/* ===== CSS Custom Properties (Color Palette) ===== */
:root {
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --primary-light: #3b82f6;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --neutral-50: #ffffff;
  --neutral-100: #f3f4f6;
  --neutral-200: #e5e7eb;
  --neutral-700: #374151;
  --neutral-900: #111827;
}

/* ===== Global Styles ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--neutral-900);
  color: var(--neutral-50);
  line-height: 1.6;
  font-size: 16px;
}

/* ===== Container & Layout ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

header {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
  padding: 40px 20px;
  border-radius: 12px;
  margin-bottom: 40px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.header-text h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--neutral-50);
}

.header-text p {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.9);
  opacity: 0.95;
}

/* ===== Main Content ===== */
.main-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
  margin-bottom: 40px;
}

@media (max-width: 768px) {
  .main-content {
    grid-template-columns: 1fr;
  }
}

/* ===== Upload Section ===== */
.upload-section,
.manual-entry {
  background-color: var(--neutral-900);
  border: 2px solid var(--neutral-700);
  border-radius: 12px;
  padding: 30px;
  transition: all 0.3s ease;
}

.upload-section:hover,
.manual-entry:hover {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.upload-section h2,
.manual-entry h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--primary-light);
}

.upload-area {
  border: 2px dashed var(--primary);
  border-radius: 8px;
  padding: 40px 20px;
  text-align: center;
  background-color: rgba(37, 99, 235, 0.05);
  transition: all 0.3s ease;
  cursor: pointer;
}

.upload-area:hover {
  background-color: rgba(37, 99, 235, 0.1);
  border-color: var(--primary-light);
}

.upload-icon {
  font-size: 48px;
  margin-bottom: 16px;
}

.upload-area p {
  margin: 12px 0;
  color: var(--neutral-50);
}

.upload-area .drag-over{
  background-color: rgba(37, 99, 235, 0.1);
  border-color: var(--primary-light);
}

.upload-area p strong, .fileNameDisplay {
  color: var(--primary-light);
  font-weight: 600;
}

#fileInput {
  display: none;
}

/* ===== Form Styles ===== */
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 20px;
}

@media (max-width: 600px) {
  .form-grid {
    grid-template-columns: 1fr;
  }
}

.form-group {
  display: flex;
  flex-direction: column;
}

.form-group label {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--neutral-200);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.form-group input,
.form-group select {
  padding: 12px 14px;
  border: 1px solid var(--neutral-700);
  border-radius: 6px;
  background-color: rgba(255, 255, 255, 0.05);
  color: var(--neutral-50);
  font-size: 14px;
  transition: all 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  background-color: rgba(255, 255, 255, 0.1);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group input::placeholder {
  color: var(--neutral-700);
}

/* ===== Button Styles ===== */
.btn {
  padding: 12px 24px;
  border: none;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn {
  background-color: var(--primary);
  color: var(--neutral-50);
}

.btn:hover {
  background-color: var(--primary-light);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
}

.btn:active {
  transform: translateY(0);
}

.btn-secondary {
  background-color: var(--neutral-700);
  color: var(--neutral-50);
}

.btn-secondary:hover {
  background-color: var(--neutral-700);
  opacity: 0.8;
}

#browseBtn {
  width: 100%;
  margin: 16px 0;
}

#addExpense,
#clear {
  width: 100%;
  margin-top: 8px;
}

#clear {
  background-color: var(--neutral-700);
}

#clear:hover {
  background-color: var(--danger);
  opacity: 0.9;
}

/* ===== Output Content ===== */
.output-content {
  display: block;
}

/* ===== Alert ==== */
.alert{
  padding: 12px 14px;
  margin-bottom: 20px;
  border-radius: 5px;
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: rgba(17, 24, 39, 0.6);
  -webkit-backdrop-filter: blur(20px) brightness(1.1);
  backdrop-filter: blur(20px) brightness(1.1);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 
    0 8px 32px 0 rgba(0, 0, 0, 0.5),
    inset 0 0 20px 0 rgba(255, 255, 255, 0.05);
  animation: fade-up 200ms ease-in-out; 
}

@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.danger {
  border-left: 1px solid var(--danger);
  color: var(--danger);
}

.success {
  border-left: 1px solid var(--success);
  color: var(--success);
}



/* ===== Insights Cards ===== */
.insights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 40px;
}

.insight-card {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(59, 130, 246, 0.05) 100%);
  border: 1px solid var(--primary);
  border-radius: 12px;
  padding: 24px;
  text-align: center;
  transition: all 0.3s ease;
}

.insight-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 16px rgba(37, 99, 235, 0.2);
  border-color: var(--primary-light);
}

.insight-card h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--neutral-200);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.insight-card .value {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary-light);
}

/* ===== Chart Container ===== */
.chart-container {
  background-color: var(--neutral-900);
  border: 1px solid var(--neutral-700);
  border-radius: 12px;
  padding: 30px;
  margin-bottom: 40px;
}

.chart-container h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--primary-light);
}

#categoryChart {
  min-height: 300px;
}

/* ===== Expenses List ===== */
.expenses-list {
  background-color: var(--neutral-900);
  border: 1px solid var(--neutral-700);
  border-radius: 12px;
  padding: 30px;
  margin-bottom: 2.5rem;
}

.expenses-list h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--primary-light);
}

/* ===== Expense Items ===== */
.expense-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--neutral-700);
  border-radius: 8px;
  padding: 16px;
  transition: all 0.3s ease;
  margin-bottom: 10px;
}

.expense-item:hover {
  background-color: rgba(255, 255, 255, 0.05);
  border-color: var(--primary);
}

.capitalize {
  text-transform: capitalize;
}


.expense-date {
  font-size: 18px;
  color: var(--neutral-700);
  margin-right: 10px;
}


.expense-category {
  text-transform: capitalize;
  font-size: 18px;
  color: var(--neutral-200);
  text-transform: capitalize;
  margin-right: 10px;
}

.expense-description {
  font-weight: 600;
  color: var(--neutral-50);
  margin-bottom: 4px;
  margin-right: 10px;
}


.expense-amount {  
  font-size: 18px;
  font-weight: 700;
  color: var(--success);
  margin-right: 10px;
}


/* ===== Scrollbar Styling ===== */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background-color: var(--neutral-900);
}

::-webkit-scrollbar-thumb {
  background-color: var(--primary);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background-color: var(--primary-light);
}

/* ===== Accessibility ===== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}