/* ===== CSS 变量（舒适用色与间距） ===== */
:root {
    --color-bg-base: #F5F7FA;
    --color-bg-surface: #FFFFFF;
    --color-bg-elevated: #FFFFFF;
    --color-bg-overlay: rgba(0, 0, 0, 0.45);

    --color-text-primary: #1F2A3A;
    --color-text-secondary: #6B7A8E;
    --color-text-muted: #9AABBC;
    --color-text-inverse: #FFFFFF;

    --color-accent: #2B6C9E;
    --color-accent-hover: #1E527A;
    --color-accent-dim: rgba(43, 108, 158, 0.06);

    --color-border: #E2E8F0;
    --color-border-dark: #CBD0D8;

    --color-shadow-sm: 0 8px 24px rgba(0, 0, 0, 0.04);
    --color-shadow-md: 0 16px 40px rgba(0, 0, 0, 0.06);
    --color-shadow-lg: 0 24px 56px rgba(0, 0, 0, 0.08);

    --color-gradient-main: linear-gradient(135deg, #2B6C9E 0%, #5D8AB0 100%);
    --color-gradient-subtle: linear-gradient(135deg, rgba(43, 108, 158, 0.03) 0%, rgba(93, 138, 176, 0.03) 100%);

    /* ----- LOGO 配色（白天） ----- */
    --logo-primary: #1F2A3A;
    --logo-secondary: #4A5A6E;

    /* ----- Hero 背景（白天）更深更明显 ----- */
    --color-hero-bg: #DCE4F0;

    /* ----- 间距 ----- */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 2rem;
    --space-xl: 2.5rem;
    --space-2xl: 3.5rem;
    --space-3xl: 5rem;
    --space-4xl: 7rem;

    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 9999px;

    --transition-duration: 0.3s;
    --transition-timing: ease;
}

[data-theme="dark"] {
    --color-bg-base: #1A222C;
    --color-bg-surface: #222E3A;
    --color-bg-elevated: #2A3A48;
    --color-bg-overlay: rgba(0, 0, 0, 0.6);

    --color-text-primary: #E8ECF0;
    --color-text-secondary: #9AABBC;
    --color-text-muted: #5E6F82;
    --color-text-inverse: #FFFFFF;

    --color-accent: #5D8AB0;
    --color-accent-hover: #7A9EBF;
    --color-accent-dim: rgba(93, 138, 176, 0.10);

    --color-border: #2C3540;
    --color-border-dark: #3A4552;

    --color-shadow-sm: 0 8px 24px rgba(0, 0, 0, 0.3);
    --color-shadow-md: 0 16px 40px rgba(0, 0, 0, 0.4);
    --color-shadow-lg: 0 24px 56px rgba(0, 0, 0, 0.5);

    --color-gradient-main: linear-gradient(135deg, #2B6C9E 0%, #5D8AB0 100%);
    --color-gradient-subtle: linear-gradient(135deg, rgba(93, 138, 176, 0.08) 0%, rgba(43, 108, 158, 0.08) 100%);

    /* ----- LOGO 配色（夜间） ----- */
    --logo-primary: #FFFFFF;
    --logo-secondary: #9AABBC;

    /* ----- Hero 背景（夜间）更深沉 ----- */
    --color-hero-bg: #121A24;
}

/* ===== 全局重置 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    scroll-behavior: smooth;
}
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
    background-color: var(--color-bg-base);
    color: var(--color-text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-duration) var(--transition-timing),
                color var(--transition-duration) var(--transition-timing);
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}
.section {
    padding: var(--space-4xl) 0;
}

/* ===== 排版 ===== */
.section-title {
    font-size: clamp(1.5rem, 2.6vw, 2rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.3;
    margin-bottom: var(--space-sm);
    color: var(--color-text-primary);
}
.section-sub {
    color: var(--color-text-secondary);
    font-size: 1rem;
    max-width: 640px;
    margin: 0 auto var(--space-xl);
    line-height: 1.7;
}
.text-center { text-align: center; }

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1.25rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all var(--transition-duration) var(--transition-timing);
    text-decoration: none;
    font-family: inherit;
    white-space: nowrap;
}
.btn:active { transform: scale(0.96); }
.btn-primary {
    background: var(--color-gradient-main);
    color: var(--color-text-inverse);
    box-shadow: var(--color-shadow-sm);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--color-shadow-md);
}
.btn-outline {
    background: transparent;
    color: var(--color-text-secondary);
    border: 1.5px solid var(--color-border);
}
.btn-outline:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
    background: var(--color-accent-dim);
}
.btn-sm {
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
}

/* ===== 卡片 ===== */
.card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-xl) var(--space-2xl);
    transition: all var(--transition-duration) var(--transition-timing);
    box-shadow: var(--color-shadow-sm);
}
.card:hover {
    border-color: var(--color-accent);
    transform: translateY(-4px);
    box-shadow: var(--color-shadow-md);
}

/* ===== 导航（修复手机按钮挤压） ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--color-bg-surface);
    backdrop-filter: blur(12px) saturate(1.2);
    border-bottom: 1px solid var(--color-border);
    height: 64px;
    display: flex;
    align-items: center;
}
.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    height: 100%;
}
.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    flex-shrink: 0;
    height: 28px;
    margin-right: 4px;
}
.logo object {
    display: block;
    height: 28px;
    width: auto;
}
.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    flex: 1;
    justify-content: center;
}
.nav-menu a {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    padding: 0.375rem 0.875rem;
    border-radius: var(--radius-full);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
}
.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 60%;
    height: 2px;
    background: var(--color-accent);
    border-radius: 2px;
    transition: transform var(--transition-duration) var(--transition-timing);
}
.nav-menu a:hover::after { transform: translateX(-50%) scaleX(1); }
.nav-menu a:hover { color: var(--color-text-primary); }

.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-shrink: 0;
}
.nav-actions .phone {
    color: var(--color-text-secondary);
    font-size: 0.813rem;
    display: flex;
    align-items: center;
    gap: 4px;
    text-decoration: none;
    font-weight: 500;
}
.nav-actions .phone svg {
    width: 16px;
    height: 16px;
    fill: var(--color-accent);
}
.nav-actions .btn {
    padding: 0.35rem 0.9rem;
    font-size: 0.8rem;
}
.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--color-text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    padding: var(--space-xs);
    flex-shrink: 0;
    margin-right: 2px;
}

/* ===== Hero（背景加深） ===== */
.hero {
    padding: calc(64px + var(--space-4xl)) 0 calc(var(--space-4xl) * 0.7);
    background: var(--color-hero-bg);
    text-align: center;
    position: relative;
    overflow: hidden;
    transition: background var(--transition-duration) var(--transition-timing);
}
.hero::before {
    content: '';
    position: absolute;
    top: -40%;
    right: -20%;
    width: 60%;
    height: 80%;
    background: radial-gradient(ellipse, rgba(43, 108, 158, 0.08) 0%, transparent 70%);
    pointer-events: none;
}
.hero h1 {
    font-size: clamp(2.6rem, 6vw, 4.2rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    margin-bottom: var(--space-md);
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: baseline;
    gap: 0 12px;
}
.hero h1 .highlight {
    background: var(--color-gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-features {
    list-style: none;
    margin-bottom: var(--space-xl);
}
.hero-features li {
    color: var(--color-text-secondary);
    font-size: 0.938rem;
    line-height: 1.8;
    padding: 2px 0;
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 8px;
}
.hero-features li::before {
    content: '◆';
    color: var(--color-accent);
    font-size: 10px;
    opacity: 0.5;
}
.hero-btns {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-md);
}
.hero-btns .btn {
    padding: 0.625rem 1.75rem;
    font-size: 0.875rem;
    min-width: 140px;
}

/* ===== 关于（无特殊背景，与其他区域一致） ===== */
#about {
    /* 不再设置背景色，保持默认透明 */
    transition: background var(--transition-duration) var(--transition-timing);
}

.about-title-wrap {
    text-align: center;
    margin-bottom: var(--space-2xl);
}
.about-title-wrap .section-title {
    margin-bottom: var(--space-sm);
}
.about-title-wrap .section-sub {
    margin: 0 auto var(--space-xl);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-4xl);
    align-items: center;
}
.about-content .desc-text {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-md);
    font-size: 0.95rem;
}
.about-stats {
    display: flex;
    gap: var(--space-xl);
    margin-bottom: var(--space-md);
    flex-wrap: wrap;
}
.about-stats .stat .num {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-accent);
    line-height: 1;
}
.about-stats .stat .label {
    color: var(--color-text-muted);
    font-size: 0.813rem;
}
.about-global {
    font-size: 0.938rem;
    color: var(--color-text-secondary);
}
.about-global span {
    color: var(--color-accent);
    font-weight: 600;
}
.visual-placeholder {
    background: var(--color-bg-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-lg) var(--space-md) var(--space-md);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xs);
    min-height: 200px;
    justify-content: center;
    position: relative;
    overflow: hidden;
}
.visual-placeholder::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--color-gradient-subtle);
    pointer-events: none;
}
.visual-placeholder canvas {
    display: block;
    width: 100%;
    max-width: 200px;
    aspect-ratio: 1/1;
    border-radius: 50%;
    background: transparent;
    position: relative;
    z-index: 1;
}
.visual-placeholder .label {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    letter-spacing: 0.5px;
    position: relative;
    z-index: 1;
}

/* ===== 产品 ===== */
.product-header {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--color-border);
}
.product-header svg {
    width: 26px;
    height: 26px;
    stroke: var(--color-accent);
    fill: none;
    stroke-width: 1.8;
}
.product-header h2 {
    font-size: 1.4rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-text-primary);
}
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-2xl);
}
.product-card .icon-wrap {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-sm);
    background: var(--color-accent-dim);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-md);
}
.product-card .icon-wrap svg {
    width: 24px;
    height: 24px;
    stroke: var(--color-accent);
    fill: none;
}
.product-card .name {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 4px;
    color: var(--color-text-primary);
}
.product-card .name .highlight { color: var(--color-accent); }
.product-card .desc {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    line-height: 1.7;
    margin-bottom: 4px;
}
.product-card .spec-list {
    list-style: none;
    margin: var(--space-sm) 0 var(--space-md);
    padding: 0;
    font-size: 0.813rem;
    color: var(--color-text-secondary);
    display: flex;
    flex-direction: column;
    gap: 2px;
}
.product-card .spec-list li {
    padding: 2px 0;
    display: flex;
    align-items: baseline;
    gap: 6px;
    line-height: 1.5;
}
.product-card .spec-list li strong {
    color: var(--color-text-primary);
    font-weight: 600;
    min-width: 48px;
    flex-shrink: 0;
}
.product-card .btn-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-top: var(--space-md);
}
.product-card .btn-group .btn {
    flex: 1 1 auto;
    min-width: 80px;
    justify-content: center;
}
.product-card .btn-group-server {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-top: var(--space-md);
    align-items: center;
}
.product-card .btn-group-server .prefix {
    font-size: 0.813rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    margin-right: 2px;
    white-space: nowrap;
    flex: 0 0 auto;
}
.product-card .btn-group-server .btn {
    flex: 1 1 0;
    min-width: 0;
    justify-content: center;
    text-align: center;
    padding: 0.25rem 0.625rem;
    font-size: 0.75rem;
}

/* ===== 联系 ===== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
}
#contact {
    scroll-margin-top: 70px;
    padding-top: 2rem;
    padding-bottom: 10rem;
}

.contact-card h5 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
    color: var(--color-text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}
.contact-card h5::before {
    content: '';
    width: 4px;
    height: 18px;
    background: var(--color-accent);
    border-radius: 4px;
}
.contact-item {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 4px 10px;
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--color-border);
}
.contact-item:last-child { border-bottom: none; }
.contact-item a {
    color: var(--color-text-secondary);
    font-size: 0.813rem;
    text-decoration: none;
}
.contact-item a:hover { color: var(--color-accent); }
.contact-item svg {
    width: 16px;
    height: 16px;
    stroke: var(--color-text-muted);
    fill: none;
    flex-shrink: 0;
}
.contact-item .label {
    color: var(--color-text-muted);
    font-size: 0.75rem;
}

/* ===== 合作伙伴 ===== */
.partner-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-md) var(--space-lg);
    padding: var(--space-md) 0;
}
.partner-tag {
    color: var(--color-text-muted);
    font-size: 0.813rem;
    font-weight: 500;
    padding: 0.375rem 1.25rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    background: var(--color-bg-surface);
    transition: all var(--transition-duration) var(--transition-timing);
    letter-spacing: 0.3px;
}
.partner-tag:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
    transform: translateY(-2px);
    box-shadow: var(--color-shadow-sm);
}

/* ===== Footer ===== */
.footer {
    background: var(--color-bg-surface);
    border-top: 1px solid var(--color-border);
    color: var(--color-text-secondary);
    padding: var(--space-2xl) 0 var(--space-lg);
    margin-top: 0;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: var(--space-2xl);
}
.footer-brand .logo { display: inline-flex; }
.footer-brand p {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    max-width: 320px;
    line-height: 1.7;
    margin-top: var(--space-sm);
}
.footer-widget h4 {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-sm);
    letter-spacing: 0.5px;
}
.footer-widget .qr-img {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    background: var(--color-bg-base);
    padding: 4px;
}
.footer-bottom {
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-xl);
    padding-top: var(--space-md);
    text-align: center;
    font-size: 0.813rem;
    color: var(--color-text-muted);
}
.footer-bottom a {
    color: var(--color-text-muted);
    text-decoration: none;
}
.footer-bottom a:hover { color: var(--color-accent); }

/* ===== Modal ===== */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: var(--color-bg-overlay);
    backdrop-filter: blur(4px);
    align-items: center;
    justify-content: center;
    padding: var(--space-lg);
}
.modal-overlay.active { display: flex; }
.modal-box {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-md);
    max-width: 360px;
    width: 100%;
    padding: var(--space-xl);
    box-shadow: var(--color-shadow-lg);
    transform: scale(0.96) translateY(20px);
    opacity: 0;
    transition: all var(--transition-duration) var(--transition-timing);
    border: 1px solid var(--color-border);
}
.modal-overlay.active .modal-box {
    transform: scale(1) translateY(0);
    opacity: 1;
}
.modal-box .header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-md);
}
.modal-box .header h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-primary);
}
.modal-box .close {
    background: none;
    border: none;
    color: var(--color-text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0 4px;
}
.modal-box .close:hover { color: var(--color-text-primary); }
.modal-box .qr-img {
    width: 100%;
    max-width: 280px;
    display: block;
    margin: 0 auto;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
}

/* ===== 工具 ===== */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s var(--transition-timing), transform 0.7s var(--transition-timing);
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
    .reveal { opacity: 1; transform: none; }
    .card:hover, .btn:hover { transform: none !important; }
}

/* ===== 响应式 ===== */
@media (max-width: 992px) {
    .nav-toggle { display: block; }
    .nav-menu {
        display: none;
        flex-direction: column;
        align-items: stretch;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--color-bg-surface);
        border-bottom: 1px solid var(--color-border);
        padding: var(--space-md) var(--space-lg);
        gap: 2px;
        box-shadow: var(--color-shadow-md);
    }
    .nav-menu.open { display: flex; }
    .nav-menu a {
        padding: 0.625rem 0.75rem;
        border-radius: var(--radius-sm);
        font-size: 0.938rem;
    }
    .nav-menu a::after { display: none; }
    .about-grid {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
    .about-content .desc-text { text-align: center; }
    .about-stats { justify-content: center; }
    .about-global { text-align: center; }
    .contact-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-xl); }
    .visual-placeholder canvas { max-width: 160px; }
    #contact {
        padding-top: 1rem;
        padding-bottom: 6rem;
    }
    .nav-actions .btn {
        padding: 0.25rem 0.65rem;
        font-size: 0.7rem;
    }
    .nav-actions .phone span {
        font-size: 0;
        display: inline-block;
        width: 0;
    }
    .nav-actions .phone svg {
        width: 20px;
        height: 20px;
    }
}

@media (max-width: 640px) {
    .nav-actions .phone span { display: none; }
    .hero {
        padding: calc(64px + var(--space-2xl)) 0 var(--space-xl);
    }
    .hero h1 { font-size: 1.8rem; }
    .hero-features li { font-size: 0.875rem; }
    .hero-btns .btn {
        padding: 0.5rem 1.25rem;
        font-size: 0.813rem;
        min-width: 120px;
    }
    .about-stats { gap: var(--space-md); justify-content: center; }
    .about-stats .stat .num { font-size: 1.6rem; }
    .product-grid { grid-template-columns: 1fr; }
    .product-card .btn-group-server .btn { flex: 1 1 100%; }
    .footer-grid { grid-template-columns: 1fr; gap: var(--space-lg); }
    .section { padding: var(--space-2xl) 0; }
    .visual-placeholder canvas { max-width: 140px; }
    #contact {
        padding-top: 1rem;
        padding-bottom: 4rem;
    }
    .nav-actions .btn {
        padding: 0.2rem 0.5rem;
        font-size: 0.65rem;
    }
    .nav-actions .phone svg {
        width: 18px;
        height: 18px;
    }
}