/* ========================================
   Design System - CSS Variables
   ======================================== */

:root {
  /* Brand Colors */
  --porto-blue: #004A97;
  --porto-blue-hover: #003a75;
  --m3-surface: #f8fafd;
  --m3-on-surface: #1b1b1f;
  --m3-surface-container: #eff1f8;
  --m3-surface-container-hover: #e3eaf5;
  --m3-active-item: #d3e3fd;
  --m3-border: rgba(38, 60, 103, 0.12);

  /* Text Colors */
  --text-primary: #1b1b1f;
  --text-secondary: #5f6368;
  --text-tertiary: #7c8288;

  /* Palette */
  --color-primary-400: #4f70c8;
  --color-primary-500: #004A97;
  --color-primary-600: #003a75;
  --color-success-500: #22c55e;
  --color-warning-500: #f59e0b;
  --color-error-500: #ef4444;

  /* Typography */
  --font-sans: 'Google Sans', 'Roboto', 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: 1.875rem;
  --font-size-4xl: 2.25rem;

  /* Spacing */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(27, 27, 31, 0.08);
  --shadow-md: 0 4px 10px rgba(27, 27, 31, 0.08);
  --shadow-lg: 0 10px 20px rgba(27, 27, 31, 0.08);
  --shadow-xl: 0 20px 30px rgba(27, 27, 31, 0.12);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 200ms ease-in-out;
  --transition-slow: 300ms ease-in-out;

  /* Z-index */
  --z-base: 1;
  --z-dropdown: 10;
  --z-sticky: 20;
  --z-modal: 30;
  --z-toast: 40;
  --z-loading: 50;
}

/* ========================================
   Reset & Base Styles
   ======================================== */

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

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

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--m3-surface);
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(circle at 20% 30%, rgba(0, 74, 151, 0.08) 0%, transparent 35%),
    radial-gradient(circle at 80% 80%, rgba(0, 74, 151, 0.04) 0%, transparent 35%);
  pointer-events: none;
  z-index: 0;
}

#app {
  position: relative;
  z-index: var(--z-base);
  min-height: 100vh;
}

/* ========================================
   Typography
   ======================================== */

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  color: var(--text-primary);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

p {
  margin-bottom: var(--spacing-4);
  color: var(--text-secondary);
}

a {
  color: var(--color-primary-400);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-300);
}

/* ========================================
   Utility Classes
   ======================================== */

.hidden {
  display: none !important;
}

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

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }

.text-success { color: var(--color-success-500); }
.text-warning { color: var(--color-warning-500); }
.text-error { color: var(--color-error-500); }

.mb-2 { margin-bottom: var(--spacing-2); }
.mb-4 { margin-bottom: var(--spacing-4); }
.mb-6 { margin-bottom: var(--spacing-6); }
.mb-8 { margin-bottom: var(--spacing-8); }

.mt-2 { margin-top: var(--spacing-2); }
.mt-4 { margin-top: var(--spacing-4); }
.mt-6 { margin-top: var(--spacing-6); }
.mt-8 { margin-top: var(--spacing-8); }

/* ========================================
   Loading Overlay
   ======================================== */

.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(10, 10, 15, 0.9);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-loading);
  opacity: 1;
  transition: opacity var(--transition-base);
}

.loading-overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border-color);
  border-top-color: var(--color-primary-500);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ========================================
   Toast Notifications
   ======================================== */

.toast-container {
  position: fixed;
  top: var(--spacing-4);
  right: var(--spacing-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
  max-width: 400px;
}

.toast {
  padding: var(--spacing-4);
  background: var(--bg-glass);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  animation: slideIn 0.3s ease-out;
}

.toast.success { border-left: 4px solid var(--color-success-500); }
.toast.error { border-left: 4px solid var(--color-error-500); }
.toast.warning { border-left: 4px solid var(--color-warning-500); }
.toast.info { border-left: 4px solid var(--color-primary-500); }

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

/* ========================================
   Animations
   ======================================== */

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

@keyframes scaleIn {
  from {
    transform: scale(0.95);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

.fade-in { animation: fadeIn 0.3s ease-out; }
.slide-up { animation: slideUp 0.4s ease-out; }
.scale-in { animation: scaleIn 0.3s ease-out; }

/* ========================================
   Responsive Design
   ======================================== */

@media (max-width: 768px) {
  html {
    font-size: 14px;
  }

  .toast-container {
    left: var(--spacing-4);
    right: var(--spacing-4);
    max-width: none;
  }
}