/* ===== RESET & BASE ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: var(--font-body);
  line-height: 1.6;
  color: var(--color-warm-white);
  background-color: var(--color-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.25s ease, background-color 0.25s ease, box-shadow 0.25s ease;
}

ul, ol {
  list-style: none;
}

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

:focus-visible {
  outline: 2px solid var(--color-accent-yellow);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ===== CSS VARIABLES ===== */
:root {
  --color-primary: #0B1D3A;
  --color-accent-yellow: #FFD700;
  --color-accent-purple: #7B2D8E;
  --color-warm-white: #F5F5F5;
  --color-dark-gray: #2A2A2A;
  --color-accent-blue: #00D4FF;
  --color-soft-purple: #A55BEE;
  --color-transparent-dark: rgba(11, 29, 58, 0.8);

  --font-body: 1rem;
  --font-small: 0.875rem;
  --font-h1: 2.5rem;
  --font-h2: 1.75rem;
  --font-h3: 1.25rem;

  --max-width: 1200px;
  --header-h: 64px;
  --spacer-xs: 0.25rem;
  --spacer-sm: 0.5rem;
  --spacer-md: 1rem;
  --spacer-lg: 2rem;
  --spacer-xl: 4rem;
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4 {
  font-weight: 800;
  letter-spacing: 0.05em;
  line-height: 1.2;
}

h1 { font-size: var(--font-h1); }
h2 { font-size: var(--font-h2); }
h3 { font-size: var(--font-h3); }

/* ===== SKIP LINK ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  z-index: 1000;
  padding: 0.75rem 1.5rem;
  background: var(--color-accent-yellow);
  color: var(--color-primary);
  font-weight: 700;
  font-size: var(--font-small);
  clip: rect(1px, 1px, 1px, 1px);
  overflow: hidden;
  white-space: nowrap;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
  clip: auto;
  overflow: visible;
  white-space: normal;
  outline: none;
  box-shadow: 0 0 0 4px rgba(0, 212, 255, 0.5);
}

/* ===== CONTAINER ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* ===== HEADER ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 500;
  background: var(--color-transparent-dark);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 212, 255, 0.25);
}

.header-frame {
  position: relative;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: var(--spacer-md);
}

/* Brand */
.brand-link {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  white-space: nowrap;
}

.brand-primary {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  background: linear-gradient(135deg, var(--color-warm-white) 0%, var(--color-accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.brand-divider {
  color: var(--color-accent-purple);
  font-weight: 300;
  opacity: 0.6;
}

.brand-secondary {
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--color-accent-blue);
  opacity: 0.9;
}

/* Navigation */
.header-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-link {
  display: block;
  padding: 0.5rem 1rem;
  font-size: var(--font-small);
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--color-warm-white);
  border-radius: 4px;
  transition: color 0.25s ease, background-color 0.25s ease;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--color-accent-yellow);
  background-color: rgba(255, 215, 0, 0.08);
}

.nav-link[aria-current="page"] {
  color: var(--color-accent-yellow);
  border-bottom: 2px solid var(--color-accent-yellow);
  border-radius: 0;
  padding-bottom: calc(0.5rem - 2px);
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--spacer-md);
}

/* Toggle Button */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 5px;
  border-radius: 4px;
  transition: background-color 0.2s ease;
}

.nav-toggle:hover {
  background-color: rgba(255, 215, 0, 0.1);
}

.toggle-line {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-warm-white);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle[aria-expanded="true"] .toggle-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .toggle-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .toggle-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Header Border Decoration */
.header-border {
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, var(--color-accent-blue) 20%, var(--color-accent-purple) 50%, var(--color-accent-blue) 80%, transparent 100%);
  background-size: 200% 100%;
  animation: flowBorder 4s ease-in-out infinite;
  opacity: 0.7;
}

@keyframes flowBorder {
  0% { background-position: 0% 0%; }
  50% { background-position: 100% 0%; }
  100% { background-position: 0% 0%; }
}

/* Corner Decorations */
.header-corner {
  position: absolute;
  bottom: -12px;
  width: 12px;
  height: 12px;
  border-color: var(--color-accent-blue);
  border-style: solid;
  opacity: 0.5;
}

.header-corner-left {
  left: 0;
  border-width: 0 0 2px 2px;
}

.header-corner-right {
  right: 0;
  border-width: 0 2px 2px 0;
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.4rem;
  font-size: var(--font-small);
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 4px;
  transition: background-color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-accent-yellow);
  color: var(--color-primary);
  box-shadow: 0 0 12px rgba(255, 215, 0, 0.25);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--color-accent-blue);
  color: var(--color-primary);
  box-shadow: 0 0 20px rgba(0, 212, 255, 0.4);
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0);
}

/* ===== FOOTER ===== */
.site-footer {
  background: var(--color-primary);
  color: var(--color-warm-white);
  border-top: 1px solid rgba(0, 212, 255, 0.15);
  position: relative;
}

/* Footer Diagonal Decor */
.footer-decor {
  height: 4px;
  background: linear-gradient(135deg, transparent 30%, var(--color-accent-yellow) 50%, var(--color-accent-purple) 70%, transparent 85%);
  opacity: 0.4;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 60%);
}

.footer-body {
  padding-top: var(--spacer-xl);
  padding-bottom: var(--spacer-lg);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--spacer-lg);
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: var(--spacer-sm);
}

.footer-logo {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  background: linear-gradient(135deg, var(--color-warm-white) 0%, var(--color-accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--spacer-xs);
}

.footer-tagline {
  font-size: var(--font-small);
  color: var(--color-accent-blue);
  letter-spacing: 0.04em;
  opacity: 0.85;
}

.footer-statement {
  font-size: var(--font-small);
  color: rgba(245, 245, 245, 0.7);
  line-height: 1.7;
  max-width: 480px;
  margin-top: var(--spacer-sm);
}

.footer-heading {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--color-accent-yellow);
  margin-bottom: var(--spacer-sm);
  padding-bottom: var(--spacer-xs);
  border-bottom: 1px solid rgba(255, 215, 0, 0.2);
}

.contact-list,
.footer-link-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacer-sm);
}

.contact-item {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
  font-size: var(--font-small);
  color: rgba(245, 245, 245, 0.75);
}

.contact-label {
  font-weight: 600;
  color: var(--color-warm-white);
  white-space: nowrap;
}

.contact-link,
.contact-text {
  color: rgba(245, 245, 245, 0.7);
  transition: color 0.25s ease;
}

.contact-link:hover,
.contact-link:focus-visible {
  color: var(--color-accent-blue);
}

.footer-link {
  font-size: var(--font-small);
  color: rgba(245, 245, 245, 0.7);
  padding: 0.25rem 0;
  display: inline-block;
  transition: color 0.25s ease, padding-left 0.25s ease;
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--color-accent-yellow);
  padding-left: 4px;
}

/* Footer Bottom */
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding: var(--spacer-md) 0;
}

.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacer-sm);
  font-size: 0.8rem;
  color: rgba(245, 245, 245, 0.45);
}

.footer-icp {
  letter-spacing: 0.03em;
}

.footer-year {
  letter-spacing: 0.02em;
}

/* ===== PROGRESS BAR ===== */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 999;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent-yellow), var(--color-accent-blue));
  width: 0%;
  transition: width 0.1s linear;
  pointer-events: none;
}

@media (prefers-reduced-motion: reduce) {
  .progress-bar {
    transition: none;
  }
  html {
    scroll-behavior: auto;
  }
  .header-border {
    animation: none;
  }
}

/* ===== SECTION TITLE ===== */
.section-title {
  font-size: var(--font-h2);
  letter-spacing: 0.06em;
  background: linear-gradient(135deg, var(--color-warm-white) 0%, var(--color-accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  padding-bottom: var(--spacer-sm);
  border-bottom: 2px solid var(--color-accent-purple);
  margin-bottom: var(--spacer-lg);
}

/* ===== DATA FLOW LINE ===== */
.data-flow-line {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-accent-blue), var(--color-soft-purple), transparent);
  background-size: 200% 100%;
  animation: flowLine 3s ease-in-out infinite;
  opacity: 0.5;
  margin: var(--spacer-lg) 0;
}

@keyframes flowLine {
  0% { background-position: -100% 0%; }
  100% { background-position: 100% 0%; }
}

/* ===== GLOW TEXT ===== */
.glow-text {
  text-shadow: 0 0 12px rgba(0, 212, 255, 0.4), 0 0 30px rgba(0, 212, 255, 0.15);
}

/* ===== CARD ===== */
.card {
  background: rgba(11, 29, 58, 0.7);
  border: 1px solid rgba(0, 212, 255, 0.12);
  border-radius: 6px;
  padding: 1.5rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(0, 212, 255, 0.1);
  border-color: rgba(0, 212, 255, 0.3);
}

/* ===== BREADCRUMB ===== */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: var(--font-small);
  color: rgba(245, 245, 245, 0.5);
  padding: var(--spacer-sm) 0;
}

.breadcrumb a {
  color: rgba(245, 245, 245, 0.6);
  transition: color 0.2s ease;
}

.breadcrumb a:hover {
  color: var(--color-accent-yellow);
}

.breadcrumb .separator {
  color: var(--color-accent-purple);
  font-weight: 300;
}

.breadcrumb .current {
  color: var(--color-warm-white);
  font-weight: 500;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 992px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .footer-brand-col {
    grid-column: 1 / -1;
  }
  .footer-statement {
    max-width: 100%;
  }
  .nav-link {
    padding: 0.5rem 0.75rem;
    font-size: 0.8rem;
  }
}

@media (max-width: 768px) {
  :root {
    --header-h: 56px;
  }

  .header-inner {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .brand-secondary {
    display: none;
  }

  .brand-primary {
    font-size: 1.1rem;
  }

  /* Navigation becomes overlay */
  .header-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--color-transparent-dark);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, opacity 0.3s ease;
    opacity: 0;
    border-bottom: 1px solid rgba(0, 212, 255, 0.15);
  }

  .header-nav[data-open] {
    max-height: 80vh;
    opacity: 1;
    overflow-y: auto;
  }

  .nav-list {
    flex-direction: column;
    gap: 0;
    padding: var(--spacer-sm) 0;
  }

  .nav-link {
    padding: 0.85rem 1.5rem;
    font-size: var(--font-body);
    width: 100%;
    border-radius: 0;
    border-left: 3px solid transparent;
  }

  .nav-link:hover,
  .nav-link:focus-visible {
    background-color: rgba(255, 215, 0, 0.06);
    border-left-color: var(--color-accent-yellow);
  }

  .nav-link[aria-current="page"] {
    border-bottom: none;
    border-left: 3px solid var(--color-accent-yellow);
    background-color: rgba(255, 215, 0, 0.08);
    padding-bottom: 0.85rem;
  }

  .nav-toggle {
    display: flex;
  }

  .header-actions .btn-primary {
    display: none;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--spacer-lg);
  }

  .footer-bottom-inner {
    flex-direction: column;
    text-align: center;
  }

  .container {
    padding-left: 1rem;
    padding-right: 1rem;
  }
}

@media (max-width: 480px) {
  .brand-divider {
    display: none;
  }
  .header-corner {
    display: none;
  }
}

/* ===== REDUCED MOTION ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html {
    scroll-behavior: auto;
  }
}

/* ===== PRINT STYLES ===== */
@media print {
  .site-header {
    position: static;
    border-bottom: 1px solid #ccc;
    backdrop-filter: none;
  }
  .header-border,
  .header-corner {
    display: none;
  }
  .btn {
    display: none;
  }
  .progress-bar {
    display: none;
  }
  .site-footer {
    border-top: 1px solid #ccc;
  }
  body {
    background: #fff;
    color: #222;
  }
  .footer-decor {
    display: none;
  }
}