:root {
  --bg: #0b1220;
  --bg-elev: #121a2b;
  --panel: #162033;
  --ink: #e8eef9;
  --muted: #9aabc4;
  --line: rgba(148, 180, 220, 0.16);
  --cyan: #2ee6a6;
  --cyan-dim: #1bbf88;
  --blue: #4da3ff;
  --violet: #8b7cff;
  --warn: #f0b429;
  --danger: #ff6b6b;
  --radius: 14px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --font: "IBM Plex Sans", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
  --focus: #2ee6a6;
  --max: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background:
    radial-gradient(900px 420px at 12% -8%, rgba(46, 230, 166, 0.12), transparent 55%),
    radial-gradient(800px 360px at 100% 0%, rgba(77, 163, 255, 0.14), transparent 50%),
    radial-gradient(700px 400px at 70% 100%, rgba(139, 124, 255, 0.08), transparent 45%),
    var(--bg);
  line-height: 1.65;
  min-height: 100vh;
}
a { color: var(--cyan); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: #7dffc9; }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}
img { max-width: 100%; height: auto; }
.container { width: min(var(--max), calc(100% - 2rem)); margin: 0 auto; }
.narrow { width: min(760px, 100%); }
.visually-hidden {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: 0.75rem; top: -3rem; z-index: 1000;
  background: var(--cyan); color: #042016; font-weight: 700;
  padding: 0.55rem 0.9rem; border-radius: 0 0 8px 8px; text-decoration: none;
}
.skip-link:focus { top: 0; }

.site-promo {
  background: linear-gradient(90deg, rgba(46,230,166,0.12), rgba(77,163,255,0.10));
  border-bottom: 1px solid var(--line);
  font-size: 0.92rem;
}
.site-promo-inner {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1rem;
  padding: 0.55rem 0; color: var(--muted);
}
.site-promo a { font-weight: 600; }

.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(11, 18, 32, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: 0.75rem 1rem; padding: 0.85rem 0;
}
.brand {
  color: var(--ink); text-decoration: none; display: flex; align-items: center; gap: 0.65rem;
  min-width: min(100%, 15rem);
}
.brand-mark {
  display: inline-grid; place-items: center;
  width: 2.4rem; height: 2.4rem; border-radius: 10px;
  background: linear-gradient(135deg, var(--cyan), var(--blue));
  color: #042016; font-family: var(--mono); font-weight: 700; font-size: 1.05rem;
  box-shadow: 0 0 0 1px rgba(46,230,166,0.35), 0 8px 24px rgba(46,230,166,0.18);
}
.brand-title { display: block; font-weight: 700; letter-spacing: -0.02em; }
.brand-tagline { display: block; font-size: 0.78rem; color: var(--muted); max-width: 22rem; line-height: 1.3; }
.nav { display: flex; flex-wrap: wrap; gap: 0.35rem 0.85rem; }
.nav a { color: var(--ink); text-decoration: none; font-weight: 500; font-size: 0.95rem; opacity: 0.9; }
.nav a:hover { color: var(--cyan); opacity: 1; }
.nav-toggle {
  display: none; background: var(--panel); color: var(--ink); border: 1px solid var(--line);
  border-radius: 8px; padding: 0.45rem 0.75rem; font: inherit; cursor: pointer;
}
.search-form { display: flex; gap: 0.35rem; }
.search-form input, .search-form-lg input {
  background: var(--panel); border: 1px solid var(--line); color: var(--ink);
  border-radius: 999px; padding: 0.45rem 0.85rem; min-width: 12rem; font: inherit;
}
.search-form button, .search-form-lg button {
  background: var(--cyan); color: #042016; border: 0; border-radius: 999px;
  padding: 0.45rem 0.9rem; font-weight: 700; cursor: pointer; font: inherit;
}
.search-form-lg { margin: 1rem 0 1.5rem; max-width: 36rem; }

.hero { padding: 2.5rem 0 1rem; }
.hero-card {
  display: grid; grid-template-columns: 1.5fr 0.9fr; gap: 1.5rem; align-items: stretch;
  background: linear-gradient(160deg, rgba(22,32,51,0.95), rgba(18,26,43,0.9));
  border: 1px solid var(--line); border-radius: calc(var(--radius) + 4px);
  padding: clamp(1.25rem, 3vw, 2rem); box-shadow: var(--shadow);
}
.hero h1 {
  margin: 0.35rem 0 0.75rem; font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.15; letter-spacing: -0.03em;
}
.lead { font-size: 1.08rem; color: var(--muted); max-width: 48rem; }
.eyebrow {
  margin: 0; font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--cyan);
}
.stats { display: grid; grid-template-columns: 1fr; gap: 0.65rem; }
.stat {
  background: rgba(11,18,32,0.55); border: 1px solid var(--line); border-radius: 12px;
  padding: 0.9rem 1rem; display: flex; flex-direction: column;
}
.stat strong { font-size: 1.6rem; font-family: var(--mono); color: var(--cyan); line-height: 1.1; }
.stat span { color: var(--muted); font-size: 0.9rem; }

.section { padding: 1.75rem 0; }
.section-head { margin-bottom: 1rem; }
.page-title {
  margin: 0 0 0.5rem; font-size: clamp(1.6rem, 3vw, 2.1rem);
  letter-spacing: -0.02em;
}
.grid-2 { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 1.1rem; }
.card {
  background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.15rem 1.25rem; box-shadow: 0 8px 24px rgba(0,0,0,0.18);
}
.card-compact { padding: 1rem; }
.card h2, .card h3 { margin-top: 0; }

.btn-row { display: flex; flex-wrap: wrap; gap: 0.55rem; margin-top: 1rem; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--cyan), var(--cyan-dim));
  color: #042016; font-weight: 700; text-decoration: none; border: 0;
  border-radius: 999px; padding: 0.65rem 1.1rem; cursor: pointer; font: inherit;
}
.btn:hover { color: #02140e; filter: brightness(1.05); }
.btn-secondary {
  background: transparent; color: var(--ink); border: 1px solid var(--line);
}
.btn-secondary:hover { border-color: var(--cyan); color: var(--cyan); }
.btn-ghost {
  background: transparent; color: var(--muted); border: 1px dashed var(--line);
}
.btn-danger { background: var(--danger); color: #1a0505; }

.pillar-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.85rem;
}
.pillar-card {
  display: block; text-decoration: none; color: inherit;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.1rem; transition: transform .15s ease, border-color .15s ease;
}
.pillar-card:hover { transform: translateY(-2px); border-color: rgba(46,230,166,0.45); color: inherit; }
.pillar-icon { font-size: 1.5rem; display: block; margin-bottom: 0.4rem; }
.pillar-card h3 { margin: 0 0 0.35rem; font-size: 1.05rem; }
.pillar-card p { margin: 0; color: var(--muted); font-size: 0.92rem; }

.list-plain { list-style: none; margin: 0; padding: 0; }
.list-plain li { padding: 0.7rem 0; border-bottom: 1px solid var(--line); }
.list-plain li:last-child { border-bottom: 0; }
.post-list .excerpt { margin: 0.25rem 0 0; color: var(--muted); font-size: 0.95rem; }
.meta { color: var(--muted); font-size: 0.9rem; }
.badge {
  display: inline-block; font-family: var(--mono); font-size: 0.72rem;
  padding: 0.12rem 0.45rem; border-radius: 999px;
  background: rgba(46,230,166,0.14); color: var(--cyan); border: 1px solid rgba(46,230,166,0.28);
  margin-right: 0.25rem;
}
.badge-soft {
  background: rgba(77,163,255,0.12); color: var(--blue); border-color: rgba(77,163,255,0.28);
}

.lead-card {
  display: grid; grid-template-columns: 1.2fr 1fr; gap: 1.25rem; align-items: center;
  background: linear-gradient(135deg, rgba(46,230,166,0.10), rgba(77,163,255,0.10));
  border: 1px solid rgba(46,230,166,0.28); border-radius: var(--radius); padding: 1.25rem 1.4rem;
}
.lead-form { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.lead-form input[type=email] {
  flex: 1 1 12rem; background: var(--bg); border: 1px solid var(--line); color: var(--ink);
  border-radius: 999px; padding: 0.65rem 0.95rem; font: inherit;
}

.project-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 0.9rem;
}
.project-card {
  display: block; text-decoration: none; color: inherit;
  background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.1rem; transition: border-color .15s ease, transform .15s ease;
}
.project-card:hover { border-color: rgba(77,163,255,0.45); transform: translateY(-2px); color: inherit; }
.project-card h2 { margin: 0.4rem 0; font-size: 1.1rem; }
.project-card p { margin: 0; color: var(--muted); font-size: 0.92rem; }
.visual-card {
  position: relative;
  overflow: hidden;
  min-height: 11rem;
  background:
    linear-gradient(145deg, rgba(46,230,166,0.08), transparent 45%),
    var(--bg-elev);
}
.visual-card.hw-esp32 { background: linear-gradient(145deg, rgba(46,230,166,0.14), transparent 50%), var(--bg-elev); }
.visual-card.hw-pi { background: linear-gradient(145deg, rgba(77,163,255,0.14), transparent 50%), var(--bg-elev); }
.visual-card.hw-3d-printer, .visual-card.hw-3d-printing { background: linear-gradient(145deg, rgba(139,124,255,0.14), transparent 50%), var(--bg-elev); }
.visual-card.hw-ai { background: linear-gradient(145deg, rgba(240,180,41,0.12), transparent 50%), var(--bg-elev); }
.visual-card.hw-cnc { background: linear-gradient(145deg, rgba(255,107,107,0.12), transparent 50%), var(--bg-elev); }
.visual-card-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 0.5rem; }
.hw-badge {
  display: inline-grid; place-items: center;
  min-width: 2.5rem; height: 2.5rem; padding: 0 0.4rem;
  border-radius: 10px; font-family: var(--mono); font-weight: 700; font-size: 0.8rem;
  background: rgba(46,230,166,0.12); color: var(--cyan); border: 1px solid rgba(46,230,166,0.28);
}
.card-cta { display: inline-block; margin-top: 0.65rem; color: var(--cyan); font-weight: 600; }
.author-box {
  display: grid; grid-template-columns: 3rem 1fr; gap: 0.85rem; align-items: start;
  margin: 1rem 0 1.25rem; padding: 0.9rem 1rem;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
}
.author-mark {
  display: grid; place-items: center; width: 3rem; height: 3rem; border-radius: 10px;
  background: linear-gradient(135deg, var(--cyan), var(--blue)); color: #042016;
  font-family: var(--mono); font-weight: 700;
}
.author-name { margin: 0.1rem 0 0.25rem; font-weight: 700; }
.author-name a { color: inherit; text-decoration: none; }
.author-name a:hover { color: var(--cyan); }
.project-rail { margin: 0 0 1.25rem; }
.project-rail-list {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
  gap: 0.35rem; margin: 0.5rem 0 0.75rem; padding: 0; list-style: none;
}
.project-rail-list li {
  font-size: 0.88rem; color: var(--muted);
  padding: 0.35rem 0.55rem; border: 1px dashed var(--line); border-radius: 8px;
}
.in-body-cta { margin: 1.5rem 0; border-color: rgba(46,230,166,0.3); }
.related-block { margin: 1.75rem 0; }
.related-block h2 { margin-bottom: 0.5rem; }
.comments-block { margin-top: 1.5rem; }
.comment-list { margin: 1rem 0; }
.comment-item { padding: 0.75rem 0; border-bottom: 1px solid var(--line); }
.comment-form label, .contact-form label {
  display: flex; flex-direction: column; gap: 0.3rem; margin-bottom: 0.75rem; color: var(--muted);
}
.comment-form input, .comment-form textarea,
.contact-form input, .contact-form textarea {
  background: var(--panel); border: 1px solid var(--line); color: var(--ink);
  border-radius: 10px; padding: 0.55rem 0.7rem; font: inherit;
}
.hp-field { position: absolute !important; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
.crumbs { margin-bottom: 0.75rem; }
.crumbs a { color: var(--muted); text-decoration: none; }
.crumbs a:hover { color: var(--cyan); }
.article-dates time { white-space: nowrap; }
.project-diagram {
  margin: 1.25rem 0 1.5rem;
  padding: 0.75rem;
  background: rgba(7, 12, 22, 0.65);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.project-diagram img {
  display: block;
  width: 100%;
  height: auto;
  border: 0;
  border-radius: 8px;
}
.project-diagram figcaption {
  margin-top: 0.55rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.filters { display: flex; flex-wrap: wrap; gap: 0.75rem; align-items: end; }
.filters label { display: flex; flex-direction: column; gap: 0.25rem; font-size: 0.9rem; color: var(--muted); }
.filters select, .admin-form input, .admin-form textarea, .admin-form select,
.contact-form input, .contact-form textarea {
  background: var(--panel); border: 1px solid var(--line); color: var(--ink);
  border-radius: 10px; padding: 0.55rem 0.7rem; font: inherit;
}
.chip-row { display: flex; flex-wrap: wrap; gap: 0.45rem; }
.chip {
  display: inline-flex; align-items: center; gap: 0.35rem;
  background: var(--panel); border: 1px solid var(--line); border-radius: 999px;
  padding: 0.3rem 0.7rem; color: var(--ink); text-decoration: none; font-size: 0.88rem;
}
.chip span { font-family: var(--mono); color: var(--muted); font-size: 0.8rem; }
.chip:hover, .chip.is-active { border-color: var(--cyan); color: var(--cyan); }

.notice {
  border-radius: 10px; padding: 0.75rem 0.95rem; margin: 0 0 1rem;
  border: 1px solid var(--line); background: var(--panel);
}
.notice-archive { border-color: rgba(240,180,41,0.35); background: rgba(240,180,41,0.08); }
.notice-success { border-color: rgba(46,230,166,0.35); background: rgba(46,230,166,0.08); }
.notice-error { border-color: rgba(255,107,107,0.4); background: rgba(255,107,107,0.08); }

.prose { font-size: 1.04rem; }
.prose h2, .prose h3 { margin-top: 1.6rem; letter-spacing: -0.02em; }
.prose pre, .prose code { font-family: var(--mono); }
.prose pre {
  background: #070c16; border: 1px solid var(--line); border-radius: 10px;
  padding: 0.9rem 1rem; overflow-x: auto; font-size: 0.9rem;
}
.prose code {
  background: rgba(77,163,255,0.1); padding: 0.1rem 0.35rem; border-radius: 5px; font-size: 0.92em;
}
.prose pre code { background: transparent; padding: 0; }
.prose img { border-radius: 10px; border: 1px solid var(--line); }
.prose blockquote {
  margin: 1rem 0; padding: 0.5rem 1rem; border-left: 3px solid var(--cyan);
  color: var(--muted); background: rgba(46,230,166,0.05);
}
.article-header { margin-bottom: 1.25rem; }
.article-footer { margin-top: 2rem; }
.pagination {
  display: flex; gap: 1rem; align-items: center; justify-content: center;
  margin-top: 1.5rem; color: var(--muted);
}

.site-footer {
  margin-top: 3rem; border-top: 1px solid var(--line);
  background: rgba(7, 12, 22, 0.7); padding: 2rem 0 1.25rem;
}
.footer-grid {
  display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 1.25rem;
}
.footer-grid-5 {
  grid-template-columns: 1.3fr repeat(4, 1fr);
}
.book-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.9rem;
}
.book-grid-lg { grid-template-columns: 1fr; }
.book-card {
  display: block; text-decoration: none; color: inherit;
  background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.15rem; transition: border-color .15s ease, transform .15s ease;
}
.book-card:hover { border-color: rgba(139,124,255,0.5); transform: translateY(-2px); color: inherit; }
.book-card h3, .book-card h2 { margin: 0.25rem 0 0.5rem; }
.book-card h3 a { color: inherit; text-decoration: none; }
.book-card h3 a:hover { color: var(--cyan); }
.book-card p { margin: 0 0 0.5rem; color: var(--muted); font-size: 0.95rem; }
.book-card-lg { padding: 1.35rem 1.5rem; }
.book-card-cover {
  display: grid; grid-template-columns: 100px 1fr; gap: 1rem; align-items: start;
}
.book-cover-link img, .series-cover img, .title-card img {
  display: block; width: 100%; height: auto; border-radius: 6px;
  border: 1px solid var(--line); background: #070c16;
  box-shadow: 0 8px 20px rgba(0,0,0,0.35);
}
.book-cover-link { display: block; max-width: 100px; }
.books-group { margin-bottom: 2rem; }
.books-group-title {
  font-family: var(--mono); font-size: 0.85rem; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--cyan); margin: 0 0 0.85rem;
}
.series-block { margin-bottom: 1rem; }
.series-head {
  display: grid; grid-template-columns: 140px 1fr; gap: 1.25rem; align-items: start;
}
.series-cover { display: block; max-width: 140px; }
.titles-heading {
  margin: 1.25rem 0 0.65rem; font-size: 0.95rem; color: var(--muted); font-weight: 600;
}
.title-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 0.75rem;
}
.title-grid-compact { grid-template-columns: 1fr; }
.title-card {
  display: grid; grid-template-columns: 72px 1fr; gap: 0.75rem; align-items: center;
  text-decoration: none; color: inherit;
  background: rgba(11,18,32,0.45); border: 1px solid var(--line); border-radius: 12px;
  padding: 0.65rem 0.75rem; transition: border-color .15s ease;
}
.title-card:hover { border-color: rgba(139,124,255,0.5); color: inherit; }
.title-card img { max-width: 72px; }
.title-card-body { display: flex; flex-direction: column; gap: 0.2rem; }
.title-card-body strong { font-size: 0.92rem; line-height: 1.35; }
.network-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 0.9rem;
}
.network-card {
  display: block; text-decoration: none; color: inherit;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.15rem; transition: border-color .15s ease, transform .15s ease;
}
.network-card:hover { border-color: rgba(77,163,255,0.5); transform: translateY(-2px); color: inherit; }
.network-card.is-feature { border-color: rgba(46,230,166,0.28); background: linear-gradient(160deg, rgba(46,230,166,0.08), var(--panel)); }
.network-card h2 { margin: 0 0 0.4rem; font-size: 1.1rem; }
.network-card p { margin: 0 0 0.5rem; color: var(--muted); font-size: 0.92rem; }
.network-mini li { padding: 0.55rem 0; }
.pillar-icon {
  display: inline-grid; place-items: center;
  min-width: 2.4rem; height: 2.4rem; padding: 0 0.45rem;
  border-radius: 8px; font-family: var(--mono); font-size: 0.85rem; font-weight: 700;
  background: rgba(46,230,166,0.12); color: var(--cyan); border: 1px solid rgba(46,230,166,0.28);
  margin-bottom: 0.55rem;
}
.footer-heading { font-size: 0.95rem; margin: 0 0 0.55rem; color: var(--cyan); }
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer li { margin: 0.3rem 0; }
.site-footer a { color: var(--muted); text-decoration: none; }
.site-footer a:hover { color: var(--cyan); }
.site-footer p { color: var(--muted); }
.footer-bottom { margin-top: 1.5rem; padding-top: 1rem; border-top: 1px solid var(--line); font-size: 0.88rem; }

@media (max-width: 1100px) {
  .footer-grid-5 { grid-template-columns: 1fr 1fr 1fr; }
  .book-grid { grid-template-columns: 1fr; }
}
@media (max-width: 900px) {
  .hero-card, .grid-2, .lead-card, .footer-grid, .pillar-grid { grid-template-columns: 1fr; }
  .footer-grid-5 { grid-template-columns: 1fr 1fr; }
  .pillar-grid { grid-template-columns: 1fr 1fr; }
  .book-card-cover, .series-head { grid-template-columns: 90px 1fr; }
  .nav-toggle { display: inline-flex; }
  .nav { display: none; width: 100%; flex-direction: column; }
  .nav.is-open { display: flex; }
  .brand-tagline { display: none; }
  .search-form input { min-width: 0; width: 100%; }
}
@media (max-width: 560px) {
  .pillar-grid, .footer-grid-5 { grid-template-columns: 1fr; }
  .book-card-cover, .series-head { grid-template-columns: 1fr; }
  .book-cover-link, .series-cover { max-width: 120px; }
}