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

:root {
    --bg: #06060a;
    --bg-card: #0e0e14;
    --bg-card-hover: #14141c;
    --border: #1e1e2a;
    --border-light: #2a2a3a;
    --text: #f0f0f5;
    --text-muted: #8888a0;
    --primary: #6366f1;
    --primary-light: #818cf8;
    --primary-dim: rgba(99,102,241,0.08);
    --accent: #38bdf8;
    --gradient: linear-gradient(135deg, #6366f1 0%, #38bdf8 100%);
    --gradient-soft: linear-gradient(135deg, rgba(99,102,241,0.15) 0%, rgba(56,189,248,0.15) 100%);
    --radius: 16px;
    --radius-sm: 10px;
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }
a { color: inherit; text-decoration: none; }

/* ========== Navbar ========== */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    padding: 18px 0;
    transition: all 0.35s ease;
    background: transparent;
}
.navbar.scrolled {
    background: rgba(6,6,10,0.9);
    backdrop-filter: blur(24px);
    border-bottom: 1px solid var(--border);
    padding: 12px 0;
}
.nav-content { display: flex; align-items: center; justify-content: space-between; }
.logo { display: flex; align-items: center; }
.nav-logo { height: 30px; width: auto; }
.nav-right { display: flex; align-items: center; gap: 32px; }
.nav-links { display: flex; list-style: none; gap: 32px; }
.nav-links a {
    font-size: 0.88rem; color: var(--text-muted);
    transition: color 0.25s; font-weight: 500;
    position: relative;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: -4px; left: 0;
    width: 0; height: 1.5px; background: var(--gradient);
    transition: width 0.3s;
}
.nav-links a:hover { color: var(--text); }
.nav-links a:hover::after { width: 100%; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; flex-direction: column; gap: 5px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); transition: 0.3s; border-radius: 2px; }
.nav-download-wrap { position: relative; }
.mobile-download-btn { display: none; }
.mobile-download-section { display: none; }
.nav-download-btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 8px 20px; border-radius: 100px; border: none;
    background: var(--gradient);
    color: #fff; font-size: 0.85rem; font-weight: 600;
    transition: all 0.3s ease; cursor: pointer;
    white-space: nowrap;
}
.nav-download-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(99,102,241,0.35);
}
.download-dropdown {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 8px;
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.25s ease;
    z-index: 200;
    box-shadow: 0 12px 40px rgba(0,0,0,0.4);
}
.download-dropdown.open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.download-option {
    display: flex; align-items: center; gap: 12px;
    padding: 12px 14px; border-radius: 8px;
    text-decoration: none; color: var(--text);
    transition: background 0.2s;
}
.download-option:hover:not(.disabled) { background: var(--bg-card-hover); }
.download-option.disabled {
    opacity: 0.45; cursor: default;
}
.download-icon { font-size: 1.3rem; flex-shrink: 0; width: 28px; text-align: center; }
.download-option strong { display: block; font-size: 0.88rem; font-weight: 600; }
.download-option small { font-size: 0.75rem; color: var(--text-muted); }

/* ========== Hero ========== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex; align-items: center; justify-content: center;
    text-align: center;
    padding: 120px 0 80px;
    overflow: hidden;
}
.hero-bg { position: absolute; inset: 0; z-index: 0; }
.gradient-orb {
    position: absolute; border-radius: 50%; filter: blur(140px);
}
.orb-1 { width: 700px; height: 700px; background: var(--primary); top: -250px; right: -150px; opacity: 0.12; }
.orb-2 { width: 500px; height: 500px; background: var(--accent); bottom: -200px; left: -100px; opacity: 0.08; }
.orb-3 { width: 350px; height: 350px; background: #818cf8; top: 30%; left: 45%; opacity: 0.06; }
.grid-overlay {
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.015) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.015) 1px, transparent 1px);
    background-size: 80px 80px;
}
.hero-content { position: relative; z-index: 2; }
.hero-logo {
    position: absolute;
    width: 80%;
    height: 80%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    object-fit: contain;
    opacity: 0.3;
    z-index: 0;
    pointer-events: none;
}
.hero-badge {
    display: inline-block;
    padding: 8px 22px;
    border-radius: 100px;
    background: rgba(56,189,248,0.1);
    border: 1px solid rgba(56,189,248,0.25);
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 36px;
    letter-spacing: 0.3px;
}
.hero-title {
    font-size: clamp(2.4rem, 5.5vw, 4.2rem);
    font-weight: 800; line-height: 1.2;
    margin-bottom: 28px;
    letter-spacing: -0.5px;
}
.gradient-text {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-desc {
    font-size: 1.05rem;
    color: #b0b0c0;
    max-width: 560px;
    margin: 0 auto 48px;
    line-height: 1.9;
}

/* Stats */
.hero-stats { display: flex; justify-content: center; gap: 72px; }
.stat { text-align: center; }
.stat-num {
    font-size: 2.8rem; font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -1px;
}
.stat-suffix {
    font-size: 1.4rem; font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.stat-label {
    display: block;
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-top: 6px;
    font-weight: 400;
}

/* ========== Sections ========== */
section { padding: 110px 0; }
.section-header { text-align: center; margin-bottom: 72px; }
.section-tag {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 3px;
    color: var(--primary-light);
    margin-bottom: 16px;
    text-transform: uppercase;
}
.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 18px;
    letter-spacing: -0.3px;
}
.section-desc {
    color: var(--text-muted);
    max-width: 520px;
    margin: 0 auto;
    font-size: 0.98rem;
    line-height: 1.7;
}

/* ========== About ========== */
.about { background: var(--bg); }
.about-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.about-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px 30px;
    transition: all 0.35s ease;
    position: relative;
    overflow: hidden;
}
.about-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0;
    height: 2px;
    background: var(--gradient);
    opacity: 0;
    transition: opacity 0.35s;
}
.about-card:hover {
    border-color: var(--border-light);
    transform: translateY(-4px);
    background: var(--bg-card-hover);
    box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.about-card:hover::before { opacity: 1; }
.about-icon { font-size: 2rem; margin-bottom: 22px; }
.about-card h3 { font-size: 1.15rem; margin-bottom: 14px; font-weight: 600; }
.about-card p { color: var(--text-muted); font-size: 0.92rem; line-height: 1.75; }

/* About 简介 & 联系同行 */
.about-intro-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 22px;
    margin-bottom: 22px;
}
.about-intro-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px 30px;
    transition: all 0.35s ease;
}
.about-intro-card:hover {
    border-color: var(--border-light);
    box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.about-intro-card h3 {
    font-size: 1.15rem;
    margin-bottom: 18px;
    font-weight: 600;
}
.about-intro-card > p {
    color: var(--text-muted);
    font-size: 0.92rem;
    line-height: 1.8;
}
.intro-contact-list {
    display: flex;
    flex-direction: column;
    gap: 18px;
}
.intro-contact-item {
    display: flex;
    gap: 14px;
    align-items: flex-start;
}
.intro-contact-item > span {
    font-size: 1.2rem;
    flex-shrink: 0;
    margin-top: 2px;
}
.intro-contact-item strong {
    display: block;
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 3px;
}
.intro-contact-item p {
    color: var(--text);
    font-size: 0.92rem;
    line-height: 1.5;
    margin: 0;
}

/* ========== Demo Videos ========== */
.demo {
    background: linear-gradient(180deg, var(--bg) 0%, #08080e 50%, var(--bg) 100%);
}
.demo-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; }
.demo-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: all 0.35s ease;
}
.demo-card:hover {
    border-color: var(--border-light);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.demo-card-wide { grid-column: span 2; }
.demo-label {
    padding: 16px 22px 14px;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--text-muted);
    border-bottom: 1px solid var(--border);
    letter-spacing: 0.3px;
}
.demo-compare-labels {
    position: relative;
    padding: 14px 22px 10px;
}
.demo-compare-labels span {
    position: absolute;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    transform: translateX(-50%);
}
.demo-compare-labels span:first-child { left: 33%; }
.demo-compare-labels span:last-child { left: 67%; }
.demo-video-wrap {
    position: relative;
    display: flex !important;
    justify-content: center !important;
    align-items: flex-start !important;
    padding: 18px;
    cursor: pointer;
}
.demo-video-wrap video {
    display: block !important;
    width: auto !important;
    max-width: 100% !important;
    height: auto !important;
    border-radius: var(--radius-sm);
    margin: 0 auto !important;
}
/* Custom controls */
.custom-controls {
    position: absolute;
    bottom: 18px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 10px;
    background: rgba(0,0,0,0.75);
    backdrop-filter: blur(10px);
    padding: 8px 16px;
    border-radius: 100px;
    opacity: 0;
    transition: opacity 0.3s;
    width: calc(100% - 60px);
    max-width: 480px;
    border: 1px solid rgba(255,255,255,0.06);
}
.demo-video-wrap:hover .custom-controls { opacity: 1; }
.ctrl-btn {
    background: none; border: none; color: #fff; font-size: 0.82rem;
    cursor: pointer; padding: 4px 6px; line-height: 1; flex-shrink: 0;
    transition: color 0.2s;
}
.ctrl-btn:hover { color: var(--accent); }
.ctrl-progress {
    flex: 1; height: 3px; -webkit-appearance: none; appearance: none;
    background: rgba(255,255,255,0.2); border-radius: 2px; outline: none;
    cursor: pointer;
}
.ctrl-progress::-webkit-slider-thumb {
    -webkit-appearance: none; width: 11px; height: 11px;
    background: #fff; border-radius: 50%; cursor: pointer;
}
.ctrl-progress::-moz-range-thumb {
    width: 11px; height: 11px; border: none;
    background: #fff; border-radius: 50%; cursor: pointer;
}
.ctrl-time {
    font-size: 0.72rem; color: rgba(255,255,255,0.55);
    white-space: nowrap; flex-shrink: 0; font-variant-numeric: tabular-nums;
}
/* Video loading spinner */
.video-loading {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    display: none;
    z-index: 5;
}
.video-loading.show { display: block; }
.spinner {
    width: 36px; height: 36px;
    border: 3px solid rgba(255,255,255,0.15);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ========== Workflow ========== */
.workflow { background: var(--bg); }
.workflow-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.workflow-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: all 0.35s ease;
}
.workflow-card:hover {
    border-color: var(--border-light);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.workflow-img {
    width: 100%;
    aspect-ratio: 9/14;
    overflow: hidden;
    background: #0a0a10;
}
.workflow-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}
.workflow-card-content {
    padding: 24px 22px;
}
.workflow-card-content .step-number {
    font-size: 1.6rem;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -1px;
    margin-bottom: 8px;
}
.workflow-card-content h3 { font-size: 1.08rem; margin-bottom: 8px; font-weight: 600; }
.workflow-card-content p { color: var(--text-muted); font-size: 0.88rem; line-height: 1.7; }

/* ========== Contact (legacy, kept for reference) ========== */

/* ========== Footer ========== */
.footer {
    border-top: 1px solid var(--border);
    padding: 52px 0 32px;
    background: var(--bg);
}
.footer-content { display: flex; justify-content: space-between; margin-bottom: 44px; }
.footer-brand p { color: var(--text-muted); margin-top: 10px; font-size: 0.88rem; }
.footer-logo { height: 26px; width: auto; }
.footer-links { display: flex; gap: 72px; }
.footer-col { display: flex; flex-direction: column; gap: 12px; }
.footer-col h4 { font-size: 0.82rem; margin-bottom: 4px; color: var(--text-muted); font-weight: 600; letter-spacing: 0.5px; }
.footer-col a { font-size: 0.88rem; color: var(--text-muted); transition: color 0.25s; }
.footer-col a:hover { color: var(--text); }
.footer-bottom {
    text-align: center;
    padding-top: 28px;
    border-top: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}
.footer-bottom-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}
.footer-bottom-logo { height: 24px; width: auto; }
.footer-slogan { font-size: 0.85rem; color: var(--text-muted); margin: 0; }
.footer-bottom-info { display: flex; gap: 24px; flex-wrap: wrap; justify-content: center; }
.footer-bottom-info p { font-size: 0.78rem; color: var(--text-muted); margin: 0; }
.footer-bottom-info a { color: var(--text-muted); text-decoration: none; transition: color 0.2s; }
.footer-bottom-info a:hover { color: var(--text); }

/* ========== Animations ========== */
.fade-up {
    opacity: 0; transform: translateY(28px);
    transition: opacity 0.65s ease, transform 0.65s ease;
}
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* ========== Responsive ========== */
@media (max-width: 768px) {
    .nav-right { position: static; }
    .nav-links { display: none; }
    .nav-links.open {
        display: flex; flex-direction: column;
        position: absolute; top: 100%; left: 0; right: 0;
        background: rgba(6,6,10,0.95); backdrop-filter: blur(24px);
        padding: 24px; gap: 20px; border-bottom: 1px solid var(--border);
    }
    .nav-toggle { display: flex; }
    .nav-download-wrap { display: none; }
    .mobile-download-section {
        display: block;
        margin-top: 8px;
        padding-top: 16px;
        border-top: 1px solid var(--border);
    }
    .mobile-download-option {
        display: flex; align-items: center; gap: 12px;
        padding: 12px 14px; border-radius: 8px;
        text-decoration: none; color: var(--text);
        transition: background 0.2s;
    }
    .mobile-download-option:hover:not(.disabled) { background: var(--bg-card-hover); }
    .mobile-download-option.disabled {
        opacity: 0.45; cursor: default;
    }
    .mobile-download-option strong { display: block; font-size: 0.88rem; font-weight: 600; }
    .mobile-download-option small { font-size: 0.75rem; color: var(--text-muted); }
    .hero-stats { flex-direction: column; gap: 28px; }
    .about-grid { grid-template-columns: 1fr; }
    .about-intro-grid { grid-template-columns: 1fr; }
    .demo-grid { grid-template-columns: 1fr; }
    .demo-card-wide { grid-column: span 1; }
    .workflow-grid { grid-template-columns: 1fr; }
    .contact-wrapper { grid-template-columns: 1fr; gap: 40px; }
    .footer-content { flex-direction: column; gap: 36px; }
    .footer-links { gap: 40px; }
    .hero-title { font-size: 2rem; }
    section { padding: 80px 0; }
}