/* ===== Sustainergy Corporate Site ===== */
:root {
  --navy-900: #0a1a33;
  --navy-800: #0f2547;
  --navy-700: #16345f;
  --navy-500: #2b5a94;
  --accent: #3fb6c9;
  --accent-soft: #e6f5f8;
  --text: #1c2533;
  --muted: #5b6678;
  --line: #dfe4ec;
  --bg: #ffffff;
  --bg-alt: #f4f6fa;
  --radius: 10px;
  --max: 1120px;
  --font: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  --font-en: "Montserrat", var(--font);
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.85;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--navy-500); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { line-height: 1.4; margin: 0 0 .6em; color: var(--navy-900); }
p { margin: 0 0 1em; }

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* ----- Header ----- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.logo { display: flex; align-items: center; gap: 10px; color: var(--navy-900); font-family: var(--font-en); font-weight: 700; font-size: 1.3rem; letter-spacing: .02em; }
.logo:hover { text-decoration: none; }
.logo small { display: block; font-family: var(--font); font-size: .68rem; font-weight: 400; color: var(--muted); letter-spacing: .05em; line-height: 1.2; }
.logo-mark { width: 36px; height: 36px; }

.nav ul { list-style: none; margin: 0; padding: 0; display: flex; gap: 32px; align-items: center; }
.nav a { color: var(--text); font-size: .92rem; font-weight: 500; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--navy-500); text-decoration: none; }
.nav a[aria-current="page"] { border-bottom: 2px solid var(--accent); padding-bottom: 4px; }
.nav .btn { color: #fff; padding: 10px 22px; }
.nav .btn:hover { color: #fff; }

.nav .lang { display: flex; gap: 2px; padding-left: 20px; border-left: 1px solid var(--line); }
.nav .lang a { font-family: var(--font-en); font-size: .78rem; font-weight: 600; color: var(--muted); padding: 4px 7px; border-radius: 4px; }
.nav .lang a.active { color: #fff; background: var(--navy-700); }
.nav .lang a:not(.active):hover { color: var(--navy-500); background: var(--accent-soft); }

/* Language-specific fonts */
html[lang="en"] { --font: "Inter", "Noto Sans JP", sans-serif; }
html[lang="en"] body { line-height: 1.75; }
html[lang="zh-Hant"] { --font: "Noto Sans TC", "Microsoft JhengHei", "PingFang TC", sans-serif; }

.nav-toggle { display: none; background: none; border: 0; width: 44px; height: 44px; cursor: pointer; padding: 10px; }
.nav-toggle span { display: block; height: 2px; background: var(--navy-900); margin: 6px 0; transition: .3s; }

/* ----- Buttons ----- */
.btn {
  display: inline-block; background: var(--navy-700); color: #fff;
  padding: 14px 32px; border-radius: 999px; font-weight: 600; font-size: .95rem;
  transition: background .2s, transform .2s;
}
.btn:hover { background: var(--navy-500); text-decoration: none; transform: translateY(-1px); }
.btn-outline { background: transparent; border: 1px solid rgba(255,255,255,.7); }
.btn-outline:hover { background: rgba(255,255,255,.12); }
.btn-accent { background: var(--accent); color: var(--navy-900); }
.btn-accent:hover { background: #5cc6d6; }

/* ----- Hero ----- */
.hero {
  position: relative; overflow: hidden;
  background: radial-gradient(ellipse at 80% 20%, #1d4a85 0%, transparent 55%),
              linear-gradient(135deg, var(--navy-900) 0%, var(--navy-800) 60%, #123a6b 100%);
  color: #fff; padding: 120px 0 130px;
}
.hero .container { position: relative; z-index: 2; }
.hero-eyebrow { font-family: var(--font-en); letter-spacing: .25em; font-size: .8rem; color: var(--accent); font-weight: 600; margin-bottom: 20px; }
.hero h1 { color: #fff; font-size: clamp(2rem, 4.6vw, 3.4rem); font-weight: 700; letter-spacing: .02em; }
.hero p.lead { font-size: 1.08rem; color: rgba(255,255,255,.82); max-width: 620px; margin-bottom: 40px; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-bg { position: absolute; right: -80px; top: 50%; transform: translateY(-50%); width: 620px; opacity: .55; z-index: 1; pointer-events: none; }

/* ----- Page header (sub pages) ----- */
.page-header {
  background: linear-gradient(135deg, var(--navy-900), var(--navy-700));
  color: #fff; padding: 72px 0 64px;
}
.page-header .en { font-family: var(--font-en); color: var(--accent); letter-spacing: .25em; font-size: .8rem; font-weight: 600; }
.page-header h1 { color: #fff; font-size: clamp(1.7rem, 3.4vw, 2.4rem); margin: 6px 0 0; }
.breadcrumb { font-size: .8rem; color: rgba(255,255,255,.6); margin-top: 14px; }
.breadcrumb a { color: rgba(255,255,255,.8); }

/* ----- Sections ----- */
section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { text-align: center; margin-bottom: 56px; }
.section-title .en { display: block; font-family: var(--font-en); color: var(--accent); letter-spacing: .25em; font-size: .8rem; font-weight: 600; margin-bottom: 6px; }
.section-title h2 { font-size: clamp(1.5rem, 2.8vw, 2rem); margin: 0; }
.section-title p { color: var(--muted); margin-top: 14px; }

/* Message */
.message { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.message h2 { font-size: clamp(1.5rem, 2.6vw, 1.9rem); }
.message-visual { border-radius: var(--radius); overflow: hidden; background: var(--navy-800); aspect-ratio: 4/3; }

/* Business cards */
.cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 32px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; display: flex; flex-direction: column;
  transition: box-shadow .25s, transform .25s;
}
.card:hover { box-shadow: 0 14px 40px rgba(10,26,51,.1); transform: translateY(-3px); }
.card-visual { aspect-ratio: 16/9; background: var(--navy-800); }
.card-body { padding: 32px; flex: 1; display: flex; flex-direction: column; }
.card-body .num { font-family: var(--font-en); color: var(--accent); font-weight: 700; font-size: .85rem; letter-spacing: .15em; }
.card-body h3 { font-size: 1.35rem; margin: 6px 0 12px; }
.card-body p { color: var(--muted); flex: 1; }
.more { font-weight: 600; font-size: .92rem; }
.more::after { content: " →"; }

/* Strengths */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.feature { background: #fff; border-radius: var(--radius); padding: 36px 28px; border-top: 3px solid var(--navy-700); }
.feature .icon { width: 48px; height: 48px; border-radius: 12px; background: var(--accent-soft); display: grid; place-items: center; margin-bottom: 18px; color: var(--navy-700); }
.feature h3 { font-size: 1.1rem; }
.feature p { color: var(--muted); font-size: .94rem; margin: 0; }

/* News list */
.news-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.news-list li { display: grid; grid-template-columns: 120px 110px 1fr; gap: 16px; padding: 22px 8px; border-bottom: 1px solid var(--line); align-items: center; }
.news-list time { font-family: var(--font-en); color: var(--muted); font-size: .9rem; }
.tag { display: inline-block; font-size: .72rem; padding: 3px 10px; border-radius: 4px; background: var(--accent-soft); color: var(--navy-700); font-weight: 600; text-align: center; }
.center { text-align: center; margin-top: 40px; }

/* CTA */
.cta { background: linear-gradient(135deg, var(--navy-800), var(--navy-500)); color: #fff; text-align: center; padding: 88px 0; }
.cta h2 { color: #fff; font-size: clamp(1.4rem, 2.6vw, 1.9rem); }
.cta p { color: rgba(255,255,255,.82); margin-bottom: 32px; }

/* Business detail */
.biz-block { display: grid; grid-template-columns: 1.1fr 1fr; gap: 56px; align-items: center; }
.biz-block.reverse .biz-visual { order: 2; }
.biz-visual { border-radius: var(--radius); overflow: hidden; aspect-ratio: 4/3; background: var(--navy-800); }
.biz-block .label { font-family: var(--font-en); color: var(--accent); font-weight: 700; letter-spacing: .2em; font-size: .8rem; }
.biz-block h2 { font-size: clamp(1.4rem, 2.6vw, 1.9rem); margin-top: 6px; }
.checklist { list-style: none; padding: 0; margin: 24px 0 0; }
.checklist li { position: relative; padding-left: 30px; margin-bottom: 10px; }
.checklist li::before { content: ""; position: absolute; left: 0; top: .55em; width: 16px; height: 16px; border-radius: 50%; background: var(--accent-soft); border: 4px solid var(--accent); }
.flow { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; counter-reset: step; }
.flow-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 28px 22px; position: relative; }
.flow-item::before { counter-increment: step; content: "STEP " counter(step); font-family: var(--font-en); font-size: .75rem; font-weight: 700; color: var(--accent); letter-spacing: .15em; }
.flow-item h3 { font-size: 1.05rem; margin: 8px 0; }
.flow-item p { font-size: .9rem; color: var(--muted); margin: 0; }

/* Company table */
.info-table { width: 100%; border-collapse: collapse; }
.info-table th, .info-table td { padding: 22px 20px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.info-table th { width: 26%; background: var(--bg-alt); color: var(--navy-900); font-weight: 600; white-space: nowrap; }
.info-table tr:first-child th, .info-table tr:first-child td { border-top: 2px solid var(--navy-700); }
.todo { background: #fff4d6; color: #7a5a00; padding: 1px 6px; border-radius: 3px; font-size: .88em; }
.history { list-style: none; padding: 0; margin: 0; border-left: 2px solid var(--line); }
.history li { position: relative; padding: 0 0 28px 28px; }
.history li::before { content: ""; position: absolute; left: -7px; top: .55em; width: 12px; height: 12px; border-radius: 50%; background: var(--navy-700); }
.history time { font-family: var(--font-en); font-weight: 700; color: var(--navy-700); display: block; }
.map { margin-top: 32px; border-radius: var(--radius); overflow: hidden; aspect-ratio: 16/7; border: 1px solid var(--line); }
.map iframe { width: 100%; height: 100%; border: 0; display: block; }
@media (max-width: 900px) { .map { aspect-ratio: 4/3; } }
.map-placeholder { aspect-ratio: 16/7; background: var(--bg-alt); border: 1px dashed var(--line); border-radius: var(--radius); display: grid; place-items: center; color: var(--muted); margin-top: 32px; }

/* Contact form */
.form { max-width: 760px; margin: 0 auto; }
.form-row { margin-bottom: 24px; }
.form label { display: block; font-weight: 600; margin-bottom: 8px; color: var(--navy-900); }
.req { display: inline-block; background: #c0392b; color: #fff; font-size: .7rem; padding: 1px 8px; border-radius: 3px; margin-left: 8px; vertical-align: middle; }
.form input, .form select, .form textarea {
  width: 100%; padding: 14px 16px; border: 1px solid var(--line); border-radius: 6px;
  font: inherit; background: #fff; color: var(--text);
}
.form input:focus, .form select:focus, .form textarea:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent); }
.form textarea { min-height: 200px; resize: vertical; }
.form .agree { display: flex; gap: 10px; align-items: center; font-weight: 400; }
.form .agree input { width: auto; }
.form-note { background: var(--bg-alt); padding: 20px 24px; border-radius: var(--radius); font-size: .9rem; color: var(--muted); margin-bottom: 40px; }
.form-msg { display: none; padding: 16px 20px; border-radius: 6px; background: var(--accent-soft); color: var(--navy-800); margin-top: 20px; }

/* ----- Footer ----- */
.site-footer { background: var(--navy-900); color: rgba(255,255,255,.75); padding: 64px 0 28px; font-size: .9rem; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 48px; }
.site-footer .logo { color: #fff; }
.site-footer .logo small { color: rgba(255,255,255,.6); }
.footer-nav { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px 24px; }
.footer-nav a { color: rgba(255,255,255,.8); }
.copyright { border-top: 1px solid rgba(255,255,255,.12); margin-top: 48px; padding-top: 24px; font-size: .78rem; text-align: center; color: rgba(255,255,255,.5); font-family: var(--font-en); }

/* Fade-in */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .8s ease, transform .8s ease; }
.reveal.is-visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; transition: none; } html { scroll-behavior: auto; } }

/* ----- Responsive ----- */
@media (max-width: 900px) {
  .nav-toggle { display: block; }
  .nav {
    position: fixed; inset: 72px 0 auto 0; background: #fff;
    border-bottom: 1px solid var(--line); max-height: 0; overflow: hidden; transition: max-height .35s ease;
  }
  .nav.open { max-height: 420px; }
  .nav ul { flex-direction: column; gap: 0; padding: 12px 20px 24px; align-items: stretch; }
  .nav li a { display: block; padding: 14px 4px; border-bottom: 1px solid var(--line); }
  .nav a[aria-current="page"] { border-bottom: 1px solid var(--line); padding-bottom: 14px; }
  .nav .btn { text-align: center; margin-top: 16px; border: 0; }
  .nav .lang { border-left: 0; padding: 16px 0 0; justify-content: center; gap: 8px; }
  .nav .lang a { display: inline-block; border-bottom: 0; padding: 8px 16px; font-size: .9rem; }
  .nav.open { max-height: 480px; }
  .nav-toggle.open span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
  .nav-toggle.open span:nth-child(2) { opacity: 0; }
  .nav-toggle.open span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

  section { padding: 72px 0; }
  .hero { padding: 88px 0 96px; }
  .hero-bg { width: 420px; right: -160px; opacity: .3; }
  .message, .biz-block, .footer-grid { grid-template-columns: 1fr; gap: 36px; }
  .biz-block.reverse .biz-visual { order: 0; }
  .cards, .features { grid-template-columns: 1fr; }
  .flow { grid-template-columns: 1fr 1fr; }
  .news-list li { grid-template-columns: auto auto; gap: 6px 14px; }
  .news-list li a, .news-list li span.title { grid-column: 1 / -1; }
  .info-table th, .info-table td { display: block; width: 100%; }
  .info-table th { border-bottom: 0; padding: 12px 16px; }
  .info-table td { padding: 14px 16px 22px; }
  .info-table tr:first-child td { border-top: 0; }
}
@media (max-width: 520px) {
  .container { padding: 0 16px; }
  .flow { grid-template-columns: 1fr; }
  .card-body { padding: 24px; }
  .btn { padding: 13px 26px; }
}