/* ============================================================
   氢能源展会主页 专用样式 (仅作用于 index.html)
   ============================================================ */
:root {
    --primary: #0B7A75;
    --primary-light: #12A89D;
    --primary-deep: #0E3A5C;
    --bg-light: #F5F8FA;
    --bg-white: #FFFFFF;
    --bg-dark: #0B1E2B;
    --text-main: #1A2B36;
    --text-sub: #5A6B7A;
    --accent: #E05C3A;
    --green: #2F9E44;
    --radius: 12px;
    --shadow: 0 6px 24px rgba(11, 122, 117, 0.10);
    --shadow-hover: 0 12px 32px rgba(11, 122, 117, 0.18);
    --nav-height: 64px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", "微软雅黑", sans-serif;
    color: var(--text-main);
    background-color: var(--bg-light);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
}

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

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------------- 导航栏 Navbar ---------------- */
#nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    z-index: 1000;
    display: flex;
    align-items: center;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(12px);
    box-shadow: 0 1px 10px rgba(11, 30, 43, 0.06);
    transition: background 0.3s ease;
}

.nav-inner {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 19px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 0.5px;
}

.nav-brand .brand-badge {
    width: 34px;
    height: 34px;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary-light), var(--primary-deep));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    font-weight: 800;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 6px;
    list-style: none;
}

.nav-menu a {
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-main);
    transition: color 0.2s, background 0.2s;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary);
    background: rgba(18, 168, 157, 0.10);
}

.nav-menu a.nav-cta {
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    color: #fff;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(18, 168, 157, 0.3);
}

.nav-menu a.nav-cta:hover {
    transform: translateY(-1px);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-main);
    border-radius: 2px;
    transition: all 0.3s;
}

/* ---------------- Hero 主视觉 ---------------- */
#home {
    padding-top: var(--nav-height);
    background: linear-gradient(160deg, var(--primary-deep) 0%, #0B7A75 45%, var(--primary-light) 100%);
    color: #fff;
    position: relative;
    overflow: hidden;
}

#home::before,
#home::after {
    content: "";
    position: absolute;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.12) 0%, transparent 70%);
}

#home::before {
    width: 480px;
    height: 480px;
    top: -160px;
    right: -120px;
}

#home::after {
    width: 380px;
    height: 380px;
    bottom: -140px;
    left: -100px;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 110px 24px 130px;
    max-width: 1000px;
    margin: 0 auto;
}

.hero-tag {
    display: inline-block;
    padding: 6px 18px;
    border-radius: 40px;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.25);
    font-size: 14px;
    letter-spacing: 2px;
    margin-bottom: 26px;
}

.hero-title {
    font-size: 46px;
    font-weight: 800;
    line-height: 1.3;
    margin-bottom: 20px;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

.hero-sub {
    font-size: 19px;
    color: rgba(255, 255, 255, 0.9);
    max-width: 720px;
    margin: 0 auto 34px;
}

.hero-meta {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 18px;
    margin-bottom: 44px;
}

.hero-meta .meta-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.12);
    border-radius: 10px;
    font-size: 15px;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 56px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 34px;
    border-radius: 40px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
    border: none;
}

.btn-primary {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.15);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.2);
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 2px solid rgba(255, 255, 255, 0.6);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.12);
    transform: translateY(-2px);
}

.hero-stats {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 40px;
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
}

.stat-item .stat-num {
    font-size: 36px;
    font-weight: 800;
    line-height: 1.2;
}

.stat-item .stat-label {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.85);
}

/* ---------------- 通用区块 ---------------- */
.section {
    padding: 90px 0;
}

.section.alt {
    background: var(--bg-white);
}

.section-header {
    text-align: center;
    max-width: 760px;
    margin: 0 auto 56px;
}

.section-header .kicker {
    display: inline-block;
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.section-header h2 {
    font-size: 36px;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 16px;
}

.section-header p {
    font-size: 16px;
    color: var(--text-sub);
}

/* ---------------- 展会介绍 About ---------------- */
.about-grid {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 56px;
    align-items: center;
}

.about-visual {
    position: relative;
}

.about-visual .visual-box {
    height: 420px;
    border-radius: 16px;
    background: linear-gradient(150deg, #0B7A75, #0E3A5C);
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(255, 255, 255, 0.9);
    font-size: 18px;
    font-weight: 600;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.visual-box::before {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 70% 30%, rgba(255, 255, 255, 0.18), transparent 45%);
}

.about-text h3 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 18px;
    color: var(--text-main);
}

.about-text p {
    font-size: 16px;
    color: var(--text-sub);
    margin-bottom: 16px;
}

.about-text ul {
    list-style: none;
    margin-top: 8px;
}

.about-text ul li {
    padding: 8px 0;
    padding-left: 26px;
    position: relative;
    font-size: 15px;
    color: var(--text-sub);
}

.about-text ul li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 16px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
}

/* 历届回顾 */
.recap-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 64px;
}

.recap-card {
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    background: var(--bg-white);
    transition: transform 0.3s, box-shadow 0.3s;
}

.recap-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.recap-img {
    height: 180px;
    background: linear-gradient(140deg, #12A89D, #0E3A5C);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 16px;
    font-weight: 600;
}

.recap-body {
    padding: 20px;
}

.recap-body h4 {
    font-size: 18px;
    margin-bottom: 8px;
}

.recap-body p {
    font-size: 14px;
    color: var(--text-sub);
}

/* ---------------- 参展招商 ---------------- */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 32px 26px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(11, 122, 117, 0.06);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 19px;
    margin-bottom: 10px;
    color: var(--text-main);
}

.feature-card p {
    font-size: 14px;
    color: var(--text-sub);
    margin-bottom: 16px;
}

.feature-card .learn-more {
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.cta-banner {
    margin-top: 48px;
    padding: 40px 48px;
    border-radius: 16px;
    background: linear-gradient(135deg, var(--primary-deep), var(--primary));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    flex-wrap: wrap;
    box-shadow: var(--shadow);
}

.cta-banner h3 {
    font-size: 24px;
    margin-bottom: 8px;
}

.cta-banner p {
    font-size: 15px;
    color: rgba(255, 255, 255, 0.9);
}

/* ---------------- 观众服务 ---------------- */
.visitor-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 48px;
    align-items: start;
}

.visitor-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.register-box {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 32px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(11, 122, 117, 0.06);
}

.register-box h3 {
    font-size: 20px;
    margin-bottom: 6px;
}

.register-box > p {
    font-size: 14px;
    color: var(--text-sub);
    margin-bottom: 22px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 14px;
    color: var(--text-main);
    font-weight: 500;
    margin-bottom: 6px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid #DDE6EA;
    border-radius: 8px;
    font-size: 15px;
    background: var(--bg-light);
    color: var(--text-main);
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus,
.form-group select:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(18, 168, 157, 0.15);
}

.form-submit {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    color: #fff;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.form-submit:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.form-tip {
    font-size: 12px;
    color: var(--text-sub);
    text-align: center;
    margin-top: 12px;
}

/* ---------------- 品牌形象 ---------------- */
.brand-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}

.brand-text h3 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 18px;
}

.brand-text p {
    font-size: 16px;
    color: var(--text-sub);
    margin-bottom: 16px;
}

.brand-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.brand-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 26px;
    box-shadow: var(--shadow);
    text-align: center;
}

.brand-card .brand-card-icon {
    width: 52px;
    height: 52px;
    margin: 0 auto 14px;
    border-radius: 12px;
    background: rgba(18, 168, 157, 0.12);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.brand-card h4 {
    font-size: 17px;
    margin-bottom: 8px;
}

.brand-card p {
    font-size: 13px;
    color: var(--text-sub);
}

/* ---------------- 软件产品（次要业务） ---------------- */
#software {
    background: var(--bg-white);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.product-card {
    text-align: center;
    padding: 36px 24px;
    border-radius: var(--radius);
    background: var(--bg-light);
    border: 1px solid rgba(11, 122, 117, 0.08);
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
}

.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    background: var(--bg-white);
}

.product-card .product-logo {
    width: 92px;
    height: 92px;
    margin: 0 auto 20px;
    border-radius: 22px;
    overflow: hidden;
    box-shadow: var(--shadow);
    background: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-card .product-logo img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.product-card h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: var(--text-main);
}

.product-card p {
    font-size: 14px;
    color: var(--text-sub);
}

.software-note {
    text-align: center;
    font-size: 14px;
    color: var(--text-sub);
    margin-top: 40px;
}

/* ---------------- 页脚 Footer ---------------- */
#footer {
    background: var(--bg-dark);
    color: #aab8c4;
    padding: 48px 0 0;
}

.footer-top {
    display: flex;
    justify-content: space-between;
    gap: 32px;
    flex-wrap: wrap;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand .footer-name {
    font-size: 20px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 8px;
}

.footer-brand p {
    font-size: 14px;
    max-width: 340px;
}

.footer-links {
    display: flex;
    gap: 60px;
    flex-wrap: wrap;
}

.footer-col h4 {
    color: #fff;
    font-size: 15px;
    margin-bottom: 14px;
}

.footer-col a {
    display: block;
    font-size: 14px;
    padding: 5px 0;
    color: #aab8c4;
    transition: color 0.2s;
}

.footer-col a:hover {
    color: var(--primary-light);
}

.footer-bottom {
    padding: 22px 0 30px;
    font-size: 13px;
    text-align: center;
}

.footer-bottom .links {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 8px;
}

.footer-bottom a {
    color: #aab8c4;
    text-decoration: underline;
}

.footer-bottom a:hover {
    color: var(--primary-light);
}

.footer-bottom .pub-icon {
    width: 15px;
    height: 15px;
    vertical-align: bottom;
    margin-bottom: 2px;
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 992px) {
    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-grid,
    .visitor-grid,
    .brand-grid {
        grid-template-columns: 1fr;
        gap: 36px;
    }
}

@media (max-width: 768px) {
    :root {
        --nav-height: 58px;
    }

    .hero-title {
        font-size: 32px;
    }

    .hero-sub {
        font-size: 16px;
    }

    .hero-content {
        padding: 80px 20px 90px;
    }

    .hero-stats {
        gap: 24px;
    }

    .stat-item .stat-num {
        font-size: 28px;
    }

    .section {
        padding: 60px 0;
    }

    .section-header h2 {
        font-size: 28px;
    }

    .nav-menu {
        position: fixed;
        top: var(--nav-height);
        right: -100%;
        width: 70%;
        max-width: 300px;
        height: calc(100vh - var(--nav-height));
        flex-direction: column;
        align-items: stretch;
        background: #fff;
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.1);
        padding: 24px 16px;
        gap: 4px;
        transition: right 0.3s ease;
        z-index: 1001;
    }

    .nav-menu.open {
        right: 0;
    }

    .nav-menu a {
        display: block;
        padding: 12px 16px;
        font-size: 16px;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.open span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .nav-toggle.open span:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.open span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    .recap-row,
    .product-grid {
        grid-template-columns: 1fr;
    }

    .visitor-cards {
        grid-template-columns: 1fr;
    }

    .cta-banner {
        flex-direction: column;
        text-align: center;
        padding: 32px 24px;
    }

    .btn {
        padding: 13px 26px;
        width: 100%;
        justify-content: center;
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
    }
}

@media (max-width: 560px) {
    .feature-grid,
    .brand-cards {
        grid-template-columns: 1fr;
    }

    .hero-meta {
        gap: 10px;
    }

    .footer-links {
        gap: 32px;
    }
}