/* ===== 全局重置与基础 ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
html {
    scroll-behavior: smooth;
    font-size: 16px;
}
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
    line-height: 1.6;
    color: #1a1a2e;
    background: #f8f9fa;
    transition: background 0.3s, color 0.3s;
    overflow-x: hidden;
}
a {
    color: #2c3e50;
    text-decoration: none;
    transition: color 0.2s;
}
a:hover {
    color: #e67e22;
}
img {
    max-width: 100%;
    height: auto;
    display: block;
}
ul, ol {
    list-style: none;
    padding-left: 0;
}
h1, h2, h3, h4 {
    line-height: 1.3;
    font-weight: 700;
}

/* ===== 暗色模式 ===== */
@media (prefers-color-scheme: dark) {
    body {
        background: #0f0f1a;
        color: #e0e0e0;
    }
    a {
        color: #a0c4ff;
    }
    a:hover {
        color: #f0c27f;
    }
    header, footer, section, .card, article, nav {
        background: rgba(20, 20, 35, 0.85) !important;
        backdrop-filter: blur(12px) !important;
        border-color: rgba(255, 255, 255, 0.08) !important;
    }
    .glass, .card, section, article, nav, footer, header {
        background: rgba(25, 25, 45, 0.7) !important;
        backdrop-filter: blur(14px) !important;
        border: 1px solid rgba(255, 255, 255, 0.06);
    }
    input, button, textarea {
        background: #1e1e32;
        color: #e0e0e0;
        border-color: #333;
    }
    button {
        background: #2c3e50;
        color: #f0f0f0;
    }
    button:hover {
        background: #e67e22;
    }
}

/* ===== 通用组件 ===== */
.glass {
    background: rgba(255, 255, 255, 0.6);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 1.5rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.glass:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

.card {
    background: #ffffff;
    border-radius: 24px;
    padding: 1.8rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
    transition: all 0.3s cubic-bezier(0.23, 1, 0.32, 1);
    border: 1px solid rgba(0, 0, 0, 0.02);
}
.card:hover {
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.08);
    transform: translateY(-6px) scale(1.01);
}

section {
    padding: 2.5rem 1.2rem;
    margin: 1.5rem auto;
    max-width: 1200px;
    border-radius: 28px;
    background: rgba(255, 255, 255, 0.5);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards;
}
section:nth-child(2) { animation-delay: 0.1s; }
section:nth-child(3) { animation-delay: 0.2s; }
section:nth-child(4) { animation-delay: 0.3s; }
section:nth-child(5) { animation-delay: 0.4s; }
section:nth-child(6) { animation-delay: 0.5s; }
section:nth-child(7) { animation-delay: 0.6s; }
section:nth-child(8) { animation-delay: 0.7s; }
section:nth-child(9) { animation-delay: 0.8s; }
section:nth-child(10) { animation-delay: 0.9s; }

@keyframes fadeUp {
    0% { opacity: 0; transform: translateY(30px); }
    100% { opacity: 1; transform: translateY(0); }
}

h1 {
    font-size: 2.4rem;
    background: linear-gradient(135deg, #2c3e50, #e67e22, #f39c12);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
}
h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    position: relative;
    display: inline-block;
}
h2::after {
    content: '';
    display: block;
    width: 60%;
    height: 4px;
    background: linear-gradient(90deg, #e67e22, #f1c40f);
    border-radius: 4px;
    margin-top: 0.5rem;
}
h3 {
    font-size: 1.4rem;
    margin-top: 1.2rem;
    margin-bottom: 0.6rem;
    color: #2c3e50;
}
p {
    margin-bottom: 1rem;
    font-size: 1.05rem;
}

/* ===== 渐变Banner（首屏） ===== */
section:first-of-type {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 30%, #e67e22 70%, #f39c12 100%);
    color: white;
    text-align: center;
    padding: 4rem 1.5rem;
    border-radius: 0 0 40px 40px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
    position: relative;
    overflow: hidden;
    border: none;
}
section:first-of-type::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(255,255,255,0.08), transparent 60%);
    pointer-events: none;
}
section:first-of-type h1 {
    background: none;
    -webkit-text-fill-color: white;
    color: white;
    font-size: 2.8rem;
    text-shadow: 0 4px 12px rgba(0,0,0,0.2);
}
section:first-of-type p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 1rem auto;
    opacity: 0.9;
}
section:first-of-type strong {
    color: #f1c40f;
}

/* ===== Header / Nav ===== */
header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.04);
    padding: 0.5rem 1.2rem;
}
nav {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    gap: 0.8rem;
}
nav ul {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem 1.5rem;
    flex: 1 1 auto;
    justify-content: center;
}
nav ul li a {
    font-weight: 600;
    padding: 0.3rem 0.2rem;
    position: relative;
    transition: color 0.2s;
}
nav ul li a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: #e67e22;
    transition: width 0.3s ease;
}
nav ul li a:hover::after {
    width: 100%;
}
nav form {
    display: flex;
    gap: 0.4rem;
}
nav input {
    padding: 0.5rem 1rem;
    border-radius: 40px;
    border: 1px solid #ddd;
    background: rgba(255,255,255,0.5);
    backdrop-filter: blur(4px);
    min-width: 160px;
    font-size: 0.95rem;
    transition: all 0.2s;
}
nav input:focus {
    outline: none;
    border-color: #e67e22;
    box-shadow: 0 0 0 3px rgba(230, 126, 34, 0.15);
}
nav button {
    padding: 0.5rem 1.2rem;
    border-radius: 40px;
    border: none;
    background: #2c3e50;
    color: white;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s, transform 0.1s;
}
nav button:hover {
    background: #e67e22;
    transform: scale(1.05);
}

/* ===== 新闻文章卡片 ===== */
#news article {
    background: rgba(255, 255, 255, 0.5);
    backdrop-filter: blur(8px);
    padding: 1.5rem;
    border-radius: 20px;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s ease;
}
#news article:hover {
    background: rgba(255, 255, 255, 0.7);
    transform: translateX(6px) scale(1.01);
    box-shadow: 0 8px 30px rgba(0,0,0,0.05);
}
#news article a {
    display: inline-block;
    margin-top: 0.8rem;
    padding: 0.4rem 1.2rem;
    background: #2c3e50;
    color: white;
    border-radius: 40px;
    font-weight: 500;
    transition: all 0.2s;
}
#news article a:hover {
    background: #e67e22;
    transform: translateY(-2px);
}

/* ===== FAQ 手风琴效果 ===== */
#faq div {
    background: rgba(255, 255, 255, 0.4);
    backdrop-filter: blur(6px);
    border-radius: 16px;
    padding: 1rem 1.5rem;
    margin-bottom: 0.8rem;
    border: 1px solid rgba(255, 255, 255, 0.15);
    transition: all 0.25s;
    cursor: pointer;
}
#faq div:hover {
    background: rgba(255, 255, 255, 0.6);
    transform: scale(1.01);
}
#faq h3 {
    margin: 0;
    font-size: 1.15rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
#faq h3::after {
    content: '+';
    font-size: 1.6rem;
    font-weight: 300;
    color: #e67e22;
    transition: transform 0.3s;
}
#faq div.active h3::after,
#faq div:hover h3::after {
    transform: rotate(45deg);
}
#faq p {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, margin 0.3s;
    margin: 0;
    color: #555;
}
#faq div.active p,
#faq div:hover p {
    max-height: 300px;
    margin-top: 0.8rem;
}

/* ===== 客户评价 / 案例 ===== */
#cases h3, #cases p {
    padding-left: 1rem;
    border-left: 4px solid #e67e22;
    margin-bottom: 1.2rem;
}

/* ===== 联系我们 ===== */
#contact p {
    display: flex;
    align-items: center;
    gap: 0.6rem;
}
#contact p::before {
    content: '•';
    color: #e67e22;
    font-size: 1.8rem;
    line-height: 1;
}

/* ===== Footer ===== */
footer {
    background: rgba(44, 62, 80, 0.9);
    backdrop-filter: blur(12px);
    color: #ecf0f1;
    padding: 2.5rem 1.5rem;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,0.1);
    margin-top: 3rem;
}
footer p {
    margin-bottom: 0.6rem;
    font-size: 0.95rem;
    opacity: 0.85;
}
footer a {
    color: #f1c40f;
    text-decoration: underline;
}

/* ===== 网站地图 & 友情链接 ===== */
section ul {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem 2rem;
    margin-top: 1rem;
}
section ul li a {
    padding: 0.3rem 0.8rem;
    background: rgba(255,255,255,0.3);
    border-radius: 40px;
    transition: all 0.2s;
    font-weight: 500;
}
section ul li a:hover {
    background: #e67e22;
    color: white;
    transform: translateY(-2px);
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    html { font-size: 15px; }
    h1 { font-size: 2rem; }
    h2 { font-size: 1.6rem; }
    section { padding: 1.5rem 1rem; margin: 1rem; border-radius: 20px; }
    section:first-of-type { padding: 2.5rem 1rem; }
    nav { flex-direction: column; align-items: stretch; }
    nav ul { justify-content: center; gap: 0.6rem 1rem; }
    nav form { width: 100%; }
    nav input { flex: 1; min-width: 0; }
    nav button { flex-shrink: 0; }
    #news article { padding: 1rem; }
    #faq div { padding: 0.8rem 1rem; }
    footer { padding: 1.5rem 1rem; }
}
@media (max-width: 480px) {
    html { font-size: 14px; }
    h1 { font-size: 1.8rem; }
    nav ul { gap: 0.4rem 0.8rem; }
    nav ul li a { font-size: 0.9rem; }
}

/* ===== 辅助滚动动画（Intersection Observer 配合） ===== */
@media (prefers-reduced-motion: no-preference) {
    section {
        opacity: 0;
        animation: fadeUp 0.7s ease forwards;
    }
}

/* ===== 自定义滚动条 ===== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: #f0f0f0;
    border-radius: 10px;
}
::-webkit-scrollbar-thumb {
    background: #b0b0b0;
    border-radius: 10px;
}
::-webkit-scrollbar-thumb:hover {
    background: #888;
}