/* ================= 核心变量 (极光青主题) ================= */
:root {
    --primary: #0d9488;        
    --primary-hover: #0f766e;
    --primary-light: #f0fdfa;  
    --accent: #f97316;         
    --bg-body: #f4f7f9;        
    --bg-sidebar: rgba(255, 255, 255, 0.9); 
    --text-main: #334155;
    --text-dark: #0f172a;
    --text-sub: #64748b;
    --radius-main: 24px;       
    --shadow-soft: 0 10px 30px -10px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 20px 40px -10px rgba(13, 148, 136, 0.15);
    
    --cyan-grad: linear-gradient(135deg, #2dd4bf 0%, #0f766e 100%);
}

/* ================= 基础布局与全局美化 ================= */
html { scroll-behavior: smooth; }
* { margin: 0; padding: 0; box-sizing: border-box; outline: none; }
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 10px; border: 2px solid var(--bg-body); }
::-webkit-scrollbar-thumb:hover { background: var(--primary); }

body {
    font-family: 'Inter', "PingFang SC", "Microsoft YaHei", sans-serif;
    background-color: var(--bg-body);
    color: var(--text-main);
    font-size: 15px; line-height: 1.8; letter-spacing: 0.02em;
    background-image: radial-gradient(#cbd5e1 1px, transparent 1px);
    background-size: 32px 32px; position: relative; overflow-x: hidden;
}

/* 环境光晕 */
body::before, body::after {
    content: ''; position: fixed; filter: blur(150px); z-index: -1; 
    opacity: 0.5; border-radius: 50%; pointer-events: none;
}
body::before { top: -10%; left: -10%; width: 60vw; height: 60vw; background: radial-gradient(circle, #99f6e4, transparent 70%); }
body::after { bottom: -10%; right: -10%; width: 50vw; height: 50vw; background: radial-gradient(circle, #bae6fd, transparent 70%); }

ul, li { list-style: none; }
a { text-decoration: none; color: inherit; transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); cursor: pointer;}

/* 入场动画 */
@keyframes fadeUp { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }
.animate-up { animation: fadeUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards; opacity: 0; }
.delay-1 { animation-delay: 0.1s; } 
.delay-2 { animation-delay: 0.2s; } 
.delay-3 { animation-delay: 0.3s; } 
.delay-4 { animation-delay: 0.4s; }

/* ================= 侧边栏导航 ================= */
.g-sidenav {
    position: fixed; left: 24px; top: 24px; bottom: 24px; width: 270px; 
    background: var(--bg-sidebar); border-radius: var(--radius-main); z-index: 1000; display: flex; flex-direction: column;
    box-shadow: 0 20px 40px -10px rgba(0,0,0,0.04); border: 1px solid rgba(255,255,255,1); 
    backdrop-filter: blur(24px); overflow: hidden;
}
.brand-area { 
    height: 96px; display: flex; align-items: center; padding: 0 24px; 
    border-bottom: 1px dashed rgba(0,0,0,0.06); margin-bottom: 12px; position: relative;
}
.logo-icon {
    width: 44px; height: 44px; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    border-radius: 14px; display: flex; align-items: center; justify-content: center;
    margin-right: 14px; color: #fff; font-size: 20px; box-shadow: 0 8px 16px rgba(13, 148, 136, 0.25); flex-shrink: 0;
}
.logo-cn { font-size: 22px; font-weight: 900; letter-spacing: 2px; background: linear-gradient(to right, #0f172a, var(--primary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }

.nav-list { padding: 0 16px 20px; flex: 1; overflow-y: auto; scrollbar-width: none; }
.nav-list::-webkit-scrollbar { display: none; }
.nav-title { font-size: 12px; font-weight: 800; color: #94a3b8; padding: 0 12px; margin: 24px 0 12px 0; text-transform: uppercase; letter-spacing: 2px; display: flex; align-items: center; }
.nav-title::after { content: ''; flex: 1; height: 1px; background: linear-gradient(90deg, rgba(0,0,0,0.05), transparent); margin-left: 12px; }
.nav-list li { margin-bottom: 8px; }
.nav-list li a { display: flex; align-items: center; padding: 12px 14px; color: #475569; border-radius: 16px; font-weight: 600; font-size: 15px; letter-spacing: 0.05em; transition: all 0.3s; position: relative; }
.nav-list li a i { width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; margin-right: 14px; font-size: 16px; border-radius: 12px; background: rgba(0,0,0,0.03); color: #64748b; transition: all 0.3s; }
.nav-list li.active a { background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%); color: #fff; box-shadow: 0 8px 20px -6px rgba(13, 148, 136, 0.5); }
.nav-list li.active a i { background: rgba(255,255,255,0.25); color: #fff; box-shadow: 0 2px 8px rgba(0,0,0,0.1); }
.nav-list li:not(.active) a:hover { background: rgba(13, 148, 136, 0.06); color: var(--primary-hover); transform: translateX(6px); }
.nav-list li:not(.active) a:hover i { background: #fff; color: var(--primary); box-shadow: 0 4px 12px rgba(13, 148, 136, 0.12); transform: scale(1.08) rotate(3deg); }

/* ================= 悬浮子菜单 ================= */
.nav-submenu {
    position: fixed; background: rgba(255, 255, 255, 0.96); border: 1px solid rgba(255, 255, 255, 1);
    box-shadow: 0 15px 40px -5px rgba(13, 148, 136, 0.12); backdrop-filter: blur(24px); border-radius: 20px;
    padding: 24px; z-index: 1001; width: 440px; opacity: 0; visibility: hidden; transform: translateX(-15px);
    transition: all 0.3s; pointer-events: none; max-height: 85vh; overflow-y: auto;
}
.nav-submenu::-webkit-scrollbar { width: 4px; }
.nav-submenu::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 4px; }
.nav-submenu.show { opacity: 1; visibility: visible; transform: translateX(0); pointer-events: auto; }

#submenu-mobile { width: 620px; }
#submenu-mobile .submenu-grid { grid-template-columns: repeat(3, 1fr); }

.submenu-title { font-size: 16px; font-weight: 800; color: var(--text-dark); margin-bottom: 18px; padding-bottom: 14px; border-bottom: 1px dashed rgba(0,0,0,0.06); display: flex; align-items: center; gap: 10px; }
.submenu-title i { color: var(--primary); font-size: 18px; }
.submenu-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px 16px; }
.submenu-grid a { display: flex; align-items: center; gap: 10px; padding: 10px 14px; border-radius: 12px; color: var(--text-main); font-size: 13px; font-weight: 700; background: rgba(0,0,0,0.02); border: 1px solid transparent; transition: 0.3s;}
.submenu-grid a i { color: var(--text-sub); width: 18px; text-align: center; transition: 0.3s; }
.submenu-grid a:hover { background: var(--primary-light); color: var(--primary-hover); transform: translateX(4px); border-color: rgba(13, 148, 136, 0.1);}
.submenu-grid a:hover i { color: var(--primary); transform: scale(1.1); }

/* 主体容器 */
.main-container { margin-left: 320px; padding: 30px 40px 60px 10px; max-width: 1400px; margin-right: auto; overflow-x: hidden; }

/* 顶部导航与搜索 */
.top-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 40px; position: relative; z-index: 1000; }
.breadcrumb { font-size: 14px; font-weight: 600; color: #64748b; display: flex; align-items: center; gap: 8px;}
.breadcrumb a { color: var(--primary); }
.breadcrumb a:hover { color: var(--primary-hover); text-decoration: underline;}
.breadcrumb i { font-size: 12px; color: #cbd5e1;}

.search-wrapper { position: relative; flex: 1; max-width: 580px; display: flex; align-items: center; margin-left: auto;}
.search-input {
    width: 100%; height: 50px; padding: 0 100px 0 24px; border-radius: 25px;
    border: 1px solid rgba(255, 255, 255, 1); background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(20px); box-shadow: var(--shadow-soft);
    color: var(--text-dark); font-size: 14px; font-weight: 600; transition: all 0.4s ease;
}
.search-input:focus { background: #ffffff; border-color: var(--primary); box-shadow: 0 15px 35px -10px rgba(13, 148, 136, 0.25), 0 0 0 4px rgba(13, 148, 136, 0.1); }
.search-btn {
    position: absolute; right: 5px; top: 5px; bottom: 5px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: #fff; border-radius: 20px; padding: 0 24px; display: flex; align-items: center; justify-content: center;
    font-size: 13px; font-weight: 800; cursor: pointer; transition: all 0.3s ease; letter-spacing: 1px;
    box-shadow: 0 4px 12px rgba(13, 148, 136, 0.3);
}

/* ================= 了解门户页面专有内容 ================= */
.about-hero {
    background: linear-gradient(135deg, #0f172a 0%, #020617 100%);
    border-radius: 28px; padding: 60px; margin-bottom: 40px; color: #fff;
    box-shadow: 0 30px 60px -15px rgba(13, 148, 136, 0.3);
    position: relative; overflow: hidden;
}
.about-hero::before {
    content: ''; position: absolute; inset: 0;
    background: url('https://images.unsplash.com/photo-1542751371-adc38448a05e?w=1600&fit=crop') center/cover no-repeat;
    opacity: 0.1; mix-blend-mode: overlay; z-index: 0;
}
.about-hero-content { position: relative; z-index: 1; max-width: 850px; }
.about-hero-tag { display: inline-block; background: rgba(13, 148, 136, 0.2); border: 1px solid rgba(45, 212, 191, 0.4); padding: 6px 16px; border-radius: 30px; font-size: 13px; font-weight: 800; color: #2dd4bf; margin-bottom: 20px; text-transform: uppercase; letter-spacing: 1.5px;}
.about-hero h1 { font-size: 40px; font-weight: 900; letter-spacing: 1px; margin-bottom: 18px; background: linear-gradient(to right, #fff, #94a3b8); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.about-hero p { font-size: 15px; color: #94a3b8; font-weight: 500; line-height: 1.8; }

.section-title-wrap { display: flex; align-items: center; gap: 14px; margin-bottom: 28px; }
.section-title-wrap i { font-size: 22px; color: var(--primary); }
.section-title { font-size: 24px; font-weight: 900; color: var(--text-dark); }

.core-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 50px; }
.core-card {
    background: rgba(255, 255, 255, 0.95); border: 1px solid rgba(255,255,255,1);
    padding: 36px 30px; border-radius: var(--radius-main); box-shadow: var(--shadow-soft);
    transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.core-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); border-color: rgba(13,148,136,0.3); }
.core-icon {
    width: 56px; height: 56px; border-radius: 18px; display: flex; align-items: center; justify-content: center;
    font-size: 22px; margin-bottom: 24px; color: #fff;
}
.core-card:nth-child(1) .core-icon { background: linear-gradient(135deg, #2dd4bf, #0d9488); box-shadow: 0 8px 20px rgba(13,148,136,0.25); }
.core-card:nth-child(2) .core-icon { background: linear-gradient(135deg, #f97316, #ea580c); box-shadow: 0 8px 20px rgba(249,115,22,0.25); }
.core-card:nth-child(3) .core-icon { background: linear-gradient(135deg, #3b82f6, #1d4ed8); box-shadow: 0 8px 20px rgba(59,130,246,0.25); }

.core-h3 { font-size: 19px; font-weight: 900; color: var(--text-dark); margin-bottom: 12px; }
.core-p { font-size: 14px; color: var(--text-sub); line-height: 1.7; font-weight: 500; }

.eco-section { display: grid; grid-template-columns: 1.3fr 1fr; gap: 30px; margin-bottom: 50px; }
.eco-main-card {
    background: rgba(255, 255, 255, 0.95); border: 1px solid rgba(255,255,255,1);
    border-radius: var(--radius-main); padding: 40px; box-shadow: var(--shadow-soft);
    display: flex; flex-direction: column; justify-content: space-between;
}
.eco-row { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-top: 30px; }
.eco-item { background: var(--bg-body); padding: 20px; border-radius: 16px; border: 1px solid transparent; transition: 0.3s; }
.eco-item:hover { background: #fff; border-color: rgba(13,148,136,0.2); transform: scale(1.02); }
.eco-item-title { font-weight: 800; color: var(--text-dark); font-size: 15px; margin-bottom: 6px; display: flex; align-items: center; gap: 8px; }
.eco-item-title i { color: var(--primary); }
.eco-item-desc { font-size: 13px; color: var(--text-sub); line-height: 1.6; font-weight: 500; }

.timeline-box {
    background: rgba(255, 255, 255, 0.95); border: 1px solid rgba(255,255,255,1);
    border-radius: var(--radius-main); padding: 40px; box-shadow: var(--shadow-soft);
}
.timeline-container { position: relative; padding-left: 30px; }
.timeline-container::before { content: ''; position: absolute; left: 6px; top: 10px; bottom: 10px; width: 2px; background: #e2e8f0; }
.timeline-node { position: relative; margin-bottom: 24px; }
.timeline-node:last-child { margin-bottom: 0; }
.timeline-dot { position: absolute; left: -30px; top: 8px; width: 14px; height: 14px; background: #fff; border: 3px solid var(--primary); border-radius: 50%; z-index: 2; transition: 0.3s; }
.timeline-node:hover .timeline-dot { background: var(--primary); transform: scale(1.2); box-shadow: 0 0 10px rgba(13, 148, 136, 0.4); }
.timeline-date { font-size: 14px; font-weight: 800; color: var(--primary); margin-bottom: 2px; }
.timeline-h4 { font-size: 16px; font-weight: 900; color: var(--text-dark); margin-bottom: 4px; }
.timeline-desc { font-size: 13px; color: var(--text-sub); font-weight: 500; }

/* 页脚 */
.site-footer {
    background-color: #0f172a; color: #94a3b8; padding: 60px 40px 25px; border-radius: var(--radius-main);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1); border: 1px solid rgba(255,255,255,0.05); position: relative; overflow: hidden;
    margin-top: 40px;
}
.site-footer::before { content: ''; position: absolute; top:0; left: 0; width: 100%; height: 4px; background: linear-gradient(90deg, var(--primary), #3b82f6); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 40px; margin: 0 auto 40px; max-width: 900px; }
.footer-col h4 { color: #f8fafc; font-size: 16px; font-weight: 900; margin-bottom: 25px; position: relative; letter-spacing: 1px; }
.footer-col h4::after { content: ''; position: absolute; left: 0; bottom: -10px; width: 30px; height: 3px; background: var(--primary); border-radius: 2px; }
.footer-logo { display: flex; align-items: center; gap: 12px; color: #fff; font-size: 24px; font-weight: 900; margin-bottom: 20px; }
.footer-logo i { color: var(--primary); font-size: 30px; text-shadow: 0 0 15px rgba(13, 148, 136, 0.5);}
.footer-desc { line-height: 1.8; font-size: 14px; margin-bottom: 25px; color: #94a3b8; font-weight: 500; }
.footer-links { display: flex; flex-direction: column; gap: 14px; }
.footer-links a { color: #94a3b8; font-size: 14px; font-weight: 600; display: flex; align-items: center; gap: 8px; }
.footer-links a::before { content: '›'; color: var(--primary); font-size: 18px; font-weight: bold; opacity: 0; transform: translateX(-5px); transition: 0.3s; }
.footer-links a:hover { color: #fff; } .footer-links a:hover::before { opacity: 1; transform: translateX(0); }
.footer-bottom { text-align: center; padding-top: 25px; border-top: 1px solid rgba(255,255,255,0.05); font-size: 13px; font-weight: 500; color: #64748b; }
.footer-bottom span { color: rgba(255,255,255,0.1); margin: 0 10px; }

/* 回到顶部按钮 */
.back-to-top {
    position: fixed; bottom: 40px; right: 40px; width: 52px; height: 52px;
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center;
    font-size: 22px; box-shadow: 0 10px 25px rgba(13, 148, 136, 0.4);
    cursor: pointer; z-index: 1000; opacity: 0; visibility: hidden;
    transform: translateY(20px); transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.back-to-top.show { opacity: 1; visibility: visible; transform: translateY(0); }

/* ================= 响应式媒体查询 ================= */
@media (max-width: 1200px) {
    .core-grid { grid-template-columns: repeat(2, 1fr); }
    .eco-section { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
    .core-grid { grid-template-columns: 1fr; }
    .about-hero { padding: 40px; }
}