/* ==================== Reset & Base ==================== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
    color: #1a1a2e; line-height: 1.7; background: #fafafa;
    -webkit-font-smoothing: antialiased;
}
a { color: #e8600a; text-decoration: none; transition: color .2s; }
a:hover { color: #c84e00; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

:root {
    --orange-primary: #e8600a;
    --orange-dark: #c84e00;
    --orange-light: #ff8c42;
    --orange-bg: #fff5ec;
    --orange-bg2: #fff0e0;
    --orange-gradient: linear-gradient(135deg, #ff8c42 0%, #e8600a 50%, #c84e00 100%);
    --text-primary: #1a1a2e;
    --text-secondary: #555;
    --text-light: #888;
    --white: #fff;
    --gray-50: #fafafa;
    --gray-100: #f5f5f5;
    --gray-200: #e5e5e5;
    --gray-800: #333;
    --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
    --shadow-md: 0 4px 16px rgba(0,0,0,.1);
    --shadow-lg: 0 8px 32px rgba(0,0,0,.12);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --max-width: 1100px;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }

/* ==================== Navbar ==================== */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,.92); backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(232,96,10,.08);
    transition: box-shadow .3s;
}
.navbar.scrolled { box-shadow: var(--shadow-sm); }
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.navbar-brand { display: flex; align-items: center; gap: 10px; font-size: 1.15rem; font-weight: 700; color: var(--orange-primary); }
.navbar-logo { width: 32px; height: 32px; border-radius: 8px; object-fit: contain; }
.nav-links { display: flex; align-items: center; gap: 24px; }
.nav-links a { color: var(--text-secondary); font-size: .9rem; font-weight: 500; }
.nav-links a:hover { color: var(--orange-primary); }
.nav-btn {
    background: var(--orange-gradient); color: #fff !important;
    padding: 8px 18px; border-radius: 50px; font-weight: 600; font-size: .85rem;
    box-shadow: 0 2px 10px rgba(232,96,10,.25); transition: transform .2s, box-shadow .2s;
}
.nav-btn:hover { transform: translateY(-1px); box-shadow: 0 4px 16px rgba(232,96,10,.35); color: #fff !important; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--gray-800); margin: 5px 0; transition: .3s; border-radius: 2px; }

/* ==================== Hero ==================== */
.hero {
    padding: 140px 20px 60px; text-align: center;
    background: linear-gradient(180deg, var(--orange-bg) 0%, #fff 100%);
    position: relative; overflow: hidden;
}
.hero::before {
    content: ''; position: absolute; top: -200px; right: -200px;
    width: 500px; height: 500px; background: radial-gradient(circle, rgba(232,96,10,.06) 0%, transparent 70%);
    border-radius: 50%;
}
.hero-inner { position: relative; z-index: 1; max-width: 700px; margin: 0 auto; }
.hero-badge {
    display: inline-flex; align-items: center; gap: 6px;
    background: var(--orange-bg2); color: var(--orange-dark);
    padding: 5px 14px; border-radius: 50px; font-size: .8rem; font-weight: 600;
    margin-bottom: 20px; border: 1px solid rgba(232,96,10,.15);
}
.hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.5rem); font-weight: 800;
    line-height: 1.2; color: var(--text-primary); margin-bottom: 16px;
}
.hero h1 .highlight {
    background: var(--orange-gradient); -webkit-background-clip: text;
    -webkit-text-fill-color: transparent; background-clip: text;
}
.hero-desc { font-size: clamp(1rem, 2vw, 1.15rem); color: var(--text-secondary); margin-bottom: 32px; line-height: 1.7; }
.hero-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-bottom: 28px; }
.hero-install-cmd {
    max-width: 480px; margin: 0 auto 40px; text-align: left;
    background: #1e1e2e; border-radius: var(--radius-md); overflow: hidden;
}
.cmd-label { padding: 8px 16px; font-size: .75rem; color: #888; background: rgba(255,255,255,.05); }
.cmd-code {
    padding: 12px 16px; font-family: "SF Mono", "Fira Code", "Consolas", monospace;
    font-size: .85rem; color: #a6e3a1; overflow-x: auto;
}
.cmd-prompt { color: #89b4fa; margin-right: 8px; }
.hero-stats { display: flex; justify-content: center; gap: 36px; padding-top: 24px; border-top: 1px solid var(--gray-200); }
.hero-stat .num { font-size: 1.4rem; font-weight: 800; color: var(--orange-primary); }
.hero-stat .label { font-size: .8rem; color: var(--text-light); margin-top: 2px; }

/* ==================== Buttons ==================== */
.btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 12px 24px; border-radius: 50px; font-size: .9rem; font-weight: 600;
    border: none; cursor: pointer; transition: all .2s; text-decoration: none;
}
.btn-primary {
    background: var(--orange-gradient); color: #fff;
    box-shadow: 0 4px 14px rgba(232,96,10,.3);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(232,96,10,.4); color: #fff; }
.btn-primary svg { width: 18px; height: 18px; fill: currentColor; flex-shrink: 0; }
.btn-outline {
    background: transparent; color: var(--orange-primary);
    border: 2px solid var(--orange-primary);
}
.btn-outline:hover { background: var(--orange-bg); }
.btn-outline:hover { background: var(--orange-bg); }
.btn-cta {
    background: #fff; color: var(--orange-primary); font-weight: 700;
    box-shadow: 0 4px 16px rgba(0,0,0,.15);
}
.btn-cta:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,.2); color: var(--orange-dark); }

/* ==================== Download Buttons ==================== */
.install-download { text-align: center; margin-top: 48px; }
.install-download .download-group { margin-top: 8px; }
.download-group { display: flex; gap: 10px; justify-content: center; flex-wrap: nowrap; margin-top: 24px; }
.download-group .dl-btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 12px 22px; border-radius: 50px; white-space: nowrap;
    font-size: .88rem; font-weight: 600; color: #fff;
    border: none; cursor: pointer; transition: all .2s; text-decoration: none;
}
.dl-btn svg { width: 18px; height: 18px; fill: currentColor; flex-shrink: 0; }
.dl-btn-primary { background: var(--orange-gradient); box-shadow: 0 4px 12px rgba(232,96,10,.3); }
.dl-btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(232,96,10,.45); color: #fff; }
.dl-btn-secondary { background: var(--gray-800); box-shadow: 0 4px 12px rgba(0,0,0,.2); }
.dl-btn-secondary:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,.35); color: #fff; }
.dl-group-label { font-size: .85rem; color: var(--text-light); margin-bottom: 4px; font-weight: 500; }

/* ==================== Section Common ==================== */
section { padding: 70px 0; }
.section-tag {
    display: inline-block; background: var(--orange-bg2); color: var(--orange-dark);
    padding: 4px 14px; border-radius: 50px; font-size: .8rem; font-weight: 600;
    margin-bottom: 10px; letter-spacing: .5px;
}
.section-title { font-size: clamp(1.5rem, 4vw, 2.2rem); font-weight: 800; color: var(--text-primary); margin-bottom: 12px; line-height: 1.3; }
.section-desc { font-size: 1rem; color: var(--text-secondary); max-width: 580px; margin-bottom: 40px; }
.section-header { text-align: center; }
.section-header .section-desc { margin-left: auto; margin-right: auto; }

/* ==================== Features ==================== */
.features { background: #fff; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-card {
    background: #fff; border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg); padding: 28px;
    transition: all .3s; position: relative; overflow: hidden;
}
.feature-card:hover { border-color: var(--orange-primary); box-shadow: var(--shadow-lg); transform: translateY(-3px); }
.feature-card::after {
    content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
    background: var(--orange-gradient); opacity: 0; transition: opacity .3s;
}
.feature-card:hover::after { opacity: 1; }
.feature-icon {
    width: 48px; height: 48px; border-radius: 12px;
    background: var(--orange-bg); display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; margin-bottom: 16px;
}
.feature-card h3 { font-size: 1.1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.feature-card p { font-size: .9rem; color: var(--text-secondary); line-height: 1.65; }

/* ==================== Connect / Platforms ==================== */
.connect { background: var(--gray-50); }
.platform-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 14px; }
.platform-item {
    background: #fff; border-radius: var(--radius-md); padding: 22px 10px;
    text-align: center; border: 1px solid var(--gray-200);
    transition: all .3s; font-size: .9rem; font-weight: 500;
}
.platform-item:hover { box-shadow: var(--shadow-md); border-color: var(--orange-light); transform: translateY(-2px); }
.platform-icon { font-size: 1.8rem; margin-bottom: 8px; }

/* ==================== Architecture ==================== */
.arch { background: #fff; }
.arch-diagram {
    max-width: 700px; margin: 0 auto 40px;
    background: #1e1e2e; border-radius: var(--radius-lg); padding: 32px 24px;
    text-align: center;
}
.arch-top { color: #a6e3a1; font-size: .9rem; padding: 10px 0; }
.arch-arrow { font-size: 1.5rem; color: #f38ba8; margin: 4px 0; }
.arch-gateway {
    background: rgba(232,96,10,.15); border: 2px solid var(--orange-primary);
    border-radius: var(--radius-md); padding: 20px; margin: 8px 0;
}
.arch-gw-title { font-size: 1.1rem; font-weight: 700; color: #fff; }
.arch-gw-sub { font-size: .85rem; color: var(--orange-light); margin-top: 4px; font-family: monospace; }
.arch-split { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin-top: 12px; }
.arch-branch {
    background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1);
    border-radius: var(--radius-sm); padding: 16px 8px;
}
.branch-icon { font-size: 1.4rem; margin-bottom: 6px; }
.branch-title { font-size: .85rem; font-weight: 600; color: #fff; }
.branch-desc { font-size: .75rem; color: #888; margin-top: 2px; }
.arch-features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; max-width: 800px; margin: 0 auto; }
.arch-feat-card {
    background: var(--orange-bg); border: 1px solid var(--gray-200);
    border-radius: var(--radius-md); padding: 20px; text-align: center;
}
.arch-feat-card h4 { font-size: 1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 6px; }
.arch-feat-card p { font-size: .85rem; color: var(--text-secondary); }

/* ==================== History / Timeline ==================== */
.history { background: var(--gray-50); }
.timeline { max-width: 600px; margin: 0 auto; position: relative; }
.timeline::before {
    content: ''; position: absolute; left: 18px; top: 0; bottom: 0;
    width: 3px; background: var(--orange-light); border-radius: 3px;
}
.timeline-item { position: relative; padding: 0 0 40px 52px; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-dot {
    position: absolute; left: 10px; top: 4px;
    width: 20px; height: 20px; border-radius: 50%;
    background: var(--orange-primary); border: 3px solid #fff;
    box-shadow: 0 0 0 2px var(--orange-primary);
}
.timeline-date { font-size: .8rem; font-weight: 600; color: var(--orange-primary); margin-bottom: 4px; }
.timeline-content h3 { font-size: 1.1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 6px; }
.timeline-content p { font-size: .9rem; color: var(--text-secondary); line-height: 1.6; }
.timeline-quote {
    max-width: 550px; margin: 32px auto 0; text-align: center;
    background: var(--orange-bg); border-left: 4px solid var(--orange-primary);
    padding: 24px; border-radius: var(--radius-md);
}
.timeline-quote p { font-size: 1rem; color: var(--text-secondary); font-style: italic; margin-bottom: 10px; }
.timeline-quote cite { font-size: .85rem; color: var(--text-light); font-style: normal; }

/* ==================== Skills ==================== */
.skills { background: #fff; }
.skills-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.skill-card {
    background: #fff; border: 1px solid var(--gray-200);
    border-radius: var(--radius-md); padding: 24px; text-align: center;
    transition: all .3s;
}
.skill-card:hover { border-color: var(--orange-primary); box-shadow: var(--shadow-md); transform: translateY(-2px); }
.skill-icon { font-size: 2rem; margin-bottom: 12px; }
.skill-card h3 { font-size: 1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 6px; }
.skill-card p { font-size: .85rem; color: var(--text-secondary); line-height: 1.6; }

/* ==================== Install ==================== */
.install { background: var(--orange-bg); }
.steps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; position: relative; }
.step-card { text-align: center; }
.step-num {
    width: 50px; height: 50px; border-radius: 50%; background: var(--orange-gradient);
    color: #fff; font-size: 1.3rem; font-weight: 800; display: flex;
    align-items: center; justify-content: center; margin: 0 auto 16px;
    box-shadow: 0 4px 14px rgba(232,96,10,.3);
}
.step-card h3 { font-size: 1.05rem; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.step-card p { font-size: .88rem; color: var(--text-secondary); max-width: 260px; margin: 0 auto; }

/* ==================== CTA ==================== */
.cta {
    background: var(--orange-gradient); color: #fff;
    text-align: center; padding: 60px 20px;
}
.cta h2 { font-size: clamp(1.4rem, 4vw, 2rem); font-weight: 800; margin-bottom: 12px; }
.cta p { font-size: 1rem; opacity: .9; margin-bottom: 24px; max-width: 480px; margin-left: auto; margin-right: auto; }

/* ==================== Footer ==================== */
.footer {
    background: var(--text-primary); color: rgba(255,255,255,.6);
    padding: 40px 20px 24px; text-align: center; font-size: .9rem;
}
.footer-brand { font-size: 1.2rem; font-weight: 700; color: #fff; margin-bottom: 6px; }
.footer-brand img { width: 26px; height: 26px; vertical-align: middle; border-radius: 6px; object-fit: contain; margin-right: 6px; display: inline-block; }
.footer-brand span { color: var(--orange-light); }
.footer-tagline { color: rgba(255,255,255,.6); margin-bottom: 16px; font-size: .85rem; }
.footer-links { display: flex; justify-content: center; gap: 20px; margin-bottom: 16px; flex-wrap: wrap; }
.footer-links a { color: rgba(255,255,255,.6); font-size: .85rem; }
.footer-links a:hover { color: #fff; }
.footer-divider { border: none; border-top: 1px solid rgba(255,255,255,.1); margin: 16px 0; }
.footer-copy { font-size: .8rem; }

/* ==================== Responsive ==================== */
@media (max-width: 900px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .platform-grid { grid-template-columns: repeat(3, 1fr); }
    .arch-split { grid-template-columns: repeat(2, 1fr); }
    .arch-features { grid-template-columns: repeat(2, 1fr); }
    .skills-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-stats { gap: 24px; }
}
@media (max-width: 640px) {
    .nav-links {
        display: none; position: absolute; top: 60px; left: 0; right: 0;
        background: #fff; flex-direction: column; padding: 16px;
        border-bottom: 1px solid var(--gray-200); box-shadow: var(--shadow-md);
    }
    .nav-links.open { display: flex; }
    .nav-toggle { display: block; }
    .hero { padding: 110px 20px 40px; }
    .hero-actions { flex-direction: column; align-items: center; }
    .hero-actions .btn { width: 100%; max-width: 300px; justify-content: center; }
    .hero-stats { flex-direction: column; gap: 12px; align-items: center; }
    .features-grid { grid-template-columns: 1fr; }
    .platform-grid { grid-template-columns: repeat(3, 1fr); }
    .arch-split { grid-template-columns: repeat(2, 1fr); }
    .arch-features { grid-template-columns: 1fr; }
    .steps-grid { grid-template-columns: 1fr; gap: 20px; }
    .skills-grid { grid-template-columns: 1fr; }
    .download-group { flex-direction: column; align-items: center; gap: 8px; }
    .download-group .dl-btn { width: 100%; max-width: 280px; justify-content: center; font-size: .85rem; padding: 10px 18px; }
    .timeline-item { padding-left: 44px; }
    section { padding: 50px 0; }
}
@media (max-width: 400px) {
    .platform-grid { grid-template-columns: repeat(2, 1fr); }
    .arch-split { grid-template-columns: 1fr 1fr; }
}

/* ==================== Animations ==================== */
.fade-up { opacity: 0; transform: translateY(25px); transition: opacity .5s ease, transform .5s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }