diff --git a/FlexLove.lua b/FlexLove.lua
index 946b1ab..27ca9fd 100644
--- a/FlexLove.lua
+++ b/FlexLove.lua
@@ -183,7 +183,7 @@ local fadeIn = FlexLove.Animation.fade(1.0, 0, 1)
 fadeIn:apply(element)
 
 -- Scale animation
-local scaleUp = FlexLove.Animation.scale(0.5, 
+local scaleUp = FlexLove.Animation.scale(0.5,
   { width = 100, height = 50 },
   { width = 200, height = 100 }
 )
@@ -287,18 +287,30 @@ end
 function Color.fromHex(hexWithTag)
   local hex = hexWithTag:gsub("#", "")
   if #hex == 6 then
-    local r = tonumber("0x" .. hex:sub(1, 2)) or 0
-    local g = tonumber("0x" .. hex:sub(3, 4)) or 0
-    local b = tonumber("0x" .. hex:sub(5, 6)) or 0
+    local r = tonumber("0x" .. hex:sub(1, 2))
+    local g = tonumber("0x" .. hex:sub(3, 4))
+    local b = tonumber("0x" .. hex:sub(5, 6))
+    if not r or not g or not b then
+      error(
+        formatError("Color", string.format("Invalid hex string format: '%s'. Contains invalid hex digits", hexWithTag))
+      )
+    end
     return Color.new(r, g, b, 1)
   elseif #hex == 8 then
-    local r = tonumber("0x" .. hex:sub(1, 2)) or 0
-    local g = tonumber("0x" .. hex:sub(3, 4)) or 0
-    local b = tonumber("0x" .. hex:sub(5, 6)) or 0
-    local a = tonumber("0x" .. hex:sub(7, 8)) / 255
-    return Color.new(r, g, b, a)
+    local r = tonumber("0x" .. hex:sub(1, 2))
+    local g = tonumber("0x" .. hex:sub(3, 4))
+    local b = tonumber("0x" .. hex:sub(5, 6))
+    local a = tonumber("0x" .. hex:sub(7, 8))
+    if not r or not g or not b or not a then
+      error(
+        formatError("Color", string.format("Invalid hex string format: '%s'. Contains invalid hex digits", hexWithTag))
+      )
+    end
+    return Color.new(r, g, b, a / 255)
   else
-    error(formatError("Color", string.format("Invalid hex string format: '%s'. Expected #RRGGBB or #RRGGBBAA", hexWithTag)))
+    error(
+      formatError("Color", string.format("Invalid hex string format: '%s'. Expected #RRGGBB or #RRGGBBAA", hexWithTag))
+    )
   end
 end
 
@@ -399,7 +411,7 @@ local function safeLoadImage(imagePath)
   local success, result = pcall(function()
     return love.graphics.newImage(imagePath)
   end)
-  
+
   if success then
     return result, nil
   else
@@ -419,27 +431,27 @@ local function validateThemeDefinition(definition)
   if not definition then
     return false, "Theme definition is nil"
   end
-  
+
   if type(definition) ~= "table" then
     return false, "Theme definition must be a table"
   end
-  
+
   if not definition.name or type(definition.name) ~= "string" then
     return false, "Theme must have a 'name' field (string)"
   end
-  
+
   if definition.components and type(definition.components) ~= "table" then
     return false, "Theme 'components' must be a table"
   end
-  
+
   if definition.colors and type(definition.colors) ~= "table" then
     return false, "Theme 'colors' must be a table"
   end
-  
+
   if definition.fonts and type(definition.fonts) ~= "table" then
     return false, "Theme 'fonts' must be a table"
   end
-  
+
   return true, nil
 end
 
@@ -449,7 +461,7 @@ function Theme.new(definition)
   if not valid then
     error("[FlexLove] Invalid theme definition: " .. tostring(err))
   end
-  
+
   local self = setmetatable({}, Theme)
   self.name = definition.name
 
@@ -595,7 +607,7 @@ function Theme.getFont(fontName)
   if not activeTheme then
     return nil
   end
-  
+
   return activeTheme.fonts and activeTheme.fonts[fontName]
 end
 
@@ -606,7 +618,7 @@ function Theme.getColor(colorName)
   if not activeTheme then
     return nil
   end
-  
+
   return activeTheme.colors and activeTheme.colors[colorName]
 end
 
@@ -626,6 +638,43 @@ function Theme.getRegisteredThemes()
   return themeNames
 end
 
+--- Get all available color names from the active theme
+---@return table<string>|nil -- Array of color names, or nil if no theme active
+function Theme.getColorNames()
+  if not activeTheme or not activeTheme.colors then
+    return nil
+  end
+  
+  local colorNames = {}
+  for name, _ in pairs(activeTheme.colors) do
+    table.insert(colorNames, name)
+  end
+  return colorNames
+end
+
+--- Get all colors from the active theme
+---@return table<string, Color>|nil -- Table of all colors, or nil if no theme active
+function Theme.getAllColors()
+  if not activeTheme then
+    return nil
+  end
+  
+  return activeTheme.colors
+end
+
+--- Get a color with a fallback if not found
+---@param colorName string -- Name of the color to retrieve
+---@param fallback Color|nil -- Fallback color if not found (default: white)
+---@return Color -- The color or fallback
+function Theme.getColorOrDefault(colorName, fallback)
+  local color = Theme.getColor(colorName)
+  if color then
+    return color
+  end
+  
+  return fallback or Color.new(1, 1, 1, 1)
+end
+
 -- ====================
 -- Rounded Rectangle Helper
 -- ====================
@@ -1021,7 +1070,7 @@ function Units.getViewport()
   if Gui and Gui._cachedViewport and Gui._cachedViewport.width > 0 then
     return Gui._cachedViewport.width, Gui._cachedViewport.height
   end
-  
+
   -- Query viewport dimensions normally
   if love.graphics and love.graphics.getDimensions then
     return love.graphics.getDimensions()
@@ -1105,7 +1154,7 @@ function Units.isValid(unitStr)
   if type(unitStr) ~= "string" then
     return false
   end
-  
+
   local value, unit = Units.parse(unitStr)
   local validUnits = { px = true, ["%"] = true, vw = true, vh = true, ew = true, eh = true }
   return validUnits[unit] == true
@@ -1269,7 +1318,7 @@ local Gui = {
   baseScale = nil,
   scaleFactors = { x = 1.0, y = 1.0 },
   defaultTheme = nil,
-  _cachedViewport = { width = 0, height = 0 },  -- Cached viewport dimensions
+  _cachedViewport = { width = 0, height = 0 }, -- Cached viewport dimensions
 }
 
 --- Initialize FlexLove with configuration
@@ -1348,7 +1397,7 @@ end
 ---@return Element? -- Returns the topmost element or nil
 function Gui.getElementAtPosition(x, y)
   local candidates = {}
-  
+
   -- Recursively collect all elements that contain the point
   local function collectHits(element)
     -- Check if point is within element bounds
@@ -1356,30 +1405,30 @@ function Gui.getElementAtPosition(x, y)
     local by = element.y
     local bw = element._borderBoxWidth or (element.width + element.padding.left + element.padding.right)
     local bh = element._borderBoxHeight or (element.height + element.padding.top + element.padding.bottom)
-    
+
     if x >= bx and x <= bx + bw and y >= by and y <= by + bh then
       -- Only consider elements with callbacks (interactive elements)
       if element.callback and not element.disabled then
         table.insert(candidates, element)
       end
-      
+
       -- Check children
       for _, child in ipairs(element.children) do
         collectHits(child)
       end
     end
   end
-  
+
   -- Collect hits from all top-level elements
   for _, element in ipairs(Gui.topElements) do
     collectHits(element)
   end
-  
+
   -- Sort by z-index (highest first)
   table.sort(candidates, function(a, b)
     return a.z > b.z
   end)
-  
+
   -- Return the topmost element (highest z-index)
   return candidates[1]
 end
@@ -1388,15 +1437,15 @@ function Gui.update(dt)
   -- Reset event handling flags for new frame
   local mx, my = love.mouse.getPosition()
   local topElement = Gui.getElementAtPosition(mx, my)
-  
+
   -- Mark which element should handle events this frame
   Gui._activeEventElement = topElement
-  
+
   -- Update all elements
   for _, win in ipairs(Gui.topElements) do
     win:update(dt)
   end
-  
+
   -- Clear active element for next frame
   Gui._activeEventElement = nil
 end
@@ -1474,15 +1523,23 @@ end
 ---@field transition table?
 --- Easing functions for animations
 local Easing = {
-  linear = function(t) return t end,
-  
-  easeInQuad = function(t) return t * t end,
-  easeOutQuad = function(t) return t * (2 - t) end,
+  linear = function(t)
+    return t
+  end,
+
+  easeInQuad = function(t)
+    return t * t
+  end,
+  easeOutQuad = function(t)
+    return t * (2 - t)
+  end,
   easeInOutQuad = function(t)
     return t < 0.5 and 2 * t * t or -1 + (4 - 2 * t) * t
   end,
-  
-  easeInCubic = function(t) return t * t * t end,
+
+  easeInCubic = function(t)
+    return t * t * t
+  end,
   easeOutCubic = function(t)
     local t1 = t - 1
     return t1 * t1 * t1 + 1
@@ -1490,13 +1547,15 @@ local Easing = {
   easeInOutCubic = function(t)
     return t < 0.5 and 4 * t * t * t or (t - 1) * (2 * t - 2) * (2 * t - 2) + 1
   end,
-  
-  easeInQuart = function(t) return t * t * t * t end,
+
+  easeInQuart = function(t)
+    return t * t * t * t
+  end,
   easeOutQuart = function(t)
     local t1 = t - 1
     return 1 - t1 * t1 * t1 * t1
   end,
-  
+
   easeInExpo = function(t)
     return t == 0 and 0 or math.pow(2, 10 * (t - 1))
   end,
@@ -1536,15 +1595,15 @@ function Animation.new(props)
   self.transform = props.transform
   self.transition = props.transition
   self.elapsed = 0
-  
+
   -- Set easing function (default to linear)
   local easingName = props.easing or "linear"
   self.easing = Easing[easingName] or Easing.linear
-  
+
   -- Pre-allocate result table to avoid GC pressure
   self._cachedResult = {}
   self._resultDirty = true
-  
+
   return self
 end
 
@@ -1552,7 +1611,7 @@ end
 ---@return boolean
 function Animation:update(dt)
   self.elapsed = self.elapsed + dt
-  self._resultDirty = true  -- Mark cached result as dirty
+  self._resultDirty = true -- Mark cached result as dirty
   if self.elapsed >= self.duration then
     return true -- finished
   else
@@ -1566,10 +1625,10 @@ function Animation:interpolate()
   if not self._resultDirty then
     return self._cachedResult
   end
-  
+
   local t = math.min(self.elapsed / self.duration, 1)
-  t = self.easing(t)  -- Apply easing function
-  local result = self._cachedResult  -- Reuse existing table
+  t = self.easing(t) -- Apply easing function
+  local result = self._cachedResult -- Reuse existing table
 
   -- Clear previous values
   result.width = nil
@@ -1597,7 +1656,7 @@ function Animation:interpolate()
     end
   end
 
-  self._resultDirty = false  -- Mark as clean
+  self._resultDirty = false -- Mark as clean
   return result
 end
 
@@ -1643,8 +1702,8 @@ function Animation.scale(duration, fromScale, toScale)
 end
 
 local FONT_CACHE = {}
-local FONT_CACHE_MAX_SIZE = 50  -- Limit cache size to prevent unbounded growth
-local FONT_CACHE_ORDER = {}     -- Track access order for LRU eviction
+local FONT_CACHE_MAX_SIZE = 50 -- Limit cache size to prevent unbounded growth
+local FONT_CACHE_ORDER = {} -- Track access order for LRU eviction
 
 --- Create or get a font from cache
 ---@param size number
@@ -1671,10 +1730,10 @@ function FONT_CACHE.get(size, fontPath)
       -- Load default font
       FONT_CACHE[cacheKey] = love.graphics.newFont(size)
     end
-    
+
     -- Add to access order for LRU tracking
     table.insert(FONT_CACHE_ORDER, cacheKey)
-    
+
     -- Evict oldest entry if cache is full (LRU eviction)
     if #FONT_CACHE_ORDER > FONT_CACHE_MAX_SIZE then
       local oldestKey = table.remove(FONT_CACHE_ORDER, 1)
@@ -2159,7 +2218,11 @@ function Element.new(props)
   -- First, resolve padding using temporary dimensions
   -- For auto-sized elements, this is content width; for explicit sizing, this is border-box width
   local tempPadding = Units.resolveSpacing(props.padding, self.width, self.height)
-  self.margin = Units.resolveSpacing(props.margin, self.width, self.height)
+
+  -- Margin percentages are relative to parent's dimensions (CSS spec)
+  local parentWidth = self.parent and self.parent.width or viewportWidth
+  local parentHeight = self.parent and self.parent.height or viewportHeight
+  self.margin = Units.resolveSpacing(props.margin, parentWidth, parentHeight)
 
   -- For auto-sized elements, add padding to get border-box dimensions
   if self.autosizing.width then
@@ -2878,16 +2941,13 @@ function Element:layoutChildren()
     elseif self.justifyContent == JustifyContent.SPACE_BETWEEN then
       startPos = 0
       if #line > 1 then
-        -- Gap already accounted for in freeSpace calculation
         itemSpacing = self.gap + (freeSpace / (#line - 1))
       end
     elseif self.justifyContent == JustifyContent.SPACE_AROUND then
-      -- Gap already accounted for in freeSpace calculation
       local spaceAroundEach = freeSpace / #line
       startPos = spaceAroundEach / 2
       itemSpacing = self.gap + spaceAroundEach
     elseif self.justifyContent == JustifyContent.SPACE_EVENLY then
-      -- Gap already accounted for in freeSpace calculation
       local spaceBetween = freeSpace / (#line + 1)
       startPos = spaceBetween
       itemSpacing = self.gap + spaceBetween
@@ -2923,9 +2983,12 @@ function Element:layoutChildren()
         elseif effectiveAlign == AlignItems.FLEX_END then
           child.y = self.y + self.padding.top + reservedCrossStart + currentCrossPos + lineHeight - childBorderBoxHeight
         elseif effectiveAlign == AlignItems.STRETCH then
-          -- STRETCH: Set border-box height to lineHeight, content area shrinks to fit
-          child._borderBoxHeight = lineHeight
-          child.height = math.max(0, lineHeight - child.padding.top - child.padding.bottom)
+          -- STRETCH: Only apply if height was not explicitly set
+          if child.autosizing and child.autosizing.height then
+            -- STRETCH: Set border-box height to lineHeight, content area shrinks to fit
+            child._borderBoxHeight = lineHeight
+            child.height = math.max(0, lineHeight - child.padding.top - child.padding.bottom)
+          end
           child.y = self.y + self.padding.top + reservedCrossStart + currentCrossPos
         end
 
@@ -2964,9 +3027,12 @@ function Element:layoutChildren()
         elseif effectiveAlign == AlignItems.FLEX_END then
           child.x = self.x + self.padding.left + reservedCrossStart + currentCrossPos + lineHeight - childBorderBoxWidth
         elseif effectiveAlign == AlignItems.STRETCH then
-          -- STRETCH: Set border-box width to lineHeight, content area shrinks to fit
-          child._borderBoxWidth = lineHeight
-          child.width = math.max(0, lineHeight - child.padding.left - child.padding.right)
+          -- STRETCH: Only apply if width was not explicitly set
+          if child.autosizing and child.autosizing.width then
+            -- STRETCH: Set border-box width to lineHeight, content area shrinks to fit
+            child._borderBoxWidth = lineHeight
+            child.width = math.max(0, lineHeight - child.padding.left - child.padding.right)
+          end
           child.x = self.x + self.padding.left + reservedCrossStart + currentCrossPos
         end
 
@@ -3023,7 +3089,7 @@ function Element:destroy()
 
   -- Clear animation reference
   self.animation = nil
-  
+
   -- Clear callback to prevent closure leaks
   self.callback = nil
 end
@@ -3034,7 +3100,7 @@ function Element:draw()
   if self.opacity <= 0 then
     return
   end
-  
+
   -- Handle opacity during animation
   local drawBackgroundColor = self.backgroundColor
   if self.animation then
@@ -3048,7 +3114,7 @@ function Element:draw()
   -- Cache border box dimensions for this draw call (optimization)
   local borderBoxWidth = self._borderBoxWidth or (self.width + self.padding.left + self.padding.right)
   local borderBoxHeight = self._borderBoxHeight or (self.height + self.padding.top + self.padding.bottom)
-  
+
   -- LAYER 1: Draw backgroundColor first (behind everything)
   -- Apply opacity to all drawing operations
   -- (x, y) represents border box, so draw background from (x, y)
@@ -3056,14 +3122,7 @@ function Element:draw()
   local backgroundWithOpacity =
     Color.new(drawBackgroundColor.r, drawBackgroundColor.g, drawBackgroundColor.b, drawBackgroundColor.a * self.opacity)
   love.graphics.setColor(backgroundWithOpacity:toRGBA())
-  RoundedRect.draw(
-    "fill",
-    self.x,
-    self.y,
-    borderBoxWidth,
-    borderBoxHeight,
-    self.cornerRadius
-  )
+  RoundedRect.draw("fill", self.x, self.y, borderBoxWidth, borderBoxHeight, self.cornerRadius)
 
   -- LAYER 2: Draw theme on top of backgroundColor (if theme exists)
   if self.themeComponent then
@@ -3100,11 +3159,15 @@ function Element:draw()
 
         if atlasToUse and component.regions then
           -- Validate component has required structure
-          local hasAllRegions = component.regions.topLeft and component.regions.topCenter and 
-                                component.regions.topRight and component.regions.middleLeft and
-                                component.regions.middleCenter and component.regions.middleRight and
-                                component.regions.bottomLeft and component.regions.bottomCenter and
-                                component.regions.bottomRight
+          local hasAllRegions = component.regions.topLeft
+            and component.regions.topCenter
+            and component.regions.topRight
+            and component.regions.middleLeft
+            and component.regions.middleCenter
+            and component.regions.middleRight
+            and component.regions.bottomLeft
+            and component.regions.bottomCenter
+            and component.regions.bottomRight
           if hasAllRegions then
             NineSlice.draw(component, atlasToUse, self.x, self.y, self.width, self.height, self.padding, self.opacity)
           else
@@ -3659,7 +3722,7 @@ function Element:calculateTextWidth()
         fontPath = themeToUse.fonts.default
       end
     end
-    
+
     local tempFont = FONT_CACHE.get(self.textSize, fontPath)
     local width = tempFont:getWidth(self.text)
     return width
@@ -3692,7 +3755,7 @@ function Element:calculateTextHeight()
         fontPath = themeToUse.fonts.default
       end
     end
-    
+
     local tempFont = FONT_CACHE.get(self.textSize, fontPath)
     local height = tempFont:getHeight()
     return height
@@ -3710,19 +3773,34 @@ function Element:calculateAutoWidth()
     return contentWidth
   end
 
+  -- For HORIZONTAL flex: sum children widths + gaps
+  -- For VERTICAL flex: max of children widths
+  local isHorizontal = self.flexDirection == "horizontal"
   local totalWidth = contentWidth
+  local maxWidth = contentWidth
   local participatingChildren = 0
+
   for _, child in ipairs(self.children) do
     -- Skip explicitly absolute positioned children as they don't affect parent auto-sizing
     if not child._explicitlyAbsolute then
       -- BORDER-BOX MODEL: Use border-box width for auto-sizing calculations
       local childBorderBoxWidth = child:getBorderBoxWidth()
-      totalWidth = totalWidth + childBorderBoxWidth
+      if isHorizontal then
+        totalWidth = totalWidth + childBorderBoxWidth
+      else
+        maxWidth = math.max(maxWidth, childBorderBoxWidth)
+      end
       participatingChildren = participatingChildren + 1
     end
   end
 
-  return totalWidth + (self.gap * participatingChildren)
+  if isHorizontal then
+    -- Add gaps between children (n-1 gaps for n children)
+    local gapCount = math.max(0, participatingChildren - 1)
+    return totalWidth + (self.gap * gapCount)
+  else
+    return maxWidth
+  end
 end
 
 --- Calculate auto height based on children
@@ -3732,19 +3810,34 @@ function Element:calculateAutoHeight()
     return height
   end
 
+  -- For VERTICAL flex: sum children heights + gaps
+  -- For HORIZONTAL flex: max of children heights
+  local isVertical = self.flexDirection == "vertical"
   local totalHeight = height
+  local maxHeight = height
   local participatingChildren = 0
+
   for _, child in ipairs(self.children) do
     -- Skip explicitly absolute positioned children as they don't affect parent auto-sizing
     if not child._explicitlyAbsolute then
       -- BORDER-BOX MODEL: Use border-box height for auto-sizing calculations
       local childBorderBoxHeight = child:getBorderBoxHeight()
-      totalHeight = totalHeight + childBorderBoxHeight
+      if isVertical then
+        totalHeight = totalHeight + childBorderBoxHeight
+      else
+        maxHeight = math.max(maxHeight, childBorderBoxHeight)
+      end
       participatingChildren = participatingChildren + 1
     end
   end
 
-  return totalHeight + (self.gap * participatingChildren)
+  if isVertical then
+    -- Add gaps between children (n-1 gaps for n children)
+    local gapCount = math.max(0, participatingChildren - 1)
+    return totalHeight + (self.gap * gapCount)
+  else
+    return maxHeight
+  end
 end
 
 ---@param newText string
@@ -3769,4 +3862,23 @@ Gui.new = Element.new
 Gui.Element = Element
 Gui.Animation = Animation
 Gui.Theme = Theme
-return { GUI = Gui, Gui = Gui, Element = Element, Color = Color, Theme = Theme, Animation = Animation, enums = enums }
+
+-- Export individual enums for convenience
+return {
+  GUI = Gui,
+  Gui = Gui,
+  Element = Element,
+  Color = Color,
+  Theme = Theme,
+  Animation = Animation,
+  enums = enums,
+  -- Export individual enums at top level
+  Positioning = Positioning,
+  FlexDirection = FlexDirection,
+  JustifyContent = JustifyContent,
+  AlignItems = AlignItems,
+  AlignSelf = AlignSelf,
+  AlignContent = AlignContent,
+  FlexWrap = FlexWrap,
+  TextAlign = TextAlign,
+}
diff --git a/examples/ThemeColorAccessDemo.lua b/examples/ThemeColorAccessDemo.lua
new file mode 100644
index 0000000..022f532
--- /dev/null
+++ b/examples/ThemeColorAccessDemo.lua
@@ -0,0 +1,170 @@
+-- Theme Color Access Demo
+-- Demonstrates various ways to access and use theme colors
+
+package.path = package.path .. ";./?.lua;../?.lua"
+
+local FlexLove = require("FlexLove")
+local Theme = FlexLove.Theme
+local Gui = FlexLove.Gui
+local Color = FlexLove.Color
+
+-- Initialize love stubs for testing
+love = {
+  graphics = {
+    newFont = function(size) return { getHeight = function() return size end } end,
+    getFont = function() return { getHeight = function() return 12 end } end,
+    getWidth = function() return 1920 end,
+    getHeight = function() return 1080 end,
+    newImage = function() return {} end,
+    newQuad = function() return {} end,
+  },
+}
+
+print("=== Theme Color Access Demo ===\n")
+
+-- Load and activate the space theme
+Theme.load("space")
+Theme.setActive("space")
+
+print("1. Basic Color Access")
+print("---------------------")
+
+-- Method 1: Using Theme.getColor() (Recommended)
+local primaryColor = Theme.getColor("primary")
+local secondaryColor = Theme.getColor("secondary")
+local textColor = Theme.getColor("text")
+local textDarkColor = Theme.getColor("textDark")
+
+print(string.format("Primary: r=%.2f, g=%.2f, b=%.2f", primaryColor.r, primaryColor.g, primaryColor.b))
+print(string.format("Secondary: r=%.2f, g=%.2f, b=%.2f", secondaryColor.r, secondaryColor.g, secondaryColor.b))
+print(string.format("Text: r=%.2f, g=%.2f, b=%.2f", textColor.r, textColor.g, textColor.b))
+print(string.format("Text Dark: r=%.2f, g=%.2f, b=%.2f", textDarkColor.r, textDarkColor.g, textDarkColor.b))
+
+print("\n2. Get All Available Colors")
+print("----------------------------")
+
+-- Method 2: Get all color names
+local colorNames = Theme.getColorNames()
+if colorNames then
+  print("Available colors in theme:")
+  for _, name in ipairs(colorNames) do
+    print("  - " .. name)
+  end
+end
+
+print("\n3. Get All Colors at Once")
+print("-------------------------")
+
+-- Method 3: Get all colors as a table
+local allColors = Theme.getAllColors()
+if allColors then
+  print("All colors:")
+  for name, color in pairs(allColors) do
+    print(string.format("  %s: r=%.2f, g=%.2f, b=%.2f, a=%.2f", name, color.r, color.g, color.b, color.a))
+  end
+end
+
+print("\n4. Safe Color Access with Fallback")
+print("-----------------------------------")
+
+-- Method 4: Get color with fallback
+local accentColor = Theme.getColorOrDefault("accent", Color.new(1, 0, 0, 1)) -- Falls back to red
+local primaryColor2 = Theme.getColorOrDefault("primary", Color.new(1, 0, 0, 1)) -- Uses theme color
+
+print(string.format("Accent (fallback): r=%.2f, g=%.2f, b=%.2f", accentColor.r, accentColor.g, accentColor.b))
+print(string.format("Primary (theme): r=%.2f, g=%.2f, b=%.2f", primaryColor2.r, primaryColor2.g, primaryColor2.b))
+
+print("\n5. Using Colors in GUI Elements")
+print("--------------------------------")
+
+-- Create a container with theme colors
+local container = Gui.new({
+  width = 400,
+  height = 300,
+  backgroundColor = Theme.getColor("secondary"),
+  positioning = FlexLove.enums.Positioning.FLEX,
+  flexDirection = FlexLove.enums.FlexDirection.VERTICAL,
+  gap = 10,
+  padding = { top = 20, right = 20, bottom = 20, left = 20 },
+})
+
+-- Create a button with primary color
+local button = Gui.new({
+  parent = container,
+  width = 360,
+  height = 50,
+  backgroundColor = Theme.getColor("primary"),
+  textColor = Theme.getColor("text"),
+  text = "Click Me!",
+  textSize = 18,
+})
+
+-- Create a text label with dark text
+local label = Gui.new({
+  parent = container,
+  width = 360,
+  height = 30,
+  backgroundColor = Theme.getColorOrDefault("background", Color.new(0.2, 0.2, 0.2, 1)),
+  textColor = Theme.getColor("textDark"),
+  text = "This is a label with dark text",
+  textSize = 14,
+})
+
+print("Created GUI elements with theme colors:")
+print(string.format("  Container: %d children", #container.children))
+print(string.format("  Button background: r=%.2f, g=%.2f, b=%.2f", button.backgroundColor.r, button.backgroundColor.g, button.backgroundColor.b))
+print(string.format("  Label text color: r=%.2f, g=%.2f, b=%.2f", label.textColor.r, label.textColor.g, label.textColor.b))
+
+print("\n6. Creating Color Variations")
+print("-----------------------------")
+
+-- Create variations of theme colors
+local primaryDark = Color.new(
+  primaryColor.r * 0.7,
+  primaryColor.g * 0.7,
+  primaryColor.b * 0.7,
+  primaryColor.a
+)
+
+local primaryLight = Color.new(
+  math.min(1, primaryColor.r * 1.3),
+  math.min(1, primaryColor.g * 1.3),
+  math.min(1, primaryColor.b * 1.3),
+  primaryColor.a
+)
+
+local primaryTransparent = Color.new(
+  primaryColor.r,
+  primaryColor.g,
+  primaryColor.b,
+  0.5
+)
+
+print(string.format("Primary (original): r=%.2f, g=%.2f, b=%.2f, a=%.2f", primaryColor.r, primaryColor.g, primaryColor.b, primaryColor.a))
+print(string.format("Primary (dark):     r=%.2f, g=%.2f, b=%.2f, a=%.2f", primaryDark.r, primaryDark.g, primaryDark.b, primaryDark.a))
+print(string.format("Primary (light):    r=%.2f, g=%.2f, b=%.2f, a=%.2f", primaryLight.r, primaryLight.g, primaryLight.b, primaryLight.a))
+print(string.format("Primary (50%% alpha): r=%.2f, g=%.2f, b=%.2f, a=%.2f", primaryTransparent.r, primaryTransparent.g, primaryTransparent.b, primaryTransparent.a))
+
+print("\n7. Quick Reference")
+print("------------------")
+print([[
+// Basic usage:
+local color = Theme.getColor("primary")
+
+// With fallback:
+local color = Theme.getColorOrDefault("accent", Color.new(1, 0, 0, 1))
+
+// Get all colors:
+local colors = Theme.getAllColors()
+
+// Get color names:
+local names = Theme.getColorNames()
+
+// Use in elements:
+local button = Gui.new({
+  backgroundColor = Theme.getColor("primary"),
+  textColor = Theme.getColor("text"),
+})
+]])
+
+print("\n=== Demo Complete ===")
diff --git a/examples/ThemeColorAccessSimple.lua b/examples/ThemeColorAccessSimple.lua
new file mode 100644
index 0000000..6519cdd
--- /dev/null
+++ b/examples/ThemeColorAccessSimple.lua
@@ -0,0 +1,181 @@
+-- Simple Theme Color Access Demo
+-- Shows how to access theme colors without creating GUI elements
+
+package.path = package.path .. ";./?.lua;../?.lua"
+
+local FlexLove = require("FlexLove")
+local Theme = FlexLove.Theme
+local Color = FlexLove.Color
+
+-- Initialize minimal love stubs
+love = {
+  graphics = {
+    newFont = function(size) return { getHeight = function() return size end } end,
+    newImage = function() return {} end,
+    newQuad = function() return {} end,
+  },
+}
+
+print("=== Theme Color Access - Simple Demo ===\n")
+
+-- Load and activate the space theme
+Theme.load("space")
+Theme.setActive("space")
+
+print("✓ Theme 'space' loaded and activated\n")
+
+-- ============================================
+-- METHOD 1: Basic Color Access (Recommended)
+-- ============================================
+print("METHOD 1: Theme.getColor(colorName)")
+print("------------------------------------")
+
+local primaryColor = Theme.getColor("primary")
+local secondaryColor = Theme.getColor("secondary")
+local textColor = Theme.getColor("text")
+local textDarkColor = Theme.getColor("textDark")
+
+print(string.format("primary   = Color(r=%.2f, g=%.2f, b=%.2f, a=%.2f)", 
+  primaryColor.r, primaryColor.g, primaryColor.b, primaryColor.a))
+print(string.format("secondary = Color(r=%.2f, g=%.2f, b=%.2f, a=%.2f)", 
+  secondaryColor.r, secondaryColor.g, secondaryColor.b, secondaryColor.a))
+print(string.format("text      = Color(r=%.2f, g=%.2f, b=%.2f, a=%.2f)", 
+  textColor.r, textColor.g, textColor.b, textColor.a))
+print(string.format("textDark  = Color(r=%.2f, g=%.2f, b=%.2f, a=%.2f)", 
+  textDarkColor.r, textDarkColor.g, textDarkColor.b, textDarkColor.a))
+
+-- ============================================
+-- METHOD 2: Get All Color Names
+-- ============================================
+print("\nMETHOD 2: Theme.getColorNames()")
+print("--------------------------------")
+
+local colorNames = Theme.getColorNames()
+print("Available colors:")
+for i, name in ipairs(colorNames) do
+  print(string.format("  %d. %s", i, name))
+end
+
+-- ============================================
+-- METHOD 3: Get All Colors at Once
+-- ============================================
+print("\nMETHOD 3: Theme.getAllColors()")
+print("-------------------------------")
+
+local allColors = Theme.getAllColors()
+print("All colors with values:")
+for name, color in pairs(allColors) do
+  print(string.format("  %-10s = (%.2f, %.2f, %.2f, %.2f)", 
+    name, color.r, color.g, color.b, color.a))
+end
+
+-- ============================================
+-- METHOD 4: Safe Access with Fallback
+-- ============================================
+print("\nMETHOD 4: Theme.getColorOrDefault(colorName, fallback)")
+print("-------------------------------------------------------")
+
+-- Try to get a color that exists
+local existingColor = Theme.getColorOrDefault("primary", Color.new(1, 0, 0, 1))
+print(string.format("Existing color 'primary': (%.2f, %.2f, %.2f) ✓", 
+  existingColor.r, existingColor.g, existingColor.b))
+
+-- Try to get a color that doesn't exist (will use fallback)
+local missingColor = Theme.getColorOrDefault("accent", Color.new(1, 0, 0, 1))
+print(string.format("Missing color 'accent' (fallback): (%.2f, %.2f, %.2f) ✓", 
+  missingColor.r, missingColor.g, missingColor.b))
+
+-- ============================================
+-- PRACTICAL EXAMPLES
+-- ============================================
+print("\n=== Practical Usage Examples ===\n")
+
+print("Example 1: Using colors in element creation")
+print("--------------------------------------------")
+print([[
+local button = Gui.new({
+  width = 200,
+  height = 50,
+  backgroundColor = Theme.getColor("primary"),
+  textColor = Theme.getColor("text"),
+  text = "Click Me!"
+})
+]])
+
+print("\nExample 2: Creating color variations")
+print("-------------------------------------")
+print([[
+local primary = Theme.getColor("primary")
+
+-- Darker version (70% brightness)
+local primaryDark = Color.new(
+  primary.r * 0.7,
+  primary.g * 0.7,
+  primary.b * 0.7,
+  primary.a
+)
+
+-- Lighter version (130% brightness)
+local primaryLight = Color.new(
+  math.min(1, primary.r * 1.3),
+  math.min(1, primary.g * 1.3),
+  math.min(1, primary.b * 1.3),
+  primary.a
+)
+
+-- Semi-transparent version
+local primaryTransparent = Color.new(
+  primary.r,
+  primary.g,
+  primary.b,
+  0.5  -- 50% opacity
+)
+]])
+
+print("\nExample 3: Safe color access")
+print("-----------------------------")
+print([[
+-- With fallback to white if color doesn't exist
+local bgColor = Theme.getColorOrDefault("background", Color.new(1, 1, 1, 1))
+
+-- With fallback to theme's secondary color
+local borderColor = Theme.getColorOrDefault(
+  "border", 
+  Theme.getColor("secondary")
+)
+]])
+
+print("\nExample 4: Dynamic color selection")
+print("-----------------------------------")
+print([[
+-- Get all available colors
+local colors = Theme.getAllColors()
+
+-- Pick a random color
+local colorNames = {}
+for name in pairs(colors) do
+  table.insert(colorNames, name)
+end
+local randomColorName = colorNames[math.random(#colorNames)]
+local randomColor = colors[randomColorName]
+]])
+
+print("\n=== Quick Reference ===\n")
+print("Theme.getColor(name)              -- Get a specific color")
+print("Theme.getColorOrDefault(n, fb)    -- Get color with fallback")
+print("Theme.getAllColors()              -- Get all colors as table")
+print("Theme.getColorNames()             -- Get array of color names")
+print("Theme.hasActive()                 -- Check if theme is active")
+print("Theme.getActive()                 -- Get active theme object")
+
+print("\n=== Available Colors in 'space' Theme ===\n")
+for i, name in ipairs(colorNames) do
+  local color = allColors[name]
+  print(string.format("%-10s  RGB(%.0f, %.0f, %.0f)", 
+    name, 
+    color.r * 255, 
+    color.g * 255, 
+    color.b * 255))
+end
+
+print("\n=== Demo Complete ===")
diff --git a/testing/__tests__/03_flex_direction_horizontal_tests.lua b/testing/__tests__/03_flex_direction_horizontal_tests.lua
index ce337ab..c78ded4 100644
--- a/testing/__tests__/03_flex_direction_horizontal_tests.lua
+++ b/testing/__tests__/03_flex_direction_horizontal_tests.lua
@@ -442,9 +442,9 @@ function TestHorizontalFlexDirection:testHorizontalLayoutAlignItemsStretch()
   parent:addChild(child1)
   parent:addChild(child2)
 
-  -- With align-items stretch in horizontal layout, children should stretch to parent height
-  luaunit.assertEquals(child1.height, parent.height)
-  luaunit.assertEquals(child2.height, parent.height)
+  -- With align-items stretch, children with explicit heights should keep them (CSS flexbox behavior)
+  luaunit.assertEquals(child1.height, 30)
+  luaunit.assertEquals(child2.height, 40)
 end
 
 -- Test 14: Horizontal layout with align-items center
diff --git a/testing/__tests__/04_flex_direction_vertical_tests.lua b/testing/__tests__/04_flex_direction_vertical_tests.lua
index 031b7c8..8343f5c 100644
--- a/testing/__tests__/04_flex_direction_vertical_tests.lua
+++ b/testing/__tests__/04_flex_direction_vertical_tests.lua
@@ -402,9 +402,9 @@ function TestVerticalFlexDirection:testVerticalLayoutAlignItemsStretch()
   parent:addChild(child1)
   parent:addChild(child2)
 
-  -- Children should be stretched to fill parent width
-  luaunit.assertEquals(child1.width, parent.width)
-  luaunit.assertEquals(child2.width, parent.width)
+  -- Children with explicit widths should keep them (CSS flexbox behavior)
+  luaunit.assertEquals(child1.width, 80)
+  luaunit.assertEquals(child2.width, 60)
 end
 
 -- Test 13: Vertical layout with space-between
diff --git a/testing/__tests__/06_align_items_tests.lua b/testing/__tests__/06_align_items_tests.lua
index e1269a6..e7455d6 100644
--- a/testing/__tests__/06_align_items_tests.lua
+++ b/testing/__tests__/06_align_items_tests.lua
@@ -189,11 +189,11 @@ function TestAlignItems:testHorizontalFlexAlignItemsStretch()
   container:addChild(child1)
   container:addChild(child2)
 
-  -- Children should be stretched to fill container height
+  -- Children with explicit heights should NOT be stretched (CSS flexbox behavior)
   luaunit.assertEquals(child1.y, 0)
   luaunit.assertEquals(child2.y, 0)
-  luaunit.assertEquals(child1.height, 100)
-  luaunit.assertEquals(child2.height, 100)
+  luaunit.assertEquals(child1.height, 30)  -- Keeps explicit height
+  luaunit.assertEquals(child2.height, 40)  -- Keeps explicit height
 end
 
 -- Test 5: Vertical Flex with AlignItems.FLEX_START
@@ -357,11 +357,11 @@ function TestAlignItems:testVerticalFlexAlignItemsStretch()
   container:addChild(child1)
   container:addChild(child2)
 
-  -- Children should be stretched to fill container width
+  -- Children with explicit widths should NOT be stretched (CSS flexbox behavior)
   luaunit.assertEquals(child1.x, 0)
   luaunit.assertEquals(child2.x, 0)
-  luaunit.assertEquals(child1.width, 200)
-  luaunit.assertEquals(child2.width, 200)
+  luaunit.assertEquals(child1.width, 50)  -- Keeps explicit width
+  luaunit.assertEquals(child2.width, 80)  -- Keeps explicit width
 end
 
 -- Test 9: Default AlignItems value (should be STRETCH)
@@ -386,9 +386,9 @@ function TestAlignItems:testDefaultAlignItems()
 
   container:addChild(child)
 
-  -- Default should be STRETCH
+  -- Default should be STRETCH, but explicit heights are respected
   luaunit.assertEquals(container.alignItems, AlignItems.STRETCH)
-  luaunit.assertEquals(child.height, 100) -- Should be stretched
+  luaunit.assertEquals(child.height, 30) -- Keeps explicit height (CSS flexbox behavior)
 end
 
 -- Test 10: AlignItems with mixed child sizes
diff --git a/testing/__tests__/07_flex_wrap_tests.lua b/testing/__tests__/07_flex_wrap_tests.lua
index 4bd3e00..d0ff319 100644
--- a/testing/__tests__/07_flex_wrap_tests.lua
+++ b/testing/__tests__/07_flex_wrap_tests.lua
@@ -280,12 +280,12 @@ function TestFlexWrap07_WrapWithStretchAlignItems()
 
   local positions = layoutAndGetPositions(container)
 
-  -- All children in first line should stretch to tallest (35)
-  luaunit.assertEquals(positions[1].height, 35) -- child1 stretched
-  luaunit.assertEquals(positions[2].height, 35) -- child2 keeps height
+  -- Children with explicit heights should keep them (CSS flexbox behavior)
+  luaunit.assertEquals(positions[1].height, 20) -- child1 keeps explicit height
+  luaunit.assertEquals(positions[2].height, 35) -- child2 keeps explicit height
 
-  -- Child in second line should keep its height (no other children to stretch to)
-  luaunit.assertEquals(positions[3].height, 25) -- child3 original height
+  -- Child in second line should keep its height
+  luaunit.assertEquals(positions[3].height, 25) -- child3 keeps explicit height
 
   -- Verify positions
   luaunit.assertEquals(positions[1].y, 0) -- First line
diff --git a/testing/__tests__/08_comprehensive_flex_tests.lua b/testing/__tests__/08_comprehensive_flex_tests.lua
index 1727097..9cd08cf 100644
--- a/testing/__tests__/08_comprehensive_flex_tests.lua
+++ b/testing/__tests__/08_comprehensive_flex_tests.lua
@@ -186,11 +186,11 @@ function TestComprehensiveFlex:testNestedFlexContainersComplexLayout()
   -- Positions are absolute including parent container position
   luaunit.assertEquals(inner2Positions[1].x, 20) -- parent x + 0
   luaunit.assertEquals(inner2Positions[1].y, 95) -- parent y + 0
-  luaunit.assertEquals(inner2Positions[1].height, 50) -- stretched to full container height
+  luaunit.assertEquals(inner2Positions[1].height, 25) -- explicit height, not stretched (CSS spec compliance)
 
   luaunit.assertEquals(inner2Positions[2].x, 60) -- parent x + 40
   luaunit.assertEquals(inner2Positions[2].y, 95) -- parent y + 0
-  luaunit.assertEquals(inner2Positions[2].height, 50) -- stretched to full container height
+  luaunit.assertEquals(inner2Positions[2].height, 25) -- explicit height, not stretched (CSS spec compliance)
 end
 
 -- Test 3: All flex properties combined with absolute positioning
@@ -390,19 +390,19 @@ function TestComprehensiveFlex:testDeeplyNestedFlexContainers()
   -- These positions are relative to level 1 container position
   luaunit.assertEquals(level2Positions[1].x, 20) -- positioned by level 1
   luaunit.assertEquals(level2Positions[1].y, 25) -- positioned by level 1
-  luaunit.assertEquals(level2Positions[1].height, 100) -- stretched to full cross-axis height
+  luaunit.assertEquals(level2Positions[1].height, 80) -- explicit height, not stretched (CSS spec compliance)
 
   luaunit.assertEquals(level2Positions[2].x, 110) -- positioned by level 1 + space-between
   luaunit.assertEquals(level2Positions[2].y, 25) -- positioned by level 1
-  luaunit.assertEquals(level2Positions[2].height, 100) -- stretched to full cross-axis height
+  luaunit.assertEquals(level2Positions[2].height, 80) -- explicit height, not stretched (CSS spec compliance)
 
   -- Level 3a: flex-end justification, center alignment
   -- Positions are absolute including parent positions
   luaunit.assertEquals(level3aPositions[1].x, 40) -- absolute position
-  luaunit.assertEquals(level3aPositions[1].y, 90) -- flex-end: positioned at bottom of stretched container
+  luaunit.assertEquals(level3aPositions[1].y, 70) -- flex-end: 25 (level2.y) + 45 (80 - 35 total children)
 
   luaunit.assertEquals(level3aPositions[2].x, 42.5) -- absolute position
-  luaunit.assertEquals(level3aPositions[2].y, 110) -- second item: 90 + 20 = 110
+  luaunit.assertEquals(level3aPositions[2].y, 90) -- second item: 70 + 20 = 90
 
   -- Level 3b: flex-start justification, flex-end alignment
   -- Positions are absolute including parent positions
@@ -1656,8 +1656,8 @@ function TestComprehensiveFlex:testComplexDashboardLayout()
     middlePositions[i] = { x = child.x, y = child.y, width = child.width, height = child.height }
   end
 
-  luaunit.assertEquals(middlePositions[1].x, 300) -- chart panel (300 + 20 padding)
-  luaunit.assertEquals(middlePositions[2].x, 1000) -- stats panel (300 + 680 + 20)
+  luaunit.assertEquals(middlePositions[1].x, 300) -- chart panel (280 sidebar + 20 padding)
+  luaunit.assertEquals(middlePositions[2].x, 1020) -- stats panel (280 + 20 + 680 + 40 gap with SPACE_BETWEEN)
 
   -- Test chart legend wrapping
   local chartPanel = middleContent.children[1]
@@ -1699,7 +1699,7 @@ function TestComprehensiveFlex:testComplexDashboardLayout()
   end
 
   luaunit.assertEquals(bottomPositions[1].x, 300) -- table panel
-  luaunit.assertEquals(bottomPositions[2].x, 860) -- right panels (300 + 540 + 20)
+  luaunit.assertEquals(bottomPositions[2].x, 880) -- right panels (280 + 20 + 540 + 40 gap with SPACE_BETWEEN)
 
   -- Test right panels layout
   local rightPanels = bottomContent.children[2]
@@ -1710,8 +1710,8 @@ function TestComprehensiveFlex:testComplexDashboardLayout()
     rightPositions[i] = { x = child.x, y = child.y, width = child.width, height = child.height }
   end
 
-  luaunit.assertEquals(rightPositions[1].x, 860) -- alerts panel
-  luaunit.assertEquals(rightPositions[2].x, 1120) -- progress panel (860 + 240 + 20)
+  luaunit.assertEquals(rightPositions[1].x, 880) -- alerts panel (same as parent due to SPACE_BETWEEN)
+  luaunit.assertEquals(rightPositions[2].x, 1140) -- progress panel (880 + 240 + 20)
 end
 
 luaunit.LuaUnit.run()
diff --git a/testing/__tests__/11_auxiliary_functions_tests.lua b/testing/__tests__/11_auxiliary_functions_tests.lua
index 0da8865..f78a48f 100644
--- a/testing/__tests__/11_auxiliary_functions_tests.lua
+++ b/testing/__tests__/11_auxiliary_functions_tests.lua
@@ -140,6 +140,7 @@ function TestAuxiliaryFunctions:testCalculateAutoWidthWithChildren()
   local parent = Gui.new({
     positioning = enums.Positioning.FLEX,
     flexDirection = enums.FlexDirection.HORIZONTAL,
+    gap = 5, -- Add gap to test gap calculation
   })
 
   local child1 = Gui.new({
@@ -172,6 +173,7 @@ function TestAuxiliaryFunctions:testCalculateAutoHeightWithChildren()
   local parent = Gui.new({
     positioning = enums.Positioning.FLEX,
     flexDirection = enums.FlexDirection.VERTICAL,
+    gap = 5, -- Add gap to test gap calculation
   })
 
   local child1 = Gui.new({
@@ -491,18 +493,21 @@ function TestAuxiliaryFunctions:testAnimationInterpolationAtBoundaries()
 
   -- At start (elapsed = 0)
   scaleAnim.elapsed = 0
+  scaleAnim._resultDirty = true  -- Mark dirty after changing elapsed
   local result = scaleAnim:interpolate()
   luaunit.assertEquals(result.width, 100)
   luaunit.assertEquals(result.height, 50)
 
   -- At end (elapsed = duration)
   scaleAnim.elapsed = 1.0
+  scaleAnim._resultDirty = true  -- Mark dirty after changing elapsed
   result = scaleAnim:interpolate()
   luaunit.assertEquals(result.width, 200)
   luaunit.assertEquals(result.height, 100)
 
   -- Beyond end (elapsed > duration) - should clamp to end values
   scaleAnim.elapsed = 1.5
+  scaleAnim._resultDirty = true  -- Mark dirty after changing elapsed
   result = scaleAnim:interpolate()
   luaunit.assertEquals(result.width, 200)
   luaunit.assertEquals(result.height, 100)
@@ -594,11 +599,11 @@ function TestAuxiliaryFunctions:testComplexColorManagementSystem()
   end
 
   -- Test color variations (opacity, brightness adjustments)
+  local opacities = { 0.1, 0.25, 0.5, 0.75, 0.9 }
   for color_name, color_set in pairs(theme_colors) do
     color_variations[color_name] = {}
 
     -- Create opacity variations
-    local opacities = { 0.1, 0.25, 0.5, 0.75, 0.9 }
     for _, opacity in ipairs(opacities) do
       local variant_color = Color.new(color_set.manual.r, color_set.manual.g, color_set.manual.b, opacity)
       color_variations[color_name]["alpha_" .. tostring(opacity)] = variant_color
@@ -678,7 +683,13 @@ function TestAuxiliaryFunctions:testComplexColorManagementSystem()
   ui_container:layoutChildren()
 
   luaunit.assertEquals(#ui_container.children, 5, "Should have 5 themed components")
-  luaunit.assertEquals(#theme_colors, 5, "Should have 5 base theme colors")
+  
+  -- Count theme_colors (it's a table with string keys, not an array)
+  local theme_color_count = 0
+  for _ in pairs(theme_colors) do
+    theme_color_count = theme_color_count + 1
+  end
+  luaunit.assertEquals(theme_color_count, 5, "Should have 5 base theme colors")
 
   local total_variations = 0
   for _, variations in pairs(color_variations) do
@@ -902,6 +913,7 @@ function TestAuxiliaryFunctions:testAdvancedTextAndAutoSizingSystem()
   table.insert(main_container.children, nested_container)
 
   -- Create nested structure with auto-sizing children
+  local prev_container = nested_container
   for level = 1, 3 do
     local level_container = Gui.new({
       width = 750 - (level * 50),
@@ -911,12 +923,9 @@ function TestAuxiliaryFunctions:testAdvancedTextAndAutoSizingSystem()
       justifyContent = enums.JustifyContent.SPACE_AROUND,
       gap = 5,
     })
-    level_container.parent = level == 1 and nested_container
-      or main_container.children[#main_container.children].children[level - 1]
-    table.insert(
-      (level == 1 and nested_container or main_container.children[#main_container.children].children[level - 1]).children,
-      level_container
-    )
+    level_container.parent = prev_container
+    table.insert(prev_container.children, level_container)
+    prev_container = level_container
 
     for item = 1, 4 do
       local item_text = string.format("L%d-Item%d: %s", level, item, string.rep("Text ", level))
@@ -943,7 +952,13 @@ function TestAuxiliaryFunctions:testAdvancedTextAndAutoSizingSystem()
     #text_scenarios + 1,
     "Should have scenario containers plus nested container"
   )
-  luaunit.assertTrue(#content_manager.text_metrics >= #text_scenarios, "Should have metrics for all scenarios")
+  
+  -- Count text_metrics (it's a table with string keys, not an array)
+  local metrics_count = 0
+  for _ in pairs(content_manager.text_metrics) do
+    metrics_count = metrics_count + 1
+  end
+  luaunit.assertTrue(metrics_count >= #text_scenarios, "Should have metrics for all scenarios")
 
   print(
     string.format(
@@ -1607,8 +1622,10 @@ function TestAuxiliaryFunctions:testAdvancedGUIManagementAndCleanup()
   end
 
   -- Test opacity management across hierarchy
-  for i, element_pair in pairs(managed_elements) do
-    if i % 2 == 0 then
+  for element_id, element_pair in pairs(managed_elements) do
+    -- Extract number from "element_N" key
+    local num = tonumber(element_id:match("%d+"))
+    if num and num % 2 == 0 then
       element_pair:updateOpacity(0.5)
       luaunit.assertEquals(element_pair.opacity, 0.5, "Even elements should have 0.5 opacity")
     end
diff --git a/testing/__tests__/12_units_system_tests.lua b/testing/__tests__/12_units_system_tests.lua
index aa283a2..8ce1927 100644
--- a/testing/__tests__/12_units_system_tests.lua
+++ b/testing/__tests__/12_units_system_tests.lua
@@ -22,6 +22,10 @@ end
 
 function TestUnitsSystem:tearDown()
   Gui.destroy()
+  -- Restore original viewport size
+  love.graphics.getDimensions = function()
+    return 800, 600
+  end
 end
 
 -- ============================================
@@ -245,7 +249,7 @@ function TestUnitsSystem:testMarginUnits()
   })
 
   luaunit.assertEquals(container.margin.top, 8) -- 8px
-  luaunit.assertEquals(container.margin.right, 12) -- 3% of 400
+  luaunit.assertEquals(container.margin.right, 36) -- 3% of viewport width (1200) - CSS spec: % margins relative to containing block
   luaunit.assertEquals(container.margin.bottom, 8) -- 1% of 800
   luaunit.assertEquals(container.margin.left, 24) -- 2% of 1200
 
diff --git a/testing/__tests__/16_event_system_tests.lua b/testing/__tests__/16_event_system_tests.lua
index 5ad23fe..51bf2bb 100644
--- a/testing/__tests__/16_event_system_tests.lua
+++ b/testing/__tests__/16_event_system_tests.lua
@@ -16,6 +16,7 @@ function TestEventSystem:setUp()
   -- Initialize GUI before each test
   Gui.init({ baseScale = { width = 1920, height = 1080 } })
   love.window.setMode(1920, 1080)
+  Gui.resize(1920, 1080) -- Recalculate scale factors after setMode
 end
 
 function TestEventSystem:tearDown()
diff --git a/testing/__tests__/19_negative_margin_tests.lua b/testing/__tests__/19_negative_margin_tests.lua
index a35e978..f3d4987 100644
--- a/testing/__tests__/19_negative_margin_tests.lua
+++ b/testing/__tests__/19_negative_margin_tests.lua
@@ -8,7 +8,7 @@ TestNegativeMargin = {}
 
 function TestNegativeMargin:setUp()
   FlexLove.Gui.destroy()
-  FlexLove.Gui.init({ baseScale = { width = 1920, height = 1080 } })
+  -- Don't call init to use 1:1 scaling (like other tests)
 end
 
 function TestNegativeMargin:tearDown()
diff --git a/testing/loveStub.lua b/testing/loveStub.lua
index 215e7a4..37d0971 100644
--- a/testing/loveStub.lua
+++ b/testing/loveStub.lua
@@ -88,12 +88,59 @@ end
 
 -- Mock mouse functions
 love_helper.mouse = {}
+
+-- Mock mouse state
+local mockMouseX = 0
+local mockMouseY = 0
+local mockMouseButtons = {} -- Table to track button states
+
 function love_helper.mouse.getPosition()
-  return 0, 0 -- Default position
+  return mockMouseX, mockMouseY
+end
+
+function love_helper.mouse.setPosition(x, y)
+  mockMouseX = x
+  mockMouseY = y
 end
 
 function love_helper.mouse.isDown(button)
-  return false -- Default not pressed
+  return mockMouseButtons[button] or false
+end
+
+function love_helper.mouse.setDown(button, isDown)
+  mockMouseButtons[button] = isDown
+end
+
+-- Mock timer functions
+love_helper.timer = {}
+
+-- Mock time state
+local mockTime = 0
+
+function love_helper.timer.getTime()
+  return mockTime
+end
+
+function love_helper.timer.setTime(time)
+  mockTime = time
+end
+
+function love_helper.timer.step(dt)
+  mockTime = mockTime + dt
+end
+
+-- Mock keyboard functions
+love_helper.keyboard = {}
+
+-- Mock keyboard state
+local mockKeyboardKeys = {} -- Table to track key states
+
+function love_helper.keyboard.isDown(key)
+  return mockKeyboardKeys[key] or false
+end
+
+function love_helper.keyboard.setDown(key, isDown)
+  mockKeyboardKeys[key] = isDown
 end
 
 -- Mock touch functions