/* =============== RESET & GLOBAL =============== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

/* =============== HERO CAROUSEL =============== */
.hero-carousel {
    position: relative;
    height: 900px;
    width: 100%;
    overflow: hidden;
}

/* Embedded Header inside Carousel */
.hero-header {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
}

/* Scrolled state: solid fixed header */
.hero-header.scrolled {
    position: fixed;
    top: 0;
    background-color: #002244;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    padding: 0.8rem 2rem;
}

.logo {
    background-color: #ffffff; /* 白色背景 */
    color: #d35400;             /* 橙色文字 */
    font-size: 1.8rem;
    font-weight: bold;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    /* 移除以下两行：不再需要边框和阴影 */
 /*   border: none !important;
    box-shadow: none !important;*/
    display: inline-block;
    margin-right: 2rem;
}

.logo:hover {
    transform: scale(1.02);
}

nav a,
.dropbtn {
    color: white;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    margin-left: 1.5rem;
    transition: color 0.2s;
}

nav a:hover {
    color: #d35400;
}

/* =============== DROPDOWN MENU =============== */
.dropdown {
    position: relative;
    display: inline-block;
}

.dropbtn {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 4px;
}

.dropbtn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.dropdown-content {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background-color: #002244;
    min-width: 200px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    z-index: 1001;
    border-radius: 4px;
    overflow: hidden;
}

.dropdown-content a {
    color: white;
    padding: 0.8rem 1rem;
    text-decoration: none;
    display: block;
    transition: background-color 0.2s;
    font-size: 0.95rem;
}

.dropdown-content a:hover {
    background-color: #003366;
    color: #d35400;
}

.dropdown:hover .dropdown-content {
    display: block;
}

/* =============== HERO SLIDE =============== */
.hero-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

.hero-slide.active {
    opacity: 1;
}

.hero-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.hero-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 10;
    color: white;
    font-size: 2.8rem;
    text-align: center;
    max-width: 800px;
    padding: 0 1rem;
    text-shadow: 2px 2px 5px rgba(0, 0, 0, 0.7);
    font-weight: 600;
    letter-spacing: 0.5px;
}

/* =============== MAIN CONTENT =============== */
.main-container {
    max-width: 1100px;
    margin: 3rem auto;
    padding: 0 2rem;
}

.intro-text {
    text-align: center;
    margin-bottom: 2.5rem;
    font-size: 1.1rem;
    color: #444;
}

.features {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    justify-content: center;
    margin: 2.5rem 0;
}

.feature-card {
    background: white;
    border: 1px solid #eee;
    padding: 1.2rem;
    border-radius: 8px;
    flex: 1;
    min-width: 220px;
    max-width: 300px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.2s;
}

.feature-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.feature-card h3 {
    color: #003366;
    margin-bottom: 0.6rem;
    font-size: 1.2rem;
}

h2 {
    text-align: center;
    margin: 2rem 0;
    color: #003366;
    font-size: 1.8rem;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.service-item {
    background: white;
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
    text-align: center;
    transition: transform 0.2s;
    text-decoration: none;
    color: inherit;
}

.service-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.1);
}

.service-item h3 {
    color: #003366;
    margin-bottom: 0.6rem;
}

.cta-section {
    background: linear-gradient(to right, #003366, #002244);
    color: white;
    padding: 2.5rem;
    border-radius: 12px;
    margin-top: 2rem;
    text-align: center;
}

.cta-section h3 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
}

.submit-btn {
    background: #d35400;
    color: white;
    border: none;
    padding: 0.8rem 1.8rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    margin-top: 1rem;
}

.submit-btn:hover {
    background: #b04600;
}

/* =============== FOOTER =============== */
footer {
    background: #002244;
    color: white;
    padding: 2rem;
    margin-top: 3rem;
    text-align: center;
    font-size: 0.95rem;
}

footer p {
    margin-bottom: 0.6rem;
}

footer a {
    color: #ddd;
    text-decoration: underline;
}

/* =============== RESPONSIVE =============== */
@media (max-width: 768px) {
    .hero-carousel {
        height: 450px;
    }

    .hero-text {
        font-size: 1.8rem;
        text-shadow: 1px 1px 4px rgba(0, 0, 0, 0.8);
    }

    .hero-header {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem;
        background-color: rgba(0, 0, 0, 0.7);
    }

    .hero-header.scrolled {
        padding: 0.8rem 1rem;
    }

    .hero-header nav {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.8rem;
        width: 100%;
    }

    .logo {
        text-align: center;
        width: 100%;
    }

    nav a,
    .dropbtn {
        margin: 0 0.5rem;
    }

    .feature-card,
    .service-item {
        min-width: 100%;
    }

    .cta-section {
        padding: 1.5rem;
    }
}
/* ========== 导航栏全局重置：白底 + 蓝字 ========== */

.hero-header {
  background-color: #ffffff !important; /* 强制白底 */
  color: #002244;
  box-shadow: none; /* 初始无阴影 */
  padding: 1rem 5%;
  transition: box-shadow 0.3s ease;
}

/* LOGO 和链接文字颜色 */
.hero-header .logo,
.hero-header nav a,
.hero-header .dropbtn {
  color: #002244 !important;
  text-decoration: none;
}

/* 滚动后增加 subtle 阴影，提升层次（可选） */
.hero-header.scrolled {
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
  /* 背景仍为白色，无需 change */
}

/* 下拉菜单样式 */
.dropdown-content {
  background-color: #ffffff;
  border: 1px solid #e0e0e0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.dropdown-content a {
  color: #002244 !important;
}

.dropdown-content a:hover {
  background-color: #f5f7fa; /* 浅灰蓝悬停 */
  color: #d35400 !important; /* 橙色强调（保留品牌感） */
}\

/* 移动端汉堡菜单（如有）也需同步 */
@media (max-width: 768px) {
  .hero-header {
    background-color: #ffffff;
  }

  .mobile-menu a {
    color: #002244;
  }

  .mobile-menu a:hover {
    background-color: #f5f7fa;
    color: #d35400;
  }
}