/* ============================================
   TanCloud Global - Brand Website Styles
   ============================================ */

/* --- CSS Variables --- */
:root {
    --primary: #1a365d;
    --primary-light: #2b6cb0;
    --primary-dark: #0f2440;
    --accent: #f6ad55;
    --accent-light: #fbd38d;
    --gradient-start: #2b6cb0;
    --gradient-end: #4299e1;
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --bg-white: #ffffff;
    --bg-light: #f7fafc;
    --bg-section: #edf2f7;
    --border: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.12);
    --shadow-xl: 0 20px 60px rgba(0,0,0,0.15);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-cn: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    --font-en: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-cn);
    color: var(--text-primary);
    background: var(--bg-white);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

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

ul { list-style: none; }

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

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

/* --- Gradient Text --- */
.gradient-text {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 600;
    font-family: var(--font-cn);
    cursor: pointer;
    border: none;
    transition: var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    box-shadow: 0 4px 15px rgba(43, 108, 176, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(43, 108, 176, 0.5);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}

.btn-lg {
    padding: 16px 36px;
    font-size: 16px;
}

.btn-block {
    width: 100%;
    justify-content: center;
}

/* ============================================
   Navigation
   ============================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow-sm);
    padding: 10px 0;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    z-index: 1001;
}

.logo-icon {
    width: 40px;
    height: 40px;
    /* background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)); */
    color: white;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: 14px;
    font-family: var(--font-en);
    letter-spacing: -0.5px;
}
.logo-icon-img{
    border-radius: var(--radius-sm);
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: white;
    font-family: var(--font-en);
    transition: var(--transition);
}

.logo-text small {
    font-weight: 400;
    font-size: 13px;
    opacity: 0.8;
}

.navbar.scrolled .logo-text {
    color: var(--primary);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-menu a {
    font-size: 14px;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.85);
    position: relative;
    padding: 4px 0;
}

.navbar.scrolled .nav-menu a {
    color: var(--text-secondary);
}

.nav-menu a:hover {
    color: white;
}

.navbar.scrolled .nav-menu a:hover {
    color: var(--primary);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: var(--transition);
}

.nav-menu a:hover::after {
    width: 100%;
}

.nav-cta {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)) !important;
    color: white !important;
    padding: 8px 20px !important;
    border-radius: var(--radius-sm) !important;
}

.nav-cta::after { display: none !important; }

.nav-cta:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(43, 108, 176, 0.4);
}

/* Language Toggle */
.lang-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: white;
    font-size: 13px;
    font-weight: 600;
    font-family: var(--font-en);
    padding: 6px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: 0.5px;
    white-space: nowrap;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.lang-toggle:hover {
    background: rgba(255, 255, 255, 0.25);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-1px);
}

/* Language toggle in scrolled state */
.navbar.scrolled .lang-toggle {
    background: rgba(26, 54, 93, 0.08);
    border-color: rgba(26, 54, 93, 0.2);
    color: var(--primary);
}

.navbar.scrolled .lang-toggle:hover {
    background: rgba(26, 54, 93, 0.15);
    border-color: rgba(26, 54, 93, 0.3);
}

/* Language toggle in mobile menu-open state */
.navbar.menu-open .lang-toggle {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    color: white;
}

/* Mobile Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 1001;
}

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

.navbar.scrolled .nav-toggle span {
    background: var(--primary);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

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

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: url('../assets/images/hero-bg.jpg') center/cover no-repeat;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        135deg,
        rgba(26, 54, 93, 0.92) 0%,
        rgba(15, 36, 64, 0.85) 50%,
        rgba(43, 108, 176, 0.75) 100%
    );
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 120px 24px 80px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 32px;
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: #48bb78;
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-size: clamp(36px, 6vw, 72px);
    font-weight: 900;
    color: white;
    line-height: 1.2;
    margin-bottom: 24px;
    letter-spacing: -1px;
}

.hero-desc {
    font-size: clamp(15px, 2vw, 18px);
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.8;
    margin-bottom: 48px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    max-width: 800px;
    margin: 0 auto 48px;
    padding: 32px;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-lg);
}

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

.stat-number {
    font-size: clamp(28px, 4vw, 42px);
    font-weight: 800;
    color: white;
    font-family: var(--font-en);
}

.stat-suffix {
    font-size: clamp(16px, 2vw, 22px);
    font-weight: 600;
    color: var(--accent);
}

.stat-label {
    display: block;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 4px;
}

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

.hero-actions .btn-outline {
    border-color: rgba(255, 255, 255, 0.5);
    color: white;
}

.hero-actions .btn-outline:hover {
    background: white;
    color: var(--primary);
    border-color: white;
}

.hero-scroll {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
    font-size: 12px;
}

.scroll-arrow {
    width: 20px;
    height: 20px;
    border-right: 2px solid rgba(255, 255, 255, 0.6);
    border-bottom: 2px solid rgba(255, 255, 255, 0.6);
    transform: rotate(45deg);
    margin: 8px auto 0;
    animation: scrollDown 2s infinite;
}

@keyframes scrollDown {
    0% { opacity: 1; transform: rotate(45deg) translate(0, 0); }
    100% { opacity: 0; transform: rotate(45deg) translate(8px, 8px); }
}

/* ============================================
   Section Common
   ============================================ */
.section {
    padding: 100px 0;
}

.section:nth-child(even) {
    background: var(--bg-light);
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-tag {
    display: inline-block;
    font-size: 13px;
    font-weight: 700;
    color: var(--primary-light);
    letter-spacing: 2px;
    margin-bottom: 12px;
    font-family: var(--font-en);
}

.section-title {
    font-size: clamp(28px, 4vw, 42px);
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.section-subtitle {
    font-size: 17px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   About Section
   ============================================ */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.about-text p {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 40px;
}

.about-features {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.feature-card {
    display: flex;
    gap: 16px;
    padding: 20px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.feature-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--gradient-start);
    transform: translateX(4px);
}

.feature-icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.1), rgba(66, 153, 225, 0.1));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-light);
}

.feature-card h4 {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* Timeline */
.timeline-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 32px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--border);
}

.timeline {
    position: relative;
    padding-left: 28px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 6px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border);
}

.timeline-item {
    position: relative;
    padding-bottom: 28px;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-dot {
    position: absolute;
    left: -25px;
    top: 4px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--bg-white);
    border: 2px solid var(--border);
    transition: var(--transition);
}

.timeline-item.active .timeline-dot {
    background: var(--gradient-start);
    border-color: var(--gradient-start);
    box-shadow: 0 0 0 4px rgba(43, 108, 176, 0.2);
}

.timeline-year {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    color: var(--primary-light);
    background: rgba(43, 108, 176, 0.1);
    padding: 2px 10px;
    border-radius: 4px;
    margin-bottom: 6px;
    font-family: var(--font-en);
}

.timeline-content h4 {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.timeline-content p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* ============================================
   Services Section
   ============================================ */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.service-card {
    position: relative;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    border: 1px solid var(--border);
    transition: var(--transition);
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
    transform: scaleX(0);
    transition: var(--transition);
}

.service-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: transparent;
}

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

.service-number {
    position: absolute;
    top: 16px;
    right: 20px;
    font-size: 48px;
    font-weight: 900;
    color: rgba(43, 108, 176, 0.06);
    font-family: var(--font-en);
    line-height: 1;
}

.service-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.1), rgba(66, 153, 225, 0.05));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-light);
    margin-bottom: 20px;
}

.service-card h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 12px;
}

.service-card > p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 20px;
}

.service-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.service-list li {
    font-size: 13px;
    color: var(--text-secondary);
    padding-left: 20px;
    position: relative;
}

.service-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--gradient-start);
}

/* ============================================
   Team Section
   ============================================ */
.team-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 60px;
}

.highlight-card {
    text-align: center;
    padding: 32px 20px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.highlight-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.highlight-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.1), rgba(66, 153, 225, 0.05));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-light);
    margin: 0 auto 16px;
}

.highlight-card h3 {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
}

.highlight-card p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* Data Showcase */
.data-showcase {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.data-card {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: var(--radius-lg);
    padding: 32px;
    color: white;
    position: relative;
    overflow: hidden;
}

.data-card::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(255,255,255,0.05) 0%, transparent 70%);
}

.data-card:nth-child(2) {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
}

.data-card:nth-child(3) {
    background: linear-gradient(135deg, #2d3748, #1a202c);
}

.data-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.data-badge {
    background: rgba(255, 255, 255, 0.2);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 600;
}

.data-tag {
    font-size: 12px;
    color: rgba(255, 255, 255, 0.7);
}

.big-number {
    font-size: clamp(28px, 3.5vw, 40px);
    font-weight: 800;
    font-family: var(--font-en);
    margin-bottom: 12px;
    position: relative;
    z-index: 1;
}

.big-number .unit {
    font-size: 16px;
    font-weight: 500;
    opacity: 0.8;
}

.data-card-body p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.6;
    position: relative;
    z-index: 1;
}

/* ============================================
   Capabilities Section
   ============================================ */
.capabilities-tabs {
    max-width: 1000px;
    margin: 0 auto;
}

.tab-buttons {
    display: flex;
    gap: 8px;
    margin-bottom: 40px;
    justify-content: center;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 12px 28px;
    border: 2px solid var(--border);
    background: var(--bg-white);
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font-cn);
}

.tab-btn:hover {
    border-color: var(--primary-light);
    color: var(--primary);
}

.tab-btn.active {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    border-color: transparent;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.capability-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.cap-card {
    padding: 28px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.cap-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.cap-card.highlight {
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.05), rgba(66, 153, 225, 0.02));
    border-color: rgba(43, 108, 176, 0.2);
}

.cap-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.1), rgba(66, 153, 225, 0.05));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-light);
    margin-bottom: 16px;
}

.cap-metric {
    display: inline-block;
    font-size: 14px;
    font-weight: 700;
    color: var(--primary-light);
    background: rgba(43, 108, 176, 0.1);
    padding: 4px 12px;
    border-radius: 4px;
    margin-bottom: 12px;
    font-family: var(--font-en);
}

.cap-card h4 {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
}

.cap-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
}

/* ============================================
   Cases Section
   ============================================ */
.case-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
    margin-bottom: 32px;
    transition: var(--transition);
    position: relative;
}

.case-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
    opacity: 0;
    transition: var(--transition);
}

.case-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.case-card:hover::before {
    opacity: 1;
}

.case-header {
    padding: 36px 36px 0;
}

.case-badge {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    color: var(--primary-light);
    background: rgba(43, 108, 176, 0.1);
    padding: 5px 14px;
    border-radius: 20px;
    margin-bottom: 14px;
    letter-spacing: 0.5px;
}

.case-badge.success {
    background: rgba(72, 187, 120, 0.1);
    color: #276749;
}

.case-header h3 {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
    line-height: 1.3;
}

.case-header p {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.6;
}

.case-body {
    padding: 32px 36px 36px;
    display: grid;
    grid-template-columns: 1fr 1fr 1.2fr;
    gap: 32px;
}

.case-body.case-body-full {
    grid-template-columns: 1fr !important;
}

.case-body.case-body-full .case-achievements {
    grid-template-columns: repeat(4, 1fr);
    width: 100%;
}

/* Case Sub-sections */
.case-problem,
.case-solution,
.case-results {
    padding: 10px;
    background: var(--bg-light);
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    transition: var(--transition);
}

.case-problem:hover,
.case-solution:hover,
.case-results:hover {
    border-color: var(--border);
    box-shadow: var(--shadow-sm);
}

.case-problem h4,
.case-solution h4,
.case-results h4 {
    font-size: 13px;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 18px;
    font-family: var(--font-en);
    display: flex;
    align-items: center;
    gap: 8px;
}

.case-problem h4::before {
    content: '';
    width: 3px;
    height: 14px;
    background: #e53e3e;
    border-radius: 2px;
}

.case-solution h4::before {
    content: '';
    width: 3px;
    height: 14px;
    background: linear-gradient(180deg, var(--gradient-start), var(--gradient-end));
    border-radius: 2px;
}

.case-results h4::before {
    content: '';
    width: 3px;
    height: 14px;
    background: #276749;
    border-radius: 2px;
}

.problem-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.problem-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--text-secondary);
    padding: 10px 14px;
    background: var(--bg-white);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.problem-item:hover {
    border-color: rgba(229, 62, 62, 0.3);
    box-shadow: 0 2px 8px rgba(229, 62, 62, 0.08);
}

.problem-icon {
    width: 24px;
    height: 24px;
    background: rgba(229, 62, 62, 0.1);
    color: #e53e3e;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 700;
    flex-shrink: 0;
}

.solution-steps {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.step {
    display: flex;
    align-items: center;
    gap: 14px;
    font-size: 14px;
    color: var(--text-secondary);
    padding: 10px 14px;
    background: var(--bg-white);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.step:hover {
    border-color: rgba(43, 108, 176, 0.3);
    box-shadow: 0 2px 8px rgba(43, 108, 176, 0.08);
}

.step-num {
    width: 30px;
    height: 30px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
    flex-shrink: 0;
    box-shadow: 0 2px 8px rgba(43, 108, 176, 0.3);
}

.results-table {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.result-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 16px;
    background: var(--bg-white);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.result-row:hover {
    box-shadow: var(--shadow-sm);
}

.result-label {
    font-size: 13px;
    color: var(--text-muted);
    min-width: 70px;
    font-weight: 500;
}

.result-before {
    font-size: 14px;
    font-weight: 600;
    color: #e53e3e;
    font-family: var(--font-en);
    background: rgba(229, 62, 62, 0.08);
    padding: 2px 10px;
    border-radius: 4px;
}

.result-arrow {
    color: var(--text-muted);
    font-family: var(--font-en);
    font-size: 13px;
}

.result-after {
    font-size: 14px;
    font-weight: 700;
    color: #276749;
    font-family: var(--font-en);
    background: rgba(72, 187, 120, 0.08);
    padding: 2px 10px;
    border-radius: 4px;
}

/* Achievements */
.case-achievements {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    padding: 24px 0;
}

.achievement {
    text-align: center;
    padding: 28px 20px;
    background: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.achievement::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
    opacity: 0;
    transition: var(--transition);
}

.achievement:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-light);
}

.achievement:hover::before {
    opacity: 1;
}

.achievement-icon {
    font-size: 36px;
    margin-bottom: 16px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.1) 0%, rgba(66, 153, 225, 0.1) 100%);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.achievement:hover .achievement-icon {
    transform: scale(1.1);
    background: linear-gradient(135deg, rgba(43, 108, 176, 0.15) 0%, rgba(66, 153, 225, 0.15) 100%);
}

.achievement-value {
    font-size: 22px;
    font-weight: 800;
    color: var(--primary);
    font-family: var(--font-en);
    margin-bottom: 6px;
    letter-spacing: -0.5px;
}

.achievement-label {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Trust Section */
.trust-section {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    margin-top: 48px;
}

.trust-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    background: var(--bg-light);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--text-secondary);
}

.trust-item svg {
    flex-shrink: 0;
    color: #48bb78;
}

/* ============================================
   Pricing Section
   ============================================ */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    border: 2px solid var(--border);
    transition: var(--transition);
    position: relative;
    text-align: center;
}

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

.pricing-card.featured {
    border-color: var(--gradient-start);
    box-shadow: var(--shadow-lg);
    transform: scale(1.05);
}

.pricing-card.featured:hover {
    transform: scale(1.05) translateY(-4px);
}

.pricing-popular {
    position: absolute;
    top: -14px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    padding: 4px 20px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 700;
}

.pricing-header h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.pricing-header p {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.pricing-price {
    margin-bottom: 28px;
}

.price-amount {
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
    font-family: var(--font-en);
}

.price-period {
    font-size: 15px;
    color: var(--text-muted);
}

.pricing-features {
    text-align: left;
    margin-bottom: 28px;
}

.pricing-features li {
    padding: 8px 0;
    font-size: 14px;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.pricing-features li::before {
    content: '✓';
    color: #48bb78;
    font-weight: 700;
    flex-shrink: 0;
}

.pricing-tag {
    font-size: 12px;
    color: var(--text-muted);
    padding: 8px 16px;
    background: var(--bg-light);
    border-radius: var(--radius-sm);
    margin-bottom: 20px;
}

/* ============================================
   Contact Section
   ============================================ */
.contact {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.contact-wrapper.contact-wrapper-center {
    grid-template-columns: 1fr;
    justify-items: center;
    max-width: 480px;
    margin: 0 auto;
}

.contact-wrapper.contact-wrapper-center .contact-qr-wrapper {
    width: 100%;
}

.contact-qr-large h2 {
    font-size: clamp(26px, 3.5vw, 32px);
    font-weight: 800;
    line-height: 1.3;
    color: var(--primary);
    margin-bottom: 8px;
    text-align: center;
}

.contact-qr-large h2 .gradient-text {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Features inline */
.contact-features-inline {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px 24px;
    margin-top: 8px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

.contact-feature-inline {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--text-secondary);
}

.contact-feature-inline svg {
    color: var(--primary-light);
    flex-shrink: 0;
}

.contact-qr-wrapper {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: 48px 40px;
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    justify-content: center;
}

.contact-qr-large {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 20px;
}

.qr-image-large {
    width: 240px;
    height: auto;
    border-radius: var(--radius-lg);
    border: 4px solid var(--border);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
    transition: var(--transition);
    background: white;
}

.qr-image-large:hover {
    transform: scale(1.03);
    border-color: var(--primary-light);
    box-shadow: 0 12px 40px rgba(43, 108, 176, 0.2);
}

.qr-label-large {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 1px;
}

.qr-desc {
    font-size: 14px;
    color: var(--text-muted);
    max-width: 280px;
    line-height: 1.5;
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: #0f172a;
    color: rgba(255, 255, 255, 0.7);
    padding: 60px 0 0;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand p {
    font-size: 14px;
    margin-top: 16px;
    line-height: 1.7;
}

.footer .logo-text {
    color: white;
}

.footer-links h4,
.footer-contact h4 {
    font-size: 15px;
    font-weight: 700;
    color: white;
    margin-bottom: 16px;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-links a {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-links a:hover {
    color: var(--accent);
}

.footer-contact p {
    font-size: 14px;
    line-height: 1.7;
}

.footer-bottom {
    padding: 20px 0;
    text-align: center;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.4);
}

/* ============================================
   Back to Top
   ============================================ */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* ============================================
   Animations
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .case-body {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .pricing-card.featured {
        transform: scale(1);
    }

    .pricing-card.featured:hover {
        transform: translateY(-4px);
    }
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(15, 36, 64, 0.97);
        backdrop-filter: blur(24px);
        -webkit-backdrop-filter: blur(24px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 8px;
        opacity: 0;
        visibility: hidden;
        transition: opacity 0.35s ease, visibility 0.35s ease;
        z-index: 10000;
    }

    .nav-menu.active {
        opacity: 1;
        visibility: visible;
    }

    .nav-menu li {
        width: 100%;
        text-align: center;
    }

    .nav-menu a {
        display: block;
        font-size: 20px;
        font-weight: 600;
        color: rgba(255, 255, 255, 0.9) !important;
        padding: 14px 24px;
        border-radius: var(--radius-sm);
        transition: var(--transition);
        letter-spacing: 1px;
    }

    .nav-menu a:hover {
        background: rgba(255, 255, 255, 0.08);
        color: white !important;
    }

    .nav-menu .nav-cta {
        display: inline-block !important;
        margin-top: 16px;
        background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)) !important;
        color: white !important;
        padding: 14px 48px !important;
        border-radius: var(--radius-sm) !important;
        font-size: 17px !important;
        box-shadow: 0 4px 20px rgba(43, 108, 176, 0.5);
        letter-spacing: 2px;
    }

    .nav-menu .nav-cta:hover {
        transform: translateY(-2px);
        box-shadow: 0 6px 24px rgba(43, 108, 176, 0.6) !important;
        background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)) !important;
    }

    .nav-toggle {
        width: 40px;
        height: 40px;
        align-items: center;
        justify-content: center;
    }

    .nav-toggle span {
        width: 26px;
        height: 2.5px;
    }

    /* 菜单打开时，强制 logo 和按钮为白色（覆盖 scrolled 状态） */
    .nav-toggle.active span {
        background: white !important;
    }

    .navbar.menu-open {
        background: transparent !important;
        box-shadow: none !important;
        backdrop-filter: none !important;
        z-index: 10001;
    }

    .navbar.menu-open .logo-text {
        color: white !important;
    }

    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
        padding: 24px;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .hero-actions .btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }

    .section {
        padding: 70px 0;
    }

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

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

    .data-showcase {
        grid-template-columns: 1fr;
    }

    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
    }

    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .contact-wrapper.contact-wrapper-center {
        max-width: 100%;
        padding: 0 16px;
    }

    .contact-qr-wrapper {
        padding: 32px 24px;
    }

    .qr-image-large {
        width: 200px;
    }

    .qr-label-large {
        font-size: 16px;
    }

    .contact-features-inline {
        gap: 12px 16px;
    }

    .contact-feature-inline {
        font-size: 13px;
    }

    .case-body.case-body-full .case-achievements,
    .case-achievements {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
        padding: 16px 0;
    }

    .achievement {
        padding: 20px 12px;
    }

    .achievement-icon {
        width: 52px;
        height: 52px;
        font-size: 28px;
        margin-bottom: 12px;
    }

    .achievement-value {
        font-size: 18px;
    }

    .achievement-label {
        font-size: 12px;
    }

    .trust-section {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }

    .tab-buttons {
        gap: 8px;
    }

    .tab-btn {
        padding: 10px 20px;
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 32px;
    }

    .hero-stats {
        grid-template-columns: 1fr 1fr;
    }

    .team-highlights {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 24px;
        text-align: center;
        padding-bottom: 24px;
    }

    .footer-brand {
        display: flex;
        flex-direction: column;
        align-items: center;
        order: 1;
        padding-bottom: 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .footer-links:first-of-type {
        order: 2;
    }

    .footer-links:last-of-type {
        order: 4;
    }

    .footer-contact {
        order: 3;
        background: rgba(255, 255, 255, 0.03);
        border-radius: 12px;
        padding: 16px;
        border: 1px solid rgba(255, 255, 255, 0.06);
    }

    .footer-brand .logo {
        justify-content: center;
    }

    .footer-brand p {
        font-size: 13px;
        margin-top: 12px;
        line-height: 1.6;
        color: rgba(255, 255, 255, 0.6);
    }

    .footer-links h4,
    .footer-contact h4 {
        font-size: 13px;
        margin-bottom: 10px;
        color: rgba(255, 255, 255, 0.9);
        letter-spacing: 0.5px;
    }

    .footer-links ul {
        gap: 6px;
        align-items: center;
    }

    .footer-links a {
        font-size: 13px;
        padding: 6px 12px;
        border-radius: 6px;
        transition: var(--transition);
    }

    .footer-links a:hover {
        background: rgba(255, 255, 255, 0.08);
        color: white;
    }

    .footer-contact p {
        font-size: 13px;
        line-height: 1.7;
        color: rgba(255, 255, 255, 0.65);
    }

    .footer-bottom {
        padding: 14px 0;
        font-size: 11px;
    }

    .contact-qr-wrapper {
        padding: 32px 24px;
    }

    .qr-image-large {
        width: 200px;
    }

    .qr-label-large {
        font-size: 16px;
    }
}