/* ===============================================
   Digital Health Tracker - Main Stylesheet
   Modern, responsive design with theme support
   =============================================== */

/* ===== CSS Variables & Theme System ===== */
:root {
  /* Color Palette - Light Theme */
  --primary-color: #14b8a6;
  --primary-dark: #0f766e;
  --primary-light: #5eead4;
  --secondary-color: #8b5cf6;
  --accent-color: #f97316;
  --success-color: #22c55e;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #14b8a6 0%, #3b82f6 50%, #8b5cf6 100%);
  --gradient-secondary: linear-gradient(135deg, #f97316 0%, #f59e0b 100%);
  --gradient-success: linear-gradient(135deg, #10b981 0%, #14b8a6 100%);
  
  /* Backgrounds */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --bg-overlay: rgba(255, 255, 255, 0.95);
  --bg-card: rgba(255, 255, 255, 0.8);
  
  /* Text Colors */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  --text-inverse: #ffffff;
  
  /* Borders & Shadows */
  --border-color: #e2e8f0;
  --border-radius: 12px;
  --border-radius-lg: 16px;
  --border-radius-xl: 24px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* Typography */
  --font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-overlay: rgba(15, 23, 42, 0.95);
  --bg-card: rgba(30, 41, 59, 0.8);
  
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-tertiary: #64748b;
  --text-inverse: #0f172a;
  
  --border-color: #334155;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background-color var(--transition-base), color var(--transition-base);
  overflow-x: hidden;
}

/* Animated Gradient Background */
.gradient-background {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  background: var(--gradient-primary);
  background-size: 200% 200%;
  animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

h1 { font-size: var(--font-size-3xl); }
h2 { font-size: var(--font-size-2xl); }
h3 { font-size: var(--font-size-xl); }
h4 { font-size: var(--font-size-lg); }
h5 { font-size: var(--font-size-base); }
h6 { font-size: var(--font-size-sm); }

p {
  margin-bottom: var(--spacing-md);
  color: var(--text-secondary);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-dark);
}

/* ===== Layout Components ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.page-wrapper {
  min-height: 100vh;
  padding: var(--spacing-xl) 0;
}

.content-section {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.content-section:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

/* ===== Navigation ===== */
.navbar {
  position: sticky;
  top: 0;
  background: var(--bg-overlay);
  backdrop-filter: blur(10px);
  padding: var(--spacing-md) 0;
  box-shadow: var(--shadow-md);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.nav-brand {
  font-size: var(--font-size-xl);
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
  color: var(--primary-color);
  background: var(--bg-tertiary);
}

/* ===== Cards ===== */
.card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: all var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.card-header {
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-md);
  border-bottom: 2px solid var(--border-color);
}

.card-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.card-subtitle {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
}

.card-body {
  margin-bottom: var(--spacing-md);
}

.card-footer {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  font-size: var(--font-size-base);
  font-weight: 600;
  text-align: center;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  outline: none;
}

.btn:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--text-inverse);
  box-shadow: var(--shadow-md);
}

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

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

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

.btn-outline {
  background: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-outline:hover {
  background: var(--primary-color);
  color: var(--text-inverse);
}

.btn-sm {
  padding: var(--spacing-xs) var(--spacing-md);
  font-size: var(--font-size-sm);
}

.btn-lg {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-lg);
}

/* Floating Action Button */
.fab {
  position: fixed;
  bottom: var(--spacing-xl);
  right: var(--spacing-xl);
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--gradient-primary);
  color: var(--text-inverse);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-2xl);
  border: none;
  cursor: pointer;
  box-shadow: var(--shadow-xl);
  z-index: 999;
  transition: all var(--transition-base);
  animation: float 3s ease-in-out infinite;
}

.fab:hover {
  transform: scale(1.1);
  box-shadow: 0 25px 35px -5px rgba(0, 0, 0, 0.2);
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ===== Forms ===== */
.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 600;
  color: var(--text-primary);
  font-size: var(--font-size-sm);
}

.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: var(--spacing-md);
  font-size: var(--font-size-base);
  font-family: var(--font-family);
  background: var(--bg-primary);
  color: var(--text-primary);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
  outline: none;
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(20, 184, 166, 0.1);
}

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

/* ===== Grid System ===== */
.grid {
  display: grid;
  gap: var(--spacing-lg);
}

.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 768px) {
  .grid-cols-2, .grid-cols-3, .grid-cols-4 {
    grid-template-columns: 1fr;
  }
}

/* ===== Stats/Metrics Display ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.stat-card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-primary);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.stat-icon {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--spacing-sm);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-value {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.stat-label {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Progress Bars */
.progress-bar {
  height: 8px;
  background: var(--bg-tertiary);
  border-radius: 999px;
  overflow: hidden;
  margin-top: var(--spacing-sm);
}

.progress-fill {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: 999px;
  transition: width var(--transition-slow);
}

/* ===== Charts Container ===== */
.chart-container {
  position: relative;
  height: 300px;
  margin-bottom: var(--spacing-xl);
  padding: var(--spacing-lg);
  background: var(--bg-card);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
}

/* ===== Mood Heatmap ===== */
.mood-heatmap {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.mood-day {
  aspect-ratio: 1;
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xl);
  cursor: pointer;
  transition: transform var(--transition-fast);
  background: var(--bg-tertiary);
}

.mood-day:hover {
  transform: scale(1.1);
}

/* ===== Toasts/Notifications ===== */
.toast-container {
  position: fixed;
  top: var(--spacing-xl);
  right: var(--spacing-xl);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.toast {
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--border-radius);
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  color: var(--text-primary);
  box-shadow: var(--shadow-xl);
  min-width: 300px;
  border-left: 4px solid var(--primary-color);
  animation: slideIn var(--transition-base);
}

.toast.success { border-left-color: var(--success-color); }
.toast.warning { border-left-color: var(--warning-color); }
.toast.error { border-left-color: var(--danger-color); }

@keyframes slideIn {
  from {
    transform: translateX(400px);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

/* ===== Modal ===== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.modal {
  background: var(--bg-primary);
  border-radius: var(--border-radius-xl);
  padding: var(--spacing-2xl);
  max-width: 600px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  transform: scale(0.9);
  transition: transform var(--transition-base);
}

.modal-overlay.active .modal {
  transform: scale(1);
}

/* ===== Health Score Display ===== */
.health-score {
  text-align: center;
  padding: var(--spacing-2xl);
  background: var(--bg-card);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--spacing-xl);
}

.score-circle {
  width: 200px;
  height: 200px;
  margin: 0 auto var(--spacing-lg);
  border-radius: 50%;
  background: conic-gradient(
    var(--primary-color) 0deg,
    var(--primary-color) calc(var(--score) * 3.6deg),
    var(--bg-tertiary) calc(var(--score) * 3.6deg),
    var(--bg-tertiary) 360deg
  );
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.score-circle::before {
  content: '';
  position: absolute;
  width: 170px;
  height: 170px;
  background: var(--bg-card);
  border-radius: 50%;
}

.score-value {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  position: relative;
  z-index: 1;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== Flags/Alerts (Doctor View) ===== */
.flag {
  padding: var(--spacing-md);
  border-radius: var(--border-radius);
  border-left: 4px solid;
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: start;
  gap: var(--spacing-md);
}

.flag.warning {
  background: rgba(245, 158, 11, 0.1);
  border-left-color: var(--warning-color);
}

.flag.danger {
  background: rgba(239, 68, 68, 0.1);
  border-left-color: var(--danger-color);
}

.flag-icon {
  font-size: var(--font-size-xl);
  flex-shrink: 0;
}

/* ===== Onboarding Stepper ===== */
.stepper {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--spacing-2xl);
  position: relative;
}

.stepper::before {
  content: '';
  position: absolute;
  top: 20px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--border-color);
  z-index: -1;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  flex: 1;
}

.step-circle {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-tertiary);
  border: 2px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  transition: all var(--transition-base);
}

.step.active .step-circle {
  background: var(--primary-color);
  color: var(--text-inverse);
  border-color: var(--primary-color);
}

.step.completed .step-circle {
  background: var(--success-color);
  color: var(--text-inverse);
  border-color: var(--success-color);
}

.step-label {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  text-align: center;
}

/* ===== Utility Classes ===== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: var(--spacing-md); }
.mt-2 { margin-top: var(--spacing-lg); }
.mt-3 { margin-top: var(--spacing-xl); }

.mb-1 { margin-bottom: var(--spacing-md); }
.mb-2 { margin-bottom: var(--spacing-lg); }
.mb-3 { margin-bottom: var(--spacing-xl); }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: var(--spacing-md); }
.gap-2 { gap: var(--spacing-lg); }

.hidden { display: none !important; }

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
  .container {
    max-width: 100%;
  }
  
  .stats-grid {
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  }
}

@media (max-width: 768px) {
  :root {
    font-size: 14px;
  }
  
  .nav-links {
    gap: var(--spacing-sm);
  }
  
  .nav-link {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-sm);
  }
}
  .score-circle {
    width: 150px;
    height: 150px;
  }
  
  .score-circle::before {
    width: 120px;
    height: 120px;
  }
}

@media (max-width: 480px) {
  .page-wrapper {
    padding: var(--spacing-md) 0;
  }
  
  .content-section {
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
  }
  
  .mood-heatmap {
    grid-template-columns: repeat(7, 1fr);
    gap: var(--spacing-xs);
  }
}

/* ===== Accessibility ===== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

*:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --border-color: currentColor;
  }
  
  .btn {
    border: 2px solid currentColor;
  }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Print styles */
@media print {
  .navbar, .fab, .toast-container {
    display: none !important;
  }
  
  .page-wrapper {
    padding: 0;
  }
  
  .card, .content-section {
    break-inside: avoid;
  }
}