/* Reset & Base */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: "Microsoft YaHei", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
    color: #1f2937;
    background: #f8fafc;
    line-height: 1.6;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.site-header {
    background: linear-gradient(135deg, #0b1220 0%, #1e3a5f 100%);
    color: #fff;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 12px rgba(0,0,0,0.15);
    backdrop-filter: blur(10px);
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}
.logo-container {
    display: flex;
    align-items: center;
    gap: 12px;
}
.logo-img {
    height: 45px;
    width: auto;
    object-fit: contain;
}
.logo-text {
    color: #fff;
    font-size: 1.3rem;
    font-weight: 700;
    text-decoration: none;
    letter-spacing: 0.5px;
    transition: opacity 0.2s;
}
.logo-text:hover {
    opacity: 0.9;
}
.main-nav {
    display: flex;
    gap: 32px;
}
.main-nav a {
    color: #e5e7eb;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s;
    padding: 8px 0;
    position: relative;
}
.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: #60a5fa;
    transition: width 0.3s;
}
.main-nav a:hover { 
    color: #60a5fa;
}
.main-nav a:hover::after {
    width: 100%;
}
.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 1.6rem;
    cursor: pointer;
    padding: 8px;
    transition: transform 0.2s;
}
.menu-toggle:hover {
    transform: scale(1.1);
}

/* Hero Section with Background */
.hero {
    position: relative;
    background: url('../images/background.jpg') center center / cover no-repeat;
    color: #fff;
    padding: 140px 0 120px;
    text-align: center;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(11, 18, 32, 0.65);
    z-index: 1;
}
.hero .container {
    position: relative;
    z-index: 2;
}
.hero h1 {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 20px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
    text-shadow: 0 2px 8px rgba(0,0,0,0.3);
    line-height: 1.3;
}
.hero p {
    font-size: 1.2rem;
    color: #e0e7ff;
    max-width: 720px;
    margin: 0 auto 32px;
    text-shadow: 0 1px 4px rgba(0,0,0,0.2);
}

/* Banner */
.banner-section {
    position: relative;
    width: 100%;
    height: 400px;
    overflow: hidden;
}
.banner-section img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}
.banner-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to bottom, rgba(11, 18, 32, 0.3), rgba(11, 18, 32, 0.5));
    display: flex;
    align-items: center;
    justify-content: center;
}
.banner-content {
    text-align: center;
    color: #fff;
    padding: 0 24px;
}
.banner-content h2 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 12px;
    text-shadow: 0 2px 6px rgba(0,0,0,0.4);
}
.banner-content p {
    font-size: 1.1rem;
    color: #e0e7ff;
    text-shadow: 0 1px 4px rgba(0,0,0,0.3);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 14px 32px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s;
    border: 2px solid transparent;
}
.btn-primary {
    background: #2563eb;
    color: #fff;
    box-shadow: 0 4px 14px rgba(37,99,235,0.35);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(37,99,235,0.5);
    background: #1d4ed8;
}

/* Page Header */
.page-header {
    background: linear-gradient(135deg, #0b1220 0%, #1e3a5f 100%);
    color: #fff;
    padding: 80px 0 70px;
    text-align: center;
    position: relative;
}
.page-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('../images/background.jpg') center center / cover no-repeat;
    opacity: 0.15;
}
.page-header .container {
    position: relative;
    z-index: 1;
}
.page-header h1 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 12px;
    text-shadow: 0 2px 6px rgba(0,0,0,0.3);
}
.page-header p {
    color: #cbd5e1;
    font-size: 1.1rem;
}

/* Section */
.section { 
    padding: 72px 0;
}
.section-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: #0f172a;
    position: relative;
}
.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: linear-gradient(to right, #2563eb, #60a5fa);
    margin: 16px auto 0;
    border-radius: 2px;
}
.section-subtitle {
    text-align: center;
    color: #475569;
    max-width: 760px;
    margin: 0 auto 48px;
    font-size: 1.08rem;
    line-height: 1.8;
}

/* Grid */
.grid {
    display: grid;
    gap: 28px;
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }

/* Card */
.card {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    transition: all 0.3s;
    border: 1px solid #e5e7eb;
}
.card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 32px rgba(0,0,0,0.12);
    border-color: #60a5fa;
}
.card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 14px;
    color: #0f172a;
    position: relative;
    padding-bottom: 12px;
}
.card h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 3px;
    background: linear-gradient(to right, #2563eb, #60a5fa);
    border-radius: 2px;
}
.card p {
    color: #475569;
    font-size: 1rem;
    line-height: 1.8;
}

/* Contact Placeholder */
.contact-placeholder {
    background: #fff;
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    max-width: 650px;
    margin: 0 auto;
    text-align: left;
    border: 1px solid #e5e7eb;
}
.contact-placeholder p {
    margin-bottom: 16px;
    color: #334155;
    font-size: 1.05rem;
    line-height: 1.8;
    padding: 12px 16px;
    background: #f8fafc;
    border-radius: 8px;
    border-left: 4px solid #2563eb;
}
.contact-placeholder p strong {
    color: #0f172a;
    display: inline-block;
    min-width: 120px;
}

/* Footer */
.site-footer {
    background: linear-gradient(135deg, #0b1220 0%, #1e3a5f 100%);
    color: #94a3b8;
    text-align: center;
    padding: 32px 0;
    font-size: 0.95rem;
    border-top: 3px solid #2563eb;
}
.site-footer p {
    margin: 0;
}

/* Responsive */
@media (max-width: 900px) {
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
    .hero h1 { font-size: 2.2rem; }
    .banner-section { height: 300px; }
    .banner-content h2 { font-size: 1.8rem; }
}
@media (max-width: 700px) {
    .main-nav {
        display: none;
        position: absolute;
        top: 72px;
        left: 0; right: 0;
        background: #0b1220;
        flex-direction: column;
        padding: 20px 24px;
        gap: 16px;
        box-shadow: 0 8px 16px rgba(0,0,0,0.15);
    }
    .main-nav.open { display: flex; }
    .menu-toggle { display: block; }
    .hero { padding: 100px 0 80px; }
    .hero h1 { font-size: 1.8rem; }
    .hero p { font-size: 1.05rem; }
    .grid-2, .grid-3 { grid-template-columns: 1fr; }
    .section { padding: 52px 0; }
    .section-title { font-size: 1.7rem; }
    .page-header { padding: 60px 0 50px; }
    .page-header h1 { font-size: 1.8rem; }
    .banner-section { height: 250px; }
    .banner-content h2 { font-size: 1.5rem; }
    .logo-text { font-size: 1.1rem; }
    .logo-img { height: 38px; }
}