/* =========================================================================
   AAB Inventions LLC — styles.css
   Single-page static site. No build step, no external assets.
   ========================================================================= */

/* ---- Design tokens ---------------------------------------------------- */
:root {
  --bg: #ffffff;
  --bg-subtle: #f6f7f9;
  --text: #10151c;
  --text-muted: #55606d;
  --border: #e6e9ee;
  --accent: #1d4ed8;
  --accent-strong: #1e40af;
  --accent-contrast: #ffffff;
  --focus: #1d4ed8;

  --container: 66rem;
  --narrow: 44rem;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
    "Liberation Mono", monospace;

  --radius: 10px;
  --shadow-sm: 0 1px 2px rgba(16, 21, 28, 0.05);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c0f14;
    --bg-subtle: #12161d;
    --text: #eef1f6;
    --text-muted: #9aa4b2;
    --border: #232a34;
    --accent: #7aa2ff;
    --accent-strong: #9cbaff;
    --accent-contrast: #0c0f14;
    --focus: #7aa2ff;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  }
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, p { margin: 0; }

a { color: var(--accent); }

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

/* ---- Layout helpers --------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.section {
  padding-block: clamp(3.5rem, 9vw, 7rem);
}

.section-alt {
  background: var(--bg-subtle);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

/* ---- Accessibility: skip link & focus --------------------------------- */
.skip-link {
  position: absolute;
  left: 1rem;
  top: -3.5rem;
  z-index: 100;
  padding: 0.6rem 1rem;
  border-radius: var(--radius);
  background: var(--accent);
  color: var(--accent-contrast);
  text-decoration: none;
  transition: top 0.15s ease;
}
.skip-link:focus {
  top: 1rem;
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

a:focus-visible,
button:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---- Header ----------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 4rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  color: var(--text);
  font-weight: 650;
  letter-spacing: -0.01em;
}
.brand-name { font-size: 1.05rem; }

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}
.site-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 550;
  padding: 0.25rem 0;
}
.site-nav a:hover { color: var(--text); }
.site-nav a:focus-visible { color: var(--text); }

/* ---- Shared type ------------------------------------------------------ */
.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(1.5rem, 3.5vw, 2rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  font-weight: 680;
  margin-bottom: 1.1rem;
}

.prose {
  color: var(--text-muted);
  font-size: 1.075rem;
  max-width: 40rem;
}

/* Anchor offset so the sticky header never covers section headings */
#about, #contact { scroll-margin-top: 5rem; }

/* ---- Hero ------------------------------------------------------------- */
.hero {
  position: relative;
  padding-block: clamp(4rem, 12vw, 8.5rem);
  overflow: hidden;
}

/* Subtle technical dot grid — decorative only */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  background-image: radial-gradient(currentColor 1px, transparent 1px);
  background-size: 22px 22px;
  color: var(--border);
  opacity: 0.55;
  -webkit-mask-image: radial-gradient(75% 60% at 50% 30%, #000 0%, transparent 78%);
  mask-image: radial-gradient(75% 60% at 50% 30%, #000 0%, transparent 78%);
  pointer-events: none;
}

.hero-inner { position: relative; z-index: 1; }

.hero-title {
  font-size: clamp(2.5rem, 7vw, 4.25rem);
  line-height: 1.04;
  letter-spacing: -0.03em;
  font-weight: 720;
  margin-bottom: 1.1rem;
  overflow-wrap: break-word;
}

.hero-tagline {
  font-size: clamp(1.25rem, 3.2vw, 1.6rem);
  line-height: 1.35;
  font-weight: 560;
  color: var(--text);
  margin-bottom: 1rem;
}

.hero-sub {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 38rem;
  margin-bottom: 2rem;
}

.hero-actions { margin: 0; }

/* ---- Buttons ---------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.9rem;
  padding: 0.6rem 1.4rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  border: 1px solid transparent;
  transition: background-color 0.15s ease, transform 0.05s ease, box-shadow 0.15s ease;
}
.btn-primary {
  background: var(--accent);
  color: var(--accent-contrast);
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { background: var(--accent-strong); }
.btn-primary:active { transform: translateY(1px); }

/* ---- Contact ---------------------------------------------------------- */
.contact-email {
  margin-top: 1.5rem;
  font-size: clamp(1.15rem, 2.6vw, 1.4rem);
  font-weight: 600;
  letter-spacing: -0.01em;
}
.contact-email a {
  text-decoration: none;
  border-bottom: 2px solid var(--accent);
  border-bottom: 2px solid color-mix(in srgb, var(--accent) 40%, transparent);
  padding-bottom: 2px;
}
.contact-email a:hover { border-bottom-color: var(--accent); }

/* ---- Footer ----------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding-block: 2.25rem;
}
/* The Contact panel's bottom border already meets the footer — avoid a doubled 2px seam. */
main + .site-footer { border-top: 0; }
.footer-copy {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ---- Small screens ---------------------------------------------------- */
@media (max-width: 30rem) {
  .site-nav { gap: 1.25rem; }
  .brand-name { font-size: 1rem; }
}