/* Modern CSS Reset */
*, *::before, *::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  font-family: var(--font-family);
  font-size: var(--text-base);
  font-weight: var(--font-normal);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  transition: color var(--transition-normal), background-color var(--transition-normal);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--text-primary);
  margin-bottom: var(--space-4);
}

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-3xl); font-weight: var(--font-bold); }
h4 { font-size: var(--text-2xl); font-weight: var(--font-semibold); }
h5 { font-size: var(--text-xl); font-weight: var(--font-semibold); }
h6 { font-size: var(--text-lg); font-weight: var(--font-medium); }

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

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

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

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

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

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

/* Forms */
input, textarea, select, button {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

/* Focus States */
:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Container System */
.container {
  width: 100%;
  max-width: var(--container-xl);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 640px) {
  .container { padding: 0 var(--space-6); }
}

@media (min-width: 1024px) {
  .container { padding: 0 var(--space-8); }
}

/* Grid System */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
.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: 767px) {
  .grid-cols-2, .grid-cols-3, .grid-cols-4 {
    grid-template-columns: 1fr;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .grid-cols-3, .grid-cols-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Flexbox Utilities */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.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-start { justify-content: flex-start; }
.justify-end { justify-content: flex-end; }
.flex-1 { flex: 1; }

/* Spacing Utilities */
.mt-auto { margin-top: auto; }
.mb-auto { margin-bottom: auto; }
.ml-auto { margin-left: auto; }
.mr-auto { margin-right: auto; }

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

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

/* Responsive Display */
@media (max-width: 767px) {
  .hidden-mobile { display: none; }
  .block-mobile { display: block; }
}

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

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

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

/* Loading Screen */
.loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-primary);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: opacity var(--transition-normal);
}

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

.loading-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border-color);
  border-top: 3px solid var(--primary-blue);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: var(--space-4);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-screen p {
  color: var(--text-muted);
  font-size: var(--text-sm);
}

/* Utility Classes for Animations */
.fade-in {
  animation: fadeIn 0.6s ease-out forwards;
}

.slide-up {
  animation: slideUp 0.6s ease-out forwards;
}

.scale-in {
  animation: scaleIn 0.4s ease-out forwards;
}

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

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

/* Smooth Transitions */
.transition-all {
  transition: all var(--transition-normal);
}

.transition-colors {
  transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
}

/* 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;
}

/* Print Styles */
@media print {
  .no-print {
    display: none !important;
  }
  
  body {
    color: black;
    background: white;
  }
  
  a {
    text-decoration: underline;
  }
}