/* ============================================
   Finance 101 - Main Stylesheet
   Design System Variables & Base Styles
   ============================================ */

/* CSS Custom Properties (Design Tokens) */
:root {
  /* Colors - Primary Palette */
  --color-primary: #22C55E;
  --color-primary-dark: #16A34A;
  --color-primary-light: #4ADE80;
  --color-primary-bg: #DCFCE7;

  /* Colors - Secondary (Trust Blue) */
  --color-secondary: #3B82F6;
  --color-secondary-dark: #2563EB;
  --color-secondary-light: #60A5FA;
  --color-secondary-bg: #DBEAFE;

  /* Colors - Accent (Gold) */
  --color-accent: #F59E0B;
  --color-accent-dark: #D97706;
  --color-accent-light: #FBBF24;
  --color-accent-bg: #FEF3C7;

  /* Colors - Semantic */
  --color-success: #22C55E;
  --color-warning: #F59E0B;
  --color-error: #EF4444;
  --color-info: #3B82F6;

  /* Colors - Neutrals */
  --color-text: #1E293B;
  --color-text-light: #64748B;
  --color-text-muted: #94A3B8;
  --color-background: #F8FAFC;
  --color-surface: #FFFFFF;
  --color-border: #E2E8F0;
  --color-border-light: #F1F5F9;

  /* Typography */
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', Consolas, monospace;

  /* Font Sizes */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  --text-7xl: 4.5rem;

  /* Font Weights */
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  --font-extrabold: 800;

  /* Line Heights */
  --leading-tight: 1.25;
  --leading-snug: 1.375;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;

  /* Spacing Scale */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
  --shadow-card: 0 4px 20px rgb(0 0 0 / 0.08);
  --shadow-card-hover: 0 8px 30px rgb(0 0 0 / 0.12);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;
  --transition-bounce: 500ms cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* Z-Index Scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-popover: 600;
  --z-tooltip: 700;

  /* Container Widths */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;
  --container-2xl: 1536px;
}

/* Global Dark Theme Variables */
html.theme-dark {
  color-scheme: dark;
  --color-primary: #4ade80;
  --color-primary-dark: #22c55e;
  --color-primary-light: #86efac;
  --color-primary-bg: #123225;

  --color-secondary: #60a5fa;
  --color-secondary-dark: #3b82f6;
  --color-secondary-light: #93c5fd;
  --color-secondary-bg: #162a47;

  --color-accent: #fbbf24;
  --color-accent-dark: #f59e0b;
  --color-accent-light: #fcd34d;
  --color-accent-bg: #3a2b12;

  --color-text: #e5edf6;
  --color-text-light: #9db0c7;
  --color-text-muted: #7f93ac;
  --color-background: #0b1220;
  --color-surface: #131d30;
  --color-border: #25334a;
  --color-border-light: #1b2a42;

  --shadow-card: 0 4px 20px rgb(2 7 18 / 0.28);
  --shadow-card-hover: 0 8px 30px rgb(2 7 18 / 0.42);
}

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

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--color-text);
}

h1 {
  font-size: var(--text-5xl);
  font-weight: var(--font-extrabold);
}

h2 {
  font-size: var(--text-4xl);
  font-weight: var(--font-bold);
}

h3 {
  font-size: var(--text-2xl);
  font-weight: var(--font-bold);
}

h4 {
  font-size: var(--text-xl);
  font-weight: var(--font-semibold);
}

h5 {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
}

h6 {
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
}

p {
  margin-bottom: var(--space-4);
}

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

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

strong, b {
  font-weight: var(--font-semibold);
}

small {
  font-size: var(--text-sm);
}

/* Lists */
ul, ol {
  padding-left: var(--space-6);
  margin-bottom: var(--space-4);
}

li {
  margin-bottom: var(--space-2);
}

/* Images */
img, picture, video, canvas, svg {
  display: block;
  max-width: 100%;
  height: auto;
}

/* Forms */
input, button, textarea, select {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  background: none;
  border: none;
}

/* Tables */
table {
  border-collapse: collapse;
  width: 100%;
}

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

/* Selection */
::selection {
  background-color: var(--color-primary-bg);
  color: var(--color-text);
}

/* ============================================
   Layout Utilities
   ============================================ */

.container {
  width: 100%;
  max-width: var(--container-xl);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

@media (min-width: 640px) {
  .container {
    padding-left: var(--space-6);
    padding-right: var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding-left: var(--space-8);
    padding-right: var(--space-8);
  }
}

.container-narrow {
  max-width: var(--container-md);
}

.container-wide {
  max-width: var(--container-2xl);
}

/* Flexbox Utilities */
.flex {
  display: flex;
}

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

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

.items-start {
  align-items: flex-start;
}

.items-end {
  align-items: flex-end;
}

.justify-center {
  justify-content: center;
}

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

.justify-end {
  justify-content: flex-end;
}

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.flex-1 {
  flex: 1;
}

.flex-wrap {
  flex-wrap: wrap;
}

/* Grid Utilities */
.grid {
  display: grid;
}

.grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

@media (min-width: 640px) {
  .sm\:grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .sm\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

@media (min-width: 768px) {
  .md\:grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .md\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .md\:grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .lg\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .lg\:grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

/* Grid Column Span */
.col-span-1 { grid-column: span 1 / span 1; }
.col-span-2 { grid-column: span 2 / span 2; }
.col-span-3 { grid-column: span 3 / span 3; }
.col-span-4 { grid-column: span 4 / span 4; }
.col-span-full { grid-column: 1 / -1; }

@media (min-width: 768px) {
  .md\:col-span-1 { grid-column: span 1 / span 1; }
  .md\:col-span-2 { grid-column: span 2 / span 2; }
  .md\:col-span-3 { grid-column: span 3 / span 3; }
  .md\:col-span-4 { grid-column: span 4 / span 4; }
}

@media (min-width: 1024px) {
  .lg\:col-span-1 { grid-column: span 1 / span 1; }
  .lg\:col-span-2 { grid-column: span 2 / span 2; }
  .lg\:col-span-3 { grid-column: span 3 / span 3; }
  .lg\:col-span-4 { grid-column: span 4 / span 4; }
}

/* Spacing Utilities */
.m-0 { margin: 0; }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.my-4 { margin-top: var(--space-4); margin-bottom: var(--space-4); }
.my-8 { margin-top: var(--space-8); margin-bottom: var(--space-8); }

.p-0 { padding: 0; }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }
.p-8 { padding: var(--space-8); }
.py-4 { padding-top: var(--space-4); padding-bottom: var(--space-4); }
.py-8 { padding-top: var(--space-8); padding-bottom: var(--space-8); }
.py-12 { padding-top: var(--space-12); padding-bottom: var(--space-12); }
.py-16 { padding-top: var(--space-16); padding-bottom: var(--space-16); }
.py-20 { padding-top: var(--space-20); padding-bottom: var(--space-20); }
.px-4 { padding-left: var(--space-4); padding-right: var(--space-4); }
.px-6 { padding-left: var(--space-6); padding-right: var(--space-6); }

/* Text Utilities */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-base { font-size: var(--text-base); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-2xl { font-size: var(--text-2xl); }
.text-3xl { font-size: var(--text-3xl); }
.text-4xl { font-size: var(--text-4xl); }

.font-normal { font-weight: var(--font-normal); }
.font-medium { font-weight: var(--font-medium); }
.font-semibold { font-weight: var(--font-semibold); }
.font-bold { font-weight: var(--font-bold); }

.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-accent { color: var(--color-accent); }
.text-muted { color: var(--color-text-muted); }
.text-light { color: var(--color-text-light); }

.uppercase { text-transform: uppercase; }
.capitalize { text-transform: capitalize; }

.tracking-wide { letter-spacing: 0.025em; }
.tracking-wider { letter-spacing: 0.05em; }

/* Display Utilities */
.hidden { display: none; }
.block { display: block; }
.inline-block { display: inline-block; }

@media (min-width: 640px) {
  .sm\:hidden { display: none; }
  .sm\:block { display: block; }
  .sm\:flex { display: flex; }
}

@media (min-width: 768px) {
  .md\:hidden { display: none; }
  .md\:block { display: block; }
  .md\:flex { display: flex; }
}

@media (min-width: 1024px) {
  .lg\:hidden { display: none; }
  .lg\:block { display: block; }
  .lg\:flex { display: flex; }
}

/* Background Utilities */
.bg-white { background-color: var(--color-surface); }
.bg-primary { background-color: var(--color-primary); }
.bg-primary-light { background-color: var(--color-primary-bg); }
.bg-secondary { background-color: var(--color-secondary); }
.bg-secondary-light { background-color: var(--color-secondary-bg); }
.bg-accent { background-color: var(--color-accent); }
.bg-accent-light { background-color: var(--color-accent-bg); }

/* Border Utilities */
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-2xl { border-radius: var(--radius-2xl); }
.rounded-full { border-radius: var(--radius-full); }

.border { border: 1px solid var(--color-border); }
.border-2 { border: 2px solid var(--color-border); }

/* Shadow Utilities */
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }
.shadow-card { box-shadow: var(--shadow-card); }

/* Position Utilities */
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; }

.inset-0 { top: 0; right: 0; bottom: 0; left: 0; }
.top-0 { top: 0; }
.right-0 { right: 0; }
.bottom-0 { bottom: 0; }
.left-0 { left: 0; }

/* Overflow Utilities */
.overflow-hidden { overflow: hidden; }
.overflow-auto { overflow: auto; }
.overflow-x-auto { overflow-x: auto; }

/* Width/Height Utilities */
.w-full { width: 100%; }
.h-full { height: 100%; }
.min-h-screen { min-height: 100vh; }

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

/* Cursor */
.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }

/* Opacity */
.opacity-0 { opacity: 0; }
.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }
.opacity-100 { opacity: 1; }

/* Transitions */
.transition {
  transition-property: color, background-color, border-color, box-shadow, transform, opacity;
  transition-timing-function: ease;
  transition-duration: 200ms;
}

.transition-transform {
  transition-property: transform;
  transition-timing-function: ease;
  transition-duration: 200ms;
}

/* Transform */
.scale-100 { transform: scale(1); }
.scale-105 { transform: scale(1.05); }

.hover\:scale-105:hover {
  transform: scale(1.05);
}

/* Number formatting for financial data */
.font-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}