/* ===== CSS Variables ===== */
:root {
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-bg-card: #ffffff;
    --color-text: #1e293b;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-primary: #6366f1;
    --color-primary-dark: #4f46e5;
    --color-primary-light: #818cf8;
    --color-accent: #f59e0b;
    --color-border: #e2e8f0;
    --color-code-bg: #1e293b;
    --color-code-text: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

[data-theme="dark"] {
    --color-bg: #0f172a;
    --color-bg-alt: #1e293b;
    --color-bg-card: #1e293b;
    --color-text: #f1f5f9;
    --color-text-secondary: #94a3b8;
    --color-text-muted: #64748b;
    --color-border: #334155;
    --color-code-bg: #0f172a;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    transition: var(--transition);
}

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

ul {
    list-style: none;
}

img {
    max-width: 100%;
}

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

/* ===== Navbar ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    font-size: 1.25rem;
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: #fff;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
}

.logo-text {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 28px;
}

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: var(--transition);
    position: relative;
}

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

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

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.theme-toggle:hover {
    border-color: var(--color-primary);
}

.theme-toggle .sun { display: none; }
.theme-toggle .moon { display: block; }

[data-theme="dark"] .theme-toggle .sun { display: block; }
[data-theme="dark"] .theme-toggle .moon { display: none; }

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 100px 24px 40px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(245, 158, 11, 0.1) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-greeting {
    color: var(--color-accent);
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 8px;
}

.hero-title {
    font-size: 3.2rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    margin-bottom: 20px;
}

.hero-description {
    font-size: 1.05rem;
    color: var(--color-text-muted);
    max-width: 500px;
    margin-bottom: 32px;
}

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

/* ===== Stats Card ===== */
.stats-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-xl);
}

.stat-row {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border);
}

.stat-row:last-child {
    border-bottom: none;
}

.stat-icon {
    font-size: 1.5rem;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    min-width: 80px;
}

.stat-label {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

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

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

.btn-secondary {
    background: var(--color-bg-alt);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

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

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
}

.btn-outline:hover {
    background: var(--color-primary);
    color: #fff;
}

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

/* ===== Scroll Indicator ===== */
.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: var(--color-text-muted);
    font-size: 0.85rem;
    animation: bounce 2s infinite;
}

.arrow {
    width: 20px;
    height: 20px;
    border-right: 2px solid var(--color-text-muted);
    border-bottom: 2px solid var(--color-text-muted);
    transform: rotate(45deg);
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
    40% { transform: translateX(-50%) translateY(-10px); }
    60% { transform: translateX(-50%) translateY(-5px); }
}

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

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

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

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

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

/* ===== Services Section ===== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.service-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 28px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

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

.service-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.service-name {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.service-desc {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
    line-height: 1.6;
}

.service-features {
    margin-bottom: 16px;
}

.service-features li {
    padding: 6px 0;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    position: relative;
    padding-left: 20px;
}

.service-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: 600;
}

.service-output {
    background: var(--color-bg-alt);
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--color-primary);
    font-weight: 500;
    margin-bottom: 16px;
}

.service-price {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding-top: 16px;
    border-top: 1px solid var(--color-border);
    margin-top: 4px;
}

.service-price .price-original {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    text-decoration: line-through;
}

.service-price .price-current {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
}

/* ===== Pricing Section ===== */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
    margin-bottom: 32px;
}

.pricing-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
    position: relative;
}

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

.pricing-card.featured {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-xl);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-primary);
    color: #fff;
    padding: 4px 20px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

.pricing-header {
    text-align: center;
    margin-bottom: 20px;
}

.pricing-name {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.pricing-desc {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

.pricing-price {
    text-align: center;
    margin-bottom: 24px;
}

.price-original {
    font-size: 1rem;
    color: var(--color-text-muted);
    text-decoration: line-through;
    margin-right: 12px;
}

.price-current {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-primary);
}

.pricing-features {
    margin-bottom: 20px;
}

.pricing-features li {
    padding: 8px 0;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
}

.pricing-target {
    text-align: center;
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-bottom: 20px;
    padding-top: 16px;
    border-top: 1px solid var(--color-border);
}

.pricing-card .btn {
    width: 100%;
}

.pricing-note {
    text-align: center;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
}

/* ===== Knowledge Section ===== */
.knowledge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.knowledge-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 28px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

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

.knowledge-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.knowledge-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.knowledge-card > p {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
}

.knowledge-detail {
    background: var(--color-bg-alt);
    padding: 16px;
    border-radius: var(--radius-sm);
    margin-top: 16px;
}

.knowledge-detail h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-primary);
}

.knowledge-detail li {
    padding: 6px 0;
    color: var(--color-text-secondary);
    font-size: 0.85rem;
    line-height: 1.5;
}

.knowledge-detail strong {
    color: var(--color-text);
}

/* ===== Team Section ===== */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
    margin-bottom: 48px;
}

.team-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
    text-align: center;
}

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

.team-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    font-weight: 700;
    margin: 0 auto 20px;
}

.team-name {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.team-role {
    color: var(--color-primary);
    font-size: 0.95rem;
    font-weight: 500;
    margin-bottom: 16px;
}

.team-desc {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 20px;
}

.team-skills {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}

.skill-tag {
    padding: 6px 14px;
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: 20px;
    font-size: 0.85rem;
    color: var(--color-text-secondary);
    font-family: 'JetBrains Mono', monospace;
    transition: var(--transition);
}

.skill-tag:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.team-value {
    text-align: center;
    background: var(--color-bg);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
}

.team-value h3 {
    font-size: 1.3rem;
    margin-bottom: 12px;
}

.team-value p {
    color: var(--color-text-secondary);
    font-size: 1.05rem;
    line-height: 1.8;
}

.team-value strong {
    color: var(--color-primary);
}

/* ===== Process Section ===== */
.process-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.process-item {
    display: flex;
    gap: 24px;
    padding: 24px 0;
    border-bottom: 1px solid var(--color-border);
}

.process-item:last-child {
    border-bottom: none;
}

.process-number {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
    flex-shrink: 0;
}

.process-content h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.process-content p {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

/* ===== Promise Section ===== */
.promise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 32px;
}

.promise-item {
    text-align: center;
    padding: 24px;
}

.promise-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: 16px;
}

.promise-item h4 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.promise-item p {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

/* ===== Contact Section ===== */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: start;
}

.contact-item {
    display: flex;
    gap: 16px;
    padding: 24px;
    background: var(--color-bg-alt);
    border-radius: var(--radius-md);
    margin-bottom: 16px;
}

.contact-icon {
    font-size: 2rem;
}

.contact-text h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.contact-text p {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    margin-bottom: 4px;
}

.contact-highlight {
    color: var(--color-primary);
    font-weight: 500;
}

.cta-box {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    padding: 48px;
    border-radius: var(--radius-lg);
    text-align: center;
    color: #fff;
}

.cta-box h3 {
    font-size: 1.5rem;
    margin-bottom: 12px;
}

.cta-box > p {
    opacity: 0.9;
    margin-bottom: 24px;
}

.cta-box .btn-primary {
    background: #fff;
    color: var(--color-primary);
}

.cta-box .btn-primary:hover {
    background: var(--color-bg-alt);
}

.cta-note {
    margin-top: 16px;
    font-size: 0.85rem;
    opacity: 0.8;
}

/* ===== Footer ===== */
.footer {
    background: var(--color-code-bg);
    color: var(--color-code-text);
    padding: 48px 0;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    font-size: 1.25rem;
}

.footer-brand .logo-icon {
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
}

.footer-links {
    display: flex;
    gap: 32px;
}

.footer-links a {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    transition: var(--transition);
}

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

.footer-copyright {
    text-align: center;
}

.footer-copyright p {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-bottom: 4px;
}

.footer-slogan {
    color: var(--color-primary-light);
    font-style: italic;
}

/* ===== Back to Top ===== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
}

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

.back-to-top:hover {
    transform: translateY(-4px);
    background: var(--color-primary-dark);
}

/* ===== Responsive Design ===== */
@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-description {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-cta {
        justify-content: center;
    }

    .hero-visual {
        display: none;
    }

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

    .nav-links {
        display: none;
    }
}

@media (max-width: 640px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .section {
        padding: 60px 0;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .services-grid,
    .pricing-grid,
    .knowledge-grid,
    .team-grid {
        grid-template-columns: 1fr;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }

    .cta-box {
        padding: 32px 24px;
    }
}