/* ===================================
   必果ERP Landing Page Styles
   SEO Optimized & Mobile Responsive
   =================================== */

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

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --secondary: #10b981;
    --accent: #f59e0b;
    --dark: #1e293b;
    --gray-900: #0f172a;
    --gray-800: #1e293b;
    --gray-700: #334155;
    --gray-600: #475569;
    --gray-500: #64748b;
    --gray-400: #94a3b8;
    --gray-300: #cbd5e1;
    --gray-200: #e2e8f0;
    --gray-100: #f1f5f9;
    --gray-50: #f8fafc;
    --white: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
    --radius: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--gray-700);
    background: var(--white);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

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

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

/* ===================================
   Header
   =================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.header.scrolled {
    border-bottom-color: var(--gray-200);
    box-shadow: var(--shadow-sm);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 40px;
    width: auto;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.nav {
    display: flex;
    gap: 32px;
}

.nav a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--gray-600);
    position: relative;
}

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

.nav a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

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

.header-btn {
    display: flex;
    gap: 12px;
}

.btn-login {
    padding: 8px 20px;
    border-radius: var(--radius);
    color: var(--gray-700);
    font-weight: 500;
}

.btn-login:hover {
    color: var(--primary);
}

.btn-cta {
    padding: 8px 20px;
    border-radius: var(--radius);
    background: var(--primary);
    color: var(--white);
    font-weight: 500;
}

.btn-cta:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--gray-700);
    transition: var(--transition);
}

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

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

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

.mobile-menu {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow-md);
    z-index: 999;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu nav {
    display: flex;
    flex-direction: column;
    padding: 20px;
}

.mobile-menu nav a {
    padding: 12px 0;
    border-bottom: 1px solid var(--gray-100);
    font-weight: 500;
}

.mobile-menu nav a:last-child {
    border-bottom: none;
}

.mobile-login {
    color: var(--primary) !important;
    margin-top: 10px;
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(135deg, var(--gray-50) 0%, var(--primary-light) 100%);
    min-height: 90vh;
    display: flex;
    align-items: center;
}

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

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.2;
    color: var(--gray-900);
    margin-bottom: 20px;
}

.hero-title .highlight {
    color: var(--primary);
    position: relative;
}

.hero-title .highlight::after {
    content: '';
    position: absolute;
    bottom: 5px;
    left: 0;
    width: 100%;
    height: 12px;
    background: var(--primary-light);
    z-index: -1;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--gray-600);
    margin-bottom: 30px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-bottom: 40px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--gray-500);
}

.hero-actions {
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--white);
    color: var(--gray-700);
    border: 1px solid var(--gray-300);
}

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

.btn-large {
    padding: 16px 40px;
    font-size: 1.1rem;
}

/* Dashboard Preview */
.hero-image {
    position: relative;
}

.dashboard-preview {
    background: var(--white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    transform: perspective(1000px) rotateY(-5deg) rotateX(2deg);
    transition: var(--transition);
}

.dashboard-preview:hover {
    transform: perspective(1000px) rotateY(0deg) rotateX(0deg);
}

.preview-header {
    background: var(--gray-100);
    padding: 12px 16px;
    display: flex;
    gap: 8px;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #f59e0b; }
.dot.green { background: #10b981; }

.preview-content {
    display: grid;
    grid-template-columns: 160px 1fr;
    min-height: 300px;
}

.preview-sidebar {
    background: var(--gray-50);
    padding: 20px 16px;
    border-right: 1px solid var(--gray-200);
}

.preview-sidebar .menu-item {
    padding: 10px 12px;
    border-radius: var(--radius);
    font-size: 0.85rem;
    color: var(--gray-600);
    margin-bottom: 4px;
}

.preview-sidebar .menu-item.active {
    background: var(--primary-light);
    color: var(--primary);
    font-weight: 600;
}

.preview-main {
    padding: 20px;
}

.preview-chart {
    display: flex;
    align-items: flex-end;
    gap: 12px;
    height: 150px;
    margin-bottom: 20px;
}

.preview-chart .bar {
    flex: 1;
    background: linear-gradient(to top, var(--primary), var(--primary-light));
    border-radius: 4px 4px 0 0;
    animation: barGrow 1s ease-out;
}

@keyframes barGrow {
    from { height: 0; }
}

.preview-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.mini-card {
    background: var(--gray-50);
    padding: 16px;
    border-radius: var(--radius);
    display: flex;
    flex-direction: column;
}

.card-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
}

.card-label {
    font-size: 0.8rem;
    color: var(--gray-500);
}

/* ===================================
   Section Common
   =================================== */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--gray-500);
}

/* ===================================
   Pain Points Section
   =================================== */
.pain-points {
    padding: 100px 0;
    background: var(--white);
}

.pain-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.pain-card {
    background: var(--gray-50);
    padding: 40px 30px;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--gray-100);
}

.pain-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: #fecaca;
    background: linear-gradient(135deg, #fff5f5 0%, var(--white) 100%);
}

.pain-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    background: #fee2e2;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.pain-icon svg {
    width: 32px;
    height: 32px;
    color: #ef4444;
}

.pain-card h3 {
    font-size: 1.2rem;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.pain-card p {
    font-size: 0.95rem;
    color: var(--gray-500);
    line-height: 1.6;
}

/* ===================================
   Features Section
   =================================== */
.features {
    padding: 100px 0;
    background: var(--gray-50);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-card {
    background: var(--white);
    padding: 40px 30px;
    border-radius: var(--radius-lg);
    transition: var(--transition);
    border: 1px solid var(--gray-100);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: var(--white);
}

.bg-blue { background: linear-gradient(135deg, #3b82f6, #2563eb); }
.bg-green { background: linear-gradient(135deg, #10b981, #059669); }
.bg-orange { background: linear-gradient(135deg, #f59e0b, #d97706); }
.bg-purple { background: linear-gradient(135deg, #8b5cf6, #7c3aed); }
.bg-red { background: linear-gradient(135deg, #ef4444, #dc2626); }
.bg-cyan { background: linear-gradient(135deg, #06b6d4, #0891b2); }

.feature-card h3 {
    font-size: 1.25rem;
    color: var(--gray-900);
    margin-bottom: 16px;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    padding: 8px 0;
    font-size: 0.9rem;
    color: var(--gray-600);
    position: relative;
    padding-left: 20px;
}

.feature-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

/* ===================================
   Advantages Section
   =================================== */
.advantages {
    padding: 100px 0;
    background: var(--white);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.advantage-item {
    text-align: center;
    padding: 30px;
}

.advantage-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--primary-light);
    margin-bottom: 16px;
    line-height: 1;
}

.advantage-item h3 {
    font-size: 1.25rem;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.advantage-item p {
    font-size: 0.95rem;
    color: var(--gray-500);
    line-height: 1.6;
}

/* ===================================
   Cases Section
   =================================== */
.cases {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--gray-900) 0%, var(--gray-800) 100%);
}

.cases .section-title {
    color: var(--white);
}

.cases .section-subtitle {
    color: var(--gray-400);
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.case-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: 30px;
    transition: var(--transition);
}

.case-card:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-5px);
}

.case-content {
    margin-bottom: 24px;
}

.case-content p {
    color: var(--gray-300);
    font-size: 1rem;
    line-height: 1.8;
    font-style: italic;
}

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

.author-avatar {
    width: 48px;
    height: 48px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-weight: 700;
    font-size: 1.2rem;
}

.author-info h4 {
    color: var(--white);
    font-size: 1rem;
    margin-bottom: 4px;
}

.author-info p {
    color: var(--gray-400);
    font-size: 0.85rem;
}

/* ===================================
   CTA Section
   =================================== */
.cta {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    text-align: center;
}

.cta-content h2 {
    font-size: 2.5rem;
    color: var(--white);
    margin-bottom: 16px;
}

.cta-content > p {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 40px;
}

.cta-actions {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 40px;
}

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

.cta .btn-primary:hover {
    background: var(--gray-100);
}

.cta .btn-secondary {
    background: transparent;
    color: var(--white);
    border-color: rgba(255, 255, 255, 0.5);
}

.cta .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--white);
}

.cta .btn svg {
    width: 20px;
    height: 20px;
    margin-right: 8px;
}

.cta-info {
    display: flex;
    justify-content: center;
    gap: 40px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: rgba(255, 255, 255, 0.9);
}

.info-item svg {
    width: 20px;
    height: 20px;
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: var(--gray-900);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-brand img {
    height: 40px;
    margin-bottom: 16px;
    filter: brightness(0) invert(1);
}

.footer-brand p {
    color: var(--gray-400);
    font-size: 0.95rem;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.link-group h4 {
    color: var(--white);
    font-size: 1rem;
    margin-bottom: 20px;
}

.link-group a {
    display: block;
    color: var(--gray-400);
    font-size: 0.9rem;
    padding: 6px 0;
}

.link-group a:hover {
    color: var(--white);
}

.footer-bottom {
    border-top: 1px solid var(--gray-800);
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    color: var(--gray-500);
    font-size: 0.85rem;
}

/* ===================================
   Animations
   =================================== */
.feature-card,
.pain-card,
.advantage-item,
.case-card {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature-card.animated,
.pain-card.animated,
.advantage-item.animated,
.case-card.animated {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger animation */
.feature-card:nth-child(2),
.pain-card:nth-child(2),
.advantage-item:nth-child(2),
.case-card:nth-child(2) {
    transition-delay: 0.1s;
}

.feature-card:nth-child(3),
.pain-card:nth-child(3),
.advantage-item:nth-child(3),
.case-card:nth-child(3) {
    transition-delay: 0.2s;
}

.feature-card:nth-child(4),
.pain-card:nth-child(4),
.advantage-item:nth-child(4) {
    transition-delay: 0.3s;
}

.feature-card:nth-child(5),
.pain-card:nth-child(5),
.advantage-item:nth-child(5) {
    transition-delay: 0.4s;
}

.feature-card:nth-child(6),
.pain-card:nth-child(6),
.advantage-item:nth-child(6) {
    transition-delay: 0.5s;
}

/* ===================================
   Responsive
   =================================== */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
    }
    
    .hero-image {
        display: none;
    }
    
    .pain-grid,
    .features-grid,
    .advantages-grid,
    .cases-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav,
    .header-btn {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero {
        padding: 120px 0 60px;
        min-height: auto;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-stats {
        flex-wrap: wrap;
        gap: 20px;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .pain-grid,
    .features-grid,
    .advantages-grid,
    .cases-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .cta-content h2 {
        font-size: 1.75rem;
    }
    
    .cta-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .cta-info {
        flex-direction: column;
        gap: 16px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.75rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
    }
}