/* ========================================================================
   常盤設備工事 — 共通スタイル
   重厚クラシカル建築誌風 / Deep Navy × Paper × Brass
   ======================================================================== */

:root {
  --navy: #0A1F3D;
  --navy-deep: #061328;
  --navy-soft: #142A4D;
  --accent: #C9A96E;          /* brass */
  --accent-soft: #E5D2A8;
  --paper: #F5F2EC;
  --paper-deep: #ECE7DD;
  --ink: #061328;
  --line: rgba(10, 31, 61, 0.14);
  --line-light: rgba(10, 31, 61, 0.08);

  --serif: "Shippori Mincho", "Noto Serif JP", "Hiragino Mincho ProN", "Yu Mincho", serif;
  --sans:  "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--serif);
  background: var(--paper);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }

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

/* selection */
::selection { background: var(--navy); color: var(--paper); }

/* utility text */
.eyebrow {
  font-family: var(--sans);
  font-size: 11px;
  letter-spacing: 0.4em;
  text-transform: uppercase;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: var(--navy);
  opacity: 0.7;
}
.eyebrow::before {
  content: "";
  width: 32px; height: 1px;
  background: var(--accent);
  flex: 0 0 auto;
}

.eyebrow.on-dark { color: var(--paper); opacity: 0.7; }

/* page wrapper */
.page {
  min-height: 100vh;
  background: var(--paper);
  color: var(--ink);
}

/* HEADER ================================================================ */

.site-header {
  position: sticky; top: 0; z-index: 50;
  padding: 20px 48px;
  display: flex; align-items: center; justify-content: space-between;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background .35s ease, backdrop-filter .35s ease, border-color .35s ease, padding .35s ease;
}
.site-header.scrolled {
  background: rgba(245, 242, 236, 0.92);
  backdrop-filter: blur(12px) saturate(1.2);
  -webkit-backdrop-filter: blur(12px) saturate(1.2);
  border-bottom-color: var(--line);
  padding: 14px 48px;
}
.site-header.on-dark { color: var(--paper); }
.site-header.on-dark .brand-text { color: var(--paper); }
.site-header.on-dark .brand-en { color: var(--paper); }
.site-header.on-dark .nav-link { color: var(--paper); }
.site-header.on-dark .nav-cta {
  background: var(--paper); color: var(--navy-deep);
}

.brand {
  display: flex; align-items: center; gap: 14px;
  text-decoration: none;
}
.brand-mark {
  width: 44px; height: 44px;
  background: var(--navy);
  display: flex; align-items: center; justify-content: center;
  color: var(--paper);
  font-family: var(--serif);
  font-size: 24px; font-weight: 600;
  letter-spacing: -0.04em;
  position: relative;
  flex: 0 0 auto;
}
.brand-mark::after {
  content: "";
  position: absolute; inset: 4px;
  border: 1px solid rgba(245, 242, 236, 0.25);
  pointer-events: none;
}
.brand-text {
  font-family: var(--serif);
  font-size: 16px; font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--navy);
  line-height: 1.2;
}
.brand-en {
  font-family: var(--sans);
  font-size: 9px; letter-spacing: 0.32em;
  color: var(--navy);
  opacity: 0.55;
  margin-top: 4px;
  text-transform: uppercase;
}

.nav {
  display: flex; align-items: center; gap: 32px;
  font-family: var(--sans);
}
.nav-link {
  color: var(--navy);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.05em;
  position: relative;
  padding: 6px 0;
}
.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform .3s cubic-bezier(.7,0,.2,1);
}
.nav-link:hover::after,
.nav-link.active::after {
  transform: scaleX(1);
  transform-origin: left;
}
.nav-link.active {
  color: var(--accent);
}

.nav-cta {
  background: var(--navy);
  color: var(--paper);
  padding: 12px 22px;
  text-decoration: none;
  letter-spacing: 0.12em;
  font-size: 11px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  transition: background .2s, transform .2s;
}
.nav-cta:hover {
  background: var(--navy-deep);
  transform: translateX(-2px);
}
.nav-cta .arrow { transition: transform .25s; }
.nav-cta:hover .arrow { transform: translateX(4px); }

/* mobile nav button */
.menu-toggle {
  display: none;
  background: transparent; border: none;
  cursor: pointer; padding: 8px;
  color: inherit;
}
.menu-toggle span {
  display: block; width: 28px; height: 1.5px; background: currentColor;
  margin: 6px 0;
  transition: transform .3s, opacity .3s;
}
.menu-toggle.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* mobile nav drawer */
.mobile-nav {
  position: fixed; inset: 0;
  background: var(--paper);
  z-index: 40;
  padding: 96px 32px 48px;
  display: flex; flex-direction: column; justify-content: space-between;
  transform: translateX(100%);
  transition: transform .45s cubic-bezier(.7,0,.2,1);
  visibility: hidden;
}
.mobile-nav.open { transform: translateX(0); visibility: visible; }
.mobile-nav-list {
  display: flex; flex-direction: column; gap: 4px;
  list-style: none; margin: 0; padding: 0;
}
.mobile-nav-list a {
  display: flex; align-items: baseline; gap: 14px;
  padding: 18px 0;
  font-family: var(--serif);
  font-size: 32px; font-weight: 500;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--navy-deep);
  border-bottom: 1px solid var(--line);
}
.mobile-nav-list a .num {
  font-family: var(--sans);
  font-size: 11px; letter-spacing: 0.3em;
  color: var(--accent);
  font-weight: 500;
  flex: 0 0 auto;
}
.mobile-nav-foot {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--navy);
  opacity: 0.7;
  line-height: 1.8;
  letter-spacing: 0.04em;
}

/* FOOTER ================================================================ */

.site-footer {
  background: var(--navy-deep);
  color: rgba(245, 242, 236, 0.7);
  font-family: var(--sans);
  padding: 80px 48px 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(245, 242, 236, 0.1);
}
.footer-brand {
  font-family: var(--serif);
  font-size: 22px;
  color: var(--paper);
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}
.footer-brand-en {
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.4em;
  color: var(--accent);
  margin-bottom: 24px;
}
.footer-addr { font-size: 12px; line-height: 2; }
.footer-col-title {
  font-size: 10px; letter-spacing: 0.3em;
  color: var(--paper); opacity: 0.55;
  margin-bottom: 18px;
  text-transform: uppercase;
}
.footer-link {
  display: block;
  font-size: 13px;
  margin-bottom: 10px;
  text-decoration: none;
  color: rgba(245, 242, 236, 0.7);
  transition: color .2s;
}
.footer-link:hover { color: var(--accent); }
.footer-bottom {
  padding-top: 28px;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 11px; letter-spacing: 0.15em; opacity: 0.5;
}

/* SECTION HEADER ======================================================== */

.section-head {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 80px;
  margin-bottom: 80px;
  align-items: end;
}
.section-head-title {
  font-family: var(--serif);
  font-size: clamp(48px, 5.5vw, 72px);
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1;
  margin: 24px 0 0;
  color: var(--navy-deep);
}
.section-head-title em {
  color: var(--accent);
  font-weight: 400;
}
.section-head-lede {
  font-family: var(--sans);
  font-size: 14px; line-height: 2;
  font-weight: 300;
  max-width: 540px;
  color: var(--navy);
}

/* PAGE HEADER (sub-pages) =============================================== */

.page-hero {
  position: relative;
  padding: 96px 48px 96px;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}
.page-hero::before {
  content: "";
  position: absolute;
  top: 0; right: -100px;
  font-size: 0;
  width: 480px; height: 480px;
  background: radial-gradient(circle at center, rgba(201, 169, 110, 0.08) 0%, transparent 60%);
  pointer-events: none;
}
.crumbs {
  font-family: var(--sans);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--navy);
  opacity: 0.6;
  margin-bottom: 32px;
  display: flex; gap: 14px;
  text-transform: uppercase;
}
.crumbs a { text-decoration: none; transition: opacity .2s; }
.crumbs a:hover { opacity: 1; color: var(--accent); }
.crumbs .sep { opacity: 0.4; }

.page-title {
  font-family: var(--serif);
  font-size: clamp(56px, 8vw, 120px);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 0.95;
  margin: 0;
  color: var(--navy-deep);
}
.page-title em { color: var(--accent); font-weight: 400; }
.page-title-en {
  display: block;
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: 0.5em;
  color: var(--navy);
  opacity: 0.5;
  text-transform: uppercase;
  margin-top: 24px;
  font-weight: 500;
}
.page-lede {
  font-family: var(--sans);
  font-size: 15px;
  line-height: 2;
  font-weight: 300;
  max-width: 580px;
  margin-top: 32px;
  color: var(--navy);
}

/* BUTTONS =============================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 18px 28px;
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-decoration: none;
  text-transform: uppercase;
  transition: transform .25s, background .25s, color .25s, border-color .25s;
  cursor: pointer;
  border: 1px solid transparent;
}
.btn .arrow { transition: transform .3s cubic-bezier(.7,0,.2,1); }
.btn:hover .arrow { transform: translateX(6px); }

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

.btn-dark {
  background: var(--navy);
  color: var(--paper);
}
.btn-dark:hover { background: var(--navy-deep); }

.btn-outline-light {
  background: transparent;
  color: var(--paper);
  border-color: rgba(245, 242, 236, 0.4);
}
.btn-outline-light:hover {
  background: var(--paper);
  color: var(--navy-deep);
  border-color: var(--paper);
}

.btn-outline-dark {
  background: transparent;
  color: var(--navy);
  border-color: var(--navy);
}
.btn-outline-dark:hover {
  background: var(--navy);
  color: var(--paper);
}

/* SCROLL REVEAL ========================================================= */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .9s cubic-bezier(.2,.7,.3,1), transform .9s cubic-bezier(.2,.7,.3,1);
  transition-delay: var(--reveal-delay, 0ms);
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}

.reveal-mask {
  display: inline-block;
  overflow: hidden;
  vertical-align: bottom;
}
.reveal-mask > span {
  display: inline-block;
  transform: translateY(110%);
  transition: transform 1s cubic-bezier(.7,0,.2,1);
  transition-delay: var(--reveal-delay, 0ms);
}
.reveal-mask.in > span { transform: translateY(0); }

/* MARQUEE =============================================================== */

@keyframes marquee {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

.marquee {
  background: var(--navy-deep);
  color: var(--paper);
  padding: 24px 0;
  overflow: hidden;
  white-space: nowrap;
  border-top: 1px solid rgba(201, 169, 110, 0.2);
  border-bottom: 1px solid rgba(201, 169, 110, 0.2);
}
.marquee-track {
  display: inline-flex;
  gap: 48px;
  animation: marquee 50s linear infinite;
  font-family: var(--serif);
  font-size: clamp(24px, 3vw, 38px);
  letter-spacing: -0.01em;
  align-items: center;
  font-weight: 500;
}
.marquee-track .sep {
  color: var(--accent);
  font-style: italic;
  font-weight: 300;
}

/* PROJECT CARD ========================================================== */

.proj-card {
  position: relative;
  overflow: hidden;
  cursor: pointer;
  background: var(--navy-deep);
  text-decoration: none;
  color: var(--paper);
  display: block;
}
.proj-card .img {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  filter: saturate(0.78) contrast(1.05);
  transition: transform 1s cubic-bezier(.2,.7,.3,1);
}
.proj-card image-slot {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  --slot-bg: rgba(10,31,61,0.4);
}
.proj-card:hover .img { transform: scale(1.06); }
.proj-card .scrim {
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(6,19,40,0) 35%, rgba(6,19,40,0.92) 100%);
  pointer-events: none;
}
.proj-card .top {
  position: absolute; top: 22px; left: 22px; right: 22px;
  display: flex; justify-content: space-between;
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.3em;
  font-weight: 500;
}
.proj-card .top .num { color: var(--accent); }
.proj-card .top .loc { opacity: 0.85; }
.proj-card .body {
  position: absolute; bottom: 22px; left: 22px; right: 22px;
}
.proj-card .body .cat {
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.3em;
  opacity: 0.75;
  margin-bottom: 8px;
  text-transform: uppercase;
  font-weight: 500;
}
.proj-card .body .title {
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 500;
  letter-spacing: -0.01em;
  line-height: 1.35;
}

/* RESPONSIVE ============================================================ */

@media (max-width: 960px) {
  .site-header,
  .site-header.scrolled { padding: 16px 20px; }
  .brand-mark { width: 38px; height: 38px; font-size: 20px; }
  .brand-text { font-size: 14px; }
  .brand-en { font-size: 8px; }
  .nav { display: none; }
  .menu-toggle { display: block; }

  .site-footer { padding: 48px 20px 24px; }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    padding-bottom: 32px;
  }
  .footer-brand-block { grid-column: 1 / -1; margin-bottom: 16px; }
  .footer-bottom {
    flex-direction: column; gap: 12px; align-items: flex-start;
    text-align: left;
  }

  .section-head {
    grid-template-columns: 1fr;
    gap: 24px;
    margin-bottom: 48px;
  }
  .section-head-title { font-size: clamp(36px, 9vw, 56px); }

  .page-hero { padding: 64px 20px; }
  .page-title { font-size: clamp(44px, 12vw, 80px); }
  .page-lede { font-size: 14px; }
}

@media (min-width: 961px) {
  .mobile-nav { display: none; }
}