/* base.css - Modern reset, layout framework, container, and typography styling */

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

html {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: var(--lh-body);
  transition: background-color var(--transition-normal), color var(--transition-normal);
  overflow-x: hidden;
}

/* Typography elements */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: var(--lh-heading);
  color: var(--text-primary);
}

h1 { font-size: var(--text-hero); letter-spacing: -0.02em; }
h2 { font-size: var(--text-section-title); letter-spacing: -0.019em; }
h3 { font-size: var(--text-card-title); letter-spacing: -0.015em; }
h4 { font-size: var(--text-lg); }

p {
  font-size: var(--text-base);
  color: var(--text-secondary);
}

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

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

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--surface-color);
}

::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Layout Framework */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 5rem;
  padding-right: 5rem;
}

/* 12-Column Responsive Grid System */
.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 2rem;
}

.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); }
.grid-cols-6  { grid-template-columns: repeat(6, 1fr); }

/* Spacing classes - responsive sections */
.section {
  padding-top: var(--section-spacing-desktop);
  padding-bottom: var(--section-spacing-desktop);
  position: relative;
}
.section--no-top {
  padding-top: 0;
}
.section--surface {
  background: var(--surface-color);
}

@media (max-width: 1024px) {
  .section {
    padding-top: var(--section-spacing-tablet);
    padding-bottom: var(--section-spacing-tablet);
  }
  .container {
    padding-left: 2rem;
    padding-right: 2rem;
  }
  .grid {
    gap: 1.5rem;
  }
}

@media (max-width: 768px) {
  .section {
    padding-top: var(--section-spacing-mobile);
    padding-bottom: var(--section-spacing-mobile);
  }
  .container {
    padding-left: 1.25rem;
    padding-right: 1.25rem;
  }
  .grid {
    gap: 1rem;
  }
}

/* Standard structural helpers */
.col-span-12 { grid-column: span 12; }
.col-span-10 { grid-column: span 10; }
.col-span-8  { grid-column: span 8; }
.col-span-6  { grid-column: span 6; }
.col-span-4  { grid-column: span 4; }
.col-span-3  { grid-column: span 3; }
.col-span-2  { grid-column: span 2; }

@media (max-width: 1024px) {
  .col-span-md-12 { grid-column: span 12; }
  .col-span-md-6  { grid-column: span 6; }
  .col-span-md-4  { grid-column: span 4; }
}

@media (max-width: 768px) {
  .col-span-sm-12 { grid-column: span 12; }
  .col-span-sm-6  { grid-column: span 6; }
}

/* Flex Utilities */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.flex-wrap { flex-wrap: wrap; }
.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 0.75rem; }
.gap-4 { gap: 1rem; }
.gap-6 { gap: 1.5rem; }
.gap-8 { gap: 2rem; }

/* Text Utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-lg { font-size: var(--text-lg); }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }
.text-primary-color { color: var(--primary-color); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }

/* Sizes */
.text-base { font-size: var(--text-base); }
.text-success { color: var(--success); }
.font-semibold { font-weight: 600; }

/* Accent */
.accent-primary { accent-color: var(--primary-color); }

/* Border width */
.border-2 { border-width: 2px; }

/* Top positions */
.top-6 { top: 1.5rem; }
.top-8 { top: 2rem; }

/* Other Utility Classes */
.w-full { width: 100%; }
.w-auto { width: auto; }
.h-full { height: 100%; }
.relative { position: relative; }
.overflow-hidden { overflow: hidden; }
.mx-auto { margin-left: auto; margin-right: auto; }
.pointer-events-none { pointer-events: none; }

/* Overlay backdrops */
.backdrop {
  position: fixed;
  inset: 0;
  background: var(--overlay, rgba(0, 0, 0, 0.4));
  backdrop-filter: blur(4px);
  z-index: 900;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.backdrop.active {
  opacity: 1;
  visibility: visible;
}

/* Accessibility: Skip to Content */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-color);
  color: white;
  padding: 8px;
  z-index: 1000;
  transition: top 0.2s;
}
.skip-link:focus {
  top: 0;
}

/* Accessibility Focus States */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Additional Layout Utilities */
.d-none { display: none; }
.d-block { display: block; }
.d-inline-block { display: inline-block; }
.d-inline-flex { display: inline-flex; }
.d-grid { display: grid; }
.flex-1 { flex: 1; }
.flex-shrink-0 { flex-shrink: 0; }
.flex-grow { flex-grow: 1; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.items-stretch { align-items: stretch; }
.self-start { align-self: flex-start; }
.justify-end { justify-content: flex-end; }
.justify-around { justify-content: space-around; }
.justify-items-center { justify-items: center; }
.gap-0 { gap: 0; }
.gap-05 { gap: 0.125rem; }
.gap-5 { gap: 1.25rem; }

/* Spacing */
.m-0 { margin: 0; }
.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }
.mt-5 { margin-top: 1.25rem; }
.mt-6 { margin-top: 1.5rem; }
.mt-8 { margin-top: 2rem; }
.mt-10 { margin-top: 2.5rem; }
.mt-12 { margin-top: 3rem; }
.mt-16 { margin-top: 4rem; }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 0.75rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-5 { margin-bottom: 1.25rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mb-8 { margin-bottom: 2rem; }
.mb-10 { margin-bottom: 2.5rem; }
.mb-12 { margin-bottom: 3rem; }
.mb-16 { margin-bottom: 4rem; }
.mb-20 { margin-bottom: 5rem; }
.ml-auto { margin-left: auto; }
.ml-2 { margin-left: 0.5rem; }
.mr-auto { margin-right: auto; }

.p-0 { padding: 0; }
.p-1 { padding: 0.25rem; }
.p-2 { padding: 0.5rem; }
.p-3 { padding: 0.75rem; }
.p-4 { padding: 1rem; }
.p-5 { padding: 1.25rem; }
.p-6 { padding: 1.5rem; }
.p-8 { padding: 2rem; }
.py-1 { padding-top: 0.25rem; padding-bottom: 0.25rem; }
.py-2 { padding-top: 0.5rem; padding-bottom: 0.5rem; }
.py-3 { padding-top: 0.75rem; padding-bottom: 0.75rem; }
.py-4 { padding-top: 1rem; padding-bottom: 1rem; }
.px-1 { padding-left: 0.25rem; padding-right: 0.25rem; }
.px-2 { padding-left: 0.5rem; padding-right: 0.5rem; }
.px-3 { padding-left: 0.75rem; padding-right: 0.75rem; }
.px-4 { padding-left: 1rem; padding-right: 1rem; }
.pt-2 { padding-top: 0.5rem; }
.pb-2 { padding-bottom: 0.5rem; }

/* Extended Positioning */
.pos-absolute { position: absolute; }
.pos-fixed { position: fixed; }
.pos-sticky { position: sticky; }
.top-0 { top: 0; }
.right-0 { right: 0; }
.bottom-0 { bottom: 0; }
.left-0 { left: 0; }

/* Borders */
.border { border: 1px solid var(--border-color); }
.border-0 { border: 0; }
.border-t { border-top: 1px solid var(--border-color); }
.border-b { border-bottom: 1px solid var(--border-color); }
.border-b-0 { border-bottom: none; }
.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-full { border-radius: var(--radius-full); }

/* Other */
.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.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;
}
.list-none { list-style: none; }
.no-underline { text-decoration: none; }
.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }
.select-none { user-select: none; }
.object-cover { object-fit: cover; }
.opacity-0 { opacity: 0; }
.opacity-50 { opacity: 0.5; }
.opacity-100 { opacity: 1; }
.z-1 { z-index: 1; }
.z-10 { z-index: 10; }
.z-50 { z-index: 50; }
.z-100 { z-index: 100; }

/* Focus ring */
.focus-ring:focus {
  outline: none;
  box-shadow: 0 0 0 4px var(--primary-glow);
}

/* Shadow utilities */
.shadow-xl { box-shadow: var(--shadow-xl); }

/* ==========================================
   SCROLL-REVEAL ENTRANCE ANIMATIONS
   Principle: Feedback & Motion — elements
   animate in as users scroll, confirming
   page progression and guiding attention.
   ========================================== */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.55s cubic-bezier(0.4,0,0.2,1), transform 0.55s cubic-bezier(0.4,0,0.2,1);
}
[data-reveal].revealed {
  opacity: 1;
  transform: translateY(0);
}
/* Stagger siblings inside a grid/flex parent */
[data-reveal]:nth-child(2) { transition-delay: 80ms; }
[data-reveal]:nth-child(3) { transition-delay: 160ms; }
[data-reveal]:nth-child(4) { transition-delay: 240ms; }

/* Card image zoom on hover (micro-interaction) */
.card-interactive:hover img,
.card-interactive:focus-within img {
  transform: scale(1.04);
}

/* ==========================================
   RESPONSIVE GRID UTILITY CLASSES
   ========================================== */
.responsive-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}
.responsive-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

@media (max-width: 991px) {
  .responsive-grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}
@media (max-width: 768px) {
  .responsive-grid-2,
  .responsive-grid-3 {
    grid-template-columns: 1fr;
  }
  .responsive-grid-2.form-grid {
    gap: 1rem;
  }
}