/* roulang page: index */
:root {
            --primary: #1B6EC2;
            --primary-hover: #155A9E;
            --primary-light: #EBF3FA;
            --accent: #E67E22;
            --accent-light: #FFF3E0;
            --bg: #F5F7FA;
            --white: #FFFFFF;
            --text: #2D3748;
            --text-secondary: #4A5568;
            --text-muted: #718096;
            --border: #E2E8F0;
            --border-light: #E0E0E0;
            --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.06);
            --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.1);
            --shadow-top: 0 -2px 8px rgba(0, 0, 0, 0.05);
            --radius-sm: 6px;
            --radius-md: 8px;
            --radius-lg: 12px;
            --radius-pill: 24px;
            --radius-full: 50%;
            --font-stack: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
            --transition: 0.2s ease;
            --nav-height: 60px;
            --container-max: 1200px;
            --section-gap: 80px;
        }

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

        html {
            scroll-behavior: smooth;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: var(--font-stack);
            font-size: 1rem;
            line-height: 1.6;
            color: var(--text);
            background-color: var(--bg);
            min-height: 100vh;
            padding-top: var(--nav-height);
            padding-bottom: 70px;
        }

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

        a {
            color: var(--primary);
            text-decoration: none;
            transition: color var(--transition), text-decoration var(--transition);
        }
        a:hover {
            color: var(--primary-hover);
            text-decoration: underline;
        }
        a:focus-visible {
            outline: 2px solid var(--primary);
            outline-offset: 2px;
            border-radius: 2px;
        }

        button {
            cursor: pointer;
            font-family: inherit;
            border: none;
            background: none;
            transition: all var(--transition);
        }
        button:focus-visible {
            outline: 2px solid var(--primary);
            outline-offset: 2px;
            border-radius: var(--radius-md);
        }

        input {
            font-family: inherit;
            transition: border var(--transition), box-shadow var(--transition);
        }
        input:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(27, 110, 194, 0.2);
        }

        ul {
            list-style: none;
        }

        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 20px;
        }

        .section {
            padding: var(--section-gap) 0;
        }
        .section--sm {
            padding: 48px 0;
        }
        .section--hero {
            padding: 80px 0 60px;
        }
        .section--bg-white {
            background-color: var(--white);
        }
        .section--bg-light {
            background-color: var(--bg);
        }

        .section__header {
            text-align: center;
            margin-bottom: 48px;
        }
        .section__title {
            font-size: 2rem;
            font-weight: 700;
            color: #1A202C;
            line-height: 1.3;
            margin-bottom: 12px;
        }
        .section__subtitle {
            font-size: 1rem;
            color: var(--text-secondary);
            max-width: 640px;
            margin: 0 auto;
            line-height: 1.6;
        }

        /* ========== 导航栏 ========== */
        .nav {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--nav-height);
            background: var(--white);
            border-bottom: 1px solid var(--border-light);
            z-index: 1000;
            display: flex;
            align-items: center;
            transition: box-shadow var(--transition);
        }
        .nav.scrolled {
            box-shadow: 0 2px 16px rgba(0, 0, 0, 0.08);
        }
        .nav__inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 20px;
            height: 100%;
        }
        .nav__logo {
            font-size: 1.25rem;
            font-weight: 700;
            color: var(--primary);
            white-space: nowrap;
            letter-spacing: 0.02em;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .nav__logo:hover {
            color: var(--primary-hover);
            text-decoration: none;
        }
        .nav__logo-icon {
            width: 32px;
            height: 32px;
            flex-shrink: 0;
        }
        .nav__menu {
            display: flex;
            align-items: center;
            gap: 28px;
            list-style: none;
        }
        .nav__menu a {
            font-size: 1rem;
            color: var(--text);
            font-weight: 500;
            text-decoration: none;
            white-space: nowrap;
            transition: color var(--transition);
            position: relative;
            padding: 4px 0;
        }
        .nav__menu a:hover,
        .nav__menu a.active {
            color: var(--primary);
            text-decoration: none;
        }
        .nav__menu a.active::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 100%;
            height: 2px;
            background: var(--primary);
            border-radius: 1px;
        }
        .nav__menu-item {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .chip {
            display: inline-flex;
            align-items: center;
            height: 24px;
            padding: 0 10px;
            font-size: 0.75rem;
            font-weight: 600;
            border-radius: var(--radius-pill);
            white-space: nowrap;
            letter-spacing: 0.02em;
            transition: transform var(--transition);
        }
        .chip--live {
            background: #FFF3E0;
            color: #E67E22;
            border: 1px solid #E67E22;
        }
        .chip--upcoming {
            background: #E8F4FD;
            color: #1B6EC2;
            border: 1px solid #1B6EC2;
        }
        .chip--past {
            background: #F7FAFC;
            color: #718096;
            border: 1px solid #CBD5E0;
        }
        .chip:hover {
            transform: scale(1.05);
        }
        .nav__hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            width: 28px;
            height: 22px;
            justify-content: center;
            cursor: pointer;
            z-index: 1001;
            background: none;
            border: none;
            padding: 0;
        }
        .nav__hamburger span {
            display: block;
            width: 100%;
            height: 2px;
            background: var(--text);
            border-radius: 2px;
            transition: all var(--transition);
        }
        .nav__hamburger.active span:nth-child(1) {
            transform: rotate(45deg) translate(5px, 5px);
        }
        .nav__hamburger.active span:nth-child(2) {
            opacity: 0;
        }
        .nav__hamburger.active span:nth-child(3) {
            transform: rotate(-45deg) translate(5px, -5px);
        }

        @media (max-width: 768px) {
            .nav__hamburger {
                display: flex;
            }
            .nav__menu {
                position: fixed;
                top: var(--nav-height);
                left: 0;
                width: 100%;
                background: var(--white);
                flex-direction: column;
                gap: 0;
                padding: 16px 20px;
                border-bottom: 1px solid var(--border-light);
                box-shadow: var(--shadow-md);
                transform: translateY(-120%);
                opacity: 0;
                pointer-events: none;
                transition: all 0.3s ease;
                z-index: 999;
            }
            .nav__menu.open {
                transform: translateY(0);
                opacity: 1;
                pointer-events: auto;
            }
            .nav__menu li {
                padding: 12px 0;
                border-bottom: 1px solid var(--border);
            }
            .nav__menu li:last-child {
                border-bottom: none;
            }
            .nav__menu-item {
                flex-wrap: wrap;
                gap: 8px;
            }
        }

        /* ========== Hero 限时活动报名 ========== */
        .hero {
            background: linear-gradient(160deg, #EBF3FA 0%, #F5F7FA 40%, #FFFFFF 100%);
            position: relative;
            overflow: hidden;
            padding: 72px 0 64px;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            right: 0;
            width: 45%;
            height: 100%;
            background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
            opacity: 0.18;
            pointer-events: none;
            border-radius: 0 0 0 60px;
        }
        .hero__inner {
            position: relative;
            z-index: 1;
            display: flex;
            align-items: center;
            gap: 48px;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 20px;
        }
        .hero__content {
            flex: 1;
            min-width: 0;
        }
        .hero__badge {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: #FFF3E0;
            color: #E67E22;
            font-weight: 700;
            font-size: 0.9rem;
            padding: 8px 16px;
            border-radius: var(--radius-pill);
            margin-bottom: 20px;
            letter-spacing: 0.03em;
            animation: pulse-badge 2s ease-in-out infinite;
        }
        @keyframes pulse-badge {
            0%,
            100% {
                box-shadow: 0 0 0 0 rgba(230, 126, 34, 0.35);
            }
            50% {
                box-shadow: 0 0 0 12px rgba(230, 126, 34, 0);
            }
        }
        .hero__badge-dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: #E67E22;
            animation: blink-dot 1s ease-in-out infinite;
        }
        @keyframes blink-dot {
            0%,
            100% {
                opacity: 1;
            }
            50% {
                opacity: 0.3;
            }
        }
        .hero__title {
            font-size: 2.5rem;
            font-weight: 700;
            color: #1A202C;
            line-height: 1.25;
            margin-bottom: 16px;
            letter-spacing: 0.01em;
        }
        .hero__desc {
            font-size: 1rem;
            color: var(--text-secondary);
            line-height: 1.7;
            margin-bottom: 12px;
            max-width: 540px;
        }
        .hero__countdown-wrap {
            display: flex;
            align-items: center;
            gap: 16px;
            margin-bottom: 24px;
            flex-wrap: wrap;
        }
        .hero__countdown-label {
            font-size: 0.9rem;
            font-weight: 600;
            color: var(--text);
        }
        .hero__countdown {
            display: flex;
            gap: 8px;
        }
        .hero__countdown-item {
            background: #1A202C;
            color: #fff;
            font-weight: 700;
            font-size: 1.25rem;
            padding: 8px 13px;
            border-radius: var(--radius-md);
            min-width: 48px;
            text-align: center;
            letter-spacing: 0.04em;
            line-height: 1;
        }
        .hero__countdown-sep {
            font-size: 1.25rem;
            font-weight: 700;
            color: #1A202C;
            align-self: center;
        }
        .hero__cta-group {
            display: flex;
            gap: 16px;
            flex-wrap: wrap;
        }
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            font-size: 1rem;
            font-weight: 600;
            padding: 12px 28px;
            border-radius: var(--radius-md);
            cursor: pointer;
            transition: all var(--transition);
            white-space: nowrap;
            letter-spacing: 0.02em;
            text-decoration: none;
            border: 2px solid transparent;
            line-height: 1.4;
        }
        .btn:active {
            transform: scale(0.98);
        }
        .btn--primary {
            background: var(--primary);
            color: #fff;
            border-color: var(--primary);
            box-shadow: 0 4px 14px rgba(27, 110, 194, 0.3);
        }
        .btn--primary:hover {
            background: var(--primary-hover);
            border-color: var(--primary-hover);
            box-shadow: 0 6px 20px rgba(27, 110, 194, 0.4);
            text-decoration: none;
            color: #fff;
        }
        .btn--outline {
            background: transparent;
            color: var(--primary);
            border-color: var(--primary);
        }
        .btn--outline:hover {
            background: var(--primary-light);
            text-decoration: none;
            color: var(--primary);
        }
        .btn--lg {
            font-size: 1.1rem;
            padding: 14px 36px;
            font-weight: 700;
        }
        .btn--accent {
            background: var(--accent);
            color: #fff;
            border-color: var(--accent);
            box-shadow: 0 4px 14px rgba(230, 126, 34, 0.3);
        }
        .btn--accent:hover {
            background: #d4701a;
            border-color: #d4701a;
            box-shadow: 0 6px 20px rgba(230, 126, 34, 0.4);
            text-decoration: none;
            color: #fff;
        }
        .hero__card {
            flex: 0 0 380px;
            background: var(--white);
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow-md);
            padding: 28px;
            position: relative;
            overflow: hidden;
            max-width: 380px;
        }
        .hero__card-tag {
            position: absolute;
            top: 16px;
            right: 16px;
            background: #E53E3E;
            color: #fff;
            font-size: 0.75rem;
            font-weight: 700;
            padding: 5px 12px;
            border-radius: var(--radius-pill);
            letter-spacing: 0.03em;
        }
        .hero__card-img {
            width: 100%;
            height: 180px;
            object-fit: cover;
            border-radius: var(--radius-md);
            margin-bottom: 16px;
        }
        .hero__card-title {
            font-size: 1.25rem;
            font-weight: 700;
            color: #1A202C;
            margin-bottom: 8px;
        }
        .hero__card-info {
            font-size: 0.9rem;
            color: var(--text-secondary);
            margin-bottom: 6px;
            line-height: 1.5;
        }
        .hero__card-meta {
            display: flex;
            gap: 16px;
            font-size: 0.8rem;
            color: var(--text-muted);
            margin-bottom: 16px;
            flex-wrap: wrap;
        }
        .hero__card .btn {
            width: 100%;
        }

        @media (max-width: 1024px) {
            .hero__inner {
                flex-direction: column;
                gap: 32px;
            }
            .hero__card {
                flex: 0 0 auto;
                max-width: 100%;
                width: 100%;
            }
            .hero__title {
                font-size: 2rem;
            }
            .hero::before {
                width: 100%;
                opacity: 0.08;
                border-radius: 0;
            }
        }
        @media (max-width: 640px) {
            .hero {
                padding: 48px 0 40px;
            }
            .hero__title {
                font-size: 1.6rem;
            }
            .hero__countdown-item {
                font-size: 1rem;
                padding: 6px 10px;
                min-width: 38px;
            }
            .hero__cta-group {
                flex-direction: column;
                gap: 10px;
            }
            .btn {
                width: 100%;
                justify-content: center;
            }
            .hero__card {
                padding: 20px;
            }
            .hero__card-img {
                height: 140px;
            }
        }

        /* ========== 爆款清单 ========== */
        .hotlist {
            background: var(--white);
        }
        .hotlist__grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 20px;
        }
        .hotlist__item {
            background: var(--bg);
            border-radius: var(--radius-lg);
            padding: 24px;
            position: relative;
            transition: all var(--transition);
            border: 1px solid transparent;
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .hotlist__item:hover {
            box-shadow: var(--shadow-md);
            border-color: var(--border);
            transform: translateY(-2px);
        }
        .hotlist__rank {
            font-size: 2.5rem;
            font-weight: 800;
            color: var(--primary);
            opacity: 0.3;
            line-height: 1;
            position: absolute;
            top: 16px;
            right: 20px;
        }
        .hotlist__icon {
            width: 48px;
            height: 48px;
            border-radius: var(--radius-md);
            object-fit: cover;
            flex-shrink: 0;
        }
        .hotlist__title {
            font-size: 1.1rem;
            font-weight: 700;
            color: #1A202C;
            line-height: 1.3;
        }
        .hotlist__desc {
            font-size: 0.875rem;
            color: var(--text-secondary);
            line-height: 1.5;
            flex-grow: 1;
        }
        .hotlist__link {
            font-size: 0.9rem;
            font-weight: 600;
            color: var(--primary);
            display: inline-flex;
            align-items: center;
            gap: 4px;
            margin-top: auto;
        }
        .hotlist__link:hover {
            text-decoration: underline;
        }
        @media (max-width: 1024px) {
            .hotlist__grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 640px) {
            .hotlist__grid {
                grid-template-columns: 1fr;
            }
        }

        /* ========== 最新动态 ========== */
        .news {
            background: var(--bg);
        }
        .news__list {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px 32px;
            max-width: 900px;
            margin: 0 auto;
        }
        .news__item {
            display: flex;
            align-items: baseline;
            gap: 12px;
            padding: 12px 0;
            border-bottom: 1px solid var(--border);
            transition: all var(--transition);
        }
        .news__item:hover {
            border-bottom-color: var(--primary);
        }
        .news__item-date {
            font-size: 0.8rem;
            color: var(--text-muted);
            white-space: nowrap;
            flex-shrink: 0;
        }
        .news__item-title {
            font-size: 0.95rem;
            color: var(--text);
            font-weight: 500;
            line-height: 1.5;
            transition: color var(--transition);
        }
        .news__item:hover .news__item-title {
            color: var(--primary);
        }
        .news__item a {
            text-decoration: none;
            color: inherit;
            display: contents;
        }
        @media (max-width: 640px) {
            .news__list {
                grid-template-columns: 1fr;
            }
        }

        /* ========== 场景演示 ========== */
        .demo {
            background: var(--white);
        }
        .demo__inner {
            display: flex;
            align-items: center;
            gap: 56px;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 20px;
        }
        .demo__image {
            flex: 0 0 48%;
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-md);
        }
        .demo__image img {
            width: 100%;
            height: auto;
            display: block;
        }
        .demo__content {
            flex: 1;
            min-width: 0;
        }
        .demo__content h2 {
            font-size: 1.75rem;
            font-weight: 700;
            color: #1A202C;
            margin-bottom: 16px;
            line-height: 1.3;
        }
        .demo__content p {
            font-size: 1rem;
            color: var(--text-secondary);
            line-height: 1.7;
            margin-bottom: 16px;
        }
        .demo__list {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .demo__list li {
            font-size: 0.95rem;
            color: var(--text);
            padding-left: 24px;
            position: relative;
            line-height: 1.5;
        }
        .demo__list li::before {
            content: '';
            position: absolute;
            left: 0;
            top: 8px;
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--primary);
        }
        @media (max-width: 1024px) {
            .demo__inner {
                flex-direction: column;
                gap: 32px;
            }
            .demo__image {
                flex: 0 0 auto;
                width: 100%;
            }
        }

        /* ========== 渠道卖点：三步上手 ========== */
        .steps {
            background: var(--bg);
        }
        .steps__grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }
        .steps__card {
            background: var(--white);
            border-radius: var(--radius-lg);
            padding: 32px 24px;
            text-align: center;
            box-shadow: var(--shadow-sm);
            transition: all var(--transition);
            position: relative;
        }
        .steps__card:hover {
            box-shadow: var(--shadow-md);
            transform: translateY(-4px);
        }
        .steps__num {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 48px;
            height: 48px;
            border-radius: var(--radius-full);
            background: var(--primary);
            color: #fff;
            font-size: 1.3rem;
            font-weight: 700;
            margin-bottom: 16px;
        }
        .steps__card h3 {
            font-size: 1.15rem;
            font-weight: 700;
            color: #1A202C;
            margin-bottom: 8px;
        }
        .steps__card p {
            font-size: 0.9rem;
            color: var(--text-secondary);
            line-height: 1.6;
        }
        .steps__faq {
            margin-top: 40px;
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 16px;
        }
        .steps__faq-item {
            background: var(--white);
            border-radius: var(--radius-md);
            padding: 16px 20px;
            border-left: 3px solid var(--primary);
            font-size: 0.9rem;
            color: var(--text);
            line-height: 1.5;
        }
        .steps__faq-item strong {
            display: block;
            margin-bottom: 4px;
            color: #1A202C;
            font-size: 0.95rem;
        }
        @media (max-width: 768px) {
            .steps__grid {
                grid-template-columns: 1fr;
            }
            .steps__faq {
                grid-template-columns: 1fr;
            }
        }

        /* ========== 快速解答 FAQ ========== */
        .faq {
            background: var(--white);
        }
        .faq__list {
            max-width: 760px;
            margin: 0 auto;
        }
        .faq__item {
            border-bottom: 1px solid var(--border);
            transition: all var(--transition);
        }
        .faq__question {
            width: 100%;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 16px;
            padding: 18px 0;
            font-size: 1rem;
            font-weight: 600;
            color: #1A202C;
            cursor: pointer;
            background: none;
            border: none;
            text-align: left;
            line-height: 1.5;
            transition: color var(--transition);
        }
        .faq__question:hover {
            color: var(--primary);
        }
        .faq__icon {
            flex-shrink: 0;
            width: 20px;
            height: 20px;
            transition: transform var(--transition);
            position: relative;
        }
        .faq__icon::before,
        .faq__icon::after {
            content: '';
            position: absolute;
            background: var(--text);
            border-radius: 2px;
            transition: all var(--transition);
        }
        .faq__icon::before {
            width: 100%;
            height: 2px;
            top: 50%;
            left: 0;
            transform: translateY(-50%);
        }
        .faq__icon::after {
            width: 2px;
            height: 100%;
            left: 50%;
            top: 0;
            transform: translateX(-50%);
        }
        .faq__item.open .faq__icon::after {
            transform: translateX(-50%) rotate(90deg);
        }
        .faq__answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.35s ease;
        }
        .faq__item.open .faq__answer {
            max-height: 300px;
            padding-bottom: 18px;
        }
        .faq__answer p {
            font-size: 0.9rem;
            color: var(--text-secondary);
            line-height: 1.7;
        }

        /* ========== 资讯区 ========== */
        .info {
            background: var(--bg);
        }
        .info__inner {
            display: flex;
            gap: 32px;
            align-items: flex-start;
        }
        .info__list {
            flex: 1;
            min-width: 0;
        }
        .info__list-item {
            display: flex;
            align-items: baseline;
            gap: 14px;
            padding: 14px 0;
            border-bottom: 1px solid var(--border);
            transition: all var(--transition);
        }
        .info__list-item:hover {
            border-bottom-color: var(--primary);
        }
        .info__list-date {
            font-size: 0.8rem;
            color: var(--text-muted);
            white-space: nowrap;
            flex-shrink: 0;
        }
        .info__list-title {
            font-size: 0.95rem;
            font-weight: 500;
            color: var(--text);
            line-height: 1.5;
            transition: color var(--transition);
        }
        .info__list-item:hover .info__list-title {
            color: var(--primary);
        }
        .info__list-item a {
            text-decoration: none;
            color: inherit;
            display: contents;
        }
        .info__sidebar {
            flex: 0 0 300px;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        .info__sidebar-card {
            background: var(--white);
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
            transition: all var(--transition);
        }
        .info__sidebar-card:hover {
            box-shadow: var(--shadow-md);
        }
        .info__sidebar-card img {
            width: 100%;
            height: 140px;
            object-fit: cover;
        }
        .info__sidebar-card-body {
            padding: 16px;
        }
        .info__sidebar-card-body h4 {
            font-size: 0.95rem;
            font-weight: 600;
            color: #1A202C;
            margin-bottom: 6px;
            line-height: 1.4;
        }
        .info__sidebar-card-body p {
            font-size: 0.8rem;
            color: var(--text-muted);
            line-height: 1.5;
        }
        @media (max-width: 768px) {
            .info__inner {
                flex-direction: column;
            }
            .info__sidebar {
                flex: 0 0 auto;
                width: 100%;
                flex-direction: row;
                flex-wrap: wrap;
            }
            .info__sidebar-card {
                flex: 0 0 calc(50% - 8px);
                min-width: 140px;
            }
        }
        @media (max-width: 520px) {
            .info__sidebar-card {
                flex: 0 0 100%;
            }
        }

        /* ========== 安全体系 ========== */
        .security {
            background: var(--white);
        }
        .security__grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }
        .security__card {
            text-align: center;
            padding: 28px 20px;
            border-radius: var(--radius-lg);
            background: var(--bg);
            transition: all var(--transition);
            border: 1px solid transparent;
        }
        .security__card:hover {
            box-shadow: var(--shadow-md);
            border-color: var(--border);
            transform: translateY(-2px);
        }
        .security__icon {
            width: 56px;
            height: 56px;
            margin: 0 auto 16px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: var(--radius-full);
            background: var(--primary-light);
        }
        .security__icon svg {
            width: 28px;
            height: 28px;
            color: var(--primary);
        }
        .security__card h3 {
            font-size: 1.05rem;
            font-weight: 700;
            color: #1A202C;
            margin-bottom: 8px;
        }
        .security__card p {
            font-size: 0.85rem;
            color: var(--text-secondary);
            line-height: 1.6;
        }
        @media (max-width: 1024px) {
            .security__grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 520px) {
            .security__grid {
                grid-template-columns: 1fr;
            }
        }

        /* ========== 底部固定转化条 ========== */
        .sticky-cta {
            position: fixed;
            bottom: 0;
            left: 0;
            width: 100%;
            background: var(--white);
            box-shadow: var(--shadow-top);
            z-index: 998;
            padding: 10px 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 20px;
            min-height: 56px;
            flex-wrap: wrap;
        }
        .sticky-cta__text {
            font-size: 0.95rem;
            font-weight: 600;
            color: #1A202C;
            white-space: nowrap;
        }
        .sticky-cta .btn {
            flex-shrink: 0;
        }
        @media (max-width: 520px) {
            .sticky-cta {
                flex-direction: column;
                gap: 8px;
                padding: 8px 16px;
                min-height: auto;
            }
            .sticky-cta__text {
                font-size: 0.85rem;
                white-space: normal;
                text-align: center;
            }
            .sticky-cta .btn {
                width: 100%;
            }
        }

        /* ========== 页脚 ========== */
        .footer {
            background: #F5F7FA;
            padding: 48px 0 24px;
            border-top: 1px solid var(--border);
        }
        .footer__grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 32px;
            margin-bottom: 32px;
        }
        .footer__col h4 {
            font-size: 0.9rem;
            font-weight: 700;
            color: #1A202C;
            margin-bottom: 14px;
            letter-spacing: 0.02em;
        }
        .footer__col ul {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .footer__col a {
            font-size: 0.85rem;
            color: var(--text-secondary);
            text-decoration: none;
            transition: color var(--transition);
        }
        .footer__col a:hover {
            color: var(--primary);
            text-decoration: underline;
        }
        .footer__bottom {
            text-align: center;
            padding-top: 20px;
            border-top: 1px solid var(--border);
            font-size: 0.8rem;
            color: var(--text-muted);
            line-height: 1.6;
        }
        @media (max-width: 768px) {
            .footer__grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 520px) {
            .footer__grid {
                grid-template-columns: 1fr;
            }
        }

        /* ========== 通用工具类 ========== */
        .sr-only {
            position: absolute;
            width: 1px;
            height: 1px;
            padding: 0;
            margin: -1px;
            overflow: hidden;
            clip: rect(0, 0, 0, 0);
            white-space: nowrap;
            border: 0;
        }
        .text-accent {
            color: var(--accent);
        }
        .text-primary {
            color: var(--primary);
        }
        .fw-700 {
            font-weight: 700;
        }