/* ==========================================================================
   Kharkevich Engineering Lab — Whiteboard Sketch Design System
   Domain: ai.kharkevich.com (Schema 2: Whiteboard Canvas + Preserved Dark Header & Footer)
   ========================================================================== */

:root {
  /* Whiteboard Canvas Colors */
  --canvas-bg: #ffffff;
  --canvas-alt: #fafafc;
  --marker-black: #18181b;
  --marker-charcoal: #27272a;
  --marker-slate: #475569;
  --marker-gray: #71717a;
  
  /* Brand Accents */
  --marker-blue: #0284c7;
  --marker-cyan: #06b6d4;
  --marker-canadian-red: #ef4444;
  --marker-yellow: #f59e0b;
  --marker-green: #10b981;

  /* Header & Footer Dark Theme (Preserved) */
  --header-bg: rgba(9, 13, 22, 0.92);
  --footer-bg: #090d16;
  --dark-text-primary: #f8fafc;
  --dark-text-secondary: #94a3b8;
  --dark-border: rgba(255, 255, 255, 0.08);

  /* Typography */
  --font-sketch: 'Architects Daughter', cursive, sans-serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-heading: 'Outfit', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Layout */
  --container-max: 1180px;
  --header-height: 75px;
  --radius-sketch-box: 255px 15px 225px 15px / 15px 225px 15px 255px;
  --radius-sketch-pill: 20px 255px 20px 255px / 255px 20px 255px 20px;
  --radius-subtle: 8px;

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-size: 16px;
  background-color: var(--canvas-bg);
  color: var(--marker-black);
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body.sketch-theme {
  position: relative;
  min-height: 100vh;
  background-color: var(--canvas-bg);
  overflow-x: hidden;
}

.whiteboard-canvas {
  position: relative;
  background-color: var(--canvas-bg);
  padding-top: var(--header-height);
  z-index: 1;
}

.whiteboard-canvas::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: radial-gradient(#c9d5e0 1.2px, transparent 1.2px);
  background-size: 24px 24px;
  pointer-events: none;
  z-index: 0;
  mix-blend-mode: multiply;
}

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

/* ==========================================================================
   PRESERVED SLEEK DARK HEADER
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background-color: var(--header-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--dark-border);
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
  transform: translateZ(0);
  will-change: transform;
  transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

.site-header.scrolled {
  background-color: rgba(9, 13, 22, 0.96);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.25);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--dark-text-primary);
  transition: opacity var(--transition-fast);
}

.brand-logo:hover {
  opacity: 0.9;
}

.logo-mark {
  width: 46px;
  height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.logo-mark.sm {
  width: 34px;
  height: 34px;
}

.logo-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.logo-svg {
  width: 100%;
  height: 100%;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.company-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.125rem;
  text-transform: uppercase;
  letter-spacing: -0.02em;
  color: #ffffff;
  line-height: 1.1;
}

.company-sub {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #38bdf8;
  font-weight: 500;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-link {
  color: var(--dark-text-secondary);
  text-decoration: none;
  font-size: 0.9375rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
  color: var(--dark-text-primary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-body);
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), background-color var(--transition-normal);
  line-height: 1;
  transform: translate3d(0, 0, 0);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.btn-primary {
  background-color: rgba(255, 255, 255, 0.02);
  color: var(--dark-text-secondary);
  border-radius: var(--radius-subtle);
  border: 1px solid var(--dark-border);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  padding: 0.6rem 0.95rem;
  box-shadow: none;
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  cursor: pointer;
  transition: background-color var(--transition-normal), border-color var(--transition-normal), color var(--transition-normal), transform var(--transition-normal);
}

.btn-primary:hover {
  background-color: rgba(255, 255, 255, 0.04);
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.12);
}

.btn-sm {
  padding: 0.55rem 1rem;
  font-size: 0.875rem;
}

.btn-arrow {
  width: 14px;
  height: 14px;
  transition: transform var(--transition-normal);
}

.btn-primary:hover .btn-arrow {
  transform: translate3d(3px, 0, 0);
}

/* Mobile Toggle */
.mobile-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--dark-border);
  border-radius: var(--radius-subtle);
  padding: 0.5rem;
  cursor: pointer;
  flex-direction: column;
  gap: 4px;
}

.hamburger-line {
  width: 20px;
  height: 2px;
  background-color: var(--dark-text-primary);
  border-radius: 2px;
}

.mobile-drawer {
  display: none;
  position: absolute;
  top: var(--header-height);
  left: 0;
  right: 0;
  background-color: rgba(9, 13, 22, 0.98);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding: 1.5rem;
}

.mobile-drawer.open {
  display: block;
}

.drawer-links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.drawer-link {
  color: var(--dark-text-secondary);
  text-decoration: none;
  font-size: 1.125rem;
  font-weight: 500;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--dark-border);
}

/* ==========================================================================
   HAND-DRAWN BUTTONS & STYLING
   ========================================================================== */
.btn-sketch-primary {
  background: #18181b;
  color: #ffffff;
  font-family: var(--font-sketch);
  font-size: 1.25rem;
  font-weight: 700;
  padding: 0.85rem 2rem;
  border: 2px solid #18181b;
  border-radius: var(--radius-sketch-box);
  box-shadow: 2px 3px 0px rgba(0, 0, 0, 0.15);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), background-color var(--transition-normal);
  transform: translate3d(0, 0, 0);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.btn-sketch-primary:hover {
  background: #000000;
  transform: translate3d(-1px, -2px, 0);
  box-shadow: 4px 6px 0px rgba(0, 0, 0, 0.2);
}

.btn-sketch-secondary {
  background: #ffffff;
  color: #18181b;
  font-family: var(--font-sketch);
  font-size: 1.25rem;
  font-weight: 700;
  padding: 0.85rem 2rem;
  border: 2px solid #18181b;
  border-radius: var(--radius-sketch-box);
  box-shadow: 2px 3px 0px rgba(0, 0, 0, 0.1);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), background-color var(--transition-normal);
  transform: translate3d(0, 0, 0);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.btn-sketch-secondary:hover {
  background: #f4f4f5;
  transform: translate3d(-1px, -2px, 0);
  box-shadow: 4px 5px 0px rgba(0, 0, 0, 0.15);
}

.sketch-btn-arrow {
  margin-left: 0.4rem;
  font-size: 1.3rem;
  display: inline-block;
  transition: transform var(--transition-normal);
}

.btn-sketch-primary:hover .sketch-btn-arrow {
  transform: translate3d(4px, 0, 0);
}

/* ==========================================================================
   PRESERVED SLEEK DARK FOOTER
   ========================================================================== */
.site-footer {
  position: relative;
  z-index: 1;
  background: radial-gradient(circle at top, rgba(2, 132, 199, 0.04) 0%, rgba(9, 13, 22, 0) 60%), var(--footer-bg);
  padding: 5rem 0 3rem 0;
  color: var(--dark-text-primary);
}

/* Custom Gradient Top Border */
.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, rgba(2, 132, 199, 0) 0%, rgba(2, 132, 199, 0.4) 25%, rgba(6, 182, 212, 0.6) 50%, rgba(239, 68, 68, 0.4) 75%, rgba(239, 68, 68, 0) 100%);
}

.footer-container {
  display: flex;
  flex-direction: column;
  gap: 3.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 3rem;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.footer-brand .brand-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.2rem;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.brand-tagline {
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--dark-text-secondary);
  max-width: 320px;
}

/* Pulse System Status */
.system-status {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: rgba(16, 185, 129, 0.05);
  border: 1px solid rgba(16, 185, 129, 0.12);
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-subtle);
  width: fit-content;
  margin-top: 0.5rem;
}

.status-dot {
  width: 7px;
  height: 7px;
  background-color: #10b981;
  border-radius: 50%;
  position: relative;
}

.status-dot::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  background-color: inherit;
  border-radius: inherit;
  top: 0;
  left: 0;
  animation: statusPulse 2s ease-out infinite;
}

.status-text {
  font-family: var(--font-mono);
  font-size: 0.725rem;
  font-weight: 500;
  color: #10b981;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

@keyframes statusPulse {
  0% { transform: scale(1); opacity: 0.8; }
  100% { transform: scale(2.8); opacity: 0; }
}

/* Columns Navigation Links */
.footer-col-title {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #64748b;
  margin-bottom: 0.25rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.footer-links a {
  text-decoration: none;
  font-size: 0.875rem;
  color: var(--dark-text-secondary);
  transition: color var(--transition-fast), transform var(--transition-fast);
  display: inline-block;
}

.footer-links a:hover {
  color: #ffffff;
}

/* Compliance Badges Redesign */
.footer-compliance {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.compliance-badge {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background-color: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--dark-border);
  padding: 0.6rem 0.95rem;
  border-radius: var(--radius-subtle);
  font-size: 0.8125rem;
  color: var(--dark-text-secondary);
  font-family: var(--font-mono);
  transition: background-color var(--transition-normal), border-color var(--transition-normal), transform var(--transition-normal);
  cursor: default;
}

.compliance-badge:hover {
  background-color: rgba(255, 255, 255, 0.04);
  border-color: rgba(255, 255, 255, 0.12);
}

.badge-icon, .btn-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  filter: invert(68%) sepia(14%) saturate(464%) hue-rotate(181deg) brightness(91%) contrast(88%);
  transition: filter var(--transition-normal);
}

.compliance-badge:hover .shield-icon {
  filter: invert(61%) sepia(80%) saturate(1478%) hue-rotate(149deg) brightness(98%) contrast(97%);
}

.compliance-badge:hover .maple-icon {
  filter: invert(37%) sepia(93%) saturate(5422%) hue-rotate(349deg) brightness(95%) contrast(98%);
}

.btn-primary:hover .btn-icon {
  filter: invert(72%) sepia(43%) saturate(2500%) hue-rotate(170deg) brightness(100%) contrast(98%);
}

/* Bottom Bar styling */
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 0.875rem;
  color: #64748b;
}

.domain-tag {
  font-family: var(--font-mono);
  color: #38bdf8;
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
}

#current-year {
  margin: 0 0.25rem;
}

/* Utilities */
.w-full { width: 100%; }
.text-center { text-align: center; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }
.mt-5 { margin-top: 2rem; }

/* Responsive */
@media (max-width: 992px) {
  .desktop-nav { display: none; }
  .mobile-toggle { display: flex; }
  
  .header-actions .btn-primary {
    display: none;
  }
  
  .footer-grid {
    grid-template-columns: 1.5fr 1fr;
    gap: 2.5rem;
  }
}

@media (max-width: 768px) {
  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}

@media (max-width: 576px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  .brand-tagline {
    max-width: 100%;
  }
}