/* Reset & Base */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { 
    font-family: 'Microsoft YaHei', 'Heiti SC', sans-serif; 
    /* Paper texture background */
    background-color: #f4f1ea; 
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.06'/%3E%3C/svg%3E");
    color: #1a1a1a; 
    line-height: 1.6; 
    min-height: 100vh; 
    overflow-x: hidden; 
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

/* Theme Variables - Screen Print */
:root {
    --bg-paper: #f4f1ea;
    --bg-paper-light: #faf8f5;
    --cyan: #00a8e8;
    --magenta: #ff3366;
    --dark: #1a1a1a;
    --offset-x: 4px;
    --offset-y: 4px;
}

/* Screen Print Text Effect */
.sp-text {
    color: var(--dark);
    text-shadow: 
        var(--offset-x) var(--offset-y) 0 rgba(0, 168, 232, 0.8), 
        calc(var(--offset-x) * -1) calc(var(--offset-y) * -1) 0 rgba(255, 51, 102, 0.8);
    mix-blend-mode: multiply;
    letter-spacing: 2px;
}

/* Navigation */
.navbar { 
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    padding: 20px 5%; 
    background: var(--bg-paper); 
    border-bottom: 4px solid var(--dark);
    position: sticky; 
    top: 0; 
    z-index: 100; 
}
.nav-logo { 
    font-size: 28px; 
    font-weight: 900; 
    display: flex;
    align-items: center;
    gap: 10px;
    text-transform: uppercase;
}
.nav-logo svg {
    width: 36px;
    height: 36px;
}
.nav-links { display: flex; gap: 30px; align-items: center; font-weight: 900; }
.nav-links a { 
    color: var(--dark); 
    transition: all 0.2s; 
    font-size: 16px; 
    text-transform: uppercase;
    position: relative;
}
.nav-links a:hover { 
    color: var(--magenta); 
    text-shadow: 2px 2px 0 var(--cyan);
}
.btn-download-nav { 
    padding: 10px 24px; 
    background: var(--magenta);
    color: var(--bg-paper) !important; 
    border: 3px solid var(--dark);
    box-shadow: 4px 4px 0 var(--cyan);
    transition: all 0.2s; 
}
.btn-download-nav:hover { 
    transform: translate(2px, 2px);
    box-shadow: 2px 2px 0 var(--cyan);
}

/* Hero Section */
.hero-wrapper {
    position: relative;
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 80px 5% 100px;
    overflow: hidden;
    border-bottom: 4px solid var(--dark);
    background: radial-gradient(circle at center, var(--bg-paper-light) 0%, var(--bg-paper) 100%);
}

/* Screen Print Halftone Background */
.halftone-bg {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background-image: radial-gradient(var(--dark) 15%, transparent 16%), radial-gradient(var(--dark) 15%, transparent 16%);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    opacity: 0.05;
    z-index: 1;
    pointer-events: none;
}

/* Overlapping Paper Planes */
.sp-planes-container {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 800px;
    height: 800px;
    z-index: 2;
    pointer-events: none;
    opacity: 0.15;
}
.sp-plane {
    position: absolute;
    width: 100%;
    height: 100%;
    mix-blend-mode: multiply;
}
.sp-plane-cyan {
    fill: var(--cyan);
    transform: translate(-20px, 20px) rotate(-10deg);
}
.sp-plane-magenta {
    fill: var(--magenta);
    transform: translate(20px, -20px) rotate(-5deg);
}

.hero-content { 
    z-index: 5; 
    max-width: 1000px; 
    text-align: center;
    position: relative;
}

.hero-title {
    font-size: 64px; 
    font-weight: 900;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero p { 
    font-size: 22px; 
    margin-bottom: 40px; 
    font-weight: bold;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    background: var(--bg-paper);
    padding: 10px;
    border: 3px solid var(--dark);
    box-shadow: 6px 6px 0 var(--cyan);
}

.hero-buttons { display: flex; gap: 25px; justify-content: center; margin-bottom: 60px; flex-wrap: wrap; }

.btn-sp { 
    padding: 18px 40px; 
    font-size: 20px; 
    font-weight: 900; 
    color: var(--bg-paper); 
    background: var(--dark);
    border: 3px solid var(--dark);
    box-shadow: 6px 6px 0 var(--magenta), -6px -6px 0 var(--cyan);
    transition: all 0.2s;
    text-transform: uppercase;
}
.btn-sp:hover { 
    transform: translate(2px, 2px);
    box-shadow: 4px 4px 0 var(--magenta), -4px -4px 0 var(--cyan);
}

.btn-sp-outline { 
    padding: 18px 40px; 
    font-size: 20px; 
    font-weight: 900; 
    color: var(--dark); 
    background: var(--bg-paper);
    border: 3px solid var(--dark);
    box-shadow: 6px 6px 0 var(--cyan), -6px -6px 0 var(--magenta);
    transition: all 0.2s;
}
.btn-sp-outline:hover { 
    transform: translate(2px, 2px);
    box-shadow: 4px 4px 0 var(--cyan), -4px -4px 0 var(--magenta);
}

.hero-images { 
    display: flex; 
    justify-content: center; 
    gap: 30px; 
    z-index: 5; 
    align-items: flex-end; 
}
.hero-images img { 
    max-width: 28%; 
    border: 4px solid var(--dark);
    background: var(--bg-paper);
    padding: 10px;
    box-shadow: 10px 10px 0 var(--magenta);
    transition: all 0.3s; 
    /* High contrast, slightly desaturated for print look */
    filter: contrast(1.2) saturate(0.8);
}
.hero-images img:nth-child(2) {
    box-shadow: 10px 10px 0 var(--cyan);
    transform: translateY(-20px);
}
.hero-images img:hover { 
    transform: translateY(-10px) scale(1.02); 
}

/* Features Section */
.features { padding: 100px 5%; background: var(--bg-paper-light); position: relative; z-index: 2; border-bottom: 4px solid var(--dark);}
.section-title { 
    text-align: center; 
    font-size: 42px; 
    margin-bottom: 70px; 
    font-weight: 900;
}

.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto; }

.feature-card { 
    padding: 40px 30px; 
    text-align: center; 
    background: var(--bg-paper);
    border: 3px solid var(--dark);
    box-shadow: 8px 8px 0 var(--cyan);
    transition: all 0.3s; 
    position: relative;
}
.feature-card:nth-child(even) {
    box-shadow: 8px 8px 0 var(--magenta);
}
.feature-card:hover { 
    transform: translate(-4px, -4px); 
    box-shadow: 12px 12px 0 var(--dark);
}
.feature-card h3 { 
    font-size: 24px; 
    margin-bottom: 15px; 
    font-weight: 900; 
    text-transform: uppercase;
    background: var(--dark);
    color: var(--bg-paper);
    display: inline-block;
    padding: 5px 15px;
    transform: rotate(-2deg);
}
.feature-card p { font-size: 16px; font-weight: bold;}

/* Blog Section */
.blog { padding: 100px 5%; background: var(--bg-paper); border-bottom: 4px solid var(--dark);}
.blog-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 50px; max-width: 1100px; margin: 0 auto; }
.blog-card { 
    display: flex; 
    flex-direction: column; 
    background: var(--bg-paper-light);
    border: 4px solid var(--dark);
    box-shadow: 10px 10px 0 var(--magenta);
    transition: all 0.3s;
}
.blog-card:nth-child(2) { box-shadow: 10px 10px 0 var(--cyan); }
.blog-card:hover { transform: translate(-5px, -5px); box-shadow: 15px 15px 0 var(--dark); }
.blog-card img { width: 100%; height: 280px; object-fit: cover; border-bottom: 4px solid var(--dark); filter: contrast(1.3) grayscale(0.2);}
.blog-content { padding: 35px; }
.blog-date { display: inline-block; margin-bottom: 15px; font-size: 14px; color: var(--bg-paper); background: var(--dark); padding: 5px 12px; font-weight: 900;}
.blog-content h3 { font-size: 24px; margin-bottom: 15px; font-weight: 900; }
.blog-content p { font-weight: bold; margin-bottom: 0; }
.btn-more { 
    display: block; 
    width: 260px; 
    margin: 70px auto 0; 
    text-align: center; 
    padding: 18px; 
    background: var(--bg-paper);
    color: var(--dark); 
    font-weight: 900; 
    font-size: 18px;
    border: 4px solid var(--dark);
    box-shadow: 6px 6px 0 var(--cyan);
    transition: all 0.3s; 
    text-transform: uppercase;
}
.btn-more:hover { background: var(--dark); color: var(--bg-paper); box-shadow: 6px 6px 0 var(--magenta); }

/* FAQ Section */
.faq { padding: 100px 5%; max-width: 900px; margin: 0 auto; background: var(--bg-paper-light); margin-top: 50px; margin-bottom: 80px; border: 4px solid var(--dark); box-shadow: 15px 15px 0 var(--cyan);}
.faq-item { 
    background: var(--bg-paper); 
    margin-bottom: 25px; 
    padding: 30px; 
    border: 3px solid var(--dark);
    box-shadow: 5px 5px 0 var(--magenta);
    transition: all 0.3s;
}
.faq-item:nth-child(even) { box-shadow: 5px 5px 0 var(--cyan); }
.faq-item:hover { transform: translateX(-5px); box-shadow: 10px 10px 0 var(--dark); }
.faq-question { font-size: 20px; font-weight: 900; margin-bottom: 15px; }
.faq-question::before { content: 'Q: '; color: var(--magenta); font-size: 24px;}
.faq-answer { font-weight: bold; font-size: 16px; }

/* Footer */
.footer { background: var(--dark); padding: 80px 5% 30px; color: var(--bg-paper); }
.footer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto 50px; }
.footer-col h4 { font-size: 20px; color: var(--cyan); margin-bottom: 25px; font-weight: 900; text-transform: uppercase;}
.footer-col ul li { margin-bottom: 15px; }
.footer-col ul li a { color: var(--bg-paper); transition: color 0.2s; font-weight: bold;}
.footer-col ul li a:hover { color: var(--magenta); }
.footer-bottom { text-align: center; padding-top: 30px; border-top: 2px dashed rgba(255,255,255,0.2); font-size: 14px; font-weight: bold; color: #888;}

/* Download Page Grid */
.download-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 40px; max-width: 1100px; margin: 80px auto; padding: 0 5%; }
.download-card { 
    padding: 50px 30px; 
    text-align: center; 
    background: var(--bg-paper-light); 
    border: 4px solid var(--dark);
    box-shadow: 10px 10px 0 var(--cyan);
    transition: all 0.3s;
}
.download-card:nth-child(even) { box-shadow: 10px 10px 0 var(--magenta); }
.download-card:hover { transform: translate(-5px, -5px); box-shadow: 15px 15px 0 var(--dark); }
.download-card h3 { font-size: 26px; margin-bottom: 20px; font-weight: 900; }
.download-card p { font-weight: bold; margin-bottom: 35px; font-size: 16px; }
.btn-dl-card { 
    display: inline-block; 
    padding: 15px 30px; 
    background: var(--dark);
    color: var(--bg-paper); 
    font-weight: 900; 
    border: 3px solid var(--dark);
    box-shadow: 5px 5px 0 var(--magenta);
    transition: all 0.3s; 
    text-transform: uppercase;
}
.btn-dl-card:hover { background: var(--bg-paper); color: var(--dark); box-shadow: 5px 5px 0 var(--cyan); }

/* Page specific headers */
.page-header { 
    padding: 120px 5% 100px; 
    text-align: center; 
    position: relative;
    background: var(--bg-paper);
    border-bottom: 4px solid var(--dark);
    overflow: hidden;
}
.page-header-content {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
    background: var(--bg-paper-light);
    padding: 50px;
    border: 4px solid var(--dark);
    box-shadow: 12px 12px 0 var(--cyan);
}
.page-header h1 { 
    font-size: 52px; 
    margin-bottom: 20px; 
    font-weight: 900;
}
.page-header p { font-size: 20px; font-weight: bold;}

/* === perf: reduce motion & lower GPU cost === */
.feature-card,
.blog-card,
.hero-content,
.glass-panel,
.pearl-card {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
}
.navbar {
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation: none !important;
        transition: none !important;
        scroll-behavior: auto !important;
    }
}

/* perf: limit decorative infinite layers on mid/low-end devices */
@media (max-width: 768px) {
    .bubble:nth-child(n+3),
    .tiny-plane:nth-child(n+3),
    .bg-shard:nth-child(n+4),
    .orb:nth-child(n+2) {
        display: none !important;
    }
}