/* ========================================
   ConnectBook - 全局样式
   设计：深浅搭配，层次分明
   ======================================== */

/* 重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 基础 */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: #1f2937;
    background-color: #f9fafb;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: #4f46e5;
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: #4338ca;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ========================================
   导航栏 - 深色背景
   ======================================== */
.navbar {
    background-color: #0f172a;
    height: 64px;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

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

.logo {
    font-size: 22px;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: -0.3px;
}

.logo:hover {
    color: #e2e8f0;
}

/* 图片 LOGO（后台"基本设置"上传后启用） */
.logo .logo-image {
    display: block;
    height: 36px;
    width: auto;
    max-width: 200px;
    object-fit: contain;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
    align-items: center;
}

.nav-menu a {
    color: #cbd5e1;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    font-size: 15px;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #ffffff;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #4f46e5;
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: #ffffff;
    transition: 0.3s;
}

/* ========================================
   按钮
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    border: none;
    transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
    text-decoration: none;
    line-height: 1.4;
}

.btn-primary {
    background-color: #0f172a;
    color: #ffffff;
}

.btn-primary:hover {
    background-color: #1e293b;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-secondary {
    background-color: #ffffff;
    color: #0f172a;
    border: 1px solid #e2e8f0;
}

.btn-secondary:hover {
    background-color: #f8fafc;
}

.btn-sm {
    padding: 6px 14px;
    font-size: 14px;
}

.btn-danger {
    background-color: #ef4444;
    color: white;
}

.btn-danger:hover {
    background-color: #dc2626;
    color: white;
}

/* 导航栏认证按钮 */
.nav-menu .nav-auth-btn {
    padding: 6px 16px;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s ease;
}

.nav-menu .nav-auth-btn.login {
    background-color: transparent;
    color: #cbd5e1;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-menu .nav-auth-btn.login:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: #ffffff;
    border-color: rgba(255, 255, 255, 0.4);
}

.nav-menu .nav-auth-btn.register {
    background-color: #3b82f6;
    color: #ffffff;
    border: 1px solid #3b82f6;
}

.nav-menu .nav-auth-btn.register:hover {
    background-color: #2563eb;
    border-color: #2563eb;
}

/* ========================================
   卡片
   ======================================== */
.card {
    background: #ffffff;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
    overflow: hidden;
}

/* ========================================
   表单
   ======================================== */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    color: #374151;
    font-size: 14px;
}

.form-control {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 15px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    background-color: #ffffff;
}

.form-control:focus {
    outline: none;
    border-color: #4f46e5;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* ========================================
   警告框
   ======================================== */
.alert {
    padding: 14px 18px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-size: 14px;
}

.alert-error {
    background-color: #fef2f2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

.alert-success {
    background-color: #ecfdf5;
    color: #155724;
    border: 1px solid #a7f3d0;
}

/* ========================================
   分页
   ======================================== */
.pagination {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 24px;
}

.pagination a {
    padding: 8px 14px;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    color: #374151;
    font-size: 14px;
}

.pagination a.active,
.pagination a:hover {
    background-color: #0f172a;
    color: #ffffff;
    border-color: #0f172a;
}

/* ========================================
   页脚 - 深色
   ======================================== */
.footer {
    background-color: #0f172a;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    padding: 32px 0;
    text-align: center;
    color: #94a3b8;
    margin-top: 60px;
}

.footer p {
    font-size: 14px;
}

/* ========================================
   工具类
   ======================================== */
.text-center {
    text-align: center;
}

.mb-0 {
    margin-bottom: 0;
}

.mt-1 {
    margin-top: 8px;
}

.mt-2 {
    margin-top: 16px;
}

.mb-1 {
    margin-bottom: 8px;
}

.mb-2 {
    margin-bottom: 16px;
}

/* ========================================
   响应式
   ======================================== */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: #0f172a;
        flex-direction: column;
        padding: 16px;
        gap: 8px;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-menu a {
        padding: 12px 16px;
        width: 100%;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .container {
        padding: 0 16px;
    }
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background-color: #f9fafb;
    border-top: 1px solid #e5e7eb;
    padding: 32px 0;
    margin-top: 64px;
    text-align: center;
    color: #6b7280;
    font-size: 14px;
}

.footer .container p {
    margin: 0;
    line-height: 1.8;
}

.footer .beian-info {
    margin-top: 8px;
    color: #9ca3af;
}

.footer .beian-info a {
    color: #9ca3af;
    text-decoration: underline;
}

.footer .beian-info a:hover {
    color: #6b7280;
}