/* roulang page: index */
:root {
            --primary: #0F172A;
            --primary-accent: #4338CA;
            --accent-green: #10B981;
            --accent-purple: #8B5CF6;
            --bg-light: #F8FAFC;
            --bg-white: #FFFFFF;
            --bg-slate: #F1F5F9;
            --bg-dark: #0B0F19;
            --text-main: #0F172A;
            --text-body: #475569;
            --text-muted: #94A3B8;
            --border-color: #E2E8F0;
            --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
            --shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
            --radius-card: 12px;
            --radius-pill: 9999px;
            --radius-input: 8px;
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-light);
            color: var(--text-body);
            line-height: 1.6;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
        }

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

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

        input, textarea, button, select {
            font-family: inherit;
        }

        .container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* Top Bar */
        .top-bar {
            background-color: var(--primary);
            color: #94A3B8;
            font-size: 13px;
            padding: 8px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        }

        .top-bar .container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 12px;
        }

        .top-bar-left, .top-bar-right {
            display: flex;
            align-items: center;
            gap: 20px;
        }

        /* Header Navigation */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background-color: rgba(255, 255, 255, 0.94);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-color);
        }

        .site-header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 76px;
        }

        .logo-wrap {
            display: flex;
            align-items: center;
            gap: 12px;
            font-size: 20px;
            font-weight: 800;
            color: var(--primary);
        }

        .logo-symbol {
            width: 38px;
            height: 38px;
            background: linear-gradient(135deg, var(--primary-accent), var(--accent-purple));
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-weight: 900;
            font-size: 18px;
            box-shadow: 0 4px 12px rgba(67, 56, 202, 0.3);
        }

        .nav-menu {
            display: flex;
            align-items: center;
            gap: 32px;
            list-style: none;
        }

        .nav-link {
            font-size: 15px;
            font-weight: 500;
            color: var(--text-main);
        }

        .nav-link:hover {
            color: var(--primary-accent);
        }

        .nav-btn {
            background-color: var(--primary-accent);
            color: #fff !important;
            padding: 10px 24px;
            border-radius: var(--radius-pill);
            font-size: 14px;
            font-weight: 600;
            box-shadow: 0 4px 14px rgba(67, 56, 202, 0.25);
            display: inline-block;
        }

        .nav-btn:hover {
            background-color: #3730A3;
            transform: translateY(-1px);
        }

        .mobile-menu-btn {
            display: none;
            background: none;
            border: none;
            font-size: 24px;
            color: var(--primary);
            cursor: pointer;
        }

        /* Section Layouts */
        .section {
            padding: 90px 0;
            position: relative;
        }

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

        .section-dark {
            background-color: var(--bg-dark);
            color: #E2E8F0;
        }

        .section-header {
            text-align: center;
            max-width: 820px;
            margin: 0 auto 56px;
        }

        .section-badge {
            display: inline-block;
            background-color: rgba(67, 56, 202, 0.1);
            color: var(--primary-accent);
            font-size: 13px;
            font-weight: 600;
            padding: 4px 14px;
            border-radius: var(--radius-pill);
            margin-bottom: 12px;
            letter-spacing: 0.5px;
        }

        .section-dark .section-badge {
            background-color: rgba(139, 92, 246, 0.2);
            color: #A78BFA;
        }

        .section-title {
            font-size: 32px;
            font-weight: 800;
            color: var(--text-main);
            margin-bottom: 16px;
            letter-spacing: -0.5px;
        }

        .section-dark .section-title {
            color: #FFFFFF;
        }

        .section-intro {
            font-size: 16px;
            color: var(--text-body);
            line-height: 1.7;
        }

        .section-dark .section-intro {
            color: #94A3B8;
        }

        /* Hero: 卡片堆叠首屏 (主卡+两张侧卡交错) */
        .hero-section {
            background-color: #F8FAFC;
            background-image: linear-gradient(180deg, rgba(241, 245, 249, 0.6) 0%, rgba(248, 250, 252, 1) 100%);
            padding: 70px 0 90px;
            overflow: hidden;
        }

        .hero-banner-inner {
            display: grid;
            grid-template-columns: 1fr;
            gap: 50px;
            align-items: center;
        }

        .hero-content {
            text-align: center;
            max-width: 840px;
            margin: 0 auto;
        }

        .hero-h1 {
            font-size: clamp(2.4rem, 4.5vw, 3.8rem);
            font-weight: 900;
            color: var(--text-main);
            line-height: 1.2;
            margin-bottom: 24px;
            letter-spacing: -1px;
        }

        .hero-h1 span {
            background: linear-gradient(135deg, var(--primary-accent), var(--accent-purple));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .hero-lead {
            font-size: 17px;
            color: var(--text-body);
            line-height: 1.8;
            margin-bottom: 36px;
        }

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

        .btn-primary {
            background-color: var(--primary-accent);
            color: #fff;
            padding: 14px 34px;
            border-radius: var(--radius-pill);
            font-weight: 600;
            font-size: 16px;
            box-shadow: 0 10px 20px rgba(67, 56, 202, 0.25);
            display: inline-block;
        }

        .btn-primary:hover {
            background-color: #3730A3;
            transform: translateY(-2px);
        }

        .btn-secondary {
            background-color: #fff;
            color: var(--text-main);
            border: 1px solid var(--border-color);
            padding: 14px 34px;
            border-radius: var(--radius-pill);
            font-weight: 600;
            font-size: 16px;
            display: inline-block;
        }

        .btn-secondary:hover {
            border-color: #CBD5E1;
            background-color: #F8FAFC;
        }

        /* Hero Stacking Cards */
        .hero-stack {
            display: flex;
            justify-content: center;
            align-items: center;
            position: relative;
            padding: 40px 0 20px;
        }

        .stack-card {
            background: #fff;
            border-radius: var(--radius-card);
            box-shadow: var(--shadow-hover);
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: var(--transition);
        }

        .stack-card-side {
            width: 320px;
            opacity: 0.85;
            filter: blur(0.5px);
            position: relative;
            z-index: 1;
        }

        .stack-card-left {
            transform: translateX(40px) scale(0.9) rotate(-3deg);
        }

        .stack-card-right {
            transform: translateX(-40px) scale(0.9) rotate(3deg);
        }

        .stack-card-main {
            width: 600px;
            position: relative;
            z-index: 2;
            transform: translateY(-10px);
            border-color: rgba(67, 56, 202, 0.3);
            box-shadow: 0 25px 50px -12px rgba(15, 23, 42, 0.25);
        }

        .stack-card:hover {
            transform: scale(0.98) translateY(-5px);
            opacity: 1;
            filter: none;
            z-index: 10;
        }

        .stack-thumb {
            width: 100%;
            height: 220px;
            object-fit: cover;
        }

        .stack-card-main .stack-thumb {
            height: 310px;
        }

        .stack-body {
            padding: 20px 24px;
        }

        .stack-meta {
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 12px;
            color: var(--text-muted);
            margin-bottom: 8px;
        }

        .stack-title {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 8px;
        }

        .stack-desc {
            font-size: 14px;
            color: var(--text-body);
            line-height: 1.5;
        }

        /* 倒计时与算力活动区 */
        .countdown-strip {
            background: linear-gradient(90deg, #0F172A 0%, #1E1B4B 100%);
            color: #fff;
            padding: 30px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }

        .countdown-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 24px;
        }

        .countdown-info {
            display: flex;
            align-items: center;
            gap: 16px;
        }

        .countdown-badge {
            background-color: var(--accent-green);
            color: #064E3B;
            font-weight: 700;
            font-size: 12px;
            padding: 4px 10px;
            border-radius: var(--radius-pill);
        }

        .countdown-label {
            font-size: 16px;
            font-weight: 600;
        }

        .timer-boxes {
            display: flex;
            gap: 12px;
            align-items: center;
        }

        .timer-unit {
            background-color: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(8px);
            padding: 10px 16px;
            border-radius: 8px;
            text-align: center;
            min-width: 60px;
            border: 1px solid rgba(255, 255, 255, 0.15);
        }

        .timer-num {
            font-size: 22px;
            font-weight: 800;
            color: #38BDF8;
            font-family: monospace;
        }

        .timer-text {
            font-size: 11px;
            color: #94A3B8;
            text-transform: uppercase;
        }

        /* 板块网格卡片系统 */
        .grid-3 {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }

        .grid-4 {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }

        .grid-2 {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 36px;
            align-items: center;
        }

        .card {
            background: var(--bg-white);
            border-radius: var(--radius-card);
            border: 1px solid var(--border-color);
            padding: 32px;
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
            display: flex;
            flex-direction: column;
            height: 100%;
        }

        .card:hover {
            box-shadow: var(--shadow-hover);
            transform: translateY(-4px);
            border-color: #CBD5E1;
        }

        .card-icon {
            width: 48px;
            height: 48px;
            border-radius: 10px;
            background-color: rgba(67, 56, 202, 0.1);
            color: var(--primary-accent);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            font-size: 20px;
            margin-bottom: 20px;
        }

        .card-title {
            font-size: 20px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 12px;
        }

        .card-text {
            font-size: 14.5px;
            color: var(--text-body);
            line-height: 1.65;
            flex-grow: 1;
        }

        .card-footer-meta {
            margin-top: 20px;
            padding-top: 16px;
            border-top: 1px solid var(--border-color);
            font-size: 13px;
            color: var(--text-muted);
            display: flex;
            justify-content: space-between;
        }

        /* 礼包与权益卡 */
        .benefit-card {
            border-top: 4px solid var(--primary-accent);
        }

        .benefit-card.highlight {
            border-top: 4px solid var(--accent-green);
            background: linear-gradient(180deg, #FFFFFF 0%, #F0FDF4 100%);
        }

        .benefit-tag {
            font-size: 12px;
            font-weight: 700;
            color: var(--accent-green);
            margin-bottom: 8px;
            text-transform: uppercase;
        }

        /* 玩法步骤流程 */
        .step-timeline {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 20px;
            position: relative;
        }

        .step-item {
            background: #fff;
            padding: 28px 24px;
            border-radius: var(--radius-card);
            border: 1px solid var(--border-color);
            position: relative;
            box-shadow: var(--shadow-sm);
        }

        .step-num {
            font-size: 32px;
            font-weight: 900;
            color: rgba(67, 56, 202, 0.15);
            line-height: 1;
            margin-bottom: 12px;
        }

        .step-name {
            font-size: 17px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 8px;
        }

        .step-desc {
            font-size: 13.5px;
            color: var(--text-body);
            line-height: 1.6;
        }

        /* 奖励与算力分配表格/卡片 */
        .reward-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }

        .reward-card {
            background: #fff;
            border-radius: var(--radius-card);
            padding: 32px;
            border: 1px solid var(--border-color);
            text-align: center;
            box-shadow: var(--shadow-sm);
        }

        .reward-badge {
            display: inline-block;
            padding: 4px 12px;
            font-size: 12px;
            font-weight: 700;
            border-radius: var(--radius-pill);
            background-color: #EEF2FF;
            color: var(--primary-accent);
            margin-bottom: 16px;
        }

        .reward-value {
            font-size: 36px;
            font-weight: 900;
            color: var(--text-main);
            margin-bottom: 8px;
            font-family: monospace;
        }

        .reward-param {
            font-size: 14px;
            color: var(--accent-green);
            font-weight: 600;
            margin-bottom: 16px;
        }

        .reward-desc {
            font-size: 14px;
            color: var(--text-body);
            line-height: 1.6;
        }

        /* 技术底座深色代码拓扑 */
        .tech-box {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            align-items: center;
        }

        .tech-code-panel {
            background-color: #030712;
            border-radius: var(--radius-card);
            border: 1px solid rgba(255, 255, 255, 0.1);
            padding: 24px;
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
            font-size: 13.5px;
            color: #38BDF8;
            overflow-x: auto;
            line-height: 1.7;
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
        }

        .tech-code-panel .kw { color: #F43F5E; }
        .tech-code-panel .fn { color: #A855F7; }
        .tech-code-panel .str { color: #10B981; }
        .tech-code-panel .cmt { color: #64748B; }

        /* 统计数据条 */
        .stats-bar {
            background-color: #fff;
            border-top: 1px solid var(--border-color);
            border-bottom: 1px solid var(--border-color);
            padding: 50px 0;
        }

        .stat-item {
            text-align: center;
        }

        .stat-number {
            font-size: clamp(2.2rem, 3.5vw, 3.2rem);
            font-weight: 900;
            color: var(--text-main);
            line-height: 1;
            margin-bottom: 8px;
            background: linear-gradient(135deg, var(--text-main), var(--primary-accent));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .stat-label {
            font-size: 14px;
            font-weight: 600;
            color: var(--text-muted);
        }

        /* 案例卡片 */
        .case-card {
            background: #fff;
            border-radius: var(--radius-card);
            overflow: hidden;
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-sm);
            display: grid;
            grid-template-columns: 1fr 1fr;
        }

        .case-image {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .case-content {
            padding: 40px;
            display: flex;
            flex-direction: column;
            justify-content: center;
        }

        .case-tag {
            font-size: 12px;
            font-weight: 700;
            color: var(--primary-accent);
            text-transform: uppercase;
            margin-bottom: 12px;
        }

        .case-title {
            font-size: 24px;
            font-weight: 800;
            color: var(--text-main);
            margin-bottom: 16px;
        }

        .case-comparison {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px;
            margin-top: 20px;
            background: var(--bg-slate);
            padding: 16px;
            border-radius: 8px;
        }

        .comp-item h5 {
            font-size: 13px;
            color: var(--text-muted);
            margin-bottom: 4px;
        }

        .comp-item p {
            font-size: 15px;
            font-weight: 700;
            color: var(--text-main);
        }

        /* 资讯网格 */
        .news-card {
            background: #fff;
            border-radius: var(--radius-card);
            overflow: hidden;
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
        }

        .news-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
        }

        .news-thumb {
            width: 100%;
            height: 190px;
            object-fit: cover;
        }

        .news-body {
            padding: 24px;
        }

        .news-date {
            font-size: 12px;
            color: var(--text-muted);
            margin-bottom: 8px;
            display: inline-block;
        }

        .news-title {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 10px;
            line-height: 1.4;
        }

        .news-desc {
            font-size: 13.5px;
            color: var(--text-body);
            line-height: 1.6;
        }

        /* 口碑评价卡 */
        .quote-card {
            background: #fff;
            border-radius: var(--radius-card);
            border: 1px solid var(--border-color);
            padding: 30px;
            box-shadow: var(--shadow-sm);
        }

        .quote-rating {
            color: #F59E0B;
            font-size: 16px;
            margin-bottom: 14px;
        }

        .quote-text {
            font-size: 14.5px;
            color: var(--text-body);
            line-height: 1.7;
            margin-bottom: 20px;
            font-style: italic;
        }

        .quote-author {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .author-avatar {
            width: 44px;
            height: 44px;
            border-radius: 50%;
            background-color: var(--bg-slate);
            border: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            color: var(--primary-accent);
        }

        .author-info h4 {
            font-size: 15px;
            font-weight: 700;
            color: var(--text-main);
        }

        .author-info p {
            font-size: 12px;
            color: var(--text-muted);
        }

        /* 报名与转化表单区 */
        .contact-box {
            background: #fff;
            border-radius: var(--radius-card);
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-hover);
            overflow: hidden;
            display: grid;
            grid-template-columns: 1fr 1.2fr;
        }

        .contact-side-info {
            background: linear-gradient(135deg, var(--primary) 0%, #1E1B4B 100%);
            color: #fff;
            padding: 48px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .contact-side-info h3 {
            font-size: 26px;
            font-weight: 800;
            margin-bottom: 16px;
        }

        .contact-side-info p {
            font-size: 15px;
            color: #94A3B8;
            line-height: 1.7;
            margin-bottom: 30px;
        }

        .contact-features-list {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .contact-features-list li {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 14px;
            color: #E2E8F0;
        }

        .contact-features-list span {
            color: var(--accent-green);
            font-weight: 900;
        }

        .contact-form-wrapper {
            padding: 48px;
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-label {
            display: block;
            font-size: 13.5px;
            font-weight: 600;
            color: var(--text-main);
            margin-bottom: 8px;
        }

        .form-control {
            width: 100%;
            padding: 12px 16px;
            border-radius: var(--radius-input);
            border: 1px solid var(--border-color);
            background-color: #F8FAFC;
            font-size: 14px;
            color: var(--text-main);
            outline: none;
            transition: var(--transition);
        }

        .form-control:focus {
            border-color: var(--primary-accent);
            background-color: #FFFFFF;
            box-shadow: 0 0 0 3px rgba(67, 56, 202, 0.15);
        }

        .form-submit-btn {
            width: 100%;
            background-color: var(--primary-accent);
            color: #fff;
            padding: 14px;
            border-radius: var(--radius-pill);
            border: none;
            font-size: 15px;
            font-weight: 700;
            cursor: pointer;
            transition: var(--transition);
            box-shadow: 0 4px 14px rgba(67, 56, 202, 0.3);
        }

        .form-submit-btn:hover {
            background-color: #3730A3;
            transform: translateY(-2px);
        }

        /* 常见解答 Accordion */
        .faq-accordion {
            max-width: 900px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .faq-item {
            background: #fff;
            border-radius: var(--radius-input);
            border: 1px solid var(--border-color);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
        }

        .faq-question {
            padding: 20px 24px;
            font-size: 16px;
            font-weight: 700;
            color: var(--text-main);
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            user-select: none;
            background: #fff;
            transition: var(--transition);
        }

        .faq-question:hover {
            background-color: #F8FAFC;
        }

        .faq-arrow {
            font-size: 14px;
            color: var(--text-muted);
            transition: transform 0.3s ease;
        }

        .faq-item.active .faq-arrow {
            transform: rotate(180deg);
            color: var(--primary-accent);
        }

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease;
            background-color: #FFFFFF;
        }

        .faq-answer-inner {
            padding: 0 24px 20px;
            font-size: 14.5px;
            color: var(--text-body);
            line-height: 1.7;
            border-top: 1px solid #F1F5F9;
            padding-top: 16px;
        }

        /* Footer */
        .site-footer {
            background-color: var(--primary);
            color: #94A3B8;
            padding: 80px 0 30px;
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            font-size: 14px;
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1.5fr;
            gap: 48px;
            margin-bottom: 60px;
        }

        .footer-logo {
            font-size: 22px;
            font-weight: 800;
            color: #FFFFFF;
            margin-bottom: 16px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .footer-desc {
            font-size: 14px;
            line-height: 1.7;
            color: #94A3B8;
            margin-bottom: 24px;
            max-width: 340px;
        }

        .footer-col-title {
            font-size: 15px;
            font-weight: 700;
            color: #FFFFFF;
            margin-bottom: 20px;
            letter-spacing: 0.5px;
        }

        .footer-links {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .footer-links a:hover {
            color: #FFFFFF;
            padding-left: 4px;
        }

        .footer-bottom {
            padding-top: 30px;
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 16px;
            font-size: 13px;
        }

        /* 移动端断点适配 */
        @media (max-width: 1024px) {
            .grid-4 { grid-template-columns: repeat(2, 1fr); }
            .step-timeline { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: repeat(2, 1fr); gap: 32px; }
            .tech-box { grid-template-columns: 1fr; }
            .case-card { grid-template-columns: 1fr; }
            .contact-box { grid-template-columns: 1fr; }
        }

        @media (max-width: 768px) {
            .mobile-menu-btn { display: block; }
            .nav-menu {
                position: fixed;
                top: 76px;
                left: 0;
                width: 100%;
                background-color: #FFFFFF;
                flex-direction: column;
                padding: 30px 24px;
                gap: 20px;
                box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
                border-bottom: 1px solid var(--border-color);
                display: none;
            }
            .nav-menu.open { display: flex; }
            .hero-stack {
                flex-direction: column;
                gap: 20px;
            }
            .stack-card-side { display: none; }
            .stack-card-main { width: 100%; transform: none; }
            .grid-3 { grid-template-columns: 1fr; }
            .grid-4 { grid-template-columns: 1fr; }
            .grid-2 { grid-template-columns: 1fr; }
            .reward-grid { grid-template-columns: 1fr; }
            .step-timeline { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; }
            .top-bar-left, .top-bar-right { font-size: 12px; }
            .section { padding: 60px 0; }
        }