/* ===========================
   龙诚科技 - 官方样式表
   主色调：深蓝 + 科技蓝 + 橙色 + 红色
   =========================== */

/* --- CSS 变量 --- */
:root {
    --color-primary: #0B2545;
    --color-primary-light: #13315C;
    --color-accent-blue: #1B98E0;
    --color-accent-orange: #F26430;
    --color-accent-red: #E63946;
    --color-text: #1a1a2e;
    --color-text-light: #4a4a68;
    --color-text-muted: #8b8ba7;
    --color-border: #e6e8ef;
    --color-bg: #ffffff;
    --color-bg-soft: #f7f9fc;
    --color-bg-dark: #0a0e1a;
    --gradient-primary: linear-gradient(135deg, #0B2545 0%, #13315C 50%, #1B98E0 100%);
    --gradient-accent: linear-gradient(135deg, #F26430 0%, #E63946 100%);
    --gradient-logo: linear-gradient(135deg, #FFD700 0%, #F26430 30%, #E63946 60%, #1B98E0 100%);
    --shadow-sm: 0 2px 8px rgba(11, 37, 69, 0.06);
    --shadow-md: 0 4px 20px rgba(11, 37, 69, 0.08);
    --shadow-lg: 0 12px 40px rgba(11, 37, 69, 0.12);
    --shadow-xl: 0 24px 60px rgba(11, 37, 69, 0.18);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --max-width: 1200px;
    --font-cn: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
    --font-en: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-cn);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
ul, ol { list-style: none; }
input, textarea, select { font-family: inherit; font-size: inherit; }

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ===========================
   导航栏
   =========================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 16px 0;
    transition: all var(--transition);
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
}

.navbar.scrolled {
    padding: 10px 0;
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-sm);
    border-bottom-color: var(--color-border);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.logo-icon {
    width: 56px;
    height: 48px;
    object-fit: contain;
    filter: drop-shadow(0 2px 6px rgba(11, 37, 69, 0.2));
}

.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}

.logo-name {
    font-size: 18px;
    font-weight: 800;
    color: var(--color-primary);
    letter-spacing: 1px;
}

.logo-en {
    font-family: var(--font-en);
    font-size: 9px;
    color: var(--color-text-muted);
    letter-spacing: 1.5px;
    font-weight: 500;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    font-size: 15px;
    font-weight: 500;
    color: var(--color-text);
    border-radius: var(--radius-sm);
    transition: all var(--transition);
    position: relative;
}

.nav-link-mega {
    font-size: 13px;
    padding: 8px 12px;
    font-weight: 600;
    color: var(--color-primary);
    line-height: 1.4;
    max-width: 280px;
}

.nav-link:hover {
    color: var(--color-primary);
    background: var(--color-bg-soft);
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 3px;
    background: var(--gradient-accent);
    border-radius: 2px;
}

.nav-cta {
    margin-left: 12px;
    padding: 10px 22px;
    font-size: 14px;
    font-weight: 600;
    color: white;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    transition: all var(--transition);
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(11, 37, 69, 0.3);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 2px;
    transition: all var(--transition);
}

/* ===========================
   Hero
   =========================== */
.hero {
    position: relative;
    min-height: 100vh;
    padding: 140px 0 80px;
    display: flex;
    align-items: center;
    overflow: hidden;
    background: var(--color-bg-dark);
    color: white;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 1;
    pointer-events: none;
}

.hero-bg-gradient {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at top left, rgba(27, 152, 224, 0.25) 0%, transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(242, 100, 48, 0.2) 0%, transparent 50%),
        linear-gradient(180deg, #0a0e1a 0%, #0B2545 100%);
}

.hero-bg-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 80%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 80%);
}

.hero-bg-glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
}

.hero-bg-glow-1 {
    width: 400px;
    height: 400px;
    background: var(--color-accent-blue);
    top: 10%;
    right: 10%;
    animation: float 8s ease-in-out infinite;
}

.hero-bg-glow-2 {
    width: 300px;
    height: 300px;
    background: var(--color-accent-orange);
    bottom: 10%;
    left: 10%;
    animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(40px, -40px); }
}

.hero-content {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-text { animation: fadeInUp 1s ease 0.2s both; }

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 100px;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 28px;
    backdrop-filter: blur(10px);
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: #00ff88;
    border-radius: 50%;
    box-shadow: 0 0 10px #00ff88;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(0.9); }
}

.hero-title {
    font-size: clamp(40px, 6vw, 72px);
    font-weight: 900;
    line-height: 1.1;
    letter-spacing: -1px;
    margin-bottom: 24px;
}

.gradient-text {
    background: linear-gradient(135deg, #FFD700 0%, #F26430 40%, #E63946 70%, #1B98E0 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    background-size: 200% auto;
    animation: gradient-shift 4s ease infinite;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-subtitle {
    font-size: clamp(16px, 1.5vw, 19px);
    color: rgba(255, 255, 255, 0.75);
    margin-bottom: 36px;
    max-width: 540px;
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 15px;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all var(--transition);
    cursor: pointer;
}

.btn-primary {
    background: var(--gradient-accent);
    color: white;
    box-shadow: 0 8px 24px rgba(242, 100, 48, 0.35);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 32px rgba(242, 100, 48, 0.5);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.25);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.18);
    transform: translateY(-3px);
}

.btn-arrow {
    transition: transform var(--transition);
}

.btn:hover .btn-arrow {
    transform: translateX(4px);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 24px;
    padding-top: 32px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    max-width: 480px;
}

.stat-item { flex: 1; }
.stat-num {
    font-size: 32px;
    font-weight: 800;
    background: linear-gradient(135deg, #ffffff 0%, #1B98E0 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    line-height: 1.2;
}

.stat-label {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.6);
    margin-top: 4px;
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: rgba(255, 255, 255, 0.15);
}

/* Hero 右侧装饰卡片 */
.hero-visual {
    position: relative;
    height: 480px;
    max-width: 460px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
    gap: 20px;
    animation: fadeIn 1s ease 0.5s both;
}

.hero-card {
    position: relative;
    padding: 24px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(20px);
    transition: all var(--transition);
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 200px;
}

.hero-card:hover {
    transform: translateY(-8px) scale(1.03);
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.25);
}

.hero-card-1 {
    animation: float-card 6s ease-in-out infinite;
}

.hero-card-2 {
    animation: float-card 6s ease-in-out infinite 1.5s;
}

.hero-card-3 {
    animation: float-card 6s ease-in-out infinite 3s;
}

.hero-card-4 {
    animation: float-card 6s ease-in-out infinite 4.5s;
}

@keyframes float-card {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

.card-icon {
    font-size: 36px;
    margin-bottom: 12px;
}

.card-title {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 4px;
}

.card-desc {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.65);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.hero-scroll {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: rgba(255, 255, 255, 0.5);
    font-size: 12px;
    letter-spacing: 1px;
    z-index: 3;
    animation: fadeIn 1s ease 1s both;
}

.scroll-arrow {
    width: 1px;
    height: 30px;
    background: rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.scroll-arrow::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 50%;
    background: white;
    animation: scroll-down 2s ease-in-out infinite;
}

@keyframes scroll-down {
    0% { transform: translateY(-100%); }
    100% { transform: translateY(200%); }
}

/* ===========================
   通用 Section
   =========================== */
.section {
    padding: 100px 0;
    position: relative;
}

.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 64px;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(27, 152, 224, 0.1);
    color: var(--color-accent-blue);
    font-size: 13px;
    font-weight: 600;
    border-radius: 100px;
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(28px, 4vw, 44px);
    font-weight: 800;
    color: var(--color-primary);
    line-height: 1.2;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.section-desc {
    font-size: 17px;
    color: var(--color-text-light);
    line-height: 1.7;
}

/* ===========================
   关于我们
   =========================== */
.about {
    background: var(--color-bg);
}

.about-grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 60px;
    align-items: start;
    margin-bottom: 80px;
}

.about-main p {
    font-size: 16px;
    color: var(--color-text-light);
    margin-bottom: 20px;
    line-height: 1.8;
}

.about-main p strong {
    color: var(--color-primary);
    font-weight: 700;
}

.about-lead {
    font-size: 17px !important;
    color: var(--color-text) !important;
    font-weight: 500;
}

.about-sub {
    font-size: 17px;
    font-weight: 700;
    letter-spacing: 2px;
    color: var(--color-accent-blue);
    text-transform: uppercase;
    margin: 32px 0 14px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.about-sub::before {
    content: '';
    width: 28px;
    height: 3px;
    background: var(--color-accent-blue);
    display: inline-block;
}

.about-sub:first-child {
    margin-top: 0;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.feature-item {
    padding: 28px 24px;
    background: var(--color-bg-soft);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    transition: all var(--transition);
    display: block;
    text-decoration: none;
    color: inherit;
    position: relative;
    overflow: hidden;
}

.feature-item::after {
    content: '查看详情 →';
    position: absolute;
    bottom: 12px;
    right: 24px;
    font-size: 12px;
    color: var(--color-accent-orange);
    font-weight: 600;
    opacity: 0;
    transition: opacity var(--transition);
}

.feature-item:hover {
    transform: translateY(-4px);
    border-color: var(--color-accent-blue);
    box-shadow: var(--shadow-md);
    background: white;
}

.feature-item:hover::after {
    opacity: 1;
}

.feature-icon {
    font-size: 36px;
    margin-bottom: 16px;
}

.feature-title {
    font-size: 17px;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 8px;
}

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

/* 数据展示 */
.metrics {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
    padding: 48px 32px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    position: relative;
    overflow: hidden;
}

.metrics::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
    background-size: 40px 40px;
    pointer-events: none;
}

.metric {
    text-align: center;
    color: white;
    position: relative;
    z-index: 1;
}

.metric-num {
    font-size: 48px;
    font-weight: 800;
    line-height: 1;
    background: linear-gradient(135deg, #ffffff 0%, #FFD700 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: inline-block;
}

.metric-plus {
    font-size: 32px;
    font-weight: 700;
    color: #FFD700;
    display: inline-block;
    margin-left: 2px;
}

.metric-label {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
    margin-top: 8px;
}

/* ===========================
   业务板块
   =========================== */
.business {
    background: var(--color-bg-soft);
}

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

.business-card {
    position: relative;
    padding: 40px 32px;
    background: white;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: all var(--transition);
    overflow: hidden;
}

.business-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.5s var(--transition);
}

.business-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
    background: var(--color-primary);
    color: white;
}

.business-card:hover::before {
    transform: scaleX(1);
}

.business-card:hover .business-title,
.business-card:hover .business-desc,
.business-card:hover .business-list li {
    color: white;
}

.business-card:hover .business-en {
    color: rgba(255, 255, 255, 0.6);
}

.business-card:hover .business-icon {
    background: rgba(255, 255, 255, 0.1);
    color: #FFD700;
}

.business-card:hover .business-list li {
    border-top-color: rgba(255, 255, 255, 0.1);
}

.business-card:hover .business-list li::before {
    color: #FFD700;
}

.business-card.highlight {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.business-card.highlight .business-title,
.business-card.highlight .business-desc,
.business-card.highlight .business-list li {
    color: white;
}

.business-card.highlight .business-en {
    color: rgba(255, 255, 255, 0.6);
}

.business-card.highlight .business-icon {
    background: rgba(255, 255, 255, 0.1);
    color: #FFD700;
}

.business-num {
    position: absolute;
    top: 24px;
    right: 32px;
    font-size: 60px;
    font-weight: 800;
    color: rgba(11, 37, 69, 0.06);
    line-height: 1;
    font-family: var(--font-en);
}

.business-card.highlight .business-num {
    color: rgba(255, 255, 255, 0.08);
}

.business-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(27, 152, 224, 0.1);
    color: var(--color-accent-blue);
    border-radius: var(--radius-md);
    margin-bottom: 24px;
    transition: all var(--transition);
}

.business-icon svg { width: 36px; height: 36px; }

.business-title {
    font-size: 24px;
    font-weight: 800;
    color: var(--color-primary);
    margin-bottom: 4px;
}

.business-en {
    font-family: var(--font-en);
    font-size: 12px;
    color: var(--color-text-muted);
    letter-spacing: 2px;
    margin-bottom: 16px;
    font-weight: 500;
}

.business-desc {
    font-size: 15px;
    color: var(--color-text-light);
    margin-bottom: 24px;
    line-height: 1.7;
}

.business-list li {
    padding: 8px 0;
    padding-left: 20px;
    font-size: 14px;
    color: var(--color-text-light);
    position: relative;
    border-top: 1px solid rgba(11, 37, 69, 0.06);
}

.business-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-accent-orange);
    font-weight: 700;
}

.business-card.highlight .business-list li {
    border-top-color: rgba(255, 255, 255, 0.1);
}

/* ===========================
   解决方案
   =========================== */
.solutions { background: var(--color-bg); }

.solutions-tabs {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-border);
}

.tabs-nav {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    background: var(--color-bg-soft);
    border-bottom: 1px solid var(--color-border);
}

.tab-btn {
    padding: 24px 16px;
    font-size: 15px;
    font-weight: 600;
    color: var(--color-text-light);
    background: transparent;
    border-right: 1px solid var(--color-border);
    transition: all var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.tab-btn:last-child { border-right: none; }

.tab-icon {
    font-size: 28px;
    transition: transform var(--transition);
}

.tab-btn:hover {
    background: white;
    color: var(--color-primary);
}

.tab-btn.active {
    background: white;
    color: var(--color-primary);
    position: relative;
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-accent);
}

.tab-btn.active .tab-icon {
    transform: scale(1.15);
}

.tabs-content {
    padding: 48px;
    min-height: 400px;
}

.tab-pane { display: none; animation: fadeIn 0.4s ease; }
.tab-pane.active { display: block; }

/* 首页方案快捷卡片（跳转用） */
.solutions-quick-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.quick-card {
    display: block;
    padding: 40px 32px;
    background: white;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    text-align: center;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.quick-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s var(--transition);
}

.quick-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.quick-card:hover::before {
    transform: scaleX(1);
}

.quick-icon {
    font-size: 56px;
    margin-bottom: 20px;
    display: block;
}

.quick-card h3 {
    font-size: 22px;
    font-weight: 800;
    color: var(--color-primary);
    margin-bottom: 10px;
}

.quick-card p {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.6;
    margin-bottom: 20px;
    min-height: 44px;
}

.quick-link {
    display: inline-block;
    padding: 8px 18px;
    background: rgba(27, 152, 224, 0.1);
    color: var(--color-accent-blue);
    font-size: 13px;
    font-weight: 600;
    border-radius: 100px;
    transition: all var(--transition);
}

.quick-card:hover .quick-link {
    background: var(--gradient-accent);
    color: white;
}

/* business-card 可点击改造 */
a.business-card {
    text-decoration: none;
    color: inherit;
    display: block;
}

a.business-card .business-list li {
    transition: transform var(--transition);
}

a.business-card:hover .business-list li:nth-child(1) { transform: translateX(4px); }
a.business-card:hover .business-list li:nth-child(2) { transform: translateX(4px); transition-delay: 0.05s; }
a.business-card:hover .business-list li:nth-child(3) { transform: translateX(4px); transition-delay: 0.1s; }
a.business-card:hover .business-list li:nth-child(4) { transform: translateX(4px); transition-delay: 0.15s; }

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.solution-item {
    padding: 28px 24px;
    background: var(--color-bg-soft);
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    transition: all var(--transition);
}

.solution-item:hover {
    background: white;
    border-color: var(--color-accent-blue);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.solution-item h4 {
    font-size: 17px;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.solution-item h4::before {
    content: '';
    width: 4px;
    height: 18px;
    background: var(--gradient-accent);
    border-radius: 2px;
    flex-shrink: 0;
}

.solution-item p {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.6;
}

/* ===========================
   案例
   =========================== */
.cases { background: var(--color-bg-soft); }

.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
}

.case-card {
    padding: 32px;
    background: white;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.case-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--color-primary);
    opacity: 0;
    transition: opacity var(--transition);
    z-index: 0;
}

.case-card > * { position: relative; z-index: 1; transition: color var(--transition); }

.case-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.case-card:hover::before { opacity: 1; }
.case-card:hover .case-school,
.case-card:hover .case-project { color: white; }
.case-card:hover .case-tags .case-tag {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border-color: rgba(255, 255, 255, 0.3);
}

.case-school {
    font-size: 20px;
    font-weight: 800;
    color: var(--color-primary);
    margin-bottom: 16px;
}

.case-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 16px;
}

.case-tag {
    padding: 4px 12px;
    font-size: 12px;
    font-weight: 500;
    color: var(--color-accent-blue);
    background: rgba(27, 152, 224, 0.1);
    border: 1px solid rgba(27, 152, 224, 0.2);
    border-radius: 100px;
    transition: all var(--transition);
}

.case-project {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.7;
}

/* 案例高亮卡片（保留类用于语义，默认走白底，hover 由 .case-card:hover 统一处理） */
.case-card.highlight-card {
    background: white;
    border-color: var(--color-border);
}

.case-card.highlight-card .case-school {
    color: var(--color-primary);
}

.case-card.highlight-card .case-project {
    color: var(--color-text-light);
}

.case-card.highlight-card .case-tag {
    background: rgba(27, 152, 224, 0.1);
    color: var(--color-accent-blue);
    border-color: rgba(27, 152, 224, 0.2);
}

/* ===========================
   方案子导航标签（新能源/智能造细分）
   =========================== */
.nev-subnav {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 24px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--color-border);
}

.nev-badge {
    display: inline-flex;
    align-items: center;
    padding: 6px 16px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-accent-blue);
    background: rgba(27, 152, 224, 0.08);
    border: 1px solid rgba(27, 152, 224, 0.2);
    border-radius: 100px;
    letter-spacing: 0.5px;
}

.nev-badge:first-child {
    background: var(--color-accent-orange);
    color: white;
    border-color: var(--color-accent-orange);
}

/* ===========================
   联系
   =========================== */
.contact {
    background: white;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 48px;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.contact-item {
    display: flex;
    gap: 16px;
    padding: 24px;
    background: var(--color-bg-soft);
    border-radius: var(--radius-md);
    transition: all var(--transition);
    border: 1px solid transparent;
}

.contact-item:hover {
    background: white;
    border-color: var(--color-accent-blue);
    box-shadow: var(--shadow-md);
    transform: translateX(4px);
}

.contact-icon {
    font-size: 28px;
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(27, 152, 224, 0.1);
    border-radius: var(--radius-sm);
}

.contact-detail h4 {
    font-size: 16px;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 6px;
}

.contact-detail p {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.7;
}

.contact-phone {
    font-size: 20px !important;
    font-weight: 700;
    color: var(--color-accent-orange) !important;
    font-family: var(--font-en);
}

.contact-tip {
    font-size: 12px !important;
    color: var(--color-text-muted) !important;
}

/* 联系表单 */
.contact-form-wrap {
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    padding: 48px;
    color: white;
    position: relative;
    overflow: hidden;
}

.contact-form-wrap::before {
    content: '';
    position: absolute;
    top: -100px;
    right: -100px;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.2) 0%, transparent 70%);
    pointer-events: none;
}

.form-title {
    font-size: 24px;
    font-weight: 800;
    margin-bottom: 8px;
    position: relative;
}

.form-desc {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 32px;
    position: relative;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    position: relative;
}

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

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 8px;
}

.form-group label span {
    color: #FFD700;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-sm);
    color: white;
    font-size: 14px;
    transition: all var(--transition);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: rgba(255, 255, 255, 0.4);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #FFD700;
    background: rgba(255, 255, 255, 0.12);
}

.form-group select {
    appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='2' stroke-linecap='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 18px;
    padding-right: 40px;
}

.form-group select option {
    background: var(--color-primary);
    color: white;
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.form-submit {
    width: 100%;
    justify-content: center;
    margin-top: 8px;
}

.form-note {
    text-align: center;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.5);
    margin-top: 16px;
}

/* 表单提交成功提示条 */
.form-success-bar {
    background: #22c55e;
    color: white;
    padding: 16px 24px;
    border-radius: var(--radius-md);
    font-size: 16px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.4s ease, transform 0.4s ease;
    box-shadow: 0 4px 16px rgba(34, 197, 94, 0.35);
}

.form-success-bar .success-icon {
    font-size: 22px;
}

/* ===========================
   Footer
   =========================== */
.footer {
    background: var(--color-bg-dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 60px 0 24px;
}

.footer-top {
    display: grid;
    grid-template-columns: 1.2fr 2fr;
    gap: 48px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-logo {
    width: 84px;
    height: 70px;
    object-fit: contain;
    opacity: 0.98;
    filter: brightness(0) invert(1);
}

.footer-name {
    font-size: 18px;
    font-weight: 800;
    color: white;
    margin-bottom: 4px;
}

.footer-en {
    font-family: var(--font-en);
    font-size: 11px;
    color: rgba(255, 255, 255, 0.5);
    letter-spacing: 1px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.footer-col h5 {
    font-size: 14px;
    font-weight: 700;
    color: white;
    margin-bottom: 16px;
}

.footer-col a,
.footer-col p {
    display: block;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 10px;
    transition: color var(--transition);
}

.footer-col a:hover { color: #FFD700; }

.footer-phone { color: #FFD700 !important; margin-top: 8px !important; }

.footer-bottom {
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.5);
}

/* ===========================
   回到顶部
   =========================== */
.back-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    color: white;
    border-radius: 50%;
    font-size: 20px;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
    z-index: 50;
}

.back-top.show {
    opacity: 1;
    visibility: visible;
}

.back-top:hover {
    transform: translateY(-4px);
}

/* ===========================
   滚动动画
   =========================== */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===========================
   响应式
   =========================== */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-subtitle { margin-left: auto; margin-right: auto; }
    .hero-stats { margin: 0 auto; }
    .hero-cta { justify-content: center; }
    .hero-visual { height: 360px; max-width: 500px; margin: 0 auto; }

    .about-grid { grid-template-columns: 1fr; }
    .business-grid { grid-template-columns: 1fr; max-width: 500px; margin: 0 auto; }
    .solutions-grid { grid-template-columns: repeat(2, 1fr); }
    .contact-grid { grid-template-columns: 1fr; }

    .footer-top { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .section { padding: 70px 0; }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        gap: 8px;
        box-shadow: var(--shadow-md);
        transform: translateY(-150%);
        transition: transform 0.4s ease;
        align-items: stretch;
    }

    .nav-menu.open { transform: translateY(0); }

    .nav-link {
        text-align: center;
        padding: 12px;
    }

    .nav-link.active::after { display: none; }

    .nav-cta { margin: 8px 0 0; text-align: center; }

    .nav-toggle { display: flex; }

    .hero { padding-top: 110px; min-height: auto; }
    .hero-visual { display: none; }

    .hero-stats {
        gap: 16px;
        flex-wrap: wrap;
    }

    .stat-divider { display: none; }

    .about-features { grid-template-columns: 1fr; }

    .metrics {
        grid-template-columns: repeat(2, 1fr);
        gap: 32px 16px;
    }

    .tabs-nav {
        grid-template-columns: repeat(2, 1fr);
    }

    .tab-btn {
        border-right: 1px solid var(--color-border);
        border-bottom: 1px solid var(--color-border);
    }

    .tab-btn:nth-child(2n) { border-right: none; }
    .tab-btn:nth-last-child(-n+2) { border-bottom: none; }

    .tabs-content { padding: 32px 20px; }
    .solutions-grid { grid-template-columns: 1fr; }

    .contact-form-wrap { padding: 32px 24px; }

    .form-row { grid-template-columns: 1fr; gap: 0; }

    .footer-links {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .footer-brand { justify-content: center; text-align: center; flex-direction: column; }

    .back-top {
        bottom: 20px;
        right: 20px;
        width: 42px;
        height: 42px;
    }
}

@media (max-width: 480px) {
    .container { padding: 0 16px; }
    .nav-container { padding: 0 16px; }

    .hero-badge { font-size: 12px; padding: 6px 12px; }

    .metric-num { font-size: 36px; }
    .metric-plus { font-size: 24px; }

    .cases-grid { grid-template-columns: 1fr; }
}