/* ============================================
   北京尧图网络科技有限公司 - 全局样式
   数码复古风 | 银灰 + 深黑 + 浅棕
   ============================================ */

/* CSS Reset & 基础变量 */
:root {
    --color-silver: #C0C0C0;
    --color-dark-gray: #2C2C2C;
    --color-deep-black: #1A1A1A;
    --color-light-brown: #D2B48C;
    --color-brown-accent: #8B7355;
    --color-text-light: #F5F5F5;
    --color-text-muted: #999999;
    --font-primary: 'Segoe UI', 'Microsoft YaHei', sans-serif;
    --font-mono: 'Courier New', monospace;
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 8px 30px rgba(210, 180, 140, 0.2);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    background-color: var(--color-deep-black);
    color: var(--color-text-light);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-smooth);
}

ul, ol {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ============================================
   顶部固定导航栏
   ============================================ */
.header-fixed {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: linear-gradient(180deg, rgba(26, 26, 26, 0.98) 0%, rgba(44, 44, 44, 0.95) 100%);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(192, 192, 192, 0.1);
    transition: var(--transition-smooth);
}

.header-fixed.scrolled {
    background: linear-gradient(180deg, rgba(26, 26, 26, 1) 0%, rgba(44, 44, 44, 1) 100%);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.5);
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo img {
    height: 50px;
    width: auto;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-light-brown);
    letter-spacing: 2px;
}

.logo-text span {
    color: var(--color-silver);
    font-size: 0.9rem;
    display: block;
    font-weight: 400;
}

.nav-menu {
    display: flex;
    gap: 35px;
}

.nav-menu a {
    font-size: 0.95rem;
    color: var(--color-text-light);
    position: relative;
    padding: 8px 0;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-light-brown);
    transition: var(--transition-smooth);
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--color-light-brown);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 10px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--color-light-brown);
    transition: var(--transition-smooth);
}

/* ============================================
   不规则网格叠加布局容器
   ============================================ */
.main-content {
    padding-top: 80px;
    min-height: 100vh;
}

.grid-overlay-container {
    position: relative;
    max-width: 1400px;
    margin: 0 auto;
    padding: 60px 40px;
}

/* 背景装饰网格 */
.bg-grid-pattern {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    height: calc(100vh - 80px);
    background-image: 
        linear-gradient(rgba(192, 192, 192, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(192, 192, 192, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    z-index: -1;
}

/* ============================================
   全屏 Banner 区域
   ============================================ */
.hero-banner {
    position: relative;
    height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    margin-bottom: 80px;
}

.hero-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(ellipse at center, rgba(210, 180, 140, 0.1) 0%, rgba(26, 26, 26, 0.8) 100%);
    z-index: 1;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.4;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 900px;
    padding: 0 20px;
}

.hero-title {
    font-size: 4rem;
    font-weight: 800;
    color: var(--color-text-light);
    margin-bottom: 20px;
    letter-spacing: 5px;
    text-shadow: 0 0 30px rgba(210, 180, 140, 0.3);
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 1s ease forwards 0.3s;
}

.hero-subtitle {
    font-size: 1.3rem;
    color: var(--color-light-brown);
    margin-bottom: 40px;
    font-weight: 300;
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 1s ease forwards 0.6s;
}

.hero-cta {
    display: inline-flex;
    gap: 20px;
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 1s ease forwards 0.9s;
}

.btn {
    padding: 15px 40px;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: var(--transition-smooth);
    text-transform: uppercase;
    letter-spacing: 2px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-light-brown) 0%, var(--color-brown-accent) 100%);
    color: var(--color-deep-black);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(210, 180, 140, 0.4);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--color-light-brown);
    color: var(--color-light-brown);
}

.btn-outline:hover {
    background: var(--color-light-brown);
    color: var(--color-deep-black);
}

/* ============================================
   核心优势板块 - 不规则卡片布局
   ============================================ */
.features-section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 2.5rem;
    color: var(--color-light-brown);
    margin-bottom: 15px;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: var(--color-silver);
}

.section-desc {
    color: var(--color-text-muted);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    grid-auto-flow: dense;
}

.feature-card {
    background: linear-gradient(145deg, rgba(44, 44, 44, 0.8) 0%, rgba(26, 26, 26, 0.9) 100%);
    border: 1px solid rgba(192, 192, 192, 0.1);
    border-radius: 0;
    padding: 40px;
    position: relative;
    overflow: hidden;
    transition: var(--transition-smooth);
    clip-path: polygon(0 0, 100% 0, 100% 85%, 85% 100%, 0 100%);
}

.feature-card:nth-child(2n) {
    clip-path: polygon(0 0, 100% 0, 100% 100%, 15% 100%, 0 85%);
}

.feature-card:nth-child(3n) {
    grid-column: span 2;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
    border-color: var(--color-light-brown);
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--color-light-brown), var(--color-silver));
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition-smooth);
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 70px;
    height: 70px;
    margin-bottom: 25px;
    object-fit: contain;
}

.feature-title {
    font-size: 1.4rem;
    color: var(--color-text-light);
    margin-bottom: 15px;
}

.feature-text {
    color: var(--color-text-muted);
    line-height: 1.8;
}

/* ============================================
   快速入口板块
   ============================================ */
.quick-access {
    padding: 80px 0;
    background: linear-gradient(180deg, rgba(44, 44, 44, 0.5) 0%, rgba(26, 26, 26, 0.5) 100%);
}

.access-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.access-item {
    position: relative;
    height: 200px;
    overflow: hidden;
    border: 1px solid rgba(192, 192, 192, 0.1);
    transition: var(--transition-smooth);
}

.access-item:hover {
    border-color: var(--color-light-brown);
}

.access-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-smooth);
}

.access-item:hover img {
    transform: scale(1.1);
    opacity: 0.3;
}

.access-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 20px;
    background: linear-gradient(transparent, rgba(26, 26, 26, 0.95));
}

.access-title {
    color: var(--color-light-brown);
    font-size: 1.2rem;
    font-weight: 600;
}

/* ============================================
   资讯列表板块
   ============================================ */
.news-section {
    padding: 80px 0;
}

.news-tabs {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 40px;
}

.news-tab {
    padding: 10px 25px;
    border: 1px solid rgba(192, 192, 192, 0.2);
    color: var(--color-text-muted);
    cursor: pointer;
    transition: var(--transition-smooth);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.news-tab:hover,
.news-tab.active {
    border-color: var(--color-light-brown);
    color: var(--color-light-brown);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.news-card {
    background: rgba(44, 44, 44, 0.5);
    border: 1px solid rgba(192, 192, 192, 0.1);
    transition: var(--transition-smooth);
    overflow: hidden;
}

.news-card:hover {
    border-color: var(--color-light-brown);
    transform: translateY(-5px);
}

.news-img-wrapper {
    position: relative;
    overflow: hidden;
    height: 200px;
}

.news-img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-smooth);
}

.news-card:hover .news-img-wrapper img {
    transform: scale(1.05);
}

.news-content {
    padding: 25px;
}

.news-date {
    color: var(--color-light-brown);
    font-size: 0.85rem;
    margin-bottom: 10px;
    font-family: var(--font-mono);
}

.news-title {
    font-size: 1.2rem;
    color: var(--color-text-light);
    margin-bottom: 12px;
    line-height: 1.4;
}

.news-excerpt {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ============================================
   统一页脚
   ============================================ */
.site-footer {
    background: linear-gradient(180deg, rgba(26, 26, 26, 1) 0%, rgba(44, 44, 44, 1) 100%);
    border-top: 1px solid rgba(192, 192, 192, 0.1);
    padding: 60px 0 30px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 50px;
    margin-bottom: 40px;
}

.footer-brand h3 {
    color: var(--color-light-brown);
    font-size: 1.5rem;
    margin-bottom: 20px;
}

.footer-brand p {
    color: var(--color-text-muted);
    line-height: 1.8;
    margin-bottom: 20px;
}

.footer-links h4,
.footer-contact h4 {
    color: var(--color-text-light);
    font-size: 1.1rem;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-links h4::after,
.footer-contact h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--color-light-brown);
}

.footer-links ul li {
    margin-bottom: 12px;
}

.footer-links ul li a {
    color: var(--color-text-muted);
    transition: var(--transition-smooth);
}

.footer-links ul li a:hover {
    color: var(--color-light-brown);
    padding-left: 5px;
}

.footer-contact p {
    color: var(--color-text-muted);
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-bottom {
    max-width: 1400px;
    margin: 0 auto;
    padding: 30px 40px 0;
    border-top: 1px solid rgba(192, 192, 192, 0.1);
    text-align: center;
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

/* ============================================
   动画关键帧
   ============================================ */
@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.scroll-reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   响应式设计
   ============================================ */
@media (max-width: 1200px) {
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 992px) {
    .hero-title {
        font-size: 3rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .feature-card:nth-child(3n) {
        grid-column: span 1;
    }
    
    .access-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background: rgba(26, 26, 26, 0.98);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 30px;
        transition: var(--transition-smooth);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hamburger {
        display: flex;
    }
    
    .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(7px, -6px);
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .access-grid {
        grid-template-columns: 1fr;
    }
    
    .grid-overlay-container {
        padding: 40px 20px;
    }
    
    .footer-content,
    .footer-bottom {
        padding-left: 20px;
        padding-right: 20px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.5rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .btn {
        padding: 12px 25px;
        font-size: 0.9rem;
    }
}