/* --- 1. 全局复位与防溢出 --- */
* { 
    box-sizing: border-box; 
    margin: 0; 
    padding: 0; 
}

html, body {
    width: 100%;
    max-width: 100vw;
    overflow-x: hidden;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
    color: #333;
    line-height: 1.6;
    background-color: #f9fafb;
    /* 给顶部固定导航栏留出空间，防止遮挡下方内容 */
    padding-top: 70px; 
}

.container { 
    width: 90%; 
    max-width: 1200px; 
    margin: 0 auto; 
}

.bg-light { 
    background-color: #f8f9fa; 
}

/* ========================================================
   2. 顶部导航栏 (1:1 完美复刻您的目标代码，全显示，无折叠)
======================================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid #e5e7eb;
    padding: 0.6rem 0;
    height: 56px;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
    padding: 0 1rem;
}

.logo {
    font-size: 1.2rem;
    font-weight: 700;
    color: #2563eb;
    text-decoration: none;
    white-space: nowrap;
}

.nav-links {
    display: flex;
    gap: 1.2rem;
    align-items: center;
    /* 允许在极小屏幕下稍微换行，防止挤破屏幕 */
    flex-wrap: wrap; 
    justify-content: flex-end;
}

.nav-links a {
    text-decoration: none;
    color: #1f2937;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.nav-links a:hover {
    color: #2563eb;
}

/* ========================================================
   3. 页面下方原有的内容区块 (一字不改，完全保留您的布局)
======================================================== */
.hero { padding: clamp(40px, 6vw, 60px) 0; }
.hero-content { display: flex; flex-wrap: wrap; align-items: center; gap: 30px; }
.hero-text { flex: 1; min-width: 280px; }
h1 { font-size: clamp(1.8rem, 4vw, 2.5rem); margin-bottom: 15px; line-height: 1.2; }
.subtitle { font-size: 1rem; color: #555; margin-bottom: 10px; }
.hero-buttons { margin-top: 20px; display: flex; flex-wrap: wrap; gap: 15px; }
.btn { padding: 10px 20px; border-radius: 5px; text-decoration: none; font-weight: 500; text-align: center; }
.btn-primary { background-color: #007bff; color: #fff; }
.btn-text { border: 1px solid #007bff; color: #007bff; }
.hero-image { flex: 1; min-width: 280px; }
.images-row { display: flex; gap: 15px; }
.image-wrapper { flex: 1; }
.image-wrapper img { width: 100%; height: auto; border-radius: 8px; box-shadow: 0 4px 6px rgba(0,0,0,0.1); }

.features { padding: clamp(40px, 6vw, 60px) 0; }
.section-title { text-align: center; font-size: clamp(1.5rem, 3vw, 2rem); margin-bottom: 30px; }
.features-grid { display: flex; flex-wrap: wrap; gap: 20px; }
.feature-card { flex: 1; min-width: 250px; background: #fff; padding: 25px; text-align: center; border-radius: 10px; box-shadow: 0 2px 8px rgba(0,0,0,0.05); }
.feature-card .icon { font-size: 2.5rem; margin-bottom: 15px; }

/* ========================================================
   4. 手机端响应式 (去掉导航栏隐藏逻辑，只保留正文排版变化)
======================================================== */
@media (max-width: 768px) {
  /* 当屏幕特别小的时候，适当缩小文字和间距，确保能放得下全部菜单 */
  .logo { font-size: 1.1rem; }
  .nav-links { gap: 0.8rem; }
  .nav-links a { font-size: 0.85rem; }
  
  .images-row { flex-direction: column; }
  .hero-buttons .btn { flex: 1; min-width: 100%; }
}
/* ========================================================
   5. 页脚样式
======================================================== */
.site-footer {
    text-align: center;
    padding: 25px 15px;
    margin-top: 20px;
    color: #6b7280; /* 灰颜色，显得高级且不抢眼 */
    font-size: 0.9rem;
    border-top: 1px solid #e5e7eb; /* 顶部加一条浅色分割线 */
    width: 100%;
}