/* ==========================================================================
   Boltmoa hub — spec-sheet industrial design
   Pure static · self-hosted font only · mobile-first · dark/light
   ========================================================================== */

@font-face {
  font-family: "Pretendard";
  src: url("fonts/Pretendard-sub.woff2") format("woff2-variations");
  font-weight: 45 920;
  font-style: normal;
  font-display: swap;
}

:root {
  --paper: #f5f4f0;          /* warm drafting paper */
  --paper-raise: #fdfdfb;
  --ink: #17181a;
  --ink-soft: #43454a;
  --muted: #64686f;
  --hair: #dcdad3;           /* hairline rules */
  --hair-strong: #b9b6ac;
  --accent: #e8590c;         /* torque orange */
  --accent-ink: #c74a08;
  --panel: #1b1c1f;          /* lens dark panel */
  --panel-ink: #edebe6;
  --panel-muted: #a3a49f;
  --panel-hair: #3a3b3f;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #131417;
    --paper-raise: #1a1b1f;
    --ink: #eceae5;
    --ink-soft: #c9c7c1;
    --muted: #8f929a;
    --hair: #2b2d32;
    --hair-strong: #45484f;
    --accent: #ff7a33;
    --accent-ink: #ff8a4d;
    --panel: #0d0e10;
    --panel-ink: #eceae5;
    --panel-muted: #93958f;
    --panel-hair: #33353a;
  }
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 4.5rem;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}

body {
  font-family: "Pretendard", -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo",
    "Segoe UI", "Malgun Gothic", "Noto Sans KR", sans-serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.65;
  word-break: keep-all;
  font-feature-settings: "tnum";
}

.shell {
  max-width: 66rem;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* mono spec voice */
.eyebrow, .sec-no, .idx, .spec, .badge, .spec-strip, .dim-label,
.title-block dt, .footer-links {
  font-family: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas,
    "Liberation Mono", monospace;
}

/* --- a11y ------------------------------------------------------------ */

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--ink);
  color: var(--paper);
  padding: 0.6rem 1rem;
  z-index: 99;
}
.skip-link:focus { left: 0; }

a:focus-visible, .btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* --- header ----------------------------------------------------------- */

.site-head {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--hair);
}

.site-head-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 3.5rem;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 800;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.wordmark .mark { color: var(--ink); }

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  font-size: 0.9rem;
}

.site-nav a {
  color: var(--ink-soft);
  text-decoration: none;
  font-weight: 500;
}

.site-nav a:hover { color: var(--accent-ink); }

.site-nav .nav-store {
  color: var(--ink);
  font-weight: 700;
  border: 1px solid var(--hair-strong);
  padding: 0.32rem 0.85rem;
  border-radius: 2px;
}

.site-nav .nav-store:hover {
  border-color: var(--accent);
  color: var(--accent-ink);
}

/* 모바일: 링크 3개는 숨기고 스토어 버튼만 */
.site-nav a:not(.nav-store) { display: none; }

@media (min-width: 46rem) {
  .site-nav a:not(.nav-store) { display: inline; }
}

/* --- hero ------------------------------------------------------------- */

.hero {
  position: relative;
  border-bottom: 1px solid var(--hair);
  /* graph paper */
  background-image:
    linear-gradient(var(--hair) 1px, transparent 1px),
    linear-gradient(90deg, var(--hair) 1px, transparent 1px);
  background-size: 56px 56px;
  background-position: 28px 24px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  padding-top: 4.25rem;
  padding-bottom: 3.5rem;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  color: var(--ink-soft);
}

.eyebrow .tick {
  width: 1.6rem;
  height: 1px;
  background: var(--accent);
  display: inline-block;
}

h1 {
  margin-top: 1.1rem;
  font-size: clamp(2.9rem, 9.5vw, 5rem);
  font-weight: 850;
  letter-spacing: -0.045em;
  line-height: 1.08;
}

.accent-dot { color: var(--accent); }

.hero-sub {
  margin-top: 1.4rem;
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 30rem;
}

.cta-group {
  margin-top: 2.2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

/* --- buttons ---------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.4rem;
  padding: 0.82rem 1.25rem;
  border-radius: 2px;
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  text-decoration: none;
  border: 1px solid transparent;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.btn-arrow {
  font-weight: 400;
  transition: transform 0.15s ease;
}

.btn:hover .btn-arrow { transform: translateX(3px); }

.btn-primary {
  background: var(--ink);
  color: var(--paper);
}

.btn-primary:hover { background: var(--accent-ink); color: #fff; }

.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--hair-strong);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent-ink);
}

.btn-invert {
  background: var(--panel-ink);
  color: var(--panel);
}

.btn.is-disabled {
  background: transparent;
  color: var(--panel-muted);
  border: 1px dashed var(--panel-hair);
  cursor: not-allowed;
  pointer-events: none;
}

/* --- hero drawing ------------------------------------------------------ */

.hero-draft {
  display: none;
  color: var(--ink);
}

.bolt-drawing { width: 100%; height: auto; display: block; }

.bolt-drawing .hair {
  fill: none;
  stroke: currentColor;
  stroke-width: 1;
  opacity: 0.55;
}

.bolt-drawing .hair.strong { opacity: 0.9; stroke-width: 1.4; }
.bolt-drawing .hair.faint  { opacity: 0.28; }

.bolt-drawing .dot { fill: var(--accent); }

.bolt-drawing .dim {
  fill: none;
  stroke: var(--accent);
  stroke-width: 1;
  opacity: 0.85;
}

.bolt-drawing .dim-label {
  fill: var(--accent-ink);
  font-size: 13px;
  letter-spacing: 0.06em;
}

@media (min-width: 46rem) {
  .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: center;
    gap: 3rem;
    padding-top: 5.5rem;
    padding-bottom: 4.5rem;
  }
  .hero-draft { display: block; }
}

/* --- spec strip --------------------------------------------------------- */

.spec-strip {
  border-top: 1px solid var(--hair);
  background: var(--paper-raise);
}

.spec-strip-inner {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  padding-top: 0.72rem;
  padding-bottom: 0.72rem;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, #000 88%, transparent);
  mask-image: linear-gradient(90deg, #000 88%, transparent);
}

.spec-strip i {
  font-style: normal;
  color: var(--hair-strong);
}

/* --- section head ------------------------------------------------------- */

section { scroll-margin-top: 4rem; }

.sec-head {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  flex-wrap: wrap;
}

.sec-no {
  font-size: 0.8rem;
  color: var(--accent-ink);
  letter-spacing: 0.08em;
}

h2 {
  font-size: clamp(1.55rem, 4vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
}

.sec-sub {
  flex-basis: 100%;
  margin-top: 0.4rem;
  color: var(--muted);
}

/* --- items / catalog ----------------------------------------------------- */

.items { padding: 4.5rem 0 5rem; }

.catalog {
  list-style: none;
  margin-top: 2.2rem;
  border-top: 1px solid var(--hair-strong);
}

.catalog li {
  display: flex;
  align-items: baseline;
  gap: 1.1rem;
  padding: 0.95rem 0.25rem;
  border-bottom: 1px solid var(--hair);
}

.catalog .idx {
  font-size: 0.78rem;
  color: var(--muted);
  min-width: 1.6rem;
}

.catalog .name {
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: -0.02em;
}

.catalog .spec {
  margin-left: auto;
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-align: right;
}

.catalog li:hover .idx { color: var(--accent-ink); }

@media (min-width: 46rem) {
  .catalog {
    column-count: 2;
    column-gap: 4rem;
    border-top: 0;
  }
  .catalog li {
    break-inside: avoid;
    padding: 1.05rem 0.25rem;
  }
  .catalog li:nth-child(1),
  .catalog li:nth-child(6) { border-top: 1px solid var(--hair-strong); }
}

/* --- lens panel ----------------------------------------------------------- */

.lens { padding-bottom: 5rem; }

.lens-panel {
  position: relative;
  background: var(--panel);
  color: var(--panel-ink);
  padding: clamp(2.2rem, 6vw, 3.5rem) clamp(1.4rem, 5vw, 3.5rem) clamp(2.4rem, 6vw, 3.6rem);
  border-radius: 2px;
}

/* viewfinder corners */
.vf {
  position: absolute;
  width: 1.15rem;
  height: 1.15rem;
  border: 0 solid var(--accent);
  opacity: 0.9;
}
.vf-tl { top: 0.8rem; left: 0.8rem; border-top-width: 2px; border-left-width: 2px; }
.vf-tr { top: 0.8rem; right: 0.8rem; border-top-width: 2px; border-right-width: 2px; }
.vf-bl { bottom: 0.8rem; left: 0.8rem; border-bottom-width: 2px; border-left-width: 2px; }
.vf-br { bottom: 0.8rem; right: 0.8rem; border-bottom-width: 2px; border-right-width: 2px; }

.sec-head-invert h2 { color: var(--panel-ink); }

.badge {
  display: inline-block;
  padding: 0.18rem 0.7rem;
  border: 1px solid var(--panel-hair);
  border-radius: 999px;
  color: var(--panel-muted);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
}

/* [hidden] must win over .badge display (QA B-1) */
.badge[hidden] { display: none; }

.lens-slogan {
  margin-top: 1.8rem;
  font-size: clamp(1.5rem, 4.6vw, 2.3rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.25;
}

.lens-desc {
  margin-top: 1.1rem;
  color: var(--panel-muted);
  max-width: 34rem;
}

.lens-cta { margin-top: 2rem; }

/* --- contact ---------------------------------------------------------------- */

.contact {
  border-top: 1px solid var(--hair);
  padding: 4.5rem 0 5rem;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.6rem;
}

.contact-body { max-width: 34rem; }

.contact-body strong { font-weight: 800; }

.contact-tel {
  margin-top: 0.9rem;
  color: var(--muted);
}

.contact-tel a {
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
  border-bottom: 1px solid var(--hair-strong);
}

.contact-tel a:hover { color: var(--accent-ink); border-color: var(--accent); }

.contact-cta { margin-top: 1.8rem; }

@media (min-width: 46rem) {
  .contact-grid { grid-template-columns: minmax(0, 4fr) minmax(0, 7fr); }
}

/* --- footer · drawing title block --------------------------------------------- */

.footer {
  border-top: 1px solid var(--hair-strong);
  padding: 3rem 0 3.5rem;
  font-size: 0.85rem;
}

.title-block {
  display: grid;
  grid-template-columns: 1fr;
  border: 1px solid var(--hair-strong);
  background: var(--paper-raise);
}

.tb-cell {
  padding: 0.9rem 1.1rem;
  border-bottom: 1px solid var(--hair);
}

.tb-cell:last-child { border-bottom: 0; }

.tb-brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
}

.tb-brand .mark { color: var(--ink); flex: none; }

.tb-name {
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: -0.02em;
}

.tb-name span {
  font-weight: 500;
  color: var(--muted);
  font-size: 0.8rem;
  margin-left: 0.3rem;
}

.title-block dt {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--muted);
  text-transform: uppercase;
}

.title-block dd {
  margin-top: 0.25rem;
  color: var(--ink-soft);
  line-height: 1.5;
}

.title-block dd a {
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--hair-strong);
}

.title-block dd a:hover { color: var(--accent-ink); border-color: var(--accent); }

@media (min-width: 46rem) {
  .title-block {
    grid-template-columns: repeat(3, 1fr);
  }
  .tb-cell {
    border-bottom: 0;
    border-right: 1px solid var(--hair);
  }
  .tb-cell:nth-child(3n) { border-right: 0; }
  .tb-cell:nth-child(-n+3) { border-bottom: 1px solid var(--hair); }
  .tb-wide { grid-column: span 2; }
}

.footer-links {
  margin-top: 1.4rem;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

.footer-links a { color: var(--ink-soft); text-decoration: none; }
.footer-links a:hover { color: var(--accent-ink); }
.link-disabled { color: var(--muted); }

/* --- line breaks -------------------------------------------------------------- */

.br-desk { display: none; }
.br-mobile { display: inline; }

@media (min-width: 46rem) {
  .br-desk { display: inline; }
  .br-mobile { display: none; }
}