/* ============================================
   为至科技 - 企业官网样式
   设计参考：UiPath, Laiye 等行业标杆
   ============================================ */

/* --- CSS Variables --- */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #111118;
    --bg-card: #1a1a24;
    --bg-card-hover: #22222e;
    --bg-elevated: #16161f;

    --text-primary: #f0f0f5;
    --text-secondary: #a0a0b8;
    --text-muted: #6b6b80;

    --accent: #4f6ef6;
    --accent-light: #7b92ff;
    --accent-glow: rgba(79, 110, 246, 0.3);

    --gradient-1: linear-gradient(135deg, #4f6ef6 0%, #7c4dff 50%, #00bcd4 100%);
    --gradient-2: linear-gradient(135deg, #7c4dff 0%, #4f6ef6 100%);
    --gradient-dark: linear-gradient(180deg, #0a0a0f 0%, #111118 50%, #0a0a0f 100%);

    --border: rgba(255, 255, 255, 0.06);
    --border-light: rgba(255, 255, 255, 0.1);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 16px 64px rgba(0, 0, 0, 0.5);

    --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', monospace;

    --max-width: 1200px;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

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

a { color: inherit; text-decoration: none; }

/* --- Navigation --- */
.navbar {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    padding: 12px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px; height: 36px;
    background: var(--gradient-1);
    border-radius: var(--radius-sm);
    color: #fff;
    font-size: 1.1rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 8px;
}

.nav-link {
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.06);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-btn span {
    display: block;
    width: 24px; height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 60px;
    overflow: hidden;
}

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

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

.hero-glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.15;
}

.hero-glow-1 {
    top: -20%;
    left: 30%;
    width: 600px; height: 600px;
    background: var(--accent);
}

.hero-glow-2 {
    bottom: -10%;
    right: 20%;
    width: 400px; height: 400px;
    background: #7c4dff;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: rgba(79, 110, 246, 0.1);
    border: 1px solid rgba(79, 110, 246, 0.3);
    border-radius: 50px;
    font-size: 0.85rem;
    color: var(--accent-light);
    margin-bottom: 32px;
}

.pulse-dot {
    width: 8px; height: 8px;
    background: var(--accent-light);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.3); }
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 900;
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin-bottom: 24px;
}

.gradient-text {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 40px;
    max-width: 680px;
    margin-left: auto; margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 64px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background: var(--gradient-2);
    color: #fff;
    box-shadow: 0 4px 24px var(--accent-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 40px var(--accent-glow);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.06);
    color: var(--text-primary);
    border: 1px solid var(--border-light);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

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

/* Hero Stats */
.hero-stats {
    display: flex;
    justify-content: center;
    gap: 48px;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 900;
    letter-spacing: -0.02em;
    display: inline;
}

.stat-plus {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 4px;
}

.hero-scroll-indicator {
    position: absolute;
    bottom: 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    font-size: 0.8rem;
    color: var(--text-muted);
    animation: fadeInUp 1s 1.5s both;
}

.hero-scroll-indicator svg {
    animation: bounceDown 2s infinite;
}

@keyframes bounceDown {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(6px); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- Sections --- */
.section {
    padding: 120px 0;
}

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

.section-tag {
    display: inline-block;
    padding: 4px 14px;
    background: rgba(79, 110, 246, 0.1);
    border: 1px solid rgba(79, 110, 246, 0.2);
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 20px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
}

.accent {
    color: var(--accent-light);
}

.section-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.8;
}

/* --- About Section --- */
.about {
    background: var(--bg-secondary);
}

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

.about-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    transition: all 0.3s ease;
}

.about-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-light);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.about-card-icon {
    font-size: 2rem;
    margin-bottom: 20px;
}

.about-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.about-card p {
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 0.95rem;
}

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

.solution-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    transition: all 0.3s ease;
    position: relative;
}

.solution-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-light);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.solution-card.featured {
    border-color: rgba(79, 110, 246, 0.3);
    background: linear-gradient(180deg, rgba(79, 110, 246, 0.08) 0%, var(--bg-card) 40%);
}

.solution-badge {
    position: absolute;
    top: 20px; right: 20px;
    padding: 4px 12px;
    background: var(--gradient-1);
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 700;
    color: #fff;
}

.solution-icon {
    width: 56px; height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(79, 110, 246, 0.1);
    border-radius: var(--radius-md);
    margin-bottom: 24px;
    color: var(--accent-light);
}

.solution-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.solution-card > p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 0.95rem;
    margin-bottom: 20px;
}

.solution-features {
    list-style: none;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

.solution-features li {
    font-size: 0.85rem;
    color: var(--text-secondary);
    padding-left: 18px;
    position: relative;
}

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

/* --- Technology --- */
.technology {
    background: var(--bg-secondary);
}

.tech-stack {
    max-width: 800px;
    margin: 0 auto;
}

.tech-layer {
    margin-bottom: 24px;
    padding: 24px 32px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    display: flex;
    gap: 24px;
    align-items: flex-start;
    transition: all 0.3s ease;
}

.tech-layer:hover {
    background: var(--bg-card-hover);
    border-color: rgba(79, 110, 246, 0.2);
}

.tech-layer-label {
    min-width: 120px;
    font-weight: 700;
    font-size: 0.95rem;
    color: var(--accent-light);
    padding-top: 2px;
}

.tech-items {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech-tag {
    padding: 4px 14px;
    background: rgba(79, 110, 246, 0.08);
    border: 1px solid rgba(79, 110, 246, 0.15);
    border-radius: 50px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.tech-tag:hover {
    background: rgba(79, 110, 246, 0.15);
    color: var(--text-primary);
}

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

.case-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    transition: all 0.3s ease;
}

.case-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-light);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.case-header {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.case-industry, .case-scale {
    padding: 2px 12px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
}

.case-industry {
    background: rgba(79, 110, 246, 0.15);
    color: var(--accent-light);
}

.case-scale {
    background: rgba(124, 77, 255, 0.15);
    color: #b39bff;
}

.case-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.case-card > p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 0.9rem;
    margin-bottom: 24px;
}

.case-results {
    display: flex;
    gap: 16px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

.case-result {
    text-align: center;
    flex: 1;
}

.case-result strong {
    display: block;
    font-size: 1.35rem;
    font-weight: 800;
    color: var(--accent-light);
}

.case-result span {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 2px;
    display: block;
}

/* --- Partners --- */
.partners {
    background: var(--bg-secondary);
}

.partners-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 20px;
}

.partner-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    text-align: center;
    transition: all 0.3s ease;
}

.partner-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-light);
}

.main-partner {
    text-align: left;
}

.main-partner h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.main-partner p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.7;
}

.partner-logo-placeholder {
    width: 100%;
    height: 72px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(79, 110, 246, 0.06);
    border: 1px dashed rgba(79, 110, 246, 0.2);
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
}

.partner-name {
    font-size: 1.3rem;
    font-weight: 800;
}

.partner-sub {
    font-size: 0.65rem;
    letter-spacing: 0.3em;
    color: var(--text-muted);
    margin-top: 2px;
}

.partner-name-sm {
    font-size: 1rem;
    font-weight: 700;
}

.partner-card > p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* --- Contact --- */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 48px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-item {
    display: flex;
    gap: 16px;
    padding: 20px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

.contact-item:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-light);
}

.contact-icon {
    width: 48px; height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(79, 110, 246, 0.1);
    border-radius: var(--radius-sm);
    color: var(--accent-light);
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.contact-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.contact-form-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.form-row {
    display: flex;
    gap: 16px;
}

.form-group {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.form-group label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group textarea {
    padding: 12px 16px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    transition: all 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-group textarea {
    resize: vertical;
}

/* --- Footer --- */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 64px 0 32px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-brand p {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-top: 16px;
    font-size: 0.9rem;
}

.footer-links h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-links a {
    display: block;
    color: var(--text-secondary);
    font-size: 0.85rem;
    padding: 4px 0;
    transition: color 0.2s;
}

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

.footer-links p {
    color: var(--text-secondary);
    font-size: 0.85rem;
    padding: 4px 0;
}

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-bottom p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.footer-beian a {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.footer-beian a:hover {
    color: var(--text-secondary);
}

/* --- Responsive --- */
@media (max-width: 968px) {
    .about-grid,
    .solutions-grid,
    .cases-grid {
        grid-template-columns: 1fr;
    }

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

    .main-partner {
        grid-column: 1 / -1;
    }

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

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

    .hero-stats {
        gap: 32px;
        flex-wrap: wrap;
    }

    .form-row {
        flex-direction: column;
    }

    .tech-layer {
        flex-direction: column;
        gap: 12px;
    }
}

@media (max-width: 640px) {
    .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 16px; right: 16px;
        background: var(--bg-card);
        border: 1px solid var(--border);
        border-radius: var(--radius-lg);
        padding: 16px;
        flex-direction: column;
        box-shadow: var(--shadow-lg);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero {
        padding: 100px 16px 40px;
    }

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

    .hero-stats {
        gap: 20px;
        justify-content: center;
    }

    .stat-number {
        font-size: 1.8rem;
    }

    .section {
        padding: 80px 0;
    }

    .footer-bottom {
        flex-direction: column;
        gap: 8px;
        text-align: center;
    }

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

    .hero-title {
        font-size: 2rem;
    }

    .desktop-only {
        display: none;
    }
}

/* --- Animations --- */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}

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