/* ==========================================================================
   A2B SOLUTIONS — CENTRAL STYLESHEET
   All colors, type, and spacing are defined as CSS variables in :root below.
   To re-theme the entire site, change the values in :root — nothing else
   needs to be touched.
   ========================================================================== */

:root {
  /* ---- Palette ---- */
  --color-bg: #0f1b2d;             /* page background — blueprint navy */
  --color-bg-elevated: #16253c;    /* card / panel background */
  --color-bg-elevated-2: #1c2e48;  /* hover / secondary panel */
  --color-grid-line: #2a3f5a;      /* hairline rules, grid pattern */
  --color-accent: #c98a3b;         /* brass/amber — signature accent, use sparingly */
  --color-accent-soft: rgba(201, 138, 59, 0.14);
  --color-accent-hover: #dda257;
  --color-text: #edeae2;           /* primary text — warm paper white */
  --color-text-muted: #8fa3bd;     /* secondary text */
  --color-text-faint: #5b6f8a;     /* tertiary / disabled text */
  --color-border: #2a3f5a;

  /* ---- Type ---- */
  --font-display: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;
  --font-body: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, sans-serif;

  --fs-hero: clamp(2.25rem, 5vw + 1rem, 4rem);
  --fs-h1: clamp(1.75rem, 3vw + 1rem, 2.5rem);
  --fs-h2: clamp(1.35rem, 2vw + 0.8rem, 1.75rem);
  --fs-body: 1rem;
  --fs-small: 0.875rem;
  --fs-eyebrow: 0.8125rem;

  /* ---- Spacing ---- */
  --space-3xs: 0.25rem;
  --space-2xs: 0.5rem;
  --space-xs: 0.75rem;
  --space-sm: 1rem;
  --space-md: 1.75rem;
  --space-lg: 3rem;
  --space-xl: 5rem;
  --space-2xl: 7.5rem;

  /* ---- Layout ---- */
  --container-width: 1120px;
  --radius-sm: 3px;
  --radius-md: 6px;
  --border-hairline: 1px solid var(--color-border);

  /* ---- Motion ---- */
  --ease-standard: cubic-bezier(0.2, 0.6, 0.2, 1);
  --duration-standard: 0.5s;
}

/* ==========================================================================
   Reset
   ========================================================================== */

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

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  margin: 0;
  background-color: var(--color-bg);
  background-image:
    linear-gradient(var(--color-grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-grid-line) 1px, transparent 1px);
  background-size: 48px 48px;
  background-position: center top;
  background-attachment: fixed;
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* the grid pattern above is deliberately faint via low-contrast line color;
   this overlay knocks it back further so it reads as texture, not clutter */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background: radial-gradient(ellipse at top, rgba(15, 27, 45, 0) 0%, var(--color-bg) 78%);
  pointer-events: none;
  z-index: 0;
}

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

a {
  color: inherit;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  margin: 0;
  letter-spacing: -0.01em;
}

p {
  margin: 0;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

button {
  font-family: inherit;
}

/* Visible keyboard focus everywhere */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
  position: relative;
  z-index: 1;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ==========================================================================
   Eyebrow / labels — technical annotation style
   ========================================================================== */

.eyebrow {
  font-family: var(--font-display);
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  background: var(--color-accent);
  display: inline-block;
}

/* ==========================================================================
   Header / Nav
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15, 27, 45, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: var(--border-hairline);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-sm);
  padding-bottom: var(--space-sm);
}

.wordmark {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
  text-decoration: none;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: var(--space-2xs);
}

.wordmark .mark {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  gap: var(--space-lg);
  align-items: center;
}

.nav-links a {
  font-family: var(--font-display);
  font-size: var(--fs-small);
  letter-spacing: 0.03em;
  text-decoration: none;
  color: var(--color-text-muted);
  padding: var(--space-3xs) 0;
  border-bottom: 1px solid transparent;
  transition: color var(--duration-standard) var(--ease-standard),
    border-color var(--duration-standard) var(--ease-standard);
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--color-text);
  border-color: var(--color-accent);
}

.nav-toggle {
  display: none;
  background: none;
  border: var(--border-hairline);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  padding: var(--space-2xs) var(--space-xs);
  cursor: pointer;
  font-family: var(--font-display);
  font-size: var(--fs-small);
}

@media (max-width: 720px) {
  .nav-toggle {
    display: inline-flex;
  }
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg-elevated);
    border-bottom: var(--border-hairline);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: var(--space-sm) var(--space-md);
    display: none;
  }
  .nav-links.is-open {
    display: flex;
  }
  .nav-links a {
    width: 100%;
    padding: var(--space-sm) 0;
    border-bottom: var(--border-hairline);
  }
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  font-family: var(--font-display);
  font-size: var(--fs-small);
  letter-spacing: 0.03em;
  text-decoration: none;
  padding: 0.7rem 1.25rem;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background var(--duration-standard) var(--ease-standard),
    border-color var(--duration-standard) var(--ease-standard),
    color var(--duration-standard) var(--ease-standard),
    transform 0.15s var(--ease-standard);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-bg);
}

.btn-primary:hover {
  background: var(--color-accent-hover);
}

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

.btn-secondary:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  padding: var(--space-2xl) 0 var(--space-xl);
}

.hero-inner {
  max-width: 760px;
}

.hero h1 {
  font-size: var(--fs-hero);
  margin-top: var(--space-sm);
  color: var(--color-text);
}

.hero h1 .accent {
  color: var(--color-accent);
}

.hero p.lede {
  font-family: var(--font-body);
  font-size: 1.125rem;
  color: var(--color-text-muted);
  max-width: 620px;
  margin-top: var(--space-md);
}

.hero-actions {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
  flex-wrap: wrap;
}

/* ==========================================================================
   Schematic diagram (signature element)
   ========================================================================== */

.schematic-wrap {
  margin-top: var(--space-2xl);
  border: var(--border-hairline);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  padding: var(--space-lg) var(--space-md) var(--space-md);
  overflow-x: auto;
}

.schematic-wrap svg {
  width: 100%;
  height: auto;
  min-width: 640px;
  display: block;
}

.schematic-caption {
  font-family: var(--font-display);
  font-size: var(--fs-small);
  color: var(--color-text-faint);
  margin-top: var(--space-sm);
  text-align: center;
}

.schem-box-label {
  font-family: var(--font-body);
  font-size: 13px;
}

.schem-col-label {
  font-family: var(--font-display);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.schem-line {
  stroke: var(--color-accent);
  stroke-width: 1.5;
  fill: none;
}

.schem-box-before {
  fill: var(--color-bg);
  stroke: var(--color-text-faint);
  stroke-width: 1;
}

.schem-box-after {
  fill: var(--color-accent-soft);
  stroke: var(--color-accent);
  stroke-width: 1;
}

/* animated draw-in for the connecting lines; harmless if JS doesn't run */
.schem-line {
  stroke-dasharray: 240;
  stroke-dashoffset: 240;
  transition: stroke-dashoffset 1.1s var(--ease-standard);
}

.schematic-wrap.is-visible .schem-line {
  stroke-dashoffset: 0;
}

@media (prefers-reduced-motion: reduce) {
  .schem-line {
    stroke-dashoffset: 0;
    transition: none;
  }
}

/* ==========================================================================
   Sections / generic
   ========================================================================== */

.section {
  padding: var(--space-xl) 0;
  border-top: var(--border-hairline);
}

.section-head {
  max-width: 640px;
  margin-bottom: var(--space-lg);
}

.section-head h2 {
  font-size: var(--fs-h1);
  margin-top: var(--space-sm);
}

.section-head p {
  color: var(--color-text-muted);
  margin-top: var(--space-sm);
  font-size: 1.05rem;
}

/* ==========================================================================
   Audience cards (home)
   ========================================================================== */

.audience-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
}

@media (max-width: 720px) {
  .audience-grid {
    grid-template-columns: 1fr;
  }
}

.audience-card {
  border: var(--border-hairline);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  padding: var(--space-lg);
}

.audience-card .eyebrow {
  margin-bottom: var(--space-sm);
}

.audience-card h3 {
  font-size: var(--fs-h2);
  margin-bottom: var(--space-sm);
}

.audience-card p {
  color: var(--color-text-muted);
}

.audience-card ul {
  margin-top: var(--space-md);
  display: flex;
  flex-direction: column;
  gap: var(--space-2xs);
}

.audience-card li {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
  padding-left: var(--space-md);
  position: relative;
}

.audience-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 6px;
  height: 1px;
  background: var(--color-accent);
}

/* ==========================================================================
   Service blocks (services.html)
   ========================================================================== */

.service-block {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: var(--space-lg);
  padding: var(--space-lg) 0;
  border-top: var(--border-hairline);
}

.service-block:first-of-type {
  border-top: none;
}

@media (max-width: 720px) {
  .service-block {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }
}

.service-block .sec-num {
  font-family: var(--font-display);
  color: var(--color-accent);
  font-size: var(--fs-small);
  letter-spacing: 0.08em;
}

.service-block h3 {
  font-size: var(--fs-h2);
  margin-bottom: var(--space-sm);
}

.service-block p.desc {
  color: var(--color-text-muted);
  max-width: 620px;
  margin-bottom: var(--space-md);
}

.service-block ul {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-2xs) var(--space-lg);
}

@media (max-width: 560px) {
  .service-block ul {
    grid-template-columns: 1fr;
  }
}

.service-block li {
  font-size: var(--fs-small);
  color: var(--color-text);
  padding-left: var(--space-md);
  position: relative;
}

.service-block li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 6px;
  height: 1px;
  background: var(--color-accent);
}

/* ==========================================================================
   Case study cards
   ========================================================================== */

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

@media (max-width: 900px) {
  .case-grid {
    grid-template-columns: 1fr;
  }
}

.case-card {
  border: var(--border-hairline);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  padding: var(--space-md);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.case-tag {
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.case-card h3 {
  font-size: 1.1rem;
  line-height: 1.3;
}

.case-card p {
  color: var(--color-text-muted);
  font-size: var(--fs-small);
  flex-grow: 1;
}

.case-status {
  font-family: var(--font-display);
  font-size: 11px;
  color: var(--color-text-faint);
  border-top: var(--border-hairline);
  padding-top: var(--space-sm);
}

/* ==========================================================================
   About / contact
   ========================================================================== */

.about-copy {
  max-width: 680px;
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.about-copy p {
  color: var(--color-text-muted);
  font-size: 1.05rem;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: start;
}

@media (max-width: 800px) {
  .contact-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }
}

.contact-direct {
  border: var(--border-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  background: var(--color-bg-elevated);
}

.contact-direct .eyebrow {
  margin-bottom: var(--space-sm);
}

.contact-direct a.email {
  font-family: var(--font-display);
  color: var(--color-accent);
  text-decoration: none;
  font-size: 1.05rem;
  word-break: break-all;
}

form.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.field {
  display: flex;
  flex-direction: column;
  gap: var(--space-3xs);
}

.field label {
  font-family: var(--font-display);
  font-size: 12px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.field input,
.field textarea {
  background: var(--color-bg-elevated);
  border: var(--border-hairline);
  border-radius: var(--radius-sm);
  padding: 0.7rem 0.85rem;
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  resize: vertical;
}

.field input::placeholder,
.field textarea::placeholder {
  color: var(--color-text-faint);
}

.field input:focus,
.field textarea:focus {
  border-color: var(--color-accent);
  outline: none;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  border-top: var(--border-hairline);
  padding: var(--space-lg) 0;
  margin-top: var(--space-xl);
}

.site-footer .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.site-footer p {
  font-family: var(--font-display);
  font-size: var(--fs-small);
  color: var(--color-text-faint);
}

.footer-links {
  display: flex;
  gap: var(--space-md);
}

.footer-links a {
  font-family: var(--font-display);
  font-size: var(--fs-small);
  color: var(--color-text-faint);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--color-accent);
}

/* ==========================================================================
   Scroll reveal utility (progressive enhancement via JS)
   ========================================================================== */

.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity var(--duration-standard) var(--ease-standard),
    transform var(--duration-standard) var(--ease-standard);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
  }
}