/* ==========================================================================
   BASE & RESET STYLES
   Adhering to DESIGN.md Typography & Layout Rules
   ========================================================================== */

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

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

body {
  background-color: var(--color-canvas);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: var(--type-body-md-size);
  line-height: var(--type-body-md-lh);
  letter-spacing: var(--type-body-md-tracking);
  font-weight: var(--weight-regular);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* Accessible focus styling */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
}

/* Selection */
::selection {
  background-color: var(--color-primary);
  color: var(--color-on-primary);
}

/* Headings with Negative Letter Spacing (Key Design System Trait) */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  color: var(--color-ink);
  font-weight: var(--weight-medium);
}

.display-hero {
  font-size: clamp(48px, 9vw, var(--type-display-xxl-size));
  line-height: var(--type-display-xxl-lh);
  letter-spacing: clamp(-2.2px, -0.4vw, var(--type-display-xxl-tracking));
  font-weight: var(--weight-regular);
  text-transform: uppercase;
}

.display-lg {
  font-size: clamp(38px, 6vw, var(--type-display-lg-size));
  line-height: var(--type-display-lg-lh);
  letter-spacing: var(--type-display-lg-tracking);
  font-weight: var(--weight-light);
}

.heading-xl {
  font-size: clamp(30px, 4vw, var(--type-heading-xl-size));
  line-height: var(--type-heading-xl-lh);
  letter-spacing: var(--type-heading-xl-tracking);
  font-weight: var(--weight-regular);
}

.heading-lg {
  font-size: clamp(26px, 3.5vw, var(--type-heading-lg-size));
  line-height: var(--type-heading-lg-lh);
  letter-spacing: var(--type-heading-lg-tracking);
  font-weight: var(--weight-medium);
}

.heading-md {
  font-size: var(--type-heading-md-size);
  line-height: var(--type-heading-md-lh);
  letter-spacing: var(--type-heading-md-tracking);
  font-weight: var(--weight-medium);
}

.heading-sm {
  font-size: var(--type-heading-sm-size);
  line-height: var(--type-heading-sm-lh);
  letter-spacing: var(--type-heading-sm-tracking);
  font-weight: var(--weight-medium);
}

p {
  color: var(--color-body);
  font-size: var(--type-body-lg-size);
  line-height: 1.6;
  letter-spacing: -0.22px;
}

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

ul, ol {
  list-style: none;
}

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

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

.container-narrow {
  width: 100%;
  max-width: 960px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* Section Spacing (44px and 88px rhythm) */
.section {
  padding-top: var(--space-section);
  padding-bottom: var(--space-section);
  position: relative;
}

.section-band {
  padding-top: var(--space-band);
  padding-bottom: var(--space-band);
  position: relative;
}

/* Color-Blocked Bands */
.band-dark {
  background-color: var(--color-surface-alt);
  color: var(--color-muted);
}

.band-dark h2,
.band-dark h3,
.band-dark h4 {
  color: var(--color-muted);
}

.band-dark p {
  color: var(--color-neutral-2);
}

/* Screen reader utility */
.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;
}