diff --git a/frontend/src/pages/Categories.jsx b/frontend/src/pages/Categories.jsx
index 966d329..214b4b9 100644
--- a/frontend/src/pages/Categories.jsx
+++ b/frontend/src/pages/Categories.jsx
@@ -250,8 +250,8 @@ const Categories = () => {
   const renderCategory = (category, level = 0, parentColor = null) => {
     const hasChildren = category.children && category.children.length > 0;
     const isExpanded = expandedCategories[category.id];
-    // Subcategorias herdam a cor da categoria pai
-    const displayColor = level > 0 && parentColor ? parentColor : category.color;
+    // Subcategorias herdam a cor da categoria pai - garantir que sempre use a cor do pai se disponível
+    const displayColor = level > 0 && parentColor ? parentColor : (category.color || '#94a3b8');
 
     return (
       <div key={category.id}>
@@ -343,7 +343,7 @@ const Categories = () => {
         {/* Children */}
         {hasChildren && isExpanded && (
           <div>
-            {category.children.map(child => renderCategory(child, level + 1, category.color))}
+            {category.children.map(child => renderCategory(child, level + 1, displayColor))}
           </div>
         )}
       </div>
diff --git a/frontend/src/pages/Reports.jsx b/frontend/src/pages/Reports.jsx
index 82df9b7..c2570d0 100644
--- a/frontend/src/pages/Reports.jsx
+++ b/frontend/src/pages/Reports.jsx
@@ -35,6 +35,15 @@ const Reports = () => {
   const { t } = useTranslation();
   const { currency, date: formatDate } = useFormatters();
   
+  // Mobile detection
+  const [isMobile, setIsMobile] = useState(window.innerWidth < 768);
+
+  useEffect(() => {
+    const handleResize = () => setIsMobile(window.innerWidth < 768);
+    window.addEventListener('resize', handleResize);
+    return () => window.removeEventListener('resize', handleResize);
+  }, []);
+  
   const [activeTab, setActiveTab] = useState('summary');
   const [loading, setLoading] = useState(true);
   const [year, setYear] = useState(new Date().getFullYear());
@@ -178,11 +187,11 @@ const Reports = () => {
     const monthlyAvgBalance = (summary.current.balance / 12).toFixed(2);
 
     return (
-      <div className="row g-4">
+      <div className="row g-3">
         {/* Year Selector */}
         <div className="col-12">
           <div className="d-flex align-items-center justify-content-between mb-3">
-            <h5 className="text-white mb-0">
+            <h5 className="text-white mb-0" style={{ fontSize: isMobile ? '0.95rem' : '1.25rem' }}>
               <i className="bi bi-calendar3 me-2"></i>
               {t('reports.annualSummary')}
             </h5>
@@ -190,8 +199,12 @@ const Reports = () => {
               {[2024, 2025].map(y => (
                 <button
                   key={y}
-                  className={`btn btn-sm ${year === y ? 'btn-primary' : 'btn-outline-secondary'}`}
+                  className={`btn ${year === y ? 'btn-primary' : 'btn-outline-secondary'}`}
                   onClick={() => setYear(y)}
+                  style={{ 
+                    fontSize: isMobile ? '0.75rem' : '0.875rem',
+                    padding: isMobile ? '0.25rem 0.75rem' : '0.375rem 1rem'
+                  }}
                 >
                   {y}
                 </button>
@@ -201,29 +214,38 @@ const Reports = () => {
         </div>
 
         {/* Main KPI Cards */}
-        <div className="col-lg-3 col-md-6">
+        <div className={isMobile ? "col-12" : "col-lg-3 col-md-6"}>
           <div className="card border-0 h-100" style={{ background: 'linear-gradient(135deg, #059669 0%, #047857 100%)' }}>
-            <div className="card-body text-white">
-              <div className="d-flex align-items-center justify-content-between mb-3">
-                <div>
-                  <div className="opacity-75 small text-uppercase fw-semibold mb-1">{t('reports.income')}</div>
-                  <h3 className="mb-0 fw-bold">{currency(summary.current.income, summary.currency)}</h3>
-                </div>
-                <div className="fs-1 opacity-50">
-                  <i className="bi bi-arrow-up-circle"></i>
+            <div className="card-body text-white" style={{ padding: isMobile ? '0.75rem' : '1rem' }}>
+              <div className="d-flex align-items-center justify-content-between mb-2">
+                <div style={{ minWidth: 0, flex: 1 }}>
+                  <div className="opacity-75 text-uppercase fw-semibold mb-1" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.income')}
+                  </div>
+                  <h3 className="mb-0 fw-bold" style={{ fontSize: isMobile ? '1.1rem' : '1.5rem' }}>
+                    {currency(summary.current.income, summary.currency)}
+                  </h3>
                 </div>
+                {!isMobile && (
+                  <div className="fs-1 opacity-50">
+                    <i className="bi bi-arrow-up-circle"></i>
+                  </div>
+                )}
               </div>
               {summary.variation.income !== 0 && !isNaN(summary.variation.income) && isFinite(summary.variation.income) && (
                 <div className="d-flex align-items-center gap-2">
-                  <span className={`badge ${summary.variation.income >= 0 ? 'bg-white text-success' : 'bg-white text-danger'} px-2 py-1`}>
+                  <span className={`badge ${summary.variation.income >= 0 ? 'bg-white text-success' : 'bg-white text-danger'}`}
+                        style={{ fontSize: isMobile ? '0.65rem' : '0.75rem', padding: isMobile ? '0.25rem 0.5rem' : '0.375rem 0.75rem' }}>
                     <i className={`bi bi-arrow-${summary.variation.income >= 0 ? 'up' : 'down'} me-1`}></i>
                     {Math.abs(summary.variation.income).toFixed(1)}%
                   </span>
-                  <small className="opacity-75">{t('reports.vsLastYear')}</small>
+                  <small className="opacity-75" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.vsLastYear')}
+                  </small>
                 </div>
               )}
               <hr className="my-2 opacity-25" />
-              <div className="small d-flex justify-content-between">
+              <div className="d-flex justify-content-between" style={{ fontSize: isMobile ? '0.7rem' : '0.875rem' }}>
                 <span className="opacity-75">{t('reports.monthlyAverage')}:</span>
                 <span className="fw-semibold">{currency(monthlyAvgIncome, summary.currency)}</span>
               </div>
@@ -231,29 +253,38 @@ const Reports = () => {
           </div>
         </div>
 
-        <div className="col-lg-3 col-md-6">
+        <div className={isMobile ? "col-12" : "col-lg-3 col-md-6"}>
           <div className="card border-0 h-100" style={{ background: 'linear-gradient(135deg, #dc2626 0%, #b91c1c 100%)' }}>
-            <div className="card-body text-white">
-              <div className="d-flex align-items-center justify-content-between mb-3">
-                <div>
-                  <div className="opacity-75 small text-uppercase fw-semibold mb-1">{t('reports.expenses')}</div>
-                  <h3 className="mb-0 fw-bold">{currency(summary.current.expense, summary.currency)}</h3>
-                </div>
-                <div className="fs-1 opacity-50">
-                  <i className="bi bi-arrow-down-circle"></i>
+            <div className="card-body text-white" style={{ padding: isMobile ? '0.75rem' : '1rem' }}>
+              <div className="d-flex align-items-center justify-content-between mb-2">
+                <div style={{ minWidth: 0, flex: 1 }}>
+                  <div className="opacity-75 text-uppercase fw-semibold mb-1" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.expenses')}
+                  </div>
+                  <h3 className="mb-0 fw-bold" style={{ fontSize: isMobile ? '1.1rem' : '1.5rem' }}>
+                    {currency(summary.current.expense, summary.currency)}
+                  </h3>
                 </div>
+                {!isMobile && (
+                  <div className="fs-1 opacity-50">
+                    <i className="bi bi-arrow-down-circle"></i>
+                  </div>
+                )}
               </div>
               {summary.variation.expense !== 0 && !isNaN(summary.variation.expense) && isFinite(summary.variation.expense) && (
                 <div className="d-flex align-items-center gap-2">
-                  <span className={`badge ${summary.variation.expense <= 0 ? 'bg-white text-success' : 'bg-white text-danger'} px-2 py-1`}>
+                  <span className={`badge ${summary.variation.expense <= 0 ? 'bg-white text-success' : 'bg-white text-danger'}`}
+                        style={{ fontSize: isMobile ? '0.65rem' : '0.75rem', padding: isMobile ? '0.25rem 0.5rem' : '0.375rem 0.75rem' }}>
                     <i className={`bi bi-arrow-${summary.variation.expense >= 0 ? 'up' : 'down'} me-1`}></i>
                     {Math.abs(summary.variation.expense).toFixed(1)}%
                   </span>
-                  <small className="opacity-75">{t('reports.vsLastYear')}</small>
+                  <small className="opacity-75" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.vsLastYear')}
+                  </small>
                 </div>
               )}
               <hr className="my-2 opacity-25" />
-              <div className="small d-flex justify-content-between">
+              <div className="d-flex justify-content-between" style={{ fontSize: isMobile ? '0.7rem' : '0.875rem' }}>
                 <span className="opacity-75">{t('reports.monthlyAverage')}:</span>
                 <span className="fw-semibold">{currency(monthlyAvgExpense, summary.currency)}</span>
               </div>
@@ -261,29 +292,38 @@ const Reports = () => {
           </div>
         </div>
 
-        <div className="col-lg-3 col-md-6">
+        <div className={isMobile ? "col-12" : "col-lg-3 col-md-6"}>
           <div className="card border-0 h-100" style={{ background: 'linear-gradient(135deg, #3b82f6 0%, #2563eb 100%)' }}>
-            <div className="card-body text-white">
-              <div className="d-flex align-items-center justify-content-between mb-3">
-                <div>
-                  <div className="opacity-75 small text-uppercase fw-semibold mb-1">{t('reports.balance')}</div>
-                  <h3 className="mb-0 fw-bold">{currency(summary.current.balance, summary.currency)}</h3>
-                </div>
-                <div className="fs-1 opacity-50">
-                  <i className="bi bi-wallet2"></i>
+            <div className="card-body text-white" style={{ padding: isMobile ? '0.75rem' : '1rem' }}>
+              <div className="d-flex align-items-center justify-content-between mb-2">
+                <div style={{ minWidth: 0, flex: 1 }}>
+                  <div className="opacity-75 text-uppercase fw-semibold mb-1" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.balance')}
+                  </div>
+                  <h3 className="mb-0 fw-bold" style={{ fontSize: isMobile ? '1.1rem' : '1.5rem' }}>
+                    {currency(summary.current.balance, summary.currency)}
+                  </h3>
                 </div>
+                {!isMobile && (
+                  <div className="fs-1 opacity-50">
+                    <i className="bi bi-wallet2"></i>
+                  </div>
+                )}
               </div>
               {summary.variation.balance !== 0 && !isNaN(summary.variation.balance) && isFinite(summary.variation.balance) && (
                 <div className="d-flex align-items-center gap-2">
-                  <span className={`badge ${summary.variation.balance >= 0 ? 'bg-white text-success' : 'bg-white text-danger'} px-2 py-1`}>
+                  <span className={`badge ${summary.variation.balance >= 0 ? 'bg-white text-success' : 'bg-white text-danger'}`}
+                        style={{ fontSize: isMobile ? '0.65rem' : '0.75rem', padding: isMobile ? '0.25rem 0.5rem' : '0.375rem 0.75rem' }}>
                     <i className={`bi bi-arrow-${summary.variation.balance >= 0 ? 'up' : 'down'} me-1`}></i>
                     {Math.abs(summary.variation.balance).toFixed(1)}%
                   </span>
-                  <small className="opacity-75">{t('reports.vsLastYear')}</small>
+                  <small className="opacity-75" style={{ fontSize: isMobile ? '0.65rem' : '0.75rem' }}>
+                    {t('reports.vsLastYear')}
+                  </small>
                 </div>
               )}
               <hr className="my-2 opacity-25" />
-              <div className="small d-flex justify-content-between">
+              <div className="d-flex justify-content-between" style={{ fontSize: isMobile ? '0.7rem' : '0.875rem' }}>
                 <span className="opacity-75">{t('reports.monthlyAverage')}:</span>
                 <span className="fw-semibold">{currency(monthlyAvgBalance, summary.currency)}</span>
               </div>
@@ -1761,28 +1801,34 @@ const Reports = () => {
   return (
     <div className="reports-container">
       {/* Header */}
-      <div className="d-flex justify-content-between align-items-center mb-4">
+      <div className={`d-flex ${isMobile ? 'flex-column gap-2' : 'justify-content-between align-items-center'} mb-4`}>
         <div>
-          <h4 className="text-white mb-1 fw-bold">
+          <h4 className="text-white mb-1 fw-bold" style={{ fontSize: isMobile ? '1.1rem' : '1.5rem' }}>
             <i className="bi bi-bar-chart-line me-2"></i>
             {t('reports.title')}
           </h4>
-          <p className="text-slate-400 mb-0 small">{t('reports.subtitle')}</p>
+          <p className="text-slate-400 mb-0" style={{ fontSize: isMobile ? '0.75rem' : '0.875rem' }}>
+            {t('reports.subtitle')}
+          </p>
         </div>
       </div>
 
       {/* Tabs */}
       <div className="card border-0 mb-4" style={{ background: '#0f172a' }}>
-        <div className="card-body p-2">
-          <div className="d-flex flex-wrap gap-2">
+        <div className="card-body" style={{ padding: isMobile ? '0.5rem' : '0.75rem' }}>
+          <div className="d-flex flex-wrap gap-1">
             {tabs.map(tab => (
               <button
                 key={tab.id}
-                className={`btn btn-sm ${activeTab === tab.id ? 'btn-primary' : 'btn-outline-secondary'}`}
+                className={`btn ${activeTab === tab.id ? 'btn-primary' : 'btn-outline-secondary'}`}
                 onClick={() => setActiveTab(tab.id)}
+                style={{ 
+                  fontSize: isMobile ? '0.7rem' : '0.875rem',
+                  padding: isMobile ? '0.25rem 0.5rem' : '0.375rem 0.75rem'
+                }}
               >
-                <i className={`bi ${tab.icon} me-1`}></i>
-                {tab.label}
+                <i className={`bi ${tab.icon} ${isMobile ? '' : 'me-1'}`}></i>
+                {isMobile ? '' : tab.label}
               </button>
             ))}
           </div>