:root {
    --bg-light: #ffffff;
    --bg-alt: #f8fafc;
    --surface: #ffffff;
    --accent: #0066FF;
    --accent-soft: rgba(0, 102, 255, 0.08);
    --text-main: #0f172a;
    --text-muted: #64748b;
    --glass: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.05);
    --card-shadow: 0 10px 30px rgba(0, 0, 0, 0.03);
    --card-shadow-hover: 0 25px 50px rgba(0, 102, 255, 0.1);
}

body {
    background-color: var(--bg-light);
    color: var(--text-main);
    font-family: 'Inter', "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.7;
    overflow-x: hidden;
}

/* 导航栏优化 */
.navbar {
    padding: 1.25rem 0;
    transition: all 0.3s;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
}

.navbar.scrolled {
    padding: 0.75rem 0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.navbar-brand img {
    max-height: 45px;
    width: auto;
    object-fit: contain;
    background: transparent !important;
}

/* 英雄首屏字体与布局 */
.hero-section {
    padding-top: 160px; /* 增加顶部间距，不与菜单栏平齐 */
    padding-bottom: 100px;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4rem); /* 更大的字体 */
    font-weight: 850;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.lead {
    font-size: 1.35rem; /* 更大的字体 */
    font-weight: 400;
}

/* 渐变文本 */
.text-gradient {
    background: linear-gradient(135deg, #0f172a 0%, #0066FF 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Section 样式 */
.section-title {
    font-size: clamp(2rem, 5vw, 2.5rem);
    font-weight: 800;
    margin-bottom: 3.5rem;
    text-align: center;
}

.section-subtitle {
    display: block;
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    margin-bottom: 1rem;
    text-align: center;
}

/* 布局网格系统 */
.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}

.grid-6 {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 1.5rem;
}

/* 卡片通用样式 */
.tech-card {
    background: var(--surface);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 2.25rem;
    transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    height: 100%;
    position: relative;
    display: flex;
    flex-direction: column;
}

.tech-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--card-shadow-hover);
    border-color: rgba(0, 102, 255, 0.1);
}

/* 多彩图标容器 */
.icon-box-colorful {
    width: 64px;
    height: 64px;
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    transition: 0.4s;
}

/* 合作伙伴网格 */
.partners-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 1.5rem;
}

.partner-item {
    background: #fff;
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 1.5rem 1rem;
    text-align: center;
    transition: all 0.3s;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

/* 轮播图优化 */
.hero-carousel .carousel-item img {
    border-radius: 32px;
    height: 520px;
    object-fit: cover;
    box-shadow: 0 30px 60px rgba(0,0,0,0.15);
}

/* 项目案例卡片 */
.case-card {
    border-radius: 24px;
    overflow: hidden;
    background: #fff;
    border: 1px solid var(--glass-border);
    transition: all 0.5s;
    height: 100%;
}

.case-image-wrapper {
    position: relative;
    height: 240px;
    overflow: hidden;
}

.case-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: 0.8s;
}

/* 悬浮按钮 */
.floating-controls {
    position: fixed;
    right: 30px;
    bottom: 30px;
    display: flex;
    flex-direction: column;
    gap: 15px;
    z-index: 9999;
}

.float-btn {
    width: 55px;
    height: 55px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
    transition: 0.3s;
    text-decoration: none;
    cursor: pointer;
    border: none;
}

.float-btn-tg { background: #229ED9; }
.float-btn-up { background: var(--accent); opacity: 0; visibility: hidden; }
.float-btn-up.visible { opacity: 1; visibility: visible; }

.float-btn:hover {
    transform: scale(1.1) translateY(-5px);
    color: white;
}

/* 底部按钮字体突出 */
.footer-cta .btn {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: 1px;
    padding: 1.25rem 2.5rem;
}

/* 响应式调整 */
@media (max-width: 1200px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-6 { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 992px) {
    .partners-grid { grid-template-columns: repeat(3, 1fr); }
    .hero-carousel .carousel-item img { height: 400px; }
    .hero-section { padding-top: 120px; }
}

@media (max-width: 768px) {
    .grid-4, .grid-6 { grid-template-columns: 1fr; }
    .hero-title { font-size: 2.2rem; }
}