/* ============================================================
   武汉青禾科技有限公司 — 三主题样式系统
   红色教育风（默认）| 蓝色商务风 | 黑色科技风
   ============================================================ */

/* --- 默认主题变量（红色教育风） --- */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f8f8;
    --bg-card: #ffffff;
    --bg-card-alt: #f5f5f5;
    --bg-card-hover: #fafafa;
    --border-color: #e0e0e0;
    --border-nav: #e0e0e0;
    --border-card: #eeeeee;
    --text-primary: #333333;
    --text-secondary: #555555;
    --text-muted: #888888;
    --text-footer: #999999;
    --accent: #C41E3A;
    --accent-hover: #A0152E;
    --accent-light: rgba(196, 30, 58, 0.06);
    --accent-glow: rgba(196, 30, 58, 0.1);
    --card-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    --card-shadow-hover: 0 8px 28px rgba(0, 0, 0, 0.12);
    --section-bg-alt: #f9f9f9;
    --header-height: 90px;
    --nav-height: 48px;
    --theme-dot-border: rgba(0,0,0,0.15);
    --hero-bg: linear-gradient(135deg, #f8f8f8 0%, #f0f0f0 100%);
    --nav-bg: #ffffff;
    --nav-link-color: #333333;
    --nav-link-hover-bg: rgba(0,0,0,0.04);
    --btn-text: #ffffff;
    --header-bg: #ffffff;
    --contact-shadow-hover: 0 4px 16px rgba(196,30,58,0.1);
}

/* --- 蓝色商务风 --- */
[data-theme="blue"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f0f4f8;
    --bg-card: #ffffff;
    --bg-card-alt: #eef3f8;
    --bg-card-hover: #e8eef5;
    --border-color: #c8d6e5;
    --border-nav: #1A5276;
    --border-card: #d5e0ee;
    --text-primary: #2c3e50;
    --text-secondary: #4a6b8a;
    --text-muted: #7f8fa6;
    --text-footer: #999999;
    --accent: #1A5276;
    --accent-hover: #0E3E5C;
    --accent-light: rgba(26, 82, 118, 0.08);
    --accent-glow: rgba(26, 82, 118, 0.12);
    --card-shadow: 0 2px 12px rgba(26, 82, 118, 0.10);
    --card-shadow-hover: 0 8px 28px rgba(26, 82, 118, 0.16);
    --section-bg-alt: #f0f4f8;
    --header-height: 90px;
    --nav-height: 48px;
    --theme-dot-border: rgba(26,82,118,0.25);
    --hero-bg: linear-gradient(135deg, #f0f4f8 0%, #e2ecf5 100%);
    --nav-bg: #1A5276;
    --nav-link-color: #ffffff;
    --nav-link-hover-bg: rgba(255,255,255,0.12);
    --btn-text: #ffffff;
    --header-bg: #ffffff;
    --contact-shadow-hover: 0 4px 16px rgba(26,82,118,0.15);
}
[data-theme="blue"] .nav-link.active {
    background: rgba(255, 255, 255, 0.18);
    color: #ffffff;
    box-shadow: inset 0 -3px 0 #ffffff;
    font-weight: 600;
}

/* --- 黑色科技风 --- */
[data-theme="dark"] {
    --bg-primary: #1a1a2e;
    --bg-secondary: #16213e;
    --bg-card: #1e2740;
    --bg-card-alt: #232d4a;
    --bg-card-hover: #283452;
    --border-color: #2a3556;
    --border-nav: #0f3460;
    --border-card: #2a3556;
    --text-primary: #e0e0e0;
    --text-secondary: #c0c8d8;
    --text-muted: #9aa0b8;
    --text-footer: #9aa0b8;
    --accent: #00d4ff;
    --accent-hover: #33ddff;
    --accent-light: rgba(0, 212, 255, 0.08);
    --accent-glow: rgba(0, 212, 255, 0.15);
    --card-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
    --card-shadow-hover: 0 8px 28px rgba(0, 0, 0, 0.4);
    --section-bg-alt: #16213e;
    --header-height: 90px;
    --nav-height: 48px;
    --theme-dot-border: rgba(0,212,255,0.25);
    --hero-bg: linear-gradient(135deg, #16213e 0%, #1a1a2e 100%);
    --nav-bg: #0f3460;
    --nav-link-color: #b0c4de;
    --nav-link-hover-bg: rgba(0,212,255,0.1);
    --btn-text: #1a1a2e;
    --header-bg: #1a1a2e;
    --contact-shadow-hover: 0 4px 16px rgba(0,212,255,0.15);
}
[data-theme="dark"] .nav-link.active {
    background: rgba(0, 212, 255, 0.14);
    box-shadow: inset 0 -3px 0 #00d4ff;
    font-weight: 700;
    color: #ffffff;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; overflow-y: scroll; background: var(--bg-secondary); }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    max-width: 1280px;
    margin: 0 auto;
    transition: background 0.35s, color 0.35s;
}
a { color: var(--accent); text-decoration: none; transition: color 0.3s; }
a:hover { color: var(--accent-hover); }
img { max-width: 100%; display: block; }

/* --- Utility --- */
.section { padding: 80px 0; }
.section-dark { background: var(--section-bg-alt); }
.section-inner { max-width: 1280px; margin: 0 auto; padding: 0 24px; }
.section-title {
    text-align: center;
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 48px;
    color: var(--text-primary);
    position: relative;
}
.section-title::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--accent);
    margin: 14px auto 0;
    border-radius: 2px;
}

/* === 双层 Header === */
.site-header {
    background: var(--header-bg);
    border-bottom: 1px solid var(--border-nav);
    height: var(--header-height);
    transition: background 0.35s, border-color 0.35s;
}
.header-inner {
    max-width: 1280px;
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
}

/* 左侧：校徽 + 校名（上行）+ 校训（下行） */
.header-left {
    display: flex;
    align-items: center;
    gap: 16px;
}
.header-logo {
    height: 52px;
    width: auto;
}
.header-brand-text {
    display: flex;
    flex-direction: column;
}
.header-company {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.3;
    transition: color 0.35s;
}
.header-slogan {
    font-size: 0.82rem;
    color: var(--text-muted);
    line-height: 1.4;
    margin-top: 2px;
    transition: color 0.35s;
}

/* 右侧：标题 + 主题选择器 */
.header-right {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 6px;
}
.header-title-main {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--accent);
    line-height: 1.3;
    transition: color 0.35s;
}
.header-title-sub {
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.4;
    transition: color 0.35s;
}

/* 主题切换器：三个小圆点 */
.theme-selector {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 3px 8px;
    border: 1px solid var(--theme-dot-border);
    border-radius: 16px;
    background: rgba(255,255,255,0.45);
    -webkit-backdrop-filter: blur(4px);
    backdrop-filter: blur(4px);
    margin-top: 4px;
}
.theme-dot {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    border: 2px solid rgba(255,255,255,0.7);
    cursor: pointer;
    transition: all 0.25s;
    position: relative;
    box-shadow: 0 0 2px rgba(0,0,0,0.15);
}
.theme-dot:hover { transform: scale(1.25); }
.theme-dot.active {
    border-color: var(--accent);
    box-shadow: 0 0 6px var(--accent-glow);
    transform: scale(1.15);
}
.theme-dot-red { background: #C41E3A; }
.theme-dot-blue { background: #1A5276; }
.theme-dot-dark { background: #1a1a2e; }

/* === 水平导航栏 === */
.site-nav {
    height: var(--nav-height);
    background: var(--nav-bg);
    border-bottom: 1px solid var(--border-nav);
    transition: background 0.35s, border-color 0.35s;
}
.nav-inner {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    padding: 0 24px;
    position: relative;
}
.nav-links {
    display: flex;
    align-items: center;
    height: 100%;
}
.nav-theme {
    position: absolute;
    right: 24px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 2px 8px;
    border: 1px solid var(--theme-dot-border);
    border-radius: 16px;
    background: rgba(128,128,128,0.08);
}
.nav-link {
    color: var(--nav-link-color);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    border-bottom: 3px solid transparent;
    transition: color 0.3s, border-color 0.3s, background 0.25s;
}
.nav-link:hover {
    color: var(--accent);
    background: var(--nav-link-hover-bg);
}
.nav-link.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
    font-weight: 600;
}

/* === 红色横幅（nav下方、iframe上方） === */
.site-banner {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%);
  color: #ffffff;
  text-align: center;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 0 24px;
  flex-shrink: 0;
}
.site-banner .banner-label {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 0;
  color: #ffffff;
  white-space: nowrap;
}
.site-banner .banner-desc {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.85);
  margin: 0;
  white-space: nowrap;
}

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 520px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
    background: var(--hero-bg);
    transition: background 0.5s;
}
.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    padding: 0 24px;
}
.hero-content h1 {
    font-size: 2.8rem;
    font-weight: 800;
    color: var(--accent);
    margin-bottom: 20px;
    letter-spacing: 2px;
    transition: color 0.35s;
}
.hero-content p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 36px;
    line-height: 1.8;
    transition: color 0.35s;
}
.hero-btn {
    display: inline-block;
    padding: 12px 36px;
    background: var(--accent);
    color: var(--btn-text);
    font-weight: 600;
    font-size: 1rem;
    border-radius: 4px;
    letter-spacing: 1px;
    transition: all 0.3s;
}
.hero-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    color: var(--btn-text);
}

/* --- About --- */
.about-content { max-width: 900px; margin: 0 auto; text-align: center; }
.about-content p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 2;
}

/* --- Qualifications --- */
.qual-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 14px;
    max-width: 900px;
    margin: 0 auto;
}
.qual-tag {
    padding: 8px 22px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    color: var(--text-secondary);
    font-size: 0.95rem;
    background: var(--bg-card);
    transition: all 0.3s;
}
.qual-tag:hover {
    border-color: var(--accent);
    color: var(--accent);
    box-shadow: 0 0 0 1px var(--accent);
}

/* --- Product Cards --- */
.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.product-card {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: 12px;
    padding: 36px 24px;
    text-align: center;
    transition: all 0.35s;
    box-shadow: var(--card-shadow);
}
.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--card-shadow-hover);
}
.product-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
}
.product-card p {
    font-size: 0.88rem;
    color: var(--text-muted);
    line-height: 1.7;
}

/* --- Cases --- */
.case-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; max-width: 1000px; margin: 0 auto; }
.case-item {
    padding: 16px 20px;
    background: var(--bg-card-alt);
    border: 1px solid var(--border-card);
    border-radius: 8px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    transition: all 0.3s;
}
.case-item:hover {
    border-color: var(--accent);
    background: var(--accent-light);
    color: var(--accent);
}

/* --- Contact --- */
.contact-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; max-width: 800px; margin: 0 auto; }
.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: 10px;
    box-shadow: var(--card-shadow);
    transition: all 0.3s;
}
.contact-item:hover {
    border-color: var(--accent);
    box-shadow: var(--contact-shadow-hover);
}
.contact-item h4 {
    font-size: 0.95rem;
    color: var(--accent);
    margin-bottom: 4px;
    font-weight: 600;
    transition: color 0.35s;
}
.contact-item p {
    font-size: 0.88rem;
    color: var(--text-muted);
}

/* --- Footer --- */
.site-footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: 20px 0;
    transition: background 0.35s, border-color 0.35s;
}
.footer-inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    gap: 24px;
}
.footer-links { display: flex; gap: 8px; align-items: center; }
.footer-links a { color: var(--text-muted); font-size: 0.85rem; white-space: nowrap; }
.footer-links a:hover { color: var(--accent); }
.footer-copy { color: var(--text-footer); font-size: 0.85rem; white-space: nowrap; }
.footer-icp { color: var(--text-footer); font-size: 0.85rem; white-space: nowrap; }
.footer-icp a { color: var(--text-footer); font-size: 0.85rem; white-space: nowrap; }
.footer-icp a:hover { color: var(--accent); }
.footer-sep { color: var(--text-muted); font-size: 0.8rem; }

/* --- 子页面通用 --- */
.page-header { text-align: center; padding: 32px 0 20px; border-bottom: 1px solid var(--border-color); }
.page-header h2 { font-size: 1.6rem; margin: 0 0 8px; color: var(--text-primary); }
.page-header .subtitle { font-size: 0.9rem; color: var(--text-muted); }

/* --- 统一标题横幅（深色背景 + 白色大标题 + 居中） --- */
.page-banner {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%);
  color: #ffffff;
  text-align: center;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 0 24px;
  flex-shrink: 0;
}
.page-banner h2 {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 0;
  color: #ffffff;
  white-space: nowrap;
}
.page-banner .subtitle {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.85);
  margin: 0;
  white-space: nowrap;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
    .product-grid { grid-template-columns: repeat(2, 1fr); }
    .case-list { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    :root,
    [data-theme="blue"],
    [data-theme="dark"] {
        --header-height: 140px;
    }
    .section { padding: 60px 0; }
    .section-title { font-size: 1.4rem; margin-bottom: 36px; }
    .hero-content h1 { font-size: 1.8rem; }
    .hero-content p { font-size: 0.95rem; }
    .product-grid { grid-template-columns: 1fr; }
    .case-list { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .footer-inner { flex-direction: column; gap: 10px; }
    .footer-links { flex-wrap: wrap; justify-content: center; gap: 6px; }

    .header-inner { flex-direction: column; justify-content: center; gap: 4px; padding: 6px 16px; }
    .header-left { gap: 10px; }
    .header-logo { height: 40px; }
    .header-company { font-size: 1.05rem; }
    .header-title-main { font-size: 1rem; }
    .header-right { align-items: center; }
    .nav-link { padding: 0 12px; font-size: 0.88rem; }
    .theme-selector { margin-top: 0; }
}
@media (max-width: 480px) {
    :root,
    [data-theme="blue"],
    [data-theme="dark"] {
        --header-height: 120px;
        --nav-height: 40px;
    }
    .header-company { font-size: 0.9rem; }
    .header-title-main { font-size: 0.85rem; }
    .header-title-sub { font-size: 0.72rem; }
    .nav-link { padding: 0 8px; font-size: 0.78rem; }
}