascade) ─────────────────────────
 
 func _on_sim_tick_world_sweep(tick_n: int) -> void:
+	_update_dark_overlay()
 	if tick_n % HAUL_SWEEP_INTERVAL_TICKS != 0:
 		return
 	hauling_provider.sweep_for_better_destinations()
 
 
+# Phase 11 — interpolate CanvasModulate between DAY_TINT and NIGHT_TINT based
+# on Clock.darkness_factor() (0 = full day, 1 = full night).
+# Called every sim tick; Color.lerp is a handful of float ops — negligible cost.
+func _update_dark_overlay() -> void:
+	var f := Clock.darkness_factor()
+	dark_overlay.color = DAY_TINT.lerp(NIGHT_TINT, f)
+
+
 # ── spike: AStarGrid2D query timing at 80² ──────────────────────────────────
 
 func _run_pathfinder_spike() -> void:
diff --git a/scenes/world/world.tscn b/scenes/world/world.tscn
index d39c503..85f848b 100644
--- a/scenes/world/world.tscn
+++ b/scenes/world/world.tscn
@@ -19,6 +19,9 @@
 y_sort_enabled = true
 script = ExtResource("1_world")
 
+[node name="DarkOverlay" type="CanvasModulate" parent="."]
+color = Color(1, 1, 1, 1)
+
 [node name="Terrain" type="TileMapLayer" parent="."]
 z_index = 0