/* ========== Reset & Base ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
    --primary: #4f46e5;
    --primary-light: #6366f1;
    --primary-dark: #3730a3;
    --accent: #06b6d4;
    --accent-light: #22d3ee;
    --bg: #f8fafc;
    --bg-card: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 4px 24px rgba(79,70,229,0.10);
    --shadow-hover: 0 12px 40px rgba(79,70,229,0.18);
    --radius: 16px;
    --radius-sm: 10px;
}
html { scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    min-height: 100vh;
}

/* ========== Header / Nav ========== */
.header {
    position: fixed; top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    transition: box-shadow .3s;
}
.header.scrolled { box-shadow: 0 2px 20px rgba(0,0,0,0.08); }
.nav-inner {
    max-width: 1200px; margin: 0 auto;
    padding: 0 24px; height: 64px;
    display: flex; align-items: center; justify-content: space-between;
}
.logo {
    font-size: 20px; font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
    text-decoration: none;
}
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a {
    text-decoration: none; color: var(--text-muted);
    font-size: 14px; font-weight: 500;
    transition: color .2s;
}
.nav-links a:hover,
.nav-links a:focus-visible { color: var(--primary); }

/* ========== Hero ========== */
.hero {
    padding: 140px 24px 80px;
    text-align: center;
    background: linear-gradient(160deg, #eef2ff 0%, #ecfeff 50%, #f0fdf4 100%);
    position: relative; overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute; top: -200px; right: -200px;
    width: 600px; height: 600px;
    background: radial-gradient(circle, rgba(99,102,241,0.12) 0%, transparent 70%);
    pointer-events: none;
}
.hero::after {
    content: '';
    position: absolute; bottom: -150px; left: -150px;
    width: 450px; height: 450px;
    background: radial-gradient(circle, rgba(6,182,212,0.10) 0%, transparent 70%);
    pointer-events: none;
}
.hero-badge {
    display: inline-block;
    padding: 6px 18px; border-radius: 100px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: #fff; font-size: 13px; font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: 0.5px;
}
.hero h1 {
    font-size: clamp(32px, 5vw, 52px);
    font-weight: 900; line-height: 1.2;
    letter-spacing: -1px;
    margin-bottom: 18px;
    position: relative;
}
.hero h1 span {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero p {
    max-width: 600px; margin: 0 auto 36px;
    font-size: 17px; color: var(--text-muted);
    position: relative;
}
.hero-stats {
    display: flex; justify-content: center; gap: 48px;
    flex-wrap: wrap; position: relative;
}
.stat-item { text-align: center; }
.stat-num {
    font-size: 24px; font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}
.stat-label { font-size: 13px; color: var(--text-muted); margin-top: 2px; }

/* ========== Section Common ========== */
.section { padding: 80px 24px; }
.section-inner { max-width: 1200px; margin: 0 auto; }
.section-title {
    text-align: center; margin-bottom: 56px;
}
.section-title h2 {
    font-size: clamp(26px, 3.5vw, 36px); font-weight: 800;
    letter-spacing: -0.5px; margin-bottom: 12px;
}
.section-title p { font-size: 16px; color: var(--text-muted); }

/* ========== Software Grid ========== */
.software-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 28px;
}
.soft-card {
    background: var(--bg-card);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow: hidden;
    transition: transform .35s ease, box-shadow .35s ease;
    opacity: 0; transform: translateY(30px);
}
.soft-card.visible {
    opacity: 1; transform: translateY(0);
}
.soft-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}
.card-header {
    padding: 28px 28px 0;
    display: flex; align-items: flex-start; gap: 16px;
}
.card-icon {
    width: 56px; height: 56px; border-radius: 14px;
    display: flex; align-items: center; justify-content: center;
    font-size: 26px; flex-shrink: 0;
}
.card-icon.icon-1  { background: linear-gradient(135deg, #6366f1, #8b5cf6); }
.card-icon.icon-2  { background: linear-gradient(135deg, #ef4444, #f97316); }
.card-icon.icon-3  { background: linear-gradient(135deg, #ec4899, #f43f5e); }
.card-icon.icon-4  { background: linear-gradient(135deg, #14b8a6, #22d3ee); }
.card-icon.icon-5  { background: linear-gradient(135deg, #f59e0b, #eab308); }
.card-icon.icon-6  { background: linear-gradient(135deg, #3b82f6, #06b6d4); }
.card-icon.icon-7  { background: linear-gradient(135deg, #10b981, #34d399); }
.card-icon.icon-8  { background: linear-gradient(135deg, #8b5cf6, #a78bfa); }
.card-info h3 {
    font-size: 18px; font-weight: 700; margin-bottom: 4px;
}
.card-tag {
    display: inline-block;
    padding: 2px 10px; border-radius: 100px;
    font-size: 11px; font-weight: 600;
    letter-spacing: 0.3px;
}
.tag-online {
    background: #ecfdf5; color: #059669;
}
.tag-download {
    background: #eff6ff; color: #2563eb;
}
.card-body {
    padding: 16px 28px 24px;
}
.card-desc {
    font-size: 14px; color: var(--text-muted);
    line-height: 1.8;
    display: -webkit-box;
    -webkit-line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.card-actions {
    padding: 0 28px 28px;
    display: flex; gap: 12px;
}
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    padding: 10px 22px; border-radius: var(--radius-sm);
    font-size: 14px; font-weight: 600;
    text-decoration: none; cursor: pointer;
    border: none; transition: all .25s ease;
    flex: 1;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff; box-shadow: 0 2px 12px rgba(79,70,229,0.30);
}
.btn-primary:hover,
.btn-primary:focus-visible {
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(79,70,229,0.40);
}
.btn-accent {
    background: linear-gradient(135deg, var(--accent), var(--accent-light));
    color: #fff; box-shadow: 0 2px 12px rgba(6,182,212,0.30);
}
.btn-accent:hover,
.btn-accent:focus-visible {
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(6,182,212,0.40);
}
.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 1.5px solid var(--primary);
}
.btn-outline:hover {
    background: var(--primary); color: #fff;
}
.btn svg { width: 16px; height: 16px; fill: currentColor; flex-shrink: 0; }

/* ========== Features Bar ========== */
.features-bar {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary), var(--accent));
    padding: 48px 24px;
    color: #fff;
}
.features-inner {
    max-width: 1200px; margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 32px; text-align: center;
}
.feat-item .feat-icon { font-size: 36px; margin-bottom: 12px; }
.feat-item h4 { font-size: 16px; font-weight: 700; margin-bottom: 6px; }
.feat-item p { font-size: 13px; opacity: 0.85; }

/* ========== Footer ========== */
.footer {
    background: #0f172a; color: #94a3b8;
    padding: 48px 24px 32px; text-align: center;
}
.footer-inner { max-width: 1200px; margin: 0 auto; }
.footer-logo {
    font-size: 22px; font-weight: 800; color: #fff;
    margin-bottom: 12px;
}
.footer p { font-size: 13px; line-height: 1.8; }
.footer a { color: var(--accent-light); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* ========== Responsive ========== */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .hero { padding: 120px 20px 60px; }
    .hero-stats { gap: 28px; }
    .stat-num { font-size: 26px; }
    .software-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    .section { padding: 56px 16px; }
    .features-bar { padding: 36px 16px; }
    .card-header { padding: 22px 20px 0; }
    .card-body { padding: 12px 20px 18px; }
    .card-actions { padding: 0 20px 22px; flex-direction: column; }
}

/* ========== Scroll Animation ========== */
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(30px); }
    to   { opacity: 1; transform: translateY(0); }
}
.soft-card.visible { animation: fadeUp .5s ease forwards; }
.soft-card:nth-child(1).visible { animation-delay: 0s; }
.soft-card:nth-child(2).visible { animation-delay: .08s; }
.soft-card:nth-child(3).visible { animation-delay: .16s; }
.soft-card:nth-child(4).visible { animation-delay: .24s; }
.soft-card:nth-child(5).visible { animation-delay: .32s; }
.soft-card:nth-child(6).visible { animation-delay: .40s; }
.soft-card:nth-child(7).visible { animation-delay: .48s; }
.soft-card:nth-child(8).visible { animation-delay: .56s; }