/* ================================
   DESIGN SYSTEM - HOSTEL EXPENSE MANAGER
   Fresh Green Theme with Soft Rounded Design
   ================================ */

:root {
  /* Color System - HSL Format */
  --primary: 145 55% 38%;           /* Emerald green - brand color */
  --primary-hover: 145 60% 30%;     /* Darker emerald for hover */
  --primary-light: 150 55% 70%;     /* Mint - accent */
  --primary-glow: 145 50% 48%;      /* Brighter green for effects */
  
  --accent: 150 55% 70%;            /* Mint accent */
  --accent-light: 150 50% 96%;      /* Soft mint tint */
  
  --sage: 135 20% 72%;              /* Sage - neutral green */
  --sage-light: 135 20% 90%;        /* Light sage for borders */
  
  --background: 210 20% 98%;        /* Off-white */
  --surface: 0 0% 100%;             /* Pure white for cards */
  --border: 210 15% 90%;            /* Subtle borders */
  
  --foreground: 210 10% 25%;        /* Body text - dark gray */
  --foreground-muted: 210 8% 45%;   /* Muted text */
  --foreground-light: 210 8% 65%;   /* Light text */
  
  --success: 145 55% 38%;           /* Green for positive */
  --warning: 45 95% 55%;            /* Amber for warnings */
  --danger: 0 72% 55%;              /* Red for negative */
  
  --shadow-sm: 0 2px 4px hsl(210 10% 25% / 0.06);
  --shadow-md: 0 4px 12px hsl(210 10% 25% / 0.08);
  --shadow-lg: 0 8px 24px hsl(210 10% 25% / 0.12);
  --shadow-glow: 0 0 24px hsl(var(--primary-glow) / 0.15);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-full: 9999px;
  
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
}

/* ================================
   GLOBAL RESET & BASE
   ================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background-image: url("./Login_bg.png");
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* ================================
   TYPOGRAPHY
   ================================ */

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  color: hsl(var(--foreground));
}

h1 {
  font-size: 2rem;
  font-weight: 700;
}

h2 {
  font-size: 1.5rem;
}

h3 {
  font-size: 1.25rem;
}

h4 {
  font-size: 1.125rem;
}

p {
  line-height: 1.6;
  color: hsl(var(--foreground-muted));
}

.text-muted {
  color: hsl(var(--foreground-muted));
  font-size: 0.875rem;
}

.text-light {
  color: hsl(var(--foreground-light));
  font-size: 0.875rem;
}

/* ================================
   LAYOUT - LOGIN PAGE
   ================================ */

.login-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background-size: cover;
  background-position: center;
  padding: var(--spacing-lg);
  position: relative;
}

.login-container::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(2px);
}

.login-card {
  position: relative;
  z-index: 1;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  border-radius: var(--radius-xl);
  padding: var(--spacing-2xl);
  width: 100%;
  max-width: 420px;
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.login-logo {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  margin: 0 auto var(--spacing-lg);
}

.login-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.login-header h1 {
  margin-bottom: var(--spacing-sm);
  color: hsl(var(--foreground));
}

.login-header p {
  color: hsl(var(--foreground-muted));
  font-size: 0.95rem;
}

/* ================================
   LAYOUT - MAIN APP
   ================================ */

.app-container {
  display: flex;
  min-height: 100vh;
  background: hsl(var(--background));
}

.sidebar {
  width: 260px;
  background: hsl(var(--surface));
  border-right: 1px solid hsl(var(--border));
  padding: var(--spacing-lg);
  display: flex;
  flex-direction: column;
  position: fixed;
  height: 100vh;
  left: 0;
  top: 0;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-2xl);
  padding-bottom: var(--spacing-lg);
  border-bottom: 1px solid hsl(var(--border));
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.logo-text h3 {
  font-size: 1.125rem;
  color: hsl(var(--foreground));
  margin-bottom: 2px;
}

.logo-text p {
  font-size: 0.75rem;
  color: hsl(var(--foreground-muted));
}

.nav-menu {
  list-style: none;
  flex: 1;
}

.nav-item {
  margin-bottom: var(--spacing-sm);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: hsl(var(--foreground-muted));
  font-weight: 500;
  transition: all var(--transition);
  cursor: pointer;
}

.nav-link:hover {
  background: hsl(var(--accent-light));
  color: hsl(var(--primary));
}

.nav-link.active {
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  color: white;
  box-shadow: var(--shadow-glow);
}

.nav-icon {
  font-size: 1.25rem;
  width: 24px;
  text-align: center;
}

.main-content {
  flex: 1;
  margin-left: 260px;
  padding: var(--spacing-xl);
  min-height: 100vh;
}

.page-header {
  margin-bottom: var(--spacing-xl);
}

.page-header h1 {
  margin-bottom: var(--spacing-sm);
}

.page-header p {
  font-size: 1rem;
}

/* ================================
   CARDS & CONTAINERS
   ================================ */

.card {
  background: hsl(var(--surface));
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid hsl(var(--border));
  transition: all var(--transition);
  margin-bottom: 24px;
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid hsl(var(--border));
}

.card-header h3 {
  font-size: 1.125rem;
  color: hsl(var(--foreground));
}

.card-body {
  padding: 0;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

/* ================================
   STAT CARDS
   ================================ */

.stat-card {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.stat-card .stat-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
}

.stat-card.primary .stat-icon {
  background: linear-gradient(135deg, hsl(var(--primary) / 0.1), hsl(var(--primary-glow) / 0.1));
  color: hsl(var(--primary));
}

.stat-card.success .stat-icon {
  background: hsl(var(--success) / 0.1);
  color: hsl(var(--success));
}

.stat-card.warning .stat-icon {
  background: hsl(var(--warning) / 0.1);
  color: hsl(var(--warning));
}

.stat-card.danger .stat-icon {
  background: hsl(var(--danger) / 0.1);
  color: hsl(var(--danger));
}

.stat-label {
  font-size: 0.875rem;
  color: hsl(var(--foreground-muted));
  font-weight: 500;
}

.stat-value {
  font-size: 1.875rem;
  font-weight: 700;
  color: hsl(var(--foreground));
}

.stat-change {
  font-size: 0.875rem;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.stat-change.positive {
  color: hsl(var(--success));
}

.stat-change.negative {
  color: hsl(var(--danger));
}

/* ================================
   FORMS & INPUTS
   ================================ */

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
  color: hsl(var(--foreground));
  font-size: 0.875rem;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid hsl(var(--border));
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-family: inherit;
  background: hsl(var(--surface));
  color: hsl(var(--foreground));
  transition: all var(--transition);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: hsl(var(--primary));
  box-shadow: 0 0 0 3px hsl(var(--primary) / 0.1);
}

.form-textarea {
  resize: vertical;
  min-height: 100px;
}

::placeholder {
  color: hsl(var(--foreground-light));
}

/* ================================
   BUTTONS
   ================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: 12px 24px;
  border: none;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow), var(--shadow-md);
}

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

.btn-secondary {
  background: hsl(var(--surface));
  color: hsl(var(--foreground));
  border: 1.5px solid hsl(var(--border));
}

.btn-secondary:hover {
  border-color: hsl(var(--primary));
  color: hsl(var(--primary));
  background: hsl(var(--accent-light));
}

.btn-ghost {
  background: transparent;
  color: hsl(var(--foreground-muted));
  padding: 8px 16px;
}

.btn-ghost:hover {
  background: hsl(var(--accent-light));
  color: hsl(var(--primary));
}

.btn-danger {
  background: hsl(var(--danger));
  color: white;
}

.btn-danger:hover {
  background: hsl(0 72% 48%);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 0.875rem;
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: var(--radius-md);
}

/* ================================
   PROGRESS BAR
   ================================ */

.progress-bar {
  width: 100%;
  height: 12px;
  background: hsl(var(--sage-light));
  border-radius: var(--radius-full);
  overflow: hidden;
  margin: var(--spacing-md) 0;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

.progress-fill.warning {
  background: linear-gradient(90deg, hsl(var(--warning)), hsl(45 95% 65%));
}

.progress-fill.danger {
  background: linear-gradient(90deg, hsl(var(--danger)), hsl(0 72% 65%));
}

/* ================================
   CATEGORY BARS
   ================================ */

.category-bars {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.category-bar-item {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.category-bar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.category-bar-label {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-weight: 500;
  color: hsl(var(--foreground));
}

.category-bar-icon {
  font-size: 1.25rem;
}

.category-bar-amount {
  font-weight: 600;
  color: hsl(var(--foreground));
}

.category-bar {
  height: 8px;
  background: hsl(var(--sage-light));
  border-radius: var(--radius-full);
  overflow: hidden;
}

.category-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

/* ================================
   FILTERS & PILLS
   ================================ */

.filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xl);
}

.filter-pill {
  padding: 8px 16px;
  border-radius: var(--radius-full);
  background: hsl(var(--surface));
  border: 1.5px solid hsl(var(--border));
  color: hsl(var(--foreground-muted));
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.filter-pill:hover {
  border-color: hsl(var(--primary));
  color: hsl(var(--primary));
  background: hsl(var(--accent-light));
}

.filter-pill.active {
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  color: white;
  border-color: transparent;
}

/* ================================
   EXPENSE CARDS
   ================================ */

.expense-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.expense-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-lg);
  background: hsl(var(--surface));
  border: 1px solid hsl(var(--border));
  border-radius: var(--radius-lg);
  transition: all var(--transition);
  cursor: pointer;
}

.expense-card:hover {
  border-color: hsl(var(--primary));
  box-shadow: var(--shadow-md);
}

.expense-card-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex: 1;
}

.expense-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  background: hsl(var(--accent-light));
  color: hsl(var(--primary));
  flex-shrink: 0;
}

.expense-details {
  flex: 1;
  min-width: 0;
}

.expense-title {
  font-weight: 600;
  color: hsl(var(--foreground));
  margin-bottom: 4px;
}

.expense-meta {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.expense-date,
.expense-payer {
  font-size: 0.875rem;
  color: hsl(var(--foreground-muted));
  display: flex;
  align-items: center;
  gap: 4px;
}

.expense-tags {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: 4px;
}

.tag {
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 500;
}

.tag-category {
  background: hsl(var(--primary) / 0.1);
  color: hsl(var(--primary));
}

.tag-shared {
  background: hsl(var(--warning) / 0.1);
  color: hsl(var(--warning));
}

.tag-personal {
  background: hsl(210 10% 85%);
  color: hsl(var(--foreground-muted));
}

.expense-amount {
  text-align: right;
  flex-shrink: 0;
}

.expense-total {
  font-size: 1.125rem;
  font-weight: 700;
  color: hsl(var(--foreground));
  margin-bottom: 4px;
}

.expense-share {
  font-size: 0.875rem;
  color: hsl(var(--foreground-muted));
}

/* ================================
   ROOMMATE CARDS
   ================================ */

.roommate-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

.roommate-card {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-lg);
  background: hsl(var(--surface));
  border: 1px solid hsl(var(--border));
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.roommate-card:hover {
  border-color: hsl(var(--primary));
  box-shadow: var(--shadow-md);
}

.roommate-avatar {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: white;
  flex-shrink: 0;
}

.roommate-info {
  flex: 1;
  min-width: 0;
}

.roommate-name {
  font-weight: 600;
  color: hsl(var(--foreground));
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.badge-you {
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, hsl(var(--primary)), hsl(var(--primary-glow)));
  color: white;
  font-size: 0.7rem;
  font-weight: 600;
}

.roommate-actions {
  display: flex;
  gap: var(--spacing-sm);
}

/* ================================
   SETTLEMENT CARDS
   ================================ */

.settlement-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.settlement-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-lg);
  background: hsl(var(--surface));
  border: 1px solid hsl(var(--border));
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.settlement-card:hover {
  box-shadow: var(--shadow-md);
}

.settlement-card.owe {
  border-left: 4px solid hsl(var(--danger));
}

.settlement-card.owed {
  border-left: 4px solid hsl(var(--success));
}

.settlement-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex: 1;
}

.settlement-avatar {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 700;
  color: white;
  flex-shrink: 0;
}

.settlement-details {
  flex: 1;
}

.settlement-text {
  font-weight: 600;
  color: hsl(var(--foreground));
  margin-bottom: 4px;
}

.settlement-date {
  font-size: 0.875rem;
  color: hsl(var(--foreground-muted));
}

.settlement-amount {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 var(--spacing-lg);
}

.settlement-amount.owe {
  color: hsl(var(--danger));
}

.settlement-amount.owed {
  color: hsl(var(--success));
}

.settlement-actions {
  display: flex;
  gap: var(--spacing-sm);
}

/* ================================
   EMPTY STATES
   ================================ */

.empty-state {
  text-align: center;
  padding: var(--spacing-2xl);
}

.empty-icon {
  font-size: 4rem;
  margin-bottom: var(--spacing-lg);
  opacity: 0.5;
}

.empty-state h3 {
  margin-bottom: var(--spacing-sm);
  color: hsl(var(--foreground));
}

.empty-state p {
  margin-bottom: var(--spacing-xl);
  color: hsl(var(--foreground-muted));
}

/* ================================
   MODAL/DIALOG
   ================================ */

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: var(--spacing-lg);
}

.modal {
  background: hsl(var(--surface));
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-xl);
}

.modal-header h2 {
  color: hsl(var(--foreground));
}

.modal-close {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  border: none;
  background: transparent;
  color: hsl(var(--foreground-muted));
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  transition: all var(--transition);
}

.modal-close:hover {
  background: hsl(var(--accent-light));
  color: hsl(var(--primary));
}

.modal-footer {
  display: flex;
  gap: var(--spacing-md);
  justify-content: flex-end;
  margin-top: var(--spacing-xl);
}

/* ================================
   UTILITIES
   ================================ */

.hidden {
  display: none !important;
}

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.items-center {
  align-items: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-sm {
  gap: var(--spacing-sm);
}

.gap-md {
  gap: var(--spacing-md);
}

.gap-lg {
  gap: var(--spacing-lg);
}

.mt-auto {
  margin-top: auto;
}

.text-center {
  text-align: center;
}

/* ================================
   RESPONSIVE
   ================================ */

@media (max-width: 1024px) {
  body {
    font-size: 14px;
  }
  
  .sidebar {
    width: 220px;
  }
  
  .main-content {
    margin-left: 220px;
    padding: var(--spacing-lg);
  }
  
  .card-grid {
    grid-template-columns: 1fr 1fr;
  }
}