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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

/* ===== Variables ===== */
:root {
  --deep-navy: #0a0f1f;
  --charcoal: #111827;
  --surface-mist: #1e293b;
  --volt-green: #a3e635;
  --electric-orange: #fb923c;
  --yellow-card: #facc15;
  --data-cyan: #22d3ee;
  --red-card: #f43f5e;
  --text-high: #f8fafc;
  --text-mid: #94a3b8;
  --font-display: 'Oswald', 'DIN Condensed', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-data: 'JetBrains Mono', 'SF Mono', 'Courier New', monospace;
  --container-max: 1280px;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 40px;
  --space-6: 64px;
}

/* ===== Base ===== */
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-high);
  background-color: var(--deep-navy);
  background-image:
    linear-gradient(rgba(163, 230, 53, 0.022) 1px, transparent 1px),
    linear-gradient(90deg, rgba(163, 230, 53, 0.022) 1px, transparent 1px);
  background-size: 40px 40px;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-high);
}

h1 {
  font-size: 56px;
  letter-spacing: 0.01em;
}

h2 {
  font-size: 40px;
  letter-spacing: 0.01em;
}

h3 {
  font-size: 28px;
  letter-spacing: 0.02em;
}

h4 {
  font-size: 20px;
  letter-spacing: 0.02em;
}

p {
  color: var(--text-mid);
  margin-bottom: var(--space-3);
}

a {
  color: var(--volt-green);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

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

::selection {
  background: rgba(163, 230, 53, 0.3);
  color: var(--text-high);
}

a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--volt-green);
  outline-offset: 2px;
  border-radius: 2px;
}

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

/* ===== Skip Link ===== */
.skip-link {
  position: fixed;
  top: -48px;
  left: var(--space-3);
  z-index: 3000;
  padding: 10px 16px;
  background-color: var(--volt-green);
  color: var(--deep-navy);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  border-radius: 0 0 6px 6px;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
  text-decoration: none;
}

/* ===== Layout ===== */
.content-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.section {
  padding: var(--space-6) 0;
}

.section--alternate {
  background-color: var(--charcoal);
}

.section__header {
  margin-bottom: var(--space-5);
  max-width: 720px;
}

.section__title {
  margin-bottom: var(--space-2);
}

.section__desc {
  font-size: 16px;
  color: var(--text-mid);
  margin-bottom: 0;
}

.section-label {
  display: inline-block;
  font-family: var(--font-data);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--volt-green);
  border-left: 3px solid var(--volt-green);
  padding-left: var(--space-2);
  margin-bottom: var(--space-2);
}

/* ===== Grid ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: var(--space-4);
}

@media (max-width: 767.98px) {
  .grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .grid__span-3,
  .grid__span-4,
  .grid__span-5,
  .grid__span-6,
  .grid__span-7,
  .grid__span-8,
  .grid__span-12 {
    grid-column: span 4;
  }
}

@media (min-width: 768px) {
  .grid__span-3 { grid-column: span 3; }
  .grid__span-4 { grid-column: span 4; }
  .grid__span-5 { grid-column: span 5; }
  .grid__span-6 { grid-column: span 6; }
  .grid__span-7 { grid-column: span 7; }
  .grid__span-8 { grid-column: span 8; }
  .grid__span-12 { grid-column: span 12; }
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px 28px;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.2;
  border-radius: 4px;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  text-decoration: none;
}

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

.btn--primary {
  background-color: var(--volt-green);
  color: var(--deep-navy);
}

.btn--primary:hover {
  background-color: #b8f04a;
  color: var(--deep-navy);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(163, 230, 53, 0.5);
  color: var(--volt-green);
}

.btn--ghost:hover {
  background-color: rgba(163, 230, 53, 0.08);
  border-color: var(--volt-green);
  color: var(--volt-green);
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  font-size: 14px;
  color: var(--text-mid);
  margin-bottom: var(--space-4);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  list-style: none;
}

.breadcrumb__item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.breadcrumb__item:not(:last-child)::after {
  content: '/';
  color: var(--text-mid);
  opacity: 0.5;
}

.breadcrumb__link {
  color: var(--text-mid);
  transition: color 0.2s ease;
}

.breadcrumb__link:hover {
  color: var(--volt-green);
}

.breadcrumb__current {
  color: var(--text-high);
  font-weight: 500;
}

/* ===== Image Frame ===== */
.image-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: 4px;
  background-color: var(--surface-mist);
  background-image:
    linear-gradient(rgba(163, 230, 53, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(163, 230, 53, 0.06) 1px, transparent 1px);
  background-size: 24px 24px;
  aspect-ratio: 16 / 9;
}

.image-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.image-frame::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10, 15, 31, 0.4), rgba(10, 15, 31, 0.8));
  pointer-events: none;
}

.image-frame > img + .image-frame__no-overlay,
.image-frame:has(> img)::after {
  background: linear-gradient(135deg, rgba(10, 15, 31, 0.1), rgba(10, 15, 31, 0.5));
}

.image-frame--tilt {
  transform: rotate(-1deg);
}

.image-frame--tall {
  aspect-ratio: 3 / 4;
}

/* ===== Progress Bar ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background-color: var(--volt-green);
  box-shadow: 0 0 10px rgba(163, 230, 53, 0.45);
  z-index: 2500;
}

/* ===== Header ===== */
.site-header {
  position: relative;
  background-color: var(--deep-navy);
  border-bottom: 1px solid rgba(163, 230, 53, 0.22);
}

.site-header__inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.site-header__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) 0;
}

.site-header__brand {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
  text-decoration: none;
  min-width: 0;
}

.site-header__brand:hover {
  text-decoration: none;
}

.site-header__brand-name {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--volt-green);
  text-shadow: 0 0 20px rgba(163, 230, 53, 0.25);
  white-space: nowrap;
}

.site-header__brand-note {
  display: none;
  font-size: 13px;
  color: var(--text-mid);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

@media (min-width: 768px) {
  .site-header__brand-note {
    display: inline;
    max-width: 320px;
  }
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

.site-header__status {
  display: none;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--text-mid);
  white-space: nowrap;
}

@media (min-width: 768px) {
  .site-header__status {
    display: flex;
  }
}

.site-header__status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--volt-green);
  box-shadow: 0 0 6px rgba(163, 230, 53, 0.8);
}

.site-header__toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 36px;
  padding: 6px 8px;
  background: transparent;
  border: 1px solid rgba(148, 163, 184, 0.3);
  border-radius: 4px;
  cursor: pointer;
  transition: border-color 0.2s ease;
}

.site-header__toggle:hover {
  border-color: var(--volt-green);
}

@media (min-width: 768px) {
  .site-header__toggle {
    display: none;
  }
}

.site-header__toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--text-high);
  transition: transform 0.22s ease, opacity 0.22s ease, background-color 0.22s ease;
}

.site-header__toggle:hover .site-header__toggle-bar {
  background-color: var(--volt-green);
}

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

.site-header__toggle[aria-expanded="true"] .site-header__toggle-bar:nth-child(2) {
  opacity: 0;
}

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

.site-header__nav {
  display: none;
  border-top: 1px solid rgba(148, 163, 184, 0.1);
}

.site-header__nav[data-open] {
  display: block;
}

@media (min-width: 768px) {
  .site-header__nav {
    display: block;
    border-top: none;
  }
}

.site-header__nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  margin: 0;
  padding: var(--space-2) 0 var(--space-3);
}

@media (min-width: 768px) {
  .site-header__nav-list {
    flex-direction: row;
    gap: var(--space-5);
    padding: 0;
  }
}

.site-header__nav-item {
  margin: 0;
}

.site-header__nav-link {
  display: block;
  position: relative;
  padding: 10px 0;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 500;
  color: var(--text-high);
  text-decoration: none;
  border-bottom: 1px solid rgba(148, 163, 184, 0.08);
  transition: color 0.2s ease;
}

.site-header__nav-link:hover {
  color: var(--volt-green);
  text-decoration: none;
}

.site-header__nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--volt-green);
  transition: width 0.25s ease;
}

.site-header__nav-link:hover::after,
.site-header__nav-link[aria-current="page"]::after {
  width: 100%;
}

.site-header__nav-link[aria-current="page"] {
  color: var(--volt-green);
}

@media (min-width: 768px) {
  .site-header__nav-link {
    padding: 16px 0;
    border-bottom: none;
  }
}

/* ===== Footer ===== */
.site-footer {
  background-color: var(--charcoal);
  border-top: 1px solid rgba(163, 230, 53, 0.18);
  color: var(--text-mid);
}

.site-footer__inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.site-footer__main {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-5);
  padding: var(--space-6) 0 var(--space-5);
}

@media (min-width: 768px) {
  .site-footer__main {
    grid-template-columns: 2fr 1fr 1.5fr;
    gap: var(--space-4);
  }
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--space-2);
}

.site-footer__brand-name {
  display: block;
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--volt-green);
  text-shadow: 0 0 20px rgba(163, 230, 53, 0.2);
}

.site-footer__note {
  font-size: 14px;
  color: var(--text-mid);
  margin: 0;
  max-width: 280px;
}

.site-footer__heading {
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-high);
  margin-bottom: var(--space-3);
  padding-bottom: var(--space-2);
  border-bottom: 1px solid rgba(148, 163, 184, 0.2);
}

.site-footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.site-footer__link {
  font-size: 14px;
  color: var(--text-mid);
  text-decoration: none;
  transition: color 0.2s ease;
}

.site-footer__link:hover {
  color: var(--volt-green);
  text-decoration: none;
}

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

.site-footer__contact-line {
  font-size: 14px;
  color: var(--text-mid);
  margin: 0;
  overflow-wrap: break-word;
}

.site-footer__bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: var(--space-4) 0;
  border-top: 1px solid rgba(148, 163, 184, 0.1);
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--text-mid);
}

@media (min-width: 768px) {
  .site-footer__bottom {
    flex-direction: row;
  }
}

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

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

  .site-header__toggle[aria-expanded="true"] .site-header__toggle-bar:nth-child(2) {
    opacity: 0;
  }

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