/* ==========================================================================
   Base Styles & Reset - OrbiFusionAI
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&display=swap');

*, *::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;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition-normal), color var(--transition-normal);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Typography Hierarchy */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.025em;
}

h1 {
  font-size: clamp(2.5rem, 5vw + 1rem, 4.25rem);
  font-weight: 800;
  letter-spacing: -0.035em;
}

h2 {
  font-size: clamp(1.85rem, 3.5vw + 0.5rem, 2.75rem);
  font-weight: 700;
  letter-spacing: -0.03em;
}

h3 {
  font-size: clamp(1.35rem, 2vw + 0.25rem, 1.75rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

h5 {
  font-size: 1.05rem;
  font-weight: 600;
}

h6 {
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-tertiary);
}

p {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.65;
}

p.lead {
  font-size: clamp(1.15rem, 1.5vw + 0.5rem, 1.35rem);
  color: var(--text-secondary);
  line-height: 1.55;
  font-weight: 400;
}

small, .text-sm {
  font-size: 0.875rem;
}

.text-xs {
  font-size: 0.75rem;
}

.font-mono {
  font-family: var(--font-mono);
}

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

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

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

ul, ol {
  list-style: none;
}

img, svg {
  display: block;
  max-width: 100%;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--max-width-site);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.container-narrow {
  width: 100%;
  max-width: var(--max-width-text);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.section {
  padding: 6rem 0;
  position: relative;
}

.section-lg {
  padding: 8rem 0;
}

.section-sm {
  padding: 4rem 0;
}

/* Section Headers */
.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 4rem auto;
}

.section-header.text-left {
  text-align: left;
  margin-left: 0;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  background: var(--accent-light);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  margin-bottom: 1.25rem;
  border: 1px solid var(--border-subtle);
}

.section-title {
  margin-bottom: 1.25rem;
}

.section-description {
  font-size: 1.15rem;
  color: var(--text-secondary);
}

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

.grid { display: grid; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 2rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .section { padding: 4rem 0; }
  .section-lg { padding: 5rem 0; }
}

/* Accessibility */
:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

.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;
}