/* ========================================
   Hydraulic Pulse Design System
   産業用ホース・継手専門サイト
   Deep Crimson × Brushed Steel × Dark Graphite
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;500;600;700;800;900&family=Outfit:wght@400;500;600;700;800;900&display=swap');

:root {
  --crimson: #9b1b30;
  --crimson-dark: #7a1526;
  --crimson-light: #c22a42;
  --steel: #c0c0c0;
  --steel-light: #d9d9d9;
  --steel-dark: #8a8a8a;
  --graphite: #2b2b2b;
  --graphite-deep: #1a1a1a;
  --graphite-light: #3d3d3d;
  --white: #ffffff;
  --off-white: #f5f5f5;
  --text-dark: #1a1a1a;
  --text-body: #333333;
  --text-muted: #666666;
  --text-light: #e0e0e0;
  --font-heading: 'Outfit', 'Noto Sans JP', sans-serif;
  --font-body: 'Noto Sans JP', 'Outfit', sans-serif;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.15);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.2);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.3);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --header-height: 70px;
  --max-width: 1200px;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: var(--font-body); color: var(--text-body); background: var(--off-white); line-height: 1.8; -webkit-font-smoothing: antialiased; }
a { color: var(--crimson); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: var(--crimson-light); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* --- Header --- */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: var(--graphite-deep);
  height: var(--header-height);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}
.header.scrolled {
  background: rgba(26,26,26,0.97);
  box-shadow: 0 2px 20px rgba(155,27,48,0.3);
}
.header-inner {
  max-width: var(--max-width); margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.logo { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--white); }
.logo-icon { font-size: 1.5rem; }
.logo-text { font-family: var(--font-heading); font-size: 1.25rem; font-weight: 800; color: var(--white); letter-spacing: 0.5px; }
.logo-text span { color: var(--crimson-light); }
.nav-menu { display: flex; align-items: center; gap: 4px; }
.nav-menu li a {
  color: var(--steel-light); font-size: 0.85rem; font-weight: 500;
  padding: 8px 12px; border-radius: var(--radius-sm);
  transition: all 0.2s ease; white-space: nowrap;
}
.nav-menu li a:hover, .nav-menu li a.active { color: var(--white); background: var(--crimson); }

/* --- Hamburger --- */
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; z-index: 1001; }
.hamburger span { display: block; width: 24px; height: 2px; background: var(--white); transition: all 0.3s ease; border-radius: 2px; }
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* --- Hero (Homepage) --- */
.hero {
  position: relative; height: 600px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden; margin-top: var(--header-height);
}
.hero-bg { position: absolute; inset: 0; z-index: 0; }
.hero-bg img { width: 100%; height: 100%; object-fit: cover; }
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(26,26,26,0.6) 0%, rgba(155,27,48,0.35) 100%);
  z-index: 1;
}
.hero-content { position: relative; z-index: 2; text-align: center; padding: 0 24px; max-width: 800px; }
.hero-badge {
  display: inline-block; background: var(--crimson); color: var(--white);
  font-size: 0.8rem; font-weight: 700; padding: 6px 18px; border-radius: 30px;
  margin-bottom: 20px; letter-spacing: 1px;
}
.hero h1 {
  font-family: var(--font-heading); font-size: 3rem; font-weight: 900;
  color: var(--white); line-height: 1.3; margin-bottom: 16px;
  text-shadow: 2px 2px 8px rgba(0,0,0,0.7), 0 0 20px rgba(0,0,0,0.4);
}
.hero h1 span { color: var(--crimson-light); }
.hero-description {
  color: var(--steel-light); font-size: 1.05rem; line-height: 1.8;
  margin-bottom: 30px; text-shadow: 1px 1px 4px rgba(0,0,0,0.5);
}
.hero-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* --- Buttons --- */
.btn {
  display: inline-block; padding: 12px 28px; font-size: 0.95rem; font-weight: 700;
  border-radius: var(--radius-sm); transition: all 0.25s ease; cursor: pointer;
  text-decoration: none; border: 2px solid transparent;
}
.btn-primary { background: var(--crimson); color: var(--white); border-color: var(--crimson); }
.btn-primary:hover { background: var(--crimson-dark); border-color: var(--crimson-dark); color: var(--white); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; color: var(--white); border-color: var(--steel); }
.btn-outline:hover { background: var(--white); color: var(--graphite); border-color: var(--white); transform: translateY(-2px); }

/* --- Stats --- */
.stats { background: var(--graphite); padding: 40px 0; border-bottom: 3px solid var(--crimson); }
.stats-grid { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.stat-item { text-align: center; padding: 20px; }
.stat-number { font-family: var(--font-heading); font-size: 2.2rem; font-weight: 900; color: var(--crimson-light); margin-bottom: 4px; }
.stat-label { color: var(--steel); font-size: 0.85rem; font-weight: 500; }

/* --- Sections --- */
.section { padding: 80px 0; }
.section-dark { background: var(--graphite); color: var(--text-light); }
.section-title { font-family: var(--font-heading); font-size: 2rem; font-weight: 800; text-align: center; margin-bottom: 8px; }
.section-dark .section-title { color: var(--white); }
.section-title::after { content: ''; display: block; width: 60px; height: 3px; background: var(--crimson); margin: 12px auto 0; }
.section-subtitle { text-align: center; color: var(--text-muted); font-size: 0.95rem; margin-bottom: 48px; }
.section-dark .section-subtitle { color: var(--steel-dark); }

/* --- Features Grid --- */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card { background: var(--graphite-light); border-radius: var(--radius-md); overflow: hidden; transition: transform 0.3s ease, box-shadow 0.3s ease; border: 1px solid rgba(192,192,192,0.1); }
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 12px 30px rgba(155,27,48,0.2); }
.feature-image { position: relative; height: 200px; overflow: hidden; }
.feature-image img { width: 100%; height: 100%; object-fit: cover; }
.feature-tag { position: absolute; top: 12px; left: 12px; background: var(--crimson); color: var(--white); font-size: 0.75rem; font-weight: 700; padding: 4px 12px; border-radius: var(--radius-sm); }
.feature-content { padding: 20px; }
.feature-content h3 { font-family: var(--font-heading); font-size: 1.1rem; font-weight: 700; color: var(--white); margin-bottom: 8px; }
.feature-content p { color: var(--steel); font-size: 0.9rem; line-height: 1.7; margin-bottom: 12px; }
.feature-link { color: var(--crimson-light); font-size: 0.85rem; font-weight: 600; }
.feature-link:hover { color: var(--white); }

/* --- Topics Grid --- */
.topics-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.topic-card { display: flex; align-items: center; gap: 14px; padding: 20px; background: var(--graphite-light); border-radius: var(--radius-md); border: 1px solid rgba(192,192,192,0.1); transition: all 0.25s ease; text-decoration: none; }
.topic-card:hover { border-color: var(--crimson); transform: translateY(-3px); box-shadow: 0 6px 20px rgba(155,27,48,0.15); }
.topic-icon { font-size: 2rem; flex-shrink: 0; }
.topic-content h4 { font-family: var(--font-heading); font-weight: 700; color: var(--white); font-size: 0.95rem; margin-bottom: 4px; }
.topic-content p { color: var(--steel-dark); font-size: 0.8rem; line-height: 1.5; }

/* --- News Grid --- */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.news-card { background: var(--white); border-radius: var(--radius-md); overflow: hidden; box-shadow: var(--shadow-sm); transition: transform 0.3s ease, box-shadow 0.3s ease; border: 1px solid #e5e5e5; }
.news-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.news-image { height: 160px; overflow: hidden; }
.news-image img { width: 100%; height: 100%; object-fit: cover; }
.news-content { padding: 20px; }
.news-date { color: var(--crimson); font-size: 0.8rem; font-weight: 600; margin-bottom: 8px; }
.news-content h4 { font-family: var(--font-heading); font-size: 1rem; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; line-height: 1.5; }
.news-content p { color: var(--text-muted); font-size: 0.85rem; line-height: 1.6; }

/* --- CTA --- */
.cta-section { background: linear-gradient(135deg, var(--crimson-dark) 0%, var(--crimson) 50%, var(--graphite) 100%); padding: 60px 0; text-align: center; }
.cta-content { max-width: 600px; margin: 0 auto; padding: 0 24px; }
.cta-content h2 { font-family: var(--font-heading); font-size: 1.8rem; font-weight: 800; color: var(--white); margin-bottom: 12px; }
.cta-content p { color: var(--steel-light); font-size: 0.95rem; margin-bottom: 24px; }

/* --- Footer --- */
.footer { background: var(--graphite-deep); color: var(--steel); padding: 48px 0 0; }
.footer-grid { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 40px; }
.footer-brand p { color: var(--steel-dark); font-size: 0.85rem; margin-top: 12px; line-height: 1.7; }
.footer-title { font-family: var(--font-heading); font-size: 0.95rem; font-weight: 700; color: var(--white); margin-bottom: 16px; }
.footer-links li { margin-bottom: 8px; }
.footer-links a { color: var(--steel-dark); font-size: 0.85rem; transition: color 0.2s ease; }
.footer-links a:hover { color: var(--crimson-light); }
.footer-bottom { border-top: 1px solid var(--graphite-light); padding: 20px 24px; max-width: var(--max-width); margin: 0 auto; display: flex; justify-content: space-between; align-items: center; }
.footer-bottom p { font-size: 0.8rem; color: var(--steel-dark); }
.footer-legal a { color: var(--steel-dark); font-size: 0.8rem; }

/* --- Breadcrumb --- */
.breadcrumb { margin-top: var(--header-height); background: var(--graphite); padding: 12px 0; border-bottom: 1px solid var(--graphite-light); }
.breadcrumb .container { font-size: 0.8rem; color: var(--steel-dark); }
.breadcrumb a { color: var(--steel); }
.breadcrumb a:hover { color: var(--crimson-light); }

/* --- Page Hero --- */
.page-hero { position: relative; height: 360px; display: flex; align-items: flex-end; background-size: cover; background-position: center; background-repeat: no-repeat; }
.page-hero-overlay { position: absolute; inset: 0; background: linear-gradient(to top, rgba(26,26,26,0.85) 0%, rgba(26,26,26,0.3) 60%, transparent 100%); display: flex; align-items: flex-end; padding-bottom: 40px; }
.page-hero h1 { font-family: var(--font-heading); font-size: 2.2rem; font-weight: 900; color: var(--white); text-shadow: 2px 2px 8px rgba(0,0,0,0.7); margin-bottom: 8px; }
.page-hero-subtitle { color: var(--steel-light); font-size: 1rem; text-shadow: 1px 1px 4px rgba(0,0,0,0.5); }
.page-hero-subtitle a { color: var(--steel-light); }

/* --- Main Layout --- */
.main-layout { display: flex; gap: 40px; padding-top: 40px; padding-bottom: 60px; }
.main-content { flex: 1; min-width: 0; }
.sidebar { width: 300px; flex-shrink: 0; }

/* --- Article Content --- */
.article-content { line-height: 1.9; }
.intro-section p { font-size: 1rem; line-height: 1.9; margin-bottom: 24px; padding: 20px; background: var(--white); border-left: 4px solid var(--crimson); border-radius: var(--radius-sm); }
.content-section { margin-bottom: 40px; }
.content-section h2 { font-family: var(--font-heading); font-size: 1.5rem; font-weight: 800; color: var(--text-dark); padding-bottom: 10px; border-bottom: 3px solid var(--crimson); margin-bottom: 20px; }
.content-section h3 { font-family: var(--font-heading); font-size: 1.15rem; font-weight: 700; color: var(--graphite); margin-top: 24px; margin-bottom: 12px; padding-left: 14px; border-left: 4px solid var(--crimson); }
.content-section p { margin-bottom: 16px; line-height: 1.9; }
.content-section ul, .content-section ol { margin: 16px 0; padding-left: 24px; }
.content-section ul { list-style: disc; }
.content-section ol { list-style: decimal; }
.content-section li { margin-bottom: 8px; line-height: 1.7; }
.glossary-link { color: var(--crimson); font-weight: 500; border-bottom: 1px dotted var(--crimson); }
.glossary-link:hover { color: var(--crimson-dark); border-bottom-style: solid; }

/* --- Amazon Banner --- */
.amazon-banner { margin: 24px 0; padding: 12px 16px; background: linear-gradient(135deg, var(--graphite) 0%, var(--graphite-light) 100%); border-radius: var(--radius-sm); border: 1px solid var(--graphite-light); text-align: center; }
.amazon-banner a { color: var(--steel-light); font-size: 0.85rem; font-weight: 600; }
.amazon-banner a:hover { color: var(--crimson-light); }

/* --- Sidebar --- */
.sidebar-widget { background: var(--white); border-radius: var(--radius-md); padding: 20px; margin-bottom: 24px; box-shadow: var(--shadow-sm); border: 1px solid #e5e5e5; }
.sidebar-widget h3 { font-family: var(--font-heading); font-size: 1rem; font-weight: 700; color: var(--graphite); margin-bottom: 12px; padding-bottom: 8px; border-bottom: 2px solid var(--crimson); }
.toc-list li { margin-bottom: 8px; }
.toc-list a { color: var(--text-body); font-size: 0.85rem; display: block; padding: 6px 10px; border-radius: var(--radius-sm); transition: all 0.2s ease; }
.toc-list a:hover { background: rgba(155,27,48,0.08); color: var(--crimson); }
.related-links li { margin-bottom: 8px; }
.related-links a { color: var(--crimson); font-size: 0.85rem; }
.ad-content { font-size: 0.85rem; color: var(--text-muted); line-height: 1.7; }

/* --- Animations --- */
.fade-in { opacity: 0; transform: translateY(20px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .topics-grid { grid-template-columns: repeat(2, 1fr); }
  .news-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root { --header-height: 60px; }
  .hamburger { display: flex; }
  .nav-menu {
    position: fixed; top: 0; right: -100%; width: 280px; height: 100vh;
    background: var(--graphite-deep); flex-direction: column;
    padding: 80px 24px 24px; gap: 4px; transition: right 0.35s ease;
    box-shadow: -4px 0 20px rgba(0,0,0,0.4); overflow-y: auto;
  }
  .nav-menu.active { right: 0; }
  .nav-menu li a { font-size: 0.95rem; padding: 12px 16px; display: block; }
  .hero { height: 480px; }
  .hero h1 { font-size: 2rem; }
  .hero-description { font-size: 0.9rem; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .stat-number { font-size: 1.8rem; }
  .section { padding: 48px 0; }
  .section-title { font-size: 1.5rem; }
  .features-grid, .topics-grid, .news-grid { grid-template-columns: 1fr; }
  .main-layout { flex-direction: column; }
  .sidebar { width: 100%; }
  .page-hero { height: 260px; }
  .page-hero h1 { font-size: 1.5rem; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .cta-content h2 { font-size: 1.4rem; }
}

@media (max-width: 480px) {
  .hero { height: 400px; }
  .hero h1 { font-size: 1.6rem; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .hero-cta { flex-direction: column; align-items: center; }
}