/* ============================================================
   Kairos Tek — main.css
   Design tokens, CSS reset, base typography, layout helpers
   ============================================================ */

/* ─── Design Tokens ──────────────────────────────────────── */
:root {
  /* Colors */
  --color-blue:  #3b75f4;
  --color-navy:  #2b4bc2;
  --color-dark:  #080c16;
  --color-light: #ebefff;
  --color-white: #ffffff;

  /* Semantic aliases */
  --color-text-primary:   var(--color-dark);
  --color-text-on-dark:   var(--color-light);
  --color-text-on-blue:   var(--color-white);
  --color-bg-default:     var(--color-white);
  --color-bg-dark:        var(--color-dark);
  --color-bg-blue:        var(--color-blue);
  --color-bg-surface:     #f4f6fe;
  --color-border:         rgba(8, 12, 22, 0.12);
  --color-border-on-dark: rgba(235, 239, 255, 0.2);

  /* Typography */
  --font-sans: 'Inter', sans-serif;
  --font-heading: 'Space Grotesk', sans-serif;

  /* Spacing — 8pt scale */
  --space-1:  8px;
  --space-2:  16px;
  --space-3:  24px;
  --space-4:  32px;
  --space-5:  40px;
  --space-6:  48px;
  --space-8:  64px;
  --space-12: 96px;
  --space-16: 128px;

  /* Border radius */
  --radius-sm:  4px;
  --radius-md:  8px;
  --radius-btn: 6px;

  /* Transitions */
  --transition-fast: 150ms ease-out;
  --transition-med:  250ms ease-out;

  /* Containers */
  --container-max: 1200px;
  --container-pad: var(--space-4);
}

@media (max-width: 768px) {
  :root {
    --container-pad: var(--space-2);
  }
}

/* ─── CSS Reset ──────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg-default);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul, ol {
  list-style: none;
}

button {
  cursor: pointer;
  font-family: inherit;
  border: none;
  background: none;
}

/* ─── Base Typography ─────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); }
h3 { font-size: clamp(1.125rem, 2.5vw, 1.5rem); }

p {
  max-width: 68ch;
  line-height: 1.65;
}

strong { font-weight: 700; }

/* ─── Layout Helpers ──────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

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

/* ─── Section Spacing ─────────────────────────────────────── */
.section {
  padding-block: var(--space-12);
}

.section--sm {
  padding-block: var(--space-6);
}

@media (max-width: 768px) {
  .section { padding-block: var(--space-8); }
  .section--sm { padding-block: var(--space-4); }
}

/* ─── Color Modifiers ─────────────────────────────────────── */
.bg-dark {
  background-color: var(--color-bg-dark);
  color: var(--color-text-on-dark);
}

.bg-blue {
  background-color: var(--color-bg-blue);
  color: var(--color-text-on-blue);
}

.bg-light-surface {
  background-color: var(--color-bg-surface);
}

/* ─── Grid Utilities ──────────────────────────────────────── */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
  align-items: stretch;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
  align-items: stretch;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-3);
  align-items: stretch;
}

/* Equal-height cards: li is the grid item; card must fill it */
.grid-2 > li,
.grid-3 > li,
.grid-4 > li {
  display: flex;
  align-items: stretch;
}

.grid-2 > li > .product-card,
.grid-3 > li > *,
.grid-4 > li > .service-card {
  flex: 1;          /* fill all available height AND width */
  min-width: 0;     /* prevent overflow in narrow columns */
}

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

@media (max-width: 640px) {
  .grid-2,
  .grid-3,
  .grid-4 { grid-template-columns: 1fr; }
}

/* ─── Skip Navigation (M6 — WCAG 2.1 AA) ─────────────────── */
.skip-nav {
  position: absolute;
  top: -100%;
  left: var(--space-2);
  z-index: 9999;
  padding: var(--space-1) var(--space-3);
  background-color: var(--color-blue);
  color: var(--color-white);
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: var(--radius-btn);
  text-decoration: none;
  transition: top var(--transition-fast);
}

.skip-nav:focus {
  top: var(--space-2);
  outline: 3px solid var(--color-navy);
  outline-offset: 2px;
}

/* ─── Scroll Reveal Animations (A6 — Tetris Principle) ───── */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 400ms ease-out, transform 400ms ease-out;
}

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

.reveal--delay-1 { transition-delay: 80ms; }
.reveal--delay-2 { transition-delay: 160ms; }
.reveal--delay-3 { transition-delay: 240ms; }
.reveal--delay-4 { transition-delay: 320ms; }

/* ─── Hero Pixel Grid Decoration (A1 — Tetris Principle) ──── */
.hero__pixel-grid {
  position: absolute;
  top: 0;
  right: 0;
  width: 40%;
  height: 100%;
  pointer-events: none;
  opacity: 0.06;
  background-image:
    repeating-linear-gradient(
      0deg,
      var(--color-blue) 0px, var(--color-blue) 1px,
      transparent 1px, transparent 32px
    ),
    repeating-linear-gradient(
      90deg,
      var(--color-blue) 0px, var(--color-blue) 1px,
      transparent 1px, transparent 32px
    );
}

.hero {
  position: relative;
}

/* ─── Cookie Banner (C2 — GDPR) ──────────────────────────── */
#cookie-banner {
  position: fixed;
  bottom: var(--space-3);
  left: 50%;
  transform: translateX(-50%);
  z-index: 9000;
  width: calc(100% - var(--space-4) * 2);
  max-width: 680px;
  background-color: var(--color-dark);
  border: 1px solid var(--color-border-on-dark);
  border-radius: var(--radius-md);
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.4);
  transition: opacity var(--transition-med), transform var(--transition-med);
}

#cookie-banner.cookie-banner--hidden {
  opacity: 0;
  transform: translateX(-50%) translateY(12px);
  pointer-events: none;
}

.cookie-banner__inner {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-4);
  flex-wrap: wrap;
}

.cookie-banner__text {
  flex: 1;
  font-size: 0.875rem;
  color: var(--color-light);
  opacity: 0.75;
  line-height: 1.5;
  max-width: none;
}

.cookie-banner__link {
  color: var(--color-blue);
  text-decoration: underline;
}

.cookie-banner__actions {
  display: flex;
  gap: var(--space-2);
  flex-shrink: 0;
  flex-wrap: wrap;
}

.cookie-banner__btn {
  padding: 8px var(--space-2);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-btn);
  cursor: pointer;
  font-family: var(--font-sans);
  white-space: nowrap;
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.cookie-banner__btn--primary {
  background-color: var(--color-blue);
  color: var(--color-white);
  border: 1.5px solid var(--color-blue);
}

.cookie-banner__btn--primary:hover {
  background-color: var(--color-navy);
  border-color: var(--color-navy);
}

.cookie-banner__btn--ghost {
  background-color: transparent;
  color: var(--color-light);
  border: 1.5px solid var(--color-border-on-dark);
}

.cookie-banner__btn--ghost:hover {
  border-color: var(--color-light);
}

@media (max-width: 640px) {
  .cookie-banner__inner {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-2);
  }
  .cookie-banner__actions {
    flex-direction: column;
  }
}

/* ─── Contact Form (C6) ───────────────────────────────────── */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-top: var(--space-6);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.form-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-dark);
}

.form-input,
.form-textarea {
  width: 100%;
  padding: 12px var(--space-2);
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  color: var(--color-dark);
  background-color: var(--color-white);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  outline: none;
}

.form-input:focus,
.form-textarea:focus {
  border-color: var(--color-blue);
  box-shadow: 0 0 0 3px rgba(59, 117, 244, 0.15);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
  line-height: 1.55;
}

.form-checkbox-row {
  display: flex;
  align-items: flex-start;
  gap: var(--space-1);
}

.form-checkbox-row input[type="checkbox"] {
  margin-top: 3px;
  flex-shrink: 0;
  accent-color: var(--color-blue);
  width: 16px;
  height: 16px;
}

.form-checkbox-row label {
  font-size: 0.8125rem;
  color: rgba(8, 12, 22, 0.65);
  line-height: 1.5;
}

.form-checkbox-row a {
  color: var(--color-blue);
  text-decoration: underline;
}

.form-submit {
  align-self: flex-start;
}

.form-success {
  display: none;
  padding: var(--space-4);
  background-color: rgba(59, 117, 244, 0.08);
  border: 1px solid rgba(59, 117, 244, 0.25);
  border-radius: var(--radius-md);
  color: var(--color-dark);
  font-size: 0.9375rem;
}

.form-success.is-visible { display: block; }