/* 逆变储能一体机选型手册 - 与文档一致的专业界面 */
:root {
  --bg: #ffffff;
  --bg-alt: #f8f9fa;
  --bg-card: #ffffff;
  --text: #1c1c1c;
  --text-muted: #5a5a5a;
  --accent: #2e7d32;
  --accent-light: #4caf50;
  --accent-hover: #1b5e20;
  --blue-start: #2c3e6b;
  --blue-end: #4a7c8c;
  --border: #dee2e6;
  --divider: #2e7d32;
  --radius: 8px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --font: Arial, "Microsoft YaHei", "PingFang SC", "SimHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 绿色分隔线 - 与手册一致 */
.section-title::after {
  content: '';
  display: block;
  width: 80px;
  height: 3px;
  background: var(--divider);
  margin: 12px auto 0;
}

/* Header - 白底绿字 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 2px solid var(--divider);
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.05em;
  color: var(--accent);
  text-decoration: none;
}
.logo-img {
  height: 36px;
  width: auto;
  display: block;
}
.logo-text {
  color: inherit;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 32px;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

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

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 8px;
}

/* Hero - 蓝色渐变 + 手册封面氛围 */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(165deg, var(--blue-start) 0%, #3d5a80 40%, var(--blue-end) 100%);
}

.hero-cover {
  position: absolute;
  inset: 0;
  background: url("images/image1.png") center bottom / contain no-repeat;
  opacity: 0.12;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: #fff;
}

.hero-catalog {
  font-size: 1rem;
  color: rgba(255,255,255,0.95);
  margin-bottom: 4px;
  font-weight: 500;
}

.hero-catalog::after {
  content: '';
  display: block;
  width: 120px;
  height: 2px;
  background: #4caf50;
  margin: 6px auto 0;
}

.hero h1 {
  font-size: clamp(1.85rem, 4.2vw, 2.6rem);
  font-weight: 700;
  margin-bottom: 14px;
  letter-spacing: 0.03em;
  color: #fff;
  text-shadow: 0 2px 8px rgba(0,0,0,0.15);
  line-height: 1.3;
}

.hero-sub {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.9);
  margin-bottom: 8px;
}

.hero-company {
  font-size: 0.95rem;
  color: rgba(255,255,255,0.85);
  margin-bottom: 32px;
}

.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
  font-family: var(--font);
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border: none;
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: translateY(-1px);
}

/* Sections - 白/浅灰背景 */
.section {
  padding: 80px 0;
  background: var(--bg);
}

.section:nth-of-type(even) {
  background: var(--bg-alt);
}

.section-title {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 48px;
  text-align: center;
  color: var(--text);
  letter-spacing: 0.02em;
}

/* About + Values 一体：左侧文案，右侧三张图 */
.about-values-wrap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  align-items: start;
}
@media (min-width: 992px) {
  .about-values-wrap {
    grid-template-columns: 1fr 320px;
    gap: 3rem;
  }
}

.about-values-content {
  min-width: 0;
}

.about-intro {
  margin-bottom: 2rem;
}
.about-intro h3,
.values-block h3 {
  font-size: 1.15rem;
  color: var(--accent);
  margin-bottom: 12px;
  font-weight: 700;
}
.about-intro p,
.about-intro strong {
  color: var(--text-muted);
}
.about-intro p {
  margin-bottom: 1rem;
}
.about-intro strong {
  color: var(--text);
}

.values-block {
  margin-top: 1.5rem;
}

.about-values-images {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  position: sticky;
  top: 1.5rem;
}
.about-values-images img {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  display: block;
}

/* About 保留（若别处用到） */
.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.about-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--shadow-sm);
}

.about-icon {
  font-size: 2rem;
  margin-bottom: 12px;
  color: var(--accent);
}

.about-card p {
  color: var(--text-muted);
}

.about-card strong {
  color: var(--text);
}

/* Values - 标题绿色 */
.values-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 28px;
}
@media (max-width: 500px) {
  .values-grid {
    grid-template-columns: 1fr;
  }
}

.value-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow-sm);
}

.value-item h3,
.value-item h4 {
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 8px;
  font-weight: 700;
}

.value-item p {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.advantages {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 34px;
  box-shadow: var(--shadow-sm);
}

.advantages h3,
.advantages h4 {
  margin-bottom: 16px;
  font-size: 1.1rem;
  color: var(--text);
  border-bottom: 2px solid var(--divider);
  padding-bottom: 8px;
  display: inline-block;
}

.advantages ul {
  list-style: none;
}

.advantages li {
  padding: 10px 0;
  padding-left: 24px;
  position: relative;
  color: var(--text-muted);
}

.advantages li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

/* Products - 与手册产品页一致 */
.products {
  background: var(--bg-alt);
}

.product-category {
  margin-bottom: 56px;
}

.product-category:last-of-type {
  margin-bottom: 0;
}

.category-title {
  font-size: 1.35rem;
  margin-bottom: 8px;
  color: var(--accent);
  font-weight: 700;
}

.category-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 2px;
  background: var(--divider);
  margin-top: 6px;
}

.category-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 20px;
  max-width: 720px;
  line-height: 1.7;
}

/* 产品系列前：图标 + 文字介绍（与手册一致） */
.category-intro {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 12px 24px;
  margin-bottom: 24px;
  list-style: none;
}

.category-intro-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.category-intro-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  color: var(--accent);
  flex-shrink: 0;
}

.category-intro-icon svg {
  width: 100%;
  height: 100%;
  display: block;
}

.category-intro-text {
  line-height: 1.4;
}

.product-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.product-cards.two-col {
  grid-template-columns: repeat(2, 1fr);
}

.product-cards.single {
  grid-template-columns: 1fr;
  max-width: 640px;
}

.product-card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px;
  transition: box-shadow 0.25s ease, border-color 0.25s ease, transform 0.2s ease;
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: inherit;
}

.product-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-md), 0 0 0 1px rgba(46, 125, 50, 0.08);
  transform: translateY(-2px);
}

.product-card-link {
  display: inline-block;
  margin-top: 14px;
  font-size: 0.875rem;
  color: var(--accent);
  font-weight: 600;
}

.product-card:hover .product-card-link {
  text-decoration: underline;
}

.product-card.wide {
  max-width: 100%;
}

.product-img-wrap {
  width: 100%;
  aspect-ratio: 4/3;
  border-radius: var(--radius);
  overflow: hidden;
  background: #f0f2f5;
  margin-bottom: 18px;
  border: 1px solid var(--border);
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.04);
}

.product-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform 0.3s ease;
}

.product-card:hover .product-img-wrap img {
  transform: scale(1.02);
}

.product-card h4 {
  font-size: 1.15rem;
  margin-bottom: 12px;
  color: var(--text);
  font-weight: 700;
  letter-spacing: 0.01em;
}

.product-card ul {
  list-style: none;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.product-card li {
  padding: 4px 0;
  padding-left: 16px;
  position: relative;
}

.product-card li::before {
  content: '·';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

/* Contact */
.contact {
  background: var(--bg);
}

.contact-box {
  max-width: 520px;
  margin: 0 auto;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 44px;
  box-shadow: var(--shadow-sm);
}

.contact-company {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 4px;
  text-align: center;
}

.contact-company-en {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 24px;
  text-align: center;
}

.contact-list {
  list-style: none;
  border-top: 1px solid var(--border);
  padding-top: 20px;
}

.contact-list li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 10px 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.contact-label {
  flex: 0 0 48px;
  font-weight: 600;
  color: var(--text);
  font-size: 0.9rem;
}

.contact-box a {
  color: var(--accent);
  text-decoration: none;
}

.contact-box a:hover {
  text-decoration: underline;
}

/* Footer - 绿色底边 */
.footer {
  border-top: 2px solid var(--divider);
  padding: 24px;
  text-align: center;
  background: var(--bg);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}
.footer-logo {
  height: 40px;
  width: auto;
}
.footer p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: fixed;
    top: 64px;
    right: -100%;
    width: 260px;
    height: calc(100vh - 64px);
    background: var(--bg-card);
    border-left: 1px solid var(--border);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    transition: right 0.25s;
    box-shadow: -4px 0 12px rgba(0,0,0,0.08);
  }

  .nav-links.open {
    right: 0;
  }

  .product-cards.two-col {
    grid-template-columns: 1fr;
  }

  .category-intro {
    grid-template-columns: 1fr;
    gap: 10px;
    margin-bottom: 20px;
  }

  .category-intro-item {
    font-size: 0.875rem;
  }

  .section {
    padding: 56px 0;
  }
}