/* Main Stylesheet - Shared Components & Base Styles */
/* Import Order: Variables → Reset → Base → Layout → Components → Utilities */

@import './variables.css';

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

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

body {
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* ========== BASE TYPOGRAPHY ========== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  font-weight: 700;
  line-height: var(--line-height-tight);
  color: var(--color-secondary);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
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-md);
}

.text-center { text-align: center; }
.text-light { color: var(--color-text-light); }
.text-primary { color: var(--color-primary); }

/* ========== LAYOUT ========== */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

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

main {
  flex: 1;
}

section {
  padding: var(--spacing-4xl) 0;
}

/* ========== NAVIGATION ========== */
.nav {
  background-color: var(--color-background);
  border-bottom: 1px solid var(--color-border-light);
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.nav__logo {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-secondary);
}

.nav__logo:hover {
  color: var(--color-primary);
}

.nav__menu {
  display: flex;
  gap: var(--spacing-xl);
}

.nav__link {
  font-weight: 500;
  color: var(--color-text);
  padding: var(--spacing-sm) 0;
  position: relative;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition-base);
}

.nav__link:hover::after,
.nav__link--active::after {
  width: 100%;
}

.nav__link:hover,
.nav__link--active {
  color: var(--color-primary);
}

/* ========== FOOTER ========== */
.footer {
  background-color: var(--color-secondary);
  color: var(--color-text-inverse);
  padding: var(--spacing-3xl) 0;
  margin-top: auto;
}

.footer__container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  text-align: center;
}

.footer__social {
  display: flex;
  justify-content: center;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
  flex-wrap: wrap;
}

.footer__social-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background-color: var(--color-background);
  color: var(--color-text);
  border-radius: var(--border-radius-full);
  transition: all var(--transition-base);
}

.footer__social-link:hover {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  transform: translateY(-2px);
}

.footer__social-link svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

.footer__copyright {
  font-size: var(--font-size-sm);
  color: var(--color-text-light);
  opacity: 0.8;
}

/* ========== BUTTONS ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  font-size: var(--font-size-base);
  font-weight: 600;
  text-align: center;
  border-radius: var(--border-radius-md);
  transition: all var(--transition-base);
  cursor: pointer;
  border: 2px solid transparent;
}

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

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

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

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

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

.btn--ghost {
  background-color: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn--ghost:hover {
  background-color: var(--color-background-alt);
  border-color: var(--color-text-light);
}

/* ========== CARDS ========== */
.card {
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-xl);
  transition: all var(--transition-base);
}

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

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

.card__icon {
  width: 48px;
  height: 48px;
  margin-bottom: var(--spacing-md);
  color: var(--color-primary);
}

.card__title {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-sm);
}

.card__content {
  color: var(--color-text-light);
  line-height: var(--line-height-relaxed);
}

.card--highlighted {
  border-color: var(--color-primary);
  border-width: 2px;
}

/* ========== GRID LAYOUTS ========== */
.grid {
  display: grid;
  gap: var(--spacing-xl);
}

.grid--2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid--3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

/* ========== SECTION HEADERS ========== */
.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-header__title {
  margin-bottom: var(--spacing-md);
}

.section-header__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-light);
  max-width: 48rem;
  margin: 0 auto;
}

/* ========== UTILITIES ========== */
.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;
}

.mb-0 { margin-bottom: 0; }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.mt-0 { margin-top: 0; }
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

/* ========== RESPONSIVE ========== */
@media (max-width: var(--breakpoint-md)) {
  h1 { font-size: var(--font-size-4xl); }
  h2 { font-size: var(--font-size-3xl); }
  h3 { font-size: var(--font-size-xl); }
  
  section {
    padding: var(--spacing-3xl) 0;
  }
  
  .nav__menu {
    gap: var(--spacing-lg);
  }
}

@media (max-width: var(--breakpoint-sm)) {
  h1 { font-size: var(--font-size-3xl); }
  h2 { font-size: var(--font-size-2xl); }
  
  .container {
    padding: 0 var(--spacing-md);
  }
  
  .nav__menu {
    gap: var(--spacing-md);
  }
}