/* ============================================= */
/* CSS Variables & Base Configuration */
/* ============================================= */
:root {
  /* Color Palette */
  --color-primary: #3498DB;
  --color-primary-light: #5DADE2;
  --color-primary-dark: #2980B9;
  --color-secondary: #FFD700;
  --color-secondary-light: #FFE44D;
  --color-secondary-dark: #E6C200;
  --color-neutral-light: #FDFEFE;
  --color-neutral-dark: #17202A;
  --color-body-bg: #FFFFFF;
  --color-text: #2C3E50;
  --color-text-light: #566573;
  --color-link: #2980B9;
  --color-link-hover: #1A5276;
  --color-success: #27AE60;
  --color-warning: #F39C12;
  --color-error: #E74C3C;

  /* Typography */
  --font-primary: 'Open Sans', sans-serif;
  --font-secondary: 'Roboto Slab', serif;
  --text-base-size: 1rem;
  --text-scale-ratio: 1.2;
  --text-xs: calc(var(--text-base-size) / var(--text-scale-ratio));
  --text-sm: var(--text-base-size);
  --text-md: calc(var(--text-base-size) * var(--text-scale-ratio));
  --text-lg: calc(var(--text-md) * var(--text-scale-ratio));
  --text-xl: calc(var(--text-lg) * var(--text-scale-ratio));
  --text-xxl: calc(var(--text-xl) * var(--text-scale-ratio));
  --text-xxxl: calc(var(--text-xxl) * var(--text-scale-ratio));

  /* Spacing */
  --space-unit: 1rem;
  --space-xxs: calc(0.25 * var(--space-unit));
  --space-xs: calc(0.5 * var(--space-unit));
  --space-sm: calc(0.75 * var(--space-unit));
  --space-md: calc(1.25 * var(--space-unit));
  --space-lg: calc(2 * var(--space-unit));
  --space-xl: calc(3.25 * var(--space-unit));
  --space-xxl: calc(5.25 * var(--space-unit));

  /* Borders & Radius */
  --border-radius-btn: 0.25rem;
  --border-radius-card: 0.5rem;
  --border-width: 1px;
  --border-style: solid;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.12);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 40px rgba(0,0,0,0.15);
  --shadow-inset: inset 0 2px 4px 0 rgba(0,0,0,0.05);

  /* Transitions */
  --transition-base: all 0.3s ease;
  --transition-fast: all 0.15s ease;
  --transition-slow: all 0.5s ease;

  /* Finance Theme Accents */
  --financial-glow: 0 0 8px rgba(255, 215, 0, 0.4);
  --growth-gradient: linear-gradient(135deg, rgba(52, 152, 219, 0.1) 0%, rgba(255, 215, 0, 0.1) 100%);
}

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

body {
  font-family: var(--font-primary);
  color: var(--color-text);
  background-color: var(--color-body-bg);
  line-height: 1.6;
  font-size: var(--text-sm);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-secondary);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--space-sm);
  color: var(--color-neutral-dark);
}

h1 { font-size: var(--text-xxxl); }
h2 { font-size: var(--text-xxl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }
h5 { font-size: var(--text-md); }
h6 { font-size: var(--text-sm); }

p {
  margin-bottom: var(--space-sm);
  color: var(--color-text-light);
}

a {
  color: var(--color-link);
  text-decoration: none;
  transition: var(--transition-fast);
  border-bottom: 1px solid transparent;
}

a:hover {
  color: var(--color-link-hover);
  border-bottom-color: currentColor;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ============================================= */
/* Buttons */
/* ============================================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--border-radius-btn);
  font-weight: 600;
  text-align: center;
  white-space: nowrap;
  vertical-align: middle;
  cursor: pointer;
  transition: var(--transition-base);
  border: var(--border-width) var(--border-style) transparent;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.btn-secondary:hover {
  background-color: var(--color-secondary-dark);
  box-shadow: var(--financial-glow);
}

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

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

/* ============================================= */
/* Cards */
/* ============================================= */
.card {
  background: white;
  border-radius: var(--border-radius-card);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  transition: var(--transition-base);
  position: relative;
  background-image: var(--growth-gradient);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

.card-header {
  padding: var(--space-md);
  border-bottom: var(--border-width) var(--border-style) rgba(0,0,0,0.05);
  background-color: var(--color-primary);
  color: white;
  font-family: var(--font-secondary);
}

.card-body {
  padding: var(--space-md);
}

/* ============================================= */
/* UI Components */
/* ============================================= */
/* Slider */
.slider-container {
  position: relative;
  overflow: hidden;
  border-radius: var(--border-radius-card);
}

.slider-track {
  display: flex;
  transition: transform 0.5s ease;
}

.slider-slide {
  min-width: 100%;
  padding: var(--space-xl) var(--space-lg);
  background-color: var(--color-neutral-light);
}

.slider-indicators {
  display: flex;
  justify-content: center;
  padding: var(--space-sm) 0;
}

.slider-indicator {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--color-primary-light);
  margin: 0 var(--space-xxs);
  cursor: pointer;
  transition: var(--transition-fast);
}

.slider-indicator.active {
  background-color: var(--color-primary);
  transform: scale(1.2);
}

/* Accordion */
.accordion-item {
  border-bottom: var(--border-width) var(--border-style) rgba(0,0,0,0.1);
}

.accordion-header {
  padding: var(--space-sm) 0;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
}

.accordion-header::after {
  content: '+';
  font-size: var(--text-lg);
  color: var(--color-primary);
  transition: var(--transition-fast);
}

.accordion-header.active::after {
  content: '-';
}

.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  padding: 0 var(--space-sm);
}

.accordion-content-inner {
  padding: var(--space-sm) 0 var(--space-md);
}

/* Tabs */
.tabs {
  display: flex;
  border-bottom: var(--border-width) var(--border-style) rgba(0,0,0,0.1);
  margin-bottom: var(--space-md);
}

.tab {
  padding: var(--space-xs) var(--space-md);
  cursor: pointer;
  position: relative;
  font-weight: 600;
  color: var(--color-text-light);
}

.tab::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transition: var(--transition-fast);
}

.tab.active {
  color: var(--color-primary);
}

.tab.active::after {
  transform: scaleX(1);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* ============================================= */
/* Layout Components */
/* ============================================= */
/* Header */
.header {
  position: sticky;
  top: 0;
  background-color: var(--color-body-bg);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  padding: var(--space-sm) 0;
}

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

.header-logo {
  height: 50px;
  transition: var(--transition-fast);
}

.header-logo:hover {
  opacity: 0.9;
}

.nav-list {
  display: flex;
  gap: var(--space-md);
  list-style: none;
}

.nav-link {
  font-weight: 600;
  padding: var(--space-xs) 0;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-secondary);
  transition: var(--transition-fast);
}

.nav-link:hover::after {
  width: 100%;
}

/* Footer */
.footer {
  background-color: var(--color-neutral-dark);
  color: var(--color-neutral-light);
  padding: var(--space-xl) 0 var(--space-md);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.footer-logo {
  height: 40px;
  margin-bottom: var(--space-md);
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}

.footer-link {
  color: var(--color-neutral-light);
  opacity: 0.8;
}

.footer-link:hover {
  opacity: 1;
  color: var(--color-secondary);
}

.social-links {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.social-icon {
  width: 24px;
  height: 24px;
  transition: var(--transition-fast);
}

.social-icon:hover {
  transform: translateY(-2px);
  opacity: 0.9;
}

.copyright {
  font-size: var(--text-xs);
  opacity: 0.6;
}

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

.form-label {
  display: block;
  margin-bottom: var(--space-xs);
  font-weight: 600;
}

.form-control {
  width: 100%;
  padding: var(--space-xs) var(--space-sm);
  border: var(--border-width) var(--border-style) rgba(0,0,0,0.1);
  border-radius: var(--border-radius-btn);
  font-family: var(--font-primary);
  transition: var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

/* ============================================= */
/* Utility Classes */
/* ============================================= */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section {
  padding: var(--space-xl) 0;
}

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

.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

/* ============================================= */
/* Animations */
/* ============================================= */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.fade-in {
  animation: fadeIn 0.5s ease forwards;
}

/* ============================================= */
/* Responsive Adjustments */
/* ============================================= */
@media (max-width: 768px) {
  :root {
    --text-base-size: 0.9375rem;
    --space-unit: 0.875rem;
  }

  .header-container {
    flex-direction: column;
    gap: var(--space-sm);
  }

  .nav-list {
    flex-direction: column;
    gap: var(--space-xs);
    align-items: center;
  }

  .tabs {
    flex-direction: column;
    border-bottom: none;
  }

  .tab {
    border-bottom: var(--border-width) var(--border-style) rgba(0,0,0,0.1);
  }

  .footer-nav {
    flex-direction: column;
    gap: var(--space-sm);
  }
}

@media (min-width: 1200px) {
  :root {
    --text-base-size: 1.0625rem;
  }
}