diff --git a/src/App.tsx b/src/App.tsx
index 971cadc..0b14cf5 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -144,6 +144,8 @@ const MedPlanAssistant = () => {
           onAccept={handleAcceptDisclaimer}
           currentLanguage={currentLanguage}
           onLanguageChange={changeLanguage}
+          currentTheme={uiSettings.theme || 'system'}
+          onThemeChange={(theme: 'light' | 'dark' | 'system') => updateUiSetting('theme', theme)}
           t={t}
         />
 
@@ -166,162 +168,162 @@ const MedPlanAssistant = () => {
         <div className="max-w-7xl mx-auto">
           <header className="mb-8">
             <div className="flex justify-between items-start gap-4">
-            <div>
-              <h1 className="text-3xl md:text-4xl font-bold tracking-tight">{t('appTitle')}</h1>
+              <div className="">
+                <h1 className="text-3xl md:text-4xl font-bold tracking-tight">{t('appTitle')}</h1>
+              </div>
+              <div className="flex flex-wrap-reverse gap-2 justify-end">
+                <ThemeSelector
+                  currentTheme={uiSettings.theme || 'system'}
+                  onThemeChange={(theme: 'light' | 'dark' | 'system') => updateUiSetting('theme', theme)}
+                  t={t}
+                />
+                <LanguageSelector currentLanguage={currentLanguage} onLanguageChange={changeLanguage} t={t} />
+              </div>
             </div>
-            <div className="flex flex-wrap gap-2 justify-end">
-              <ThemeSelector
-                currentTheme={uiSettings.theme || 'system'}
-                onThemeChange={(theme: 'light' | 'dark' | 'system') => updateUiSetting('theme', theme)}
+            <p className="text-muted-foreground mt-1">{t('appSubtitle')}</p>
+          </header>
+
+          <div className="grid grid-cols-1 xl:grid-cols-2 gap-6">
+
+            {/* Both Columns - Chart */}
+            <div className={`xl:col-span-2 bg-card p-6 rounded-lg border min-h-[600px] flex flex-col ${uiSettings.stickyChart ? 'sticky top-2 z-30 shadow-lg' : ''}`}
+                style={uiSettings.stickyChart ? { borderColor: 'hsl(var(--primary))' } : {}}>
+              <div className="flex flex-wrap items-center gap-3 justify-between mb-4">
+                <div className="flex flex-wrap justify-center gap-2">
+                  <Tooltip>
+                    <TooltipTrigger asChild>
+                      <Button
+                        onClick={() => updateUiSetting('chartView', 'damph')}
+                        variant={chartView === 'damph' ? 'default' : 'secondary'}
+                      >
+                        {t(useCompactButtons ? 'dAmphetamineShort' : 'dAmphetamine')}
+                      </Button>
+                    </TooltipTrigger>
+                    <TooltipContent>
+                      <p className="text-xs max-w-xs">{t('chartViewDamphTooltip')}</p>
+                    </TooltipContent>
+                  </Tooltip>
+                  <Tooltip>
+                    <TooltipTrigger asChild>
+                      <Button
+                        onClick={() => updateUiSetting('chartView', 'ldx')}
+                        variant={chartView === 'ldx' ? 'default' : 'secondary'}
+                      >
+                        {t(useCompactButtons ? 'lisdexamfetamineShort' : 'lisdexamfetamine')}
+                      </Button>
+                    </TooltipTrigger>
+                    <TooltipContent>
+                      <p className="text-xs max-w-xs">{t('chartViewLdxTooltip')}</p>
+                    </TooltipContent>
+                  </Tooltip>
+                  <Tooltip>
+                    <TooltipTrigger asChild>
+                      <Button
+                        onClick={() => updateUiSetting('chartView', 'both')}
+                        variant={chartView === 'both' ? 'default' : 'secondary'}
+                      >
+                        {t('both')}
+                      </Button>
+                    </TooltipTrigger>
+                    <TooltipContent>
+                      <p className="text-xs max-w-xs">{t('chartViewBothTooltip')}</p>
+                    </TooltipContent>
+                  </Tooltip>
+                </div>
+                <IconButtonWithTooltip
+                  onClick={() => updateUiSetting('stickyChart', !uiSettings.stickyChart)}
+                  icon={uiSettings.stickyChart ? <Pin size={16} /> : <PinOff size={16} />}
+                  tooltip={uiSettings.stickyChart ? t('unpinChart') : t('pinChart')}
+                  variant={uiSettings.stickyChart ? 'default' : 'outline'}
+                  size="sm"
+                  className="shrink-0"
+                />
+              </div>
+
+              <SimulationChart
+                combinedProfile={combinedProfile}
+                templateProfile={showTemplateDay ? templateProfile : null}
+                chartView={chartView}
+                showDayTimeOnXAxis={showDayTimeOnXAxis}
+                showDayReferenceLines={showDayReferenceLines}
+                showTherapeuticRange={uiSettings.showTherapeuticRange ?? true}
+                therapeuticRange={therapeuticRange}
+                simulationDays={simulationDays}
+                displayedDays={displayedDays}
+                yAxisMin={yAxisMin}
+                yAxisMax={yAxisMax}
+                days={days}
                 t={t}
               />
-              <LanguageSelector currentLanguage={currentLanguage} onLanguageChange={changeLanguage} t={t} />
             </div>
-          </div>
-          <p className="text-muted-foreground mt-1">{t('appSubtitle')}</p>
-        </header>
 
-        <div className="grid grid-cols-1 xl:grid-cols-2 gap-6">
-
-          {/* Both Columns - Chart */}
-          <div className={`xl:col-span-2 bg-card p-6 rounded-lg border min-h-[600px] flex flex-col ${uiSettings.stickyChart ? 'sticky top-2 z-30 shadow-lg' : ''}`}
-               style={uiSettings.stickyChart ? { borderColor: 'hsl(var(--primary))' } : {}}>
-            <div className="flex flex-wrap items-center gap-3 justify-between mb-4">
-              <div className="flex flex-wrap justify-center gap-2">
-                <Tooltip>
-                  <TooltipTrigger asChild>
-                    <Button
-                      onClick={() => updateUiSetting('chartView', 'damph')}
-                      variant={chartView === 'damph' ? 'default' : 'secondary'}
-                    >
-                      {t(useCompactButtons ? 'dAmphetamineShort' : 'dAmphetamine')}
-                    </Button>
-                  </TooltipTrigger>
-                  <TooltipContent>
-                    <p className="text-xs max-w-xs">{t('chartViewDamphTooltip')}</p>
-                  </TooltipContent>
-                </Tooltip>
-                <Tooltip>
-                  <TooltipTrigger asChild>
-                    <Button
-                      onClick={() => updateUiSetting('chartView', 'ldx')}
-                      variant={chartView === 'ldx' ? 'default' : 'secondary'}
-                    >
-                      {t(useCompactButtons ? 'lisdexamfetamineShort' : 'lisdexamfetamine')}
-                    </Button>
-                  </TooltipTrigger>
-                  <TooltipContent>
-                    <p className="text-xs max-w-xs">{t('chartViewLdxTooltip')}</p>
-                  </TooltipContent>
-                </Tooltip>
-                <Tooltip>
-                  <TooltipTrigger asChild>
-                    <Button
-                      onClick={() => updateUiSetting('chartView', 'both')}
-                      variant={chartView === 'both' ? 'default' : 'secondary'}
-                    >
-                      {t('both')}
-                    </Button>
-                  </TooltipTrigger>
-                  <TooltipContent>
-                    <p className="text-xs max-w-xs">{t('chartViewBothTooltip')}</p>
-                  </TooltipContent>
-                </Tooltip>
-              </div>
-              <IconButtonWithTooltip
-                onClick={() => updateUiSetting('stickyChart', !uiSettings.stickyChart)}
-                icon={uiSettings.stickyChart ? <Pin size={16} /> : <PinOff size={16} />}
-                tooltip={uiSettings.stickyChart ? t('unpinChart') : t('pinChart')}
-                variant={uiSettings.stickyChart ? 'default' : 'outline'}
-                size="sm"
-                className="shrink-0"
+            {/* Left Column - Controls */}
+            <div className="xl:col-span-1 space-y-6">
+              <DaySchedule
+                days={days}
+                doseIncrement={doseIncrement}
+                onAddDay={addDay}
+                onRemoveDay={removeDay}
+                onAddDose={addDoseToDay}
+                onRemoveDose={removeDoseFromDay}
+                onUpdateDose={updateDoseInDay}
+                onUpdateDoseField={updateDoseFieldInDay}
+                onSortDoses={sortDosesInDay}
+                t={t}
               />
             </div>
 
-            <SimulationChart
-              combinedProfile={combinedProfile}
-              templateProfile={showTemplateDay ? templateProfile : null}
-              chartView={chartView}
-              showDayTimeOnXAxis={showDayTimeOnXAxis}
-              showDayReferenceLines={showDayReferenceLines}
-              showTherapeuticRange={uiSettings.showTherapeuticRange ?? true}
-              therapeuticRange={therapeuticRange}
-              simulationDays={simulationDays}
-              displayedDays={displayedDays}
-              yAxisMin={yAxisMin}
-              yAxisMax={yAxisMax}
-              days={days}
-              t={t}
-            />
-          </div>
-
-          {/* Left Column - Controls */}
-          <div className="xl:col-span-1 space-y-6">
-            <DaySchedule
-              days={days}
-              doseIncrement={doseIncrement}
-              onAddDay={addDay}
-              onRemoveDay={removeDay}
-              onAddDose={addDoseToDay}
-              onRemoveDose={removeDoseFromDay}
-              onUpdateDose={updateDoseInDay}
-              onUpdateDoseField={updateDoseFieldInDay}
-              onSortDoses={sortDosesInDay}
-              t={t}
-            />
-          </div>
-
-         {/* Right Column - Settings */}
-          <div className="xl:col-span-1 space-y-6">
-            <Settings
-              pkParams={pkParams}
-              therapeuticRange={therapeuticRange}
-              uiSettings={uiSettings}
-              days={days}
-              doseIncrement={doseIncrement}
-              onUpdatePkParams={(key: any, value: any) => updateNestedState('pkParams', key, value)}
-              onUpdateTherapeuticRange={(key: any, value: any) => updateNestedState('therapeuticRange', key, value)}
-              onUpdateUiSetting={updateUiSetting}
-              onReset={handleReset}
-              onImportDays={(importedDays: any) => updateState('days', importedDays)}
-              onOpenDataManagement={() => setShowDataManagement(true)}
-              t={t}
-            />
-          </div>
-
-        </div>
-
-        <footer className="mt-8 p-4 bg-muted rounded-lg text-sm text-muted-foreground border">
-          <div className="space-y-3">
-            <div>
-              <h3 className="font-semibold mb-2 text-foreground">{t('importantNote')}</h3>
-              <p>{t('disclaimer')}</p>
+          {/* Right Column - Settings */}
+            <div className="xl:col-span-1 space-y-6">
+              <Settings
+                pkParams={pkParams}
+                therapeuticRange={therapeuticRange}
+                uiSettings={uiSettings}
+                days={days}
+                doseIncrement={doseIncrement}
+                onUpdatePkParams={(key: any, value: any) => updateNestedState('pkParams', key, value)}
+                onUpdateTherapeuticRange={(key: any, value: any) => updateNestedState('therapeuticRange', key, value)}
+                onUpdateUiSetting={updateUiSetting}
+                onReset={handleReset}
+                onImportDays={(importedDays: any) => updateState('days', importedDays)}
+                onOpenDataManagement={() => setShowDataManagement(true)}
+                t={t}
+              />
             </div>
-            <div className="flex items-center justify-between">
-              <Button
-                variant="outline"
-                size="sm"
-                onClick={handleOpenDisclaimer}
-              >
-                {t('disclaimerModalFooterLink')}
-              </Button>
-              <div className="flex items-center gap-3">
-                <span className="text-xs text-muted-foreground" title={`Version: ${APP_VERSION}${APP_VERSION.endsWith('-dirty') ? ' (uncommitted changes)' : ''}`}>
-                  v{APP_VERSION}
-                </span>
-                <a
-                  href={PROJECT_REPOSITORY_URL}
-                  target="_blank"
-                  rel="noopener noreferrer"
-                  className="inline-flex items-center justify-center w-8 h-8 rounded-md hover:bg-accent text-foreground hover:text-accent-foreground transition-colors"
-                  title={t('footerProjectRepo')}
+
+          </div>
+
+          <footer className="mt-8 p-4 bg-muted rounded-lg text-sm text-muted-foreground border">
+            <div className="space-y-3">
+              <div>
+                <h3 className="font-semibold mb-2 text-foreground">{t('importantNote')}</h3>
+                <p>{t('disclaimer')}</p>
+              </div>
+              <div className="flex items-center justify-between">
+                <Button
+                  variant="outline"
+                  size="sm"
+                  onClick={handleOpenDisclaimer}
                 >
-                  <GitBranch size={18} />
-                </a>
+                  {t('disclaimerModalFooterLink')}
+                </Button>
+                <div className="flex items-center gap-3">
+                  <span className="text-xs text-muted-foreground" title={`Version: ${APP_VERSION}${APP_VERSION.endsWith('-dirty') ? ' (uncommitted changes)' : ''}`}>
+                    v{APP_VERSION}
+                  </span>
+                  <a
+                    href={PROJECT_REPOSITORY_URL}
+                    target="_blank"
+                    rel="noopener noreferrer"
+                    className="inline-flex items-center justify-center w-8 h-8 rounded-md hover:bg-accent text-foreground hover:text-accent-foreground transition-colors"
+                    title={t('footerProjectRepo')}
+                  >
+                    <GitBranch size={18} />
+                  </a>
+                </div>
               </div>
             </div>
-          </div>
-        </footer>
+          </footer>
         </div>
       </div>
     </TooltipProvider>
diff --git a/src/components/day-schedule.tsx b/src/components/day-schedule.tsx
index 49234b7..cb5fe9c 100644
--- a/src/components/day-schedule.tsx
+++ b/src/components/day-schedule.tsx
@@ -152,7 +152,7 @@ const DaySchedule: React.FC<DayScheduleProps> = ({
                   >
                     <Badge
                       variant="outline"
-                      className={`text-xs ${doseCountDiff > 0 ? 'bg-blue-50' : 'bg-orange-50'}`}
+                      className={`text-xs ${doseCountDiff > 0 ? 'bg-blue-100 dark:bg-blue-900/40 dark:text-blue-200' : 'bg-orange-100 dark:bg-orange-900/40 dark:text-orange-200'}`}
                     >
                       {doseCountDiff > 0 ? <TrendingUp className="h-3 w-3 inline mr-1" /> : <TrendingDown className="h-3 w-3 inline mr-1" />}
                       {day.doses.length} {day.doses.length === 1 ? t('dose') : t('doses')}
@@ -179,7 +179,7 @@ const DaySchedule: React.FC<DayScheduleProps> = ({
                   >
                     <Badge
                       variant="outline"
-                      className={`text-xs ${totalMgDiff > 0 ? 'bg-blue-50' : 'bg-orange-50'}`}
+                      className={`text-xs ${totalMgDiff > 0 ? 'bg-blue-100 dark:bg-blue-900/40 dark:text-blue-200' : 'bg-orange-100 dark:bg-orange-900/40 dark:text-orange-200'}`}
                     >
                       {totalMgDiff > 0 ? <TrendingUp className="h-3 w-3 inline mr-1" /> : <TrendingDown className="h-3 w-3 inline mr-1" />}
                       {day.doses.reduce((sum, dose) => sum + (parseFloat(dose.ldx) || 0), 0).toFixed(1)} mg
diff --git a/src/components/disclaimer-modal.tsx b/src/components/disclaimer-modal.tsx
index 01fa92a..2c9d618 100644
--- a/src/components/disclaimer-modal.tsx
+++ b/src/components/disclaimer-modal.tsx
@@ -13,6 +13,7 @@ import React, { useState } from 'react';
 import { Button } from './ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from './ui/card';
 import LanguageSelector from './language-selector';
+import ThemeSelector from './theme-selector';
 import { PROJECT_REPOSITORY_URL } from '../constants/defaults';
 
 interface DisclaimerModalProps {
@@ -20,6 +21,8 @@ interface DisclaimerModalProps {
   onAccept: () => void;
   currentLanguage: string;
   onLanguageChange: (lang: string) => void;
+  currentTheme?: 'light' | 'dark' | 'system';
+  onThemeChange?: (theme: 'light' | 'dark' | 'system') => void;
   t: (key: string) => string;
 }
 
@@ -28,6 +31,8 @@ const DisclaimerModal: React.FC<DisclaimerModalProps> = ({
   onAccept,
   currentLanguage,
   onLanguageChange,
+  currentTheme = 'system',
+  onThemeChange,
   t
 }) => {
   const [sourcesExpanded, setSourcesExpanded] = useState(false);
@@ -44,15 +49,24 @@ const DisclaimerModal: React.FC<DisclaimerModalProps> = ({
                 <CardTitle className="text-2xl font-bold">
                   {t('disclaimerModalTitle')}
                 </CardTitle>
-                <p className="text-center text-muted-foreground mt-2">
+                <p className="text-left text-muted-foreground mt-2">
                   {t('disclaimerModalSubtitle')}
                 </p>
               </div>
-              <LanguageSelector
-                currentLanguage={currentLanguage}
-                onLanguageChange={onLanguageChange}
-                t={t}
-              />
+              <div className="flex flex-wrap-reverse gap-2 justify-end">
+                {onThemeChange && (
+                  <ThemeSelector
+                    currentTheme={currentTheme}
+                    onThemeChange={onThemeChange}
+                    t={t}
+                  />
+                )}
+                <LanguageSelector
+                  currentLanguage={currentLanguage}
+                  onLanguageChange={onLanguageChange}
+                  t={t}
+                />
+              </div>
             </div>
           </CardHeader>
           <CardContent className="space-y-6 pt-6">
diff --git a/src/components/simulation-chart.tsx b/src/components/simulation-chart.tsx
index 62f656c..5476785 100644
--- a/src/components/simulation-chart.tsx
+++ b/src/components/simulation-chart.tsx
@@ -327,12 +327,12 @@ const chartDomain = React.useMemo(() => {
               <UiTooltip>
                 <UiTooltipTrigger asChild>
                   <span
-                    className="px-1 py-0.5 rounded-sm bg-white text-black shadow-sm border border-muted truncate inline-block max-w-[100px]"
+                    className="px-1 py-0.5 rounded-sm bg-background text-foreground shadow-sm border border-border truncate inline-block max-w-[100px]"
                   >
                     {labelInfo.display}
                   </span>
                 </UiTooltipTrigger>
-                <UiTooltipContent className="bg-white text-black shadow-md border max-w-xs">
+                <UiTooltipContent className="bg-background text-foreground shadow-md border border-border max-w-xs">
                   <span className="font-medium">{labelInfo.full}</span>
                 </UiTooltipContent>
               </UiTooltip>
@@ -481,9 +481,9 @@ const chartDomain = React.useMemo(() => {
                 }
 
                 return (
-                  <div className="recharts-default-tooltip" style={{ margin: 0, padding: 10, backgroundColor: 'rgb(255, 255, 255)', border: '1px solid rgb(204, 204, 204)', whiteSpace: 'nowrap' }}>
-                    <p className="recharts-tooltip-label" style={{ margin: 0 }}>{t('time')}: {timeLabel}</p>
-                    <ul className="recharts-tooltip-item-list" style={{ padding: 0, margin: 0 }}>
+                  <div className="bg-background border border-border rounded shadow-lg" style={{ margin: 0, padding: 10, whiteSpace: 'nowrap' }}>
+                    <p className="text-foreground font-medium" style={{ margin: 0 }}>{t('time')}: {timeLabel}</p>
+                    <ul style={{ padding: 0, margin: 0 }}>
                       {payload.map((entry: any, index: number) => {
                         const labelInfo = seriesLabels[entry.dataKey] || { display: entry.name, full: entry.name };
                         const isTemplate = entry.dataKey?.toString().includes('template');
@@ -493,12 +493,12 @@ const chartDomain = React.useMemo(() => {
                         return (
                           <li
                             key={`item-${index}`}
-                            className="recharts-tooltip-item"
+                            className="text-foreground"
                             style={{ display: 'block', paddingTop: 4, paddingBottom: 4, color: entry.color, opacity }}
                           >
-                            <span className="recharts-tooltip-item-name" title={labelInfo.full}>{labelInfo.display}</span>
-                            <span className="recharts-tooltip-item-separator">: </span>
-                            <span className="recharts-tooltip-item-value">{value} {t('unitNgml')}</span>
+                            <span title={labelInfo.full}>{labelInfo.display}</span>
+                            <span>: </span>
+                            <span>{value} {t('unitNgml')}</span>
                           </li>
                         );
                       })}