/* ==========================================
   全局重置 + 腾讯官网设计规范
   ========================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #0052cc;
    --primary-hover: #0047b3;
    --primary-light: #eaf1ff;
    --text-title: #1a1a1a;
    --text-body: #333333;
    --text-secondary: #666666;
    --text-placeholder: #999999;
    --bg-white: #ffffff;
    --bg-light: #f5f7fa;
    --bg-gray: #f0f2f5;
    --border-light: #e5e6eb;
    --border-gray: #dcdfe6;
    --shadow-card: 0 2px 12px 0 rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 4px 16px 0 rgba(0, 0, 0, 0.12);
    --shadow-button: 0 2px 6px 0 rgba(0, 82, 204, 0.3);
    --header-height: 64px;
}

body {
    font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-body);
    background: var(--bg-white);
    padding-top: var(--header-height);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================
   前台头部样式（固定定位，不遮挡内容）
   ========================================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    z-index: 999;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.header-inner {
    max-width: 1200px;
    height: 100%;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.menu-btn {
    font-size: 20px;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-title);
    display: block;
}

.site-logo {
    height: 32px;
    width: auto;
}

.logo {
    font-size: 18px;
    font-weight: 600;
    color: var(--primary);
    text-decoration: none;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 32px;
}

.main-nav a {
    color: var(--text-body);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.main-nav a.active,
.main-nav a:hover {
    color: var(--primary);
}

/* ==========================================
   侧滑菜单样式
   ========================================== */
.sidebar {
    position: fixed;
    top: 0;
    left: -300px;
    width: 300px;
    height: 100vh;
    background: var(--bg-white);
    z-index: 1000;
    transition: left 0.3s ease;
    box-shadow: 2px 0 12px rgba(0,0,0,0.1);
}

.sidebar.open {
    left: 0;
}

.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.close-btn {
    font-size: 24px;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-secondary);
}

.sidebar-menu {
    list-style: none;
    padding: 20px;
}

.sidebar-menu li {
    margin-bottom: 16px;
}

.sidebar-menu a {
    color: var(--text-body);
    text-decoration: none;
    font-size: 16px;
}

.sidebar-menu a:hover {
    color: var(--primary);
}

.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(0,0,0,0.3);
    z-index: 998;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.overlay.show {
    opacity: 1;
    visibility: visible;
}

/* ==========================================
   首页专属样式（Hero、卡片等）
   ========================================== */
.hero {
    width: 100%;
    min-height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.4)), var(--hero-bg, url('uploads/company.jpg')) center/cover;
    color: #fff;
    margin-top: 0;
}
.hero-content {
    max-width: 800px;
    padding: 0 20px;
}
.hero h1 {
    font-size: clamp(2rem, 6vw, 3rem);
    margin-bottom: 16px;
}
.hero p {
    font-size: clamp(1rem, 4vw, 1.2rem);
    margin-bottom: 32px;
}
.btn {
    padding: 12px 32px;
    border-radius: 999px;
    text-decoration: none;
    font-weight: 600;
    display: inline-block;
    margin: 0 8px;
    transition: all 0.3s;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
}
.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,82,204,0.3);
}
.btn-outline {
    border: 1px solid #fff;
    color: #fff;
}
.btn-outline:hover {
    background: #fff;
    color: var(--primary);
}
.section {
    padding: 64px 0;
}
.section-header {
    text-align: center;
    margin-bottom: 48px;
}
.section-header h2 {
    font-size: clamp(1.8rem, 5vw, 2rem);
    margin-bottom: 8px;
}
.section-header p {
    color: var(--text-secondary);
}
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}
.card {
    background: #fff;
    border-radius: 12px;
    box-shadow: var(--shadow-card);
    overflow: hidden;
    transition: transform 0.2s, box-shadow 0.2s;
}
.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}
.card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform 0.3s;
}
.card:hover img {
    transform: scale(1.02);
}
.card-info {
    padding: 20px;
}
.card-info h3 {
    margin-bottom: 8px;
    font-size: 1.2rem;
}
.card-info p {
    color: var(--text-secondary);
    margin-bottom: 12px;
}
.card-price {
    font-weight: 700;
    color: var(--primary);
    font-size: 1.2rem;
}
.bg-light {
    background: var(--bg-light);
}
.host-card .card-info {
    text-align: center;
}
.feedback-card {
    background: #fff;
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow-card);
    transition: all 0.2s;
}
.feedback-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}
.feedback-icon {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 16px;
}
.feedback-card h4 {
    margin-bottom: 12px;
    font-size: 1.1rem;
}
.feedback-card p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 16px;
}
.feedback-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}
.feedback-link:hover {
    gap: 8px;
}
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}
.about-text h2 {
    font-size: 2rem;
    margin-bottom: 16px;
}
.about-text p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
}
.about-image img {
    width: 100%;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.btn-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}
.btn-link:hover {
    gap: 8px;
}
.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}
.scroll-reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* ==========================================
   后台样式（保留原有所有样式，确保UI不丢失）
   ========================================== */
.admin-container {
    max-width: 1400px;
    margin: 2rem auto;
    padding: 0 2rem;
}
.admin-content {
    background: white;
    border-radius: 1.5rem;
    padding: 2rem;
    box-shadow: 0 10px 25px -5px rgba(0,0,0,0.05);
    border: 1px solid #e2e8f0;
}
.admin-content h1 {
    margin-top: 0;
    margin-bottom: 1.5rem;
    font-size: 2rem;
}
.admin-content table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1.5rem;
    border: none;
}
.admin-content th {
    background: #f8fafc;
    font-weight: 600;
    color: #1e293b;
    padding: 1rem;
    text-align: left;
    border-bottom: 2px solid #e2e8f0;
}
.admin-content td {
    padding: 1rem;
    border-bottom: 1px solid #f1f5f9;
    color: #334155;
}
.admin-content tr:last-child td {
    border-bottom: none;
}
.admin-content .btn,
.admin-content button {
    background: #3b82f6;
    color: #ffffff;
    border-radius: 2rem;
    padding: 0.5rem 1.5rem;
    font-size: 0.9rem;
    border: none;
    cursor: pointer;
}
.admin-content .btn-sm {
    padding: 0.3rem 1rem;
    font-size: 0.85rem;
}
.admin-content a {
    color: #3b82f6;
    text-decoration: none;
    margin: 0 0.3rem;
}
.admin-content .btn-secondary {
    background: #e2e8f0;
    color: #1e293b;
    margin-left: 0.5rem;
    padding: 0.5rem 1.5rem;
    border-radius: 2rem;
    font-size: 0.9rem;
    transition: background 0.15s;
    display: inline-block;
    border: none;
    cursor: pointer;
    text-decoration: none;
}
.admin-content .btn-secondary:hover {
    background: #cbd5e1;
    color: #1e293b;
}
.admin-content form {
    background: transparent;
    padding: 0;
    box-shadow: none;
    border: none;
    max-width: 100%;
}
.admin-content form div {
    margin-bottom: 1.5rem;
}
.admin-content label {
    font-weight: 500;
    margin-bottom: 0.3rem;
    color: #1e293b;
    display: block;
}
.admin-content input[type="text"],
.admin-content input[type="password"],
.admin-content textarea,
.admin-content select {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    width: 100%;
    transition: all 0.2s;
    font-family: inherit;
}
.admin-content input:focus,
.admin-content textarea:focus {
    border-color: #3b82f6;
    box-shadow: 0 0 0 3px rgba(59,130,246,0.1);
    background: white;
    outline: none;
}
.admin-card-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}
.admin-card {
    background: white;
    border-radius: 1.5rem;
    padding: 2rem 1.5rem;
    box-shadow: 0 10px 20px -5px rgba(0,0,0,0.05);
    border: 1px solid #e2e8f0;
    transition: transform 0.2s, box-shadow 0.2s;
    text-align: center;
}
.admin-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 25px -5px rgba(0,0,0,0.1);
    border-color: #cbd5e1;
}
.admin-card a {
    text-decoration: none;
    color: inherit;
}
.admin-card .card-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #3b82f6;
}
.admin-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #0f172a;
}
.admin-card p {
    color: #64748b;
    font-size: 0.9rem;
    margin: 0;
}
.login-page {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0;
    padding: 0;
}
.login-container {
    background: white;
    border-radius: 1.5rem;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    padding: 2.5rem;
    width: 100%;
    max-width: 400px;
    text-align: center;
}
.login-container h2 {
    margin-bottom: 2rem;
    color: #0f172a;
    font-weight: 600;
}
.login-container input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #e2e8f0;
    border-radius: 0.75rem;
    margin-bottom: 1rem;
    font-size: 1rem;
}
.login-container button {
    width: 100%;
    padding: 0.75rem;
    background: #3b82f6;
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s;
}
.login-container button:hover {
    background: #2563eb;
}

/* ==========================================
   响应式适配
   ========================================== */
@media (max-width: 1024px) {
    .grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .feedback-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .about-grid {
        gap: 32px;
    }
}
@media (max-width: 768px) {
    .menu-btn {
        display: block;
    }
    .main-nav {
        display: none;
    }
    .grid,
    .feedback-grid {
        grid-template-columns: 1fr;
    }
    .about-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    .section {
        padding: 48px 0;
    }
    .section-header {
        margin-bottom: 32px;
    }
    .hero {
        min-height: 400px;
    }
    /* 后台移动端适配 */
    .admin-container {
        padding: 0 1rem;
    }
    .admin-card-container {
        grid-template-columns: 1fr;
    }
}
@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.75rem;
    }
    .hero p {
        font-size: 0.9rem;
    }
    .btn {
        padding: 8px 20px;
        font-size: 0.9rem;
    }
    .container {
        padding: 0 16px;
    }
}
/* 页脚样式 */
footer {
    text-align: center;
    padding: 1.5rem 0;
    color: #666;
    border-top: 1px solid #eef2f6;
    margin-top: 2rem;
}