/*  =========================================================================
**  公共样式（common.css）
**  说明：全站通用样式：CSS 变量、重置、布局、头部导航、页脚、通用组件
**  说明：移动端优先（Mobile-First），断点 768px / 1024px
**  ========================================================================= */

/*  ---------- CSS 变量（改变量即换全站主题）  ---------- */
:root {
    --color_primary: #1a6cff;
    --color_primary_dark: #1455cc;
    --color_primary_light: #e8f1ff;
    --color_bg: #ffffff;
    --color_bg_gray: #f5f7fa;
    --color_text: #1f2329;
    --color_text_secondary: #646a73;
    --color_border: #e5e8ef;
    --radius_sm: 6px;
    --radius_md: 12px;
    --radius_lg: 20px;
    --container_max: 1200px;
    --header_height: 64px;
    --font_family: -apple-system, BlinkMacSystemFont, "Segoe UI",
        "PingFang SC", "Microsoft YaHei", sans-serif;
    --transition: 0.25s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font_family);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color_text);
    background: var(--color_bg);
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--color_primary);
    text-decoration: none;
}

a:hover {
    color: var(--color_primary_dark);
}

ul,
ol {
    list-style: none;
}

h1, h2, h3, h4, h5, h6 {
    line-height: 1.3;
    font-weight: 700;
}

/*  ---------- 布局工具  ---------- */
.container {
    max-width: var(--container_max);
    margin: 0 auto;
    padding: 0 16px;
}

.section {
    padding: 48px 0;
}

.section_gray {
    background: var(--color_bg_gray);
}

.section_title {
    font-size: 26px;
    text-align: center;
    margin-bottom: 12px;
}

.section_subtitle {
    font-size: 15px;
    color: var(--color_text_secondary);
    text-align: center;
    margin-bottom: 32px;
}

/*  ---------- 通用按钮  ---------- */
.btn {
    display: inline-block;
    padding: 10px 28px;
    border-radius: var(--radius_sm);
    border: 1px solid transparent;
    font-size: 15px;
    text-align: center;
    cursor: pointer;
    transition: background var(--transition), color var(--transition);
}

.btn_primary {
    background: var(--color_primary);
    color: var(--color_bg);
}

.btn_primary:hover {
    background: var(--color_primary_dark);
    color: var(--color_bg);
}

.btn_outline {
    background: transparent;
    color: var(--color_primary);
    border-color: var(--color_primary);
}

.btn_outline:hover {
    background: var(--color_primary);
    color: var(--color_bg);
}

/*  ---------- 卡片  ---------- */
.card {
    background: var(--color_bg);
    border: 1px solid var(--color_border);
    border-radius: var(--radius_md);
    overflow: hidden;
    transition: box-shadow var(--transition), transform var(--transition);
}

.card:hover {
    box-shadow: 0 8px 24px rgba(26, 108, 255, 0.12);
    transform: translateY(-4px);
}

.card_image img {
    width: 100%;
    object-fit: cover;
}

.card_body {
    padding: 16px;
}

.card_body h3 {
    font-size: 17px;
    margin-bottom: 8px;
}

.card_body p {
    font-size: 14px;
    color: var(--color_text_secondary);
}

/*  ---------- 通用栅格  ---------- */
.grid {
    display: grid;
    gap: 16px;
    grid-template-columns: 1fr;
}

@media (min-width: 768px) {
    .grid_2 {
        grid-template-columns: repeat(2, 1fr);
    }

    .grid_3 {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1024px) {
    .grid {
        gap: 24px;
    }
}

/*  ---------- 头部导航  ---------- */
.site_header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--color_bg);
    border-bottom: 1px solid var(--color_border);
}

.header_inner {
    max-width: var(--container_max);
    margin: 0 auto;
    padding: 0 16px;
    height: var(--header_height);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand {
    display: flex;
    align-items: center;
}

.brand_img {
    height: 60px;
    width: auto;
    display: block;
}

.main_nav {
    display: none;
}

.nav_list {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav_list a {
    display: block;
    padding: 8px 14px;
    border-radius: var(--radius_sm);
    color: var(--color_text);
    font-size: 15px;
}

.nav_list a:hover,
.nav_list a.active {
    color: var(--color_primary);
    background: var(--color_primary_light);
}

/*  移动端汉堡菜单  */
.nav_toggle {
    display: inline-flex;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
    background: none;
    border: none;
    cursor: pointer;
}

.nav_toggle span {
    width: 22px;
    height: 2px;
    background: var(--color_text);
    border-radius: 2px;
    transition: transform var(--transition), opacity var(--transition);
}

.nav_toggle.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav_toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav_toggle.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

.main_nav.open {
    display: block;
    position: absolute;
    top: var(--header_height);
    left: 0;
    right: 0;
    background: var(--color_bg);
    border-bottom: 1px solid var(--color_border);
    padding: 8px 16px 16px;
}

.main_nav.open .nav_list {
    flex-direction: column;
    align-items: stretch;
}

.main_nav.open .nav_list a {
    padding: 12px 14px;
}

/*  ---------- 页脚  ---------- */
.site_footer {
    background: var(--color_text);
    color: #a9b0ba;
    padding: 40px 0 0;
}

.footer_inner {
    max-width: var(--container_max);
    margin: 0 auto;
    padding: 0 16px;
    display: grid;
    gap: 24px;
    grid-template-columns: 1fr;
}

.footer_col h3 {
    color: var(--color_bg);
    font-size: 16px;
    margin-bottom: 12px;
}

.footer_col a {
    color: #a9b0ba;
}

.footer_col a:hover {
    color: var(--color_bg);
}

.footer_col p,
.footer_col li {
    margin-bottom: 8px;
    font-size: 14px;
}

.contact_main {
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.contact_info {
    min-width: 0;
}

.contact_info p {
    margin-bottom: 8px;
    font-size: 14px;
    line-height: 1.6;
}

.contact_address {
    margin-bottom: 0;
    word-break: break-all;
}

.contact_qrcode_img {
    width: 110px;
    height: 110px;
    border-radius: var(--radius_sm);
    background: var(--color_bg);
    padding: 5px;
    flex-shrink: 0;
}

@media (min-width: 768px) {
    .contact_qrcode_img {
        width: 130px;
        height: 130px;
    }
}

.footer_bottom {
    margin-top: 32px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 16px;
    text-align: center;
    font-size: 13px;
}

.footer_bottom p {
    margin-bottom: 4px;
}

/*  ---------- 页面横幅（各内页首屏小标题区）  ---------- */
.page_hero {
    background: linear-gradient(135deg, var(--color_primary_light), var(--color_bg));
    padding: 48px 0;
    text-align: center;
}

.page_hero h1 {
    font-size: 28px;
    margin-bottom: 8px;
}

.page_hero p {
    color: var(--color_text_secondary);
    font-size: 15px;
}

/*  ---------- 内容占位提示  ---------- */
.placeholder {
    border: 1px dashed var(--color_border);
    border-radius: var(--radius_md);
    background: var(--color_bg_gray);
    color: var(--color_text_secondary);
    text-align: center;
    padding: 32px 16px;
    font-size: 14px;
}

/*  ---------- 响应式增强（平板及以上）  ---------- */
@media (min-width: 768px) {
    .section {
        padding: 64px 0;
    }

    .footer_inner {
        grid-template-columns: repeat(3, 1fr);
        gap: 32px;
    }

    .page_hero {
        padding: 64px 0;
    }
}

@media (min-width: 1024px) {
    .main_nav {
        display: block;
    }

    .nav_toggle {
        display: none;
    }
}