/* 水処理業界サイト専用スタイル */
:root {
  --primary-color: #0078bf;        /* 水色ブルー */
  --secondary-color: #00aae4;      /* 明るい水色 */
  --accent-color: #00c4a7;         /* ティールグリーン */
  --text-dark: #2c3e50;            /* ダークブルーグレー */
  --text-light: #5a6c7d;           /* ライトブルーグレー */
  --background-light: #f0f8ff;     /* 非常に薄い水色 */
  --white: #ffffff;
  --gradient-primary: linear-gradient(135deg, #0078bf 0%, #00aae4 100%);
  --gradient-accent: linear-gradient(45deg, #00c4a7 0%, #26d0ce 100%);
  --shadow-light: rgba(0, 120, 191, 0.1);
  --shadow-medium: rgba(0, 120, 191, 0.2);
}

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

body {
  font-family: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', 'Yu Gothic Medium', 'Meiryo', sans-serif;
  line-height: 1.7;
  color: var(--text-dark);
  background-color: var(--white);
  overflow-x: hidden;
}

/* Header & Navigation */
.header {
  background: var(--gradient-primary);
  color: var(--white);
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000;
  box-shadow: 0 4px 20px var(--shadow-medium);
  backdrop-filter: blur(10px);
  transition: all 0.3s ease;
}

.header-container {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
}

.logo h1 {
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.logo span {
  color: var(--accent-color);
  font-weight: 300;
}

.nav {
  display: flex;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 2rem;
  align-items: center;
}

.nav-link {
  color: var(--white);
  text-decoration: none;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 25px;
  transition: all 0.3s ease;
  position: relative;
}

.nav-link:hover {
  background-color: rgba(255, 255, 255, 0.1);
  color: var(--accent-color);
}

.nav-link.active {
  background: var(--gradient-accent);
  color: var(--white);
}

/* Dropdown Menu */
.dropdown {
  position: relative;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--white);
  border-radius: 12px;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
  min-width: 250px;
  padding: 1rem 0;
  z-index: 100;
  border: 1px solid rgba(0, 120, 191, 0.1);
}

.dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-menu li {
  list-style: none;
}

.dropdown-menu a {
  display: block;
  padding: 0.8rem 1.5rem;
  color: var(--text-dark);
  text-decoration: none;
  transition: all 0.3s ease;
  font-size: 0.95rem;
  border-radius: 8px;
  margin: 0 0.5rem;
}

.dropdown-menu a:hover {
  background: var(--background-light);
  color: var(--primary-color);
  transform: translateX(5px);
}

/* Hamburger Menu */
.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
  padding: 0.5rem;
}

.bar {
  width: 25px;
  height: 3px;
  background: var(--white);
  margin: 3px 0;
  transition: all 0.3s ease;
  border-radius: 2px;
}

.hamburger.active .bar:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active .bar:nth-child(2) {
  opacity: 0;
}

.hamburger.active .bar:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

/* Main Content */
main {
  margin-top: 80px;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  color: var(--white);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(0, 120, 191, 0.8) 0%, rgba(0, 170, 228, 0.6) 100%);
  z-index: 1;
}

.hero::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 70% 30%, rgba(0, 196, 167, 0.3) 0%, transparent 50%);
  z-index: 2;
}

.hero-container {
  position: relative;
  z-index: 3;
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.hero-title {
  font-size: 4rem;
  font-weight: 800;
  margin-bottom: 1rem;
  line-height: 1.1;
  text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font-size: 1.8rem;
  font-weight: 400;
  margin-bottom: 2rem;
  opacity: 0.95;
}

.hero-description {
  font-size: 1.2rem;
  font-weight: 300;
  margin-bottom: 3rem;
  line-height: 1.6;
  opacity: 0.9;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
}

.stat-item {
  text-align: center;
  background: rgba(255, 255, 255, 0.1);
  padding: 2rem 1rem;
  border-radius: 15px;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  transition: all 0.3s ease;
}

.stat-item:hover {
  transform: translateY(-5px);
  background: rgba(255, 255, 255, 0.15);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent-color);
  display: block;
  margin-bottom: 0.5rem;
}

.stat-label {
  font-size: 1rem;
  font-weight: 500;
  color: var(--white);
}

.cta-button {
  display: inline-block;
  background: var(--gradient-accent);
  color: var(--white);
  padding: 1.2rem 2.5rem;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.1rem;
  transition: all 0.3s ease;
  box-shadow: 0 8px 25px rgba(0, 196, 167, 0.3);
}

.cta-button:hover {
  transform: translateY(-3px);
  box-shadow: 0 15px 35px rgba(0, 196, 167, 0.4);
}

/* Container */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Section Common Styles */
.section {
  padding: 6rem 0;
  position: relative;
}

.section:nth-child(even) {
  background: var(--background-light);
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

.section-title {
  font-size: 2.8rem;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 1.5rem;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -15px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: var(--gradient-accent);
  border-radius: 2px;
}

.section-subtitle {
  font-size: 1.2rem;
  color: var(--text-light);
  max-width: 700px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Overview Section */
.overview-section {
  background: linear-gradient(135deg, var(--background-light) 0%, var(--white) 100%);
}

.overview-content p {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text-dark);
  margin-bottom: 1.5rem;
  text-align: center;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

/* News Section */
.news-section {
  background: var(--white);
}

.news-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.news-card {
  background: var(--white);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: 0 15px 35px var(--shadow-light);
  transition: all 0.3s ease;
  border: 1px solid rgba(0, 120, 191, 0.1);
  position: relative;
  overflow: hidden;
}

.news-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-accent);
}

.news-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 25px 50px var(--shadow-medium);
}

.news-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  display: block;
}

.news-title {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 1rem;
  line-height: 1.4;
}

.news-content {
  font-size: 1rem;
  color: var(--text-light);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.news-date {
  font-size: 0.9rem;
  color: var(--accent-color);
  font-weight: 500;
  background: rgba(0, 196, 167, 0.1);
  padding: 0.3rem 0.8rem;
  border-radius: 15px;
  display: inline-block;
}

/* Technology Section */
.tech-section {
  background: var(--background-light);
}

.tech-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.tech-card {
  background: var(--white);
  border-radius: 20px;
  padding: 2.5rem;
  text-align: center;
  box-shadow: 0 15px 35px var(--shadow-light);
  transition: all 0.4s ease;
  border: 1px solid rgba(0, 120, 191, 0.1);
  position: relative;
  overflow: hidden;
}

.tech-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-accent);
}

.tech-card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: 0 25px 50px var(--shadow-medium);
}

.tech-icon {
  font-size: 3rem;
  margin-bottom: 1.5rem;
  display: block;
}

.tech-title {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.tech-content {
  font-size: 1rem;
  color: var(--text-light);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.tech-link {
  color: var(--accent-color);
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.tech-link:hover {
  color: var(--primary-color);
  transform: translateX(5px);
}

/* Stats Section */
.stats-section {
  background: var(--white);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.stat-card {
  text-align: center;
  background: var(--white);
  padding: 2.5rem 1.5rem;
  border-radius: 15px;
  box-shadow: 0 15px 35px var(--shadow-light);
  transition: all 0.3s ease;
  border: 1px solid rgba(0, 120, 191, 0.1);
}

.stat-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 25px 50px var(--shadow-medium);
}

.stat-card .stat-number {
  font-size: 2.8rem;
  font-weight: 800;
  color: var(--primary-color);
  display: block;
  margin-bottom: 0.5rem;
}

.stat-card .stat-label {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 0.5rem;
}

.stat-desc {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.5;
}

/* Footer */
.footer {
  background: var(--primary-color);
  color: var(--white);
  padding: 4rem 0 2rem;
  margin-top: 0;
}

.footer-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 3rem;
  margin-bottom: 2rem;
}

.footer-section {
  text-align: left;
}

.footer-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--accent-color);
}

.footer-subtitle {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--secondary-color);
}

.footer-description {
  font-size: 1rem;
  line-height: 1.6;
  opacity: 0.8;
  margin-bottom: 1rem;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  color: var(--white);
  text-decoration: none;
  transition: all 0.3s ease;
  opacity: 0.8;
}

.footer-links a:hover {
  color: var(--accent-color);
  opacity: 1;
  padding-left: 0.5rem;
}

.footer-bottom {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  font-size: 0.9rem;
  opacity: 0.7;
}

.footer-links-bottom {
  margin-bottom: 1rem;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer-links-bottom a {
  color: var(--white);
  text-decoration: none;
  transition: all 0.3s ease;
  opacity: 0.9;
  font-size: 0.9rem;
}

.footer-links-bottom a:hover {
  color: var(--accent-color);
  opacity: 1;
}

.footer-links-bottom .separator {
  color: var(--white);
  opacity: 0.5;
  margin: 0 0.3rem;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
  .footer-links-bottom {
    flex-direction: column;
    gap: 0.8rem;
  }

  .footer-links-bottom .separator {
    display: none;
  }
}

/* Page-specific Hero */
.page-hero {
  min-height: 70vh;
  display: flex;
  align-items: center;
  background-size: cover;
  background-position: center;
  color: var(--white);
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(0, 120, 191, 0.7) 0%, rgba(0, 170, 228, 0.5) 100%);
  z-index: 1;
}

.page-hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
  padding: 0 2rem;
}

.page-hero h1 {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 1rem;
  line-height: 1.2;
  text-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.page-hero .subtitle {
  font-size: 1.3rem;
  font-weight: 300;
  opacity: 0.9;
}

/* Content Section */
.content-section {
  padding: 5rem 0;
}

.content-section h3 {
  font-size: 2rem;
  font-weight: 600;
  color: var(--primary-color);
  margin: 3rem 0 1.5rem;
  border-bottom: 3px solid var(--accent-color);
  padding-bottom: 0.5rem;
  display: inline-block;
}

.content-section p {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text-dark);
  margin-bottom: 1.5rem;
}

.content-section ul {
  list-style: none;
  padding-left: 0;
}

.content-section li {
  margin-bottom: 1rem;
  padding: 0.8rem 0 0.8rem 2.5rem;
  position: relative;
  font-size: 1rem;
  line-height: 1.6;
  border-bottom: 1px solid rgba(0, 120, 191, 0.1);
}

.content-section li::before {
  content: '💧';
  position: absolute;
  left: 0;
  font-size: 1.2rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 3rem;
  }
  
  .section-title {
    font-size: 2.3rem;
  }
  
  .hero-stats {
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }
  
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--primary-color);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    border-radius: 0 0 15px 15px;
  }
  
  .nav.active {
    display: block;
  }
  
  .nav-list {
    flex-direction: column;
    gap: 0;
    padding: 1rem 0;
  }
  
  .nav-link {
    display: block;
    padding: 1rem 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0;
  }
  
  .dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    background: rgba(255, 255, 255, 0.1);
    margin: 0.5rem 2rem;
    border-radius: 8px;
  }
  
  .dropdown-menu a {
    color: var(--white);
    padding: 0.8rem 1rem;
    margin: 0;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.4rem;
  }
  
  .hero-description {
    font-size: 1rem;
  }
  
  .page-hero h1 {
    font-size: 2.2rem;
  }
  
  .section {
    padding: 4rem 0;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .container {
    padding: 0 1rem;
  }
  
  .header-container {
    padding: 1rem;
  }
  
  .hero-stats {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .tech-grid,
  .news-grid,
  .stats-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero {
    min-height: 80vh;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1.2rem;
  }
  
  .hero-description {
    font-size: 0.95rem;
  }
  
  .hero-content,
  .page-hero-content {
    padding: 0 1rem;
  }
  
  .section {
    padding: 3rem 0;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
  
  .news-card,
  .tech-card,
  .stat-card {
    padding: 1.5rem;
  }
  
  .cta-button {
    padding: 1rem 2rem;
    font-size: 1rem;
  }
}

/* Loading and Animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeInUp 0.6s ease-out;
}

/* Water effect animation */
@keyframes waterFlow {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.water-effect::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent-color), transparent);
  animation: waterFlow 2s infinite;
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* Image optimization */
img {
  max-width: 100%;
  height: auto;
  transition: opacity 0.3s ease;
}

img[loading="lazy"] {
  opacity: 0;
}

img[loading="lazy"].loaded {
  opacity: 1;
}