:root {
  --bg: #0a0a0a;
  --bg-elevated: #141414;
  --panel: #1a1a1a;
  --panel-edge: #2a2a2a;
  --steel: #8a8f98;
  --steel-bright: #c5cad3;
  --text: #e8eaed;
  --text-dim: #9aa0a8;
  --accent: #d0d4dc;
  --hook: #5c6370;
  --radius: 4px;
  --font: "Segoe UI", system-ui, -apple-system, Roboto, Helvetica, Arial, sans-serif;
  --shadow: 0 18px 40px rgba(0, 0, 0, 0.55);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  font-size: 1.05rem;
  line-height: 1.55;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--steel-bright);
  text-decoration: none;
  transition: color 0.2s ease, background-color 0.2s ease;
}

a:hover,
a:focus-visible {
  color: #fff;
}

:focus-visible {
  outline: 2px solid var(--steel-bright);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: #fff;
  color: #000;
  padding: 0.75rem 1.25rem;
  z-index: 100;
  border-radius: var(--radius);
}

.skip-link:focus {
  top: 1rem;
}

.container {
  width: min(100% - 2rem, 1100px);
  margin-inline: auto;
}

.narrow {
  width: min(100% - 2rem, 720px);
}

/* ---------- Ambient side rails ---------- */
.rail {
  display: none;
  position: fixed;
  top: 0;
  bottom: 0;
  width: 72px;
  pointer-events: none;
  z-index: 0;
  opacity: 0.35;
  background:
    repeating-linear-gradient(
      to bottom,
      transparent 0,
      transparent 28px,
      rgba(255, 255, 255, 0.04) 28px,
      rgba(255, 255, 255, 0.04) 30px
    ),
    linear-gradient(90deg, rgba(255,255,255,0.06), transparent 60%);
}

.rail-left {
  left: 0;
}

.rail-right {
  right: 0;
  transform: scaleX(-1);
}

@media (min-width: 1100px) {
  .rail {
    display: block;
  }
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(10, 10, 10, 0.88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--panel-edge);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 4.25rem;
}

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

.brand-mark {
  width: 14px;
  height: 36px;
  background: linear-gradient(180deg, var(--steel-bright), var(--steel));
  border-radius: 2px;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.15);
}

.site-header h1 {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #fff;
  line-height: 1.1;
}

.tagline {
  font-size: 0.8rem;
  color: var(--text-dim);
  letter-spacing: 0.04em;
}

.primary-nav {
  display: flex;
  gap: 0.35rem;
}

.primary-nav a {
  padding: 0.4rem 0.75rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-dim);
  border-radius: var(--radius);
}

.primary-nav a:hover,
.primary-nav a:focus-visible {
  color: #fff;
  background: var(--panel-edge);
}

/* Add nav toggle styles */
/* Hide checkbox */
.nav-toggle {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

/* Hamburger button – hidden on larger screens */
.nav-toggle-label {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  z-index: 60;
}

.nav-toggle-label span {
  display: block;
  height: 2px;
  background: var(--steel-bright, #c5cad3);
  border-radius: 1px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

/* Hamburger → X when open */
.nav-toggle:checked + .nav-toggle-label span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle:checked + .nav-toggle-label span:nth-child(2) {
  opacity: 0;
}
.nav-toggle:checked + .nav-toggle-label span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}
/* ---------- End nav toggle styles ---------- */


/* ---------- Hero ---------- */
.hero {
  position: relative;
  z-index: 1;
  padding-block: clamp(3rem, 8vw, 5.5rem);
  border-bottom: 1px solid var(--panel-edge);
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(140, 148, 160, 0.12), transparent 60%);
}

.hero-inner {
  max-width: 40rem;
}

.eyebrow {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--steel);
  margin-bottom: 0.85rem;
}

.hero h2 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.12;
  color: #fff;
  margin-bottom: 1.1rem;
}

.lead {
  font-size: 1.12rem;
  color: var(--text-dim);
  max-width: 36rem;
}

.lead em {
  color: var(--steel-bright);
  font-style: normal;
}

body {
  position: relative;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image: url("pexels-terentev.webp");
  background-size: cover;
  background-position: center center;
  background-repeat: no-repeat;
}

@media (max-width: 800px) {
  body::before {
    position: absolute;   /* not fixed */
    inset: auto;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;        /* one viewport tall, stays sharp */
    background-image: url("pexels-terentev-mobile.webp");
    background-size: cover;
    background-position: center top; /* adjust if needed */
  }
}

/* Let the image show through major surfaces */
.site-header {
  background: rgba(10, 10, 10, 0.78);
  backdrop-filter: blur(12px);
}

.hero {
  background: rgba(10, 10, 10, 0.55);
  backdrop-filter: blur(2px);
}

.panels {
  background: transparent;
}

.panel-body {
  background: rgba(16, 16, 16, 0.85);
  backdrop-filter: blur(6px);
}

.section {
  background: rgba(10, 10, 10, 0.72);
  backdrop-filter: blur(4px);
}

.section.alt {
  background: rgba(14, 14, 14, 0.8);
}

.sidebar {
  background: rgba(10, 10, 10, 0.82);
  backdrop-filter: blur(6px);
}

.site-footer {
  background: rgba(0, 0, 0, 0.88);
  backdrop-filter: blur(6px);
}


/* ---------- Hanging panels ---------- */
.panels {
  position: relative;
  z-index: 1;
  padding-block: clamp(3rem, 7vw, 5rem);
}

.panels-grid {
  display: grid;
  gap: 2rem;
  grid-template-columns: 1fr;
}

@media (min-width: 720px) {
  .panels-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2.25rem 1.75rem;
  }
}

.panel {
  position: relative;
  transform-origin: top center;
  transform: perspective(900px) rotateX(4deg);
  transition: transform 0.55s cubic-bezier(0.22, 1, 0.36, 1), box-shadow 0.4s ease;
}

.panel:hover,
.panel:focus-within {
  transform: perspective(900px) rotateX(0deg) translateY(-4px);
}

.panel-hook {
  width: 3px;
  height: 28px;
  margin: 0 auto 0;
  background: linear-gradient(180deg, var(--hook), #3a3f48);
  border-radius: 1px;
  position: relative;
}

.panel-hook::before {
  content: "";
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 16px;
  height: 16px;
  border: 3px solid var(--hook);
  border-radius: 50%;
  background: var(--bg);
}

.panel-body {
  background:
    linear-gradient(145deg, rgba(255,255,255,0.04), transparent 40%),
    var(--panel);
  border: 1px solid var(--panel-edge);
  border-radius: 2px;
  padding: 1.6rem 1.5rem 1.5rem;
  box-shadow: var(--shadow);
  /* subtle “brushed metal” lines */
  background-image:
    repeating-linear-gradient(
      90deg,
      transparent,
      transparent 3px,
      rgba(255,255,255,0.015) 3px,
      rgba(255,255,255,0.015) 4px
    ),
    linear-gradient(145deg, rgba(255,255,255,0.05), transparent 45%),
    linear-gradient(var(--panel), var(--panel));
}

.panel-body h3 {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: 0.85rem;
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--panel-edge);
}

.panel-body p {
  color: var(--text-dim);
  font-size: 0.98rem;
}

.panel-body p + p {
  margin-top: 0.75rem;
}

/* Slight alternate tilt for visual interest */
@media (min-width: 720px) {
  .panel-a { transform: perspective(900px) rotateX(4deg) rotateZ(-0.6deg); }
  .panel-b { transform: perspective(900px) rotateX(4deg) rotateZ(0.6deg); }
  .panel-c { transform: perspective(900px) rotateX(4deg) rotateZ(0.5deg); }
  .panel-d { transform: perspective(900px) rotateX(4deg) rotateZ(-0.5deg); }

  .panel-a:hover, .panel-a:focus-within,
  .panel-b:hover, .panel-b:focus-within,
  .panel-c:hover, .panel-c:focus-within,
  .panel-d:hover, .panel-d:focus-within {
    transform: perspective(900px) rotateX(0) rotateZ(0) translateY(-4px);
  }
}

/* ---------- Content sections ---------- */
.section {
  position: relative;
  z-index: 1;
  padding-block: clamp(2.75rem, 6vw, 4rem);
  border-top: 1px solid var(--panel-edge);
}

.section.alt {
  background: var(--bg-elevated);
}

.section h2 {
  font-size: clamp(1.4rem, 3vw, 1.85rem);
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: 1.25rem;
}

.prose p {
  color: var(--text-dim);
  max-width: 40rem;
}

.prose p + p {
  margin-top: 1rem;
}

.prose code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
  color: var(--steel-bright);
  background: rgba(255,255,255,0.06);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}

.prose strong {
  color: var(--text);
  font-weight: 700;
}

/* ---------- Sidebar ---------- */
.sidebar {
  position: relative;
  z-index: 1;
  background: #0f0f0f;
  border-top: 1px solid var(--panel-edge);
  padding-block: 3rem;
}

.sidebar-inner {
  display: grid;
  gap: 2.5rem;
}

@media (min-width: 700px) {
  .sidebar-inner {
    grid-template-columns: 1.3fr 1fr;
  }
}

.sidebar h3 {
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--steel);
  margin-bottom: 1rem;
}

.link-list {
  list-style: none;
}

.link-list li {
  margin-bottom: 0.65rem;
  font-size: 0.95rem;
}

.link-list a {
  color: #7ef9d6;
  font-weight: 600;
  text-decoration: underline;
}

.link-list span {
  display: block;
  font-size: 0.82rem;
  color: var(--text-dim);
  font-weight: 400;
}

/* ---------- Footer ---------- */
.site-footer {
  background: #000;
  border-top: 1px solid var(--panel-edge);
  padding-block: 1.75rem;
  font-size: 0.9rem;
  color: var(--text-dim);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  align-items: center;
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .panel,
  .panel-a,
  .panel-b,
  .panel-c,
  .panel-d {
    transition: none;
    transform: none !important;
  }
}

/* ---------- Small screens ---------- */
@media (max-width: 560px) {
  .nav-toggle-label {
    display: flex;
  }

  .primary-nav {
    position: fixed;
    top: 4.25rem; /* match header height */
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(42, 42, 42, 0.7);
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s ease, opacity 0.25s ease, visibility 0.25s;
    z-index: 55;
  }

  .nav-toggle:checked ~ .primary-nav {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .primary-nav a {
    display: block;
    padding: 0.85rem 1rem;
    color: var(--text, #e8eaed);
    font-weight: 600;
    border-radius: 4px;
  }

  .primary-nav a:hover,
  .primary-nav a:focus-visible {
    background: rgba(255, 255, 255, 0.08);
    color: #fff;
  }

  .panel-body {
    padding: 1.25rem 1.15rem;
  }
}