/* ============================================
   广州星河渊科技有限公司 - 官网样式
   配色: 深色背景 + 金色强调 + 星空感
   ============================================ */

/* ---------- CSS Variables ---------- */
:root {
    --bg-primary: #0A0A0F;
    --bg-secondary: #1A1A2E;
    --bg-card: #12121f;
    --bg-card-hover: #1a1a30;
    --gold: #D4AF37;
    --gold-light: #FFD700;
    --gold-glow: rgba(212, 175, 55, 0.3);
    --text-primary: #FFFFFF;
    --text-secondary: #E8E8E8;
    --text-muted: #8A8A9A;
    --blue-accent: #4A6CF7;
    --border-subtle: rgba(255, 255, 255, 0.06);
    --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --max-width: 1200px;
}

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

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

body {
    font-family: var(--font-family);
    background: var(--bg-primary);
    color: var(--text-secondary);
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

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

/* ---------- Starfield Canvas ---------- */
#starfield {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ---------- Navigation ---------- */
#navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 20px 0;
    transition: all var(--transition);
}

#navbar.scrolled {
    background: rgba(10, 10, 15, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 12px 0;
    border-bottom: 1px solid var(--border-subtle);
}

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

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

.nav-logo img {
    width: 42px;
    height: 42px;
    object-fit: contain;
    border-radius: 8px;
}

.nav-brand {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}

.brand-cn {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 2px;
}

.brand-en {
    font-size: 10px;
    font-weight: 400;
    color: var(--gold);
    letter-spacing: 3px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 36px;
}

.nav-links a {
    font-size: 14px;
    font-weight: 400;
    color: var(--text-muted);
    transition: color var(--transition);
    position: relative;
    letter-spacing: 1px;
}

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

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

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

.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);
}

/* ---------- Section Common ---------- */
section {
    position: relative;
    z-index: 1;
    padding: 120px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 72px;
}

.section-tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 4px;
    color: var(--gold);
    margin-bottom: 16px;
    text-transform: uppercase;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 2px;
    margin-bottom: 20px;
}

.section-divider {
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--gold), var(--gold-light));
    margin: 0 auto;
    border-radius: 2px;
}

/* ---------- Hero Section ---------- */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 24px;
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 800px;
}

.hero-title {
    margin-bottom: 28px;
}

.title-line {
    display: block;
    font-size: clamp(40px, 7vw, 72px);
    font-weight: 900;
    color: var(--text-primary);
    letter-spacing: 8px;
    line-height: 1.1;
    background: linear-gradient(135deg, #FFFFFF 0%, #E8E8E8 40%, var(--gold) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.title-sub {
    display: block;
    font-size: clamp(12px, 2vw, 16px);
    font-weight: 300;
    letter-spacing: 10px;
    color: var(--gold);
    margin-top: 12px;
    -webkit-text-fill-color: var(--gold);
}

.hero-slogan {
    font-size: clamp(18px, 3vw, 24px);
    font-weight: 300;
    color: var(--text-secondary);
    letter-spacing: 4px;
    margin-bottom: 16px;
}

.hero-desc {
    font-size: 14px;
    color: var(--text-muted);
    letter-spacing: 2px;
    margin-bottom: 48px;
}

.btn-primary {
    display: inline-block;
    padding: 14px 48px;
    border: 1px solid var(--gold);
    color: var(--gold);
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 3px;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: var(--gold);
    transition: left var(--transition);
    z-index: -1;
}

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

.btn-primary:hover::before {
    left: 0;
}

.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    animation: float 3s ease-in-out infinite;
}

.scroll-indicator span {
    font-size: 11px;
    color: var(--text-muted);
    letter-spacing: 2px;
}

.scroll-arrow {
    width: 20px;
    height: 20px;
    border-right: 2px solid var(--gold);
    border-bottom: 2px solid var(--gold);
    transform: rotate(45deg);
    animation: scrollBounce 2s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(-10px); }
}

@keyframes scrollBounce {
    0%, 100% { opacity: 1; transform: rotate(45deg) translate(0, 0); }
    50% { opacity: 0.5; transform: rotate(45deg) translate(4px, 4px); }
}

/* ---------- About Section ---------- */
#about {
    background: linear-gradient(180deg, transparent 0%, rgba(26, 26, 46, 0.4) 50%, transparent 100%);
}

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

.about-text {
    padding-right: 20px;
}

.about-lead {
    font-size: 20px;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 20px;
    line-height: 1.8;
}

.about-lead strong {
    color: var(--gold);
}

.about-text p {
    margin-bottom: 16px;
    color: var(--text-muted);
    line-height: 1.9;
}

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

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 16px;
    padding: 28px 20px;
    text-align: center;
    transition: all var(--transition);
}

.stat-card:hover {
    border-color: rgba(212, 175, 55, 0.3);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(212, 175, 55, 0.08);
}

.stat-icon {
    width: 40px;
    height: 40px;
    margin: 0 auto 16px;
    color: var(--gold);
}

.stat-icon svg {
    width: 100%;
    height: 100%;
}

.stat-number {
    font-size: 36px;
    font-weight: 900;
    color: var(--gold);
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 13px;
    color: var(--text-muted);
    letter-spacing: 1px;
}

/* ---------- Services Section ---------- */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.service-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 20px;
    padding: 40px 28px;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

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

.service-card:hover {
    border-color: rgba(212, 175, 55, 0.2);
    background: var(--bg-card-hover);
    transform: translateY(-8px);
    box-shadow: 0 20px 60px rgba(212, 175, 55, 0.06);
}

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

.service-icon {
    width: 56px;
    height: 56px;
    color: var(--gold);
    margin-bottom: 24px;
}

.service-icon svg {
    width: 100%;
    height: 100%;
}

.service-card h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 14px;
    letter-spacing: 1px;
}

.service-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.8;
}

/* ---------- Advantages Section ---------- */
#advantages {
    background: linear-gradient(180deg, transparent 0%, rgba(26, 26, 46, 0.4) 50%, transparent 100%);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
}

.advantage-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 20px;
    padding: 44px 36px;
    transition: all var(--transition);
    position: relative;
}

.advantage-card:hover {
    border-color: rgba(212, 175, 55, 0.2);
    transform: translateY(-4px);
}

.advantage-number {
    font-size: 64px;
    font-weight: 900;
    color: rgba(212, 175, 55, 0.08);
    position: absolute;
    top: 20px;
    right: 28px;
    line-height: 1;
}

.advantage-card h3 {
    font-size: 22px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
    letter-spacing: 1px;
}

.advantage-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.9;
    max-width: 420px;
}

/* ---------- Contact Section ---------- */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.contact-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 20px;
    padding: 40px 28px;
    text-align: center;
    transition: all var(--transition);
}

.contact-card:hover {
    border-color: rgba(212, 175, 55, 0.2);
    transform: translateY(-4px);
}

.contact-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 20px;
    color: var(--gold);
}

.contact-icon svg {
    width: 100%;
    height: 100%;
}

.contact-card h3 {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 14px;
    letter-spacing: 1px;
}

.contact-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.8;
}

/* ---------- Footer ---------- */
footer {
    position: relative;
    z-index: 1;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-subtle);
    padding: 48px 0 24px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border-subtle);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 14px;
}

.footer-logo {
    width: 42px;
    height: 42px;
    object-fit: contain;
    border-radius: 8px;
}

.footer-name {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 1px;
}

.footer-en {
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 2px;
}

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

.footer-links a {
    font-size: 13px;
    color: var(--text-muted);
    transition: color var(--transition);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-bottom p {
    font-size: 12px;
    color: var(--text-muted);
}

.footer-bottom a {
    color: var(--text-muted);
    transition: color var(--transition);
}

.footer-bottom a:hover {
    color: var(--gold);
}

/* ---------- Reveal Animation ---------- */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1),
                transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .about-text {
        padding-right: 0;
    }

    .section-title {
        font-size: 30px;
    }
}

@media (max-width: 768px) {
    section {
        padding: 80px 0;
    }

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

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: rgba(10, 10, 15, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        transition: right var(--transition);
    }

    .nav-links.open {
        right: 0;
    }

    .nav-links a {
        font-size: 18px;
    }

    .nav-toggle {
        display: flex;
        z-index: 1001;
    }

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

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

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

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

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

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

    .section-title {
        font-size: 26px;
    }

    .title-line {
        letter-spacing: 4px;
    }

    .title-sub {
        letter-spacing: 5px;
    }

    .advantage-card {
        padding: 32px 24px;
    }
}

@media (max-width: 480px) {
    .about-stats {
        grid-template-columns: 1fr;
    }

    .hero-slogan {
        letter-spacing: 2px;
    }

    .stat-number {
        font-size: 28px;
    }
}