/* ========================================
   晋中星际科技 - 官网公共样式 common.css
   适用：所有官网页面（index/about/services/cases/contact）
   说明：设计系统变量、基础重置、导航栏、页脚、工具类、动画、响应式
   ======================================== */

/* ------- 基础重置与字体 ------- */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: 'Inter', 'Microsoft YaHei', 'PingFang SC', sans-serif;
    line-height: 1.6;
    color: #000;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a { text-decoration: none; color: inherit; }
button { cursor: pointer; border: none; font-family: inherit; }
ul, ol { list-style: none; }
img { max-width: 100%; height: auto; }

/* ------- 设计系统变量 ------- */
:root {
    /* 品牌色 */
    --brand-deep: #003B73;
    --brand-bright: #00A5FF;
    --brand-orange: #FF6B35;
    --success-green: #10B981;
    --warning-yellow: #F59E0B;
    --error-red: #EF4444;
    --info-blue: #3B82F6;

    /* 中性色 */
    --text-black: #000000;
    --text-dark: #333333;
    --text-medium: #666666;
    --text-light: #999999;
    --border-gray: #E5E7EB;
    --bg-gray: #F5F5F5;
    --bg-white: #FFFFFF;

    /* 阴影 */
    --shadow-card: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-hover: 0 20px 40px rgba(0,0,0,0.08);
    --shadow-nav: 0 1px 10px rgba(0,0,0,0.08);

    /* 圆角 */
    --radius-card: 16px;
    --radius-button: 12px;
    --radius-input: 8px;

    /* 间距 */
    --space-section-pc: 120px;
    --space-section-tablet: 100px;
    --space-section-mobile: 80px;
    --pad-card: 32px;
    --pad-button: 16px 40px;
    --gap-card-pc: 32px;
    --gap-card-mobile: 24px;
}

/* ------- 工具类 ------- */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 40px;
}

.section {
    padding: var(--space-section-pc) 0;
}

.section__header {
    text-align: center;
    margin-bottom: 60px;
}

.section__title {
    font-size: 48px;
    font-weight: 700;
    color: var(--text-black);
    line-height: 1.2;
    margin-bottom: 16px;
}

.section__subtitle {
    font-size: 18px;
    color: var(--text-medium);
    max-width: 600px;
    margin: 0 auto;
}

/* ------- 按钮样式 ------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--pad-button);
    border-radius: var(--radius-button);
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    text-decoration: none;
}

.btn--primary {
    background: var(--brand-orange);
    color: #fff;
}
.btn--primary:hover {
    background: #E55A24;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255,107,53,0.3);
}

.btn--secondary {
    background: var(--brand-bright);
    color: #fff;
}
.btn--secondary:hover {
    background: #0094E6;
    transform: translateY(-2px);
}

.btn--outline {
    background: transparent;
    color: var(--brand-bright);
    border: 2px solid var(--brand-bright);
}
.btn--outline:hover {
    background: var(--brand-bright);
    color: #fff;
}

.btn--white {
    background: #fff;
    color: var(--brand-deep);
    font-weight: 700;
}
.btn--white:hover {
    background: #f0f0f0;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.15);
}

/* ------- 滚动渐入动画 ------- */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   导航栏 Navbar
   透明背景，滚动后变为实心白色
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: transparent;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

/* 内页导航栏默认为实心（非透明），首页 hero 区为透明 */
.navbar.navbar--solid,
.navbar.scrolled {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-nav);
}

.navbar__inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 16px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar__logo {
    font-size: 24px;
    font-weight: 700;
    color: #fff;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: color 0.3s ease;
    text-decoration: none;
}

.navbar.scrolled .navbar__logo,
.navbar.navbar--solid .navbar__logo {
    color: var(--brand-deep);
}

.navbar__logo-icon {
    width: 42px;
    height: 42px;
    background: linear-gradient(135deg, var(--brand-deep), var(--brand-bright));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 800;
    font-size: 20px;
    flex-shrink: 0;
}

.navbar__links {
    display: flex;
    align-items: center;
    gap: 36px;
    list-style: none;
}

.navbar__link {
    font-size: 15px;
    font-weight: 500;
    color: rgba(255,255,255,0.9);
    transition: color 0.2s ease;
    text-decoration: none;
    position: relative;
}

.navbar.scrolled .navbar__link,
.navbar.navbar--solid .navbar__link {
    color: var(--text-dark);
}

.navbar__link:hover,
.navbar__link.active {
    color: var(--brand-bright);
}

.navbar__cta {
    background: var(--brand-orange);
    color: #fff !important;
    padding: 10px 24px;
    border-radius: var(--radius-button);
    font-size: 14px;
    font-weight: 600;
    transition: background 0.2s ease;
    text-decoration: none;
}
.navbar__cta:hover {
    background: #E55A24;
}

.navbar__lang-toggle {
    background: transparent;
    color: rgba(255,255,255,0.95);
    font-size: 14px;
    font-weight: 600;
    padding: 6px 12px;
    border-radius: var(--radius-input);
    transition: all 0.2s ease;
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
    border: none;
}
.navbar.scrolled .navbar__lang-toggle,
.navbar.navbar--solid .navbar__lang-toggle {
    color: var(--text-dark);
    text-shadow: none;
    border: none;
}
.navbar__lang-toggle:hover {
    color: var(--brand-bright);
}

/* 移动端菜单按钮 */
.navbar__toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    padding: 5px;
    border: none;
    cursor: pointer;
}
.navbar__toggle span {
    width: 24px;
    height: 2px;
    background: #fff;
    border-radius: 2px;
    transition: all 0.3s ease;
}
.navbar.scrolled .navbar__toggle span,
.navbar.navbar--solid .navbar__toggle span {
    background: var(--text-dark);
}
.navbar__toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}
.navbar__toggle.active span:nth-child(2) {
    opacity: 0;
}
.navbar__toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* ========================================
   页脚 Footer
   ======================================== */
.footer {
    background: linear-gradient(135deg, #000000 0%, var(--brand-deep) 100%);
    color: rgba(255,255,255,0.8);
    padding: 80px 40px 40px;
}

.footer__grid {
    max-width: 1280px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 60px;
    padding-bottom: 60px;
    border-bottom: 1px solid rgba(255,255,255,0.15);
}

.footer__col-title {
    color: #fff;
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer__col-text {
    font-size: 14px;
    line-height: 1.8;
    color: rgba(255,255,255,0.6);
    margin-bottom: 20px;
}

.footer__logo {
    font-size: 22px;
    font-weight: 700;
    color: #fff;
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
    text-decoration: none;
}

.footer__logo-icon {
    width: 38px;
    height: 38px;
    background: linear-gradient(135deg, var(--brand-deep), var(--brand-bright));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 800;
    font-size: 18px;
}

.footer__links { list-style: none; }
.footer__links li { margin-bottom: 12px; }
.footer__links a {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    transition: color 0.2s ease;
    text-decoration: none;
}
.footer__links a:hover { color: var(--brand-bright); }

.footer__contact-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 14px;
    font-size: 14px;
    color: rgba(255,255,255,0.7);
}
.footer__contact-icon { flex-shrink: 0; margin-top: 2px; }

.footer__bottom {
    max-width: 1280px;
    margin: 30px auto 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: rgba(255,255,255,0.5);
    flex-wrap: wrap;
    gap: 10px;
}
.footer__bottom-links { display: flex; gap: 20px; }
.footer__bottom-links a {
    color: rgba(255,255,255,0.5);
    text-decoration: none;
    transition: color 0.2s ease;
}
.footer__bottom-links a:hover { color: var(--brand-bright); }
.footer__bottom-right { display: flex; align-items: center; flex-wrap: wrap; gap: 18px; }
/* 页脚访客计数器：与 ICP 备案号水平平齐，同色低对比 */
.site-counter {
    display: inline-flex; align-items: center; gap: 6px;
    color: rgba(255,255,255,0.5); font-size: 13px;
    letter-spacing: .02em; background: transparent; white-space: nowrap;
}

/* ========================================
   通用页面 Hero（内页顶部横幅）
   ======================================== */
.page-hero {
    background: linear-gradient(135deg, var(--brand-deep) 0%, var(--brand-bright) 100%);
    color: #fff;
    padding: 160px 40px 80px;
    text-align: center;
}
.page-hero__title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 16px;
    line-height: 1.2;
}
.page-hero__subtitle {
    font-size: 18px;
    color: rgba(255,255,255,0.85);
    max-width: 600px;
    margin: 0 auto;
}

/* ========================================
   响应式 - 768px (平板竖屏 / 移动端)
   ======================================== */
@media (max-width: 768px) {
    .container { padding: 0 20px; }

    /* 导航栏移动端 */
    .navbar__inner { padding: 14px 20px; }
    .navbar__links {
        display: none;
        position: fixed;
        top: 73px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 24px 20px;
        box-shadow: 0 10px 30px rgba(0,0,0,0.1);
        gap: 0;
    }
    .navbar__links.open { display: flex; }
    .navbar__links li { width: 100%; }
    .navbar__link {
        display: block;
        padding: 12px 0;
        color: var(--text-dark) !important;
        border-bottom: 1px solid var(--border-gray);
    }
    .navbar__cta {
        display: block;
        text-align: center;
        margin-top: 12px;
        border-radius: var(--radius-button);
    }
    .navbar__toggle { display: flex; }

    .section { padding: var(--space-section-mobile) 0; }
    .section__title { font-size: 32px; }

    .page-hero { padding: 120px 20px 60px; }
    .page-hero__title { font-size: 32px; }

    .footer { padding: 60px 20px 30px; }
    .footer__grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .footer__bottom {
        flex-direction: column;
        text-align: center;
    }
}