:root {
    --bg-main: #ffffff;
    --text-primary: #1c1e21;
    --text-secondary: #606770;
    --border-line: #dadde1;
    --btn-primary: #1877f2;
    --btn-primary-hover: #166fe5;
    --btn-secondary: #e4e6eb;
    --btn-secondary-hover: #d8dadf;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
}
* { margin: 0; padding: 0; box-sizing: border-box; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
body { background: var(--bg-main); color: var(--text-primary); line-height: 1.6; }
a { text-decoration: none; color: inherit; transition: 0.2s; }

/* Minimalist Nav */
.nav { border-bottom: 1px solid var(--border-line); position: sticky; top: 0; background: var(--bg-main); z-index: 100; display: flex; justify-content: space-between; align-items: center; padding: 15px 5%; height: 60px; }
.nav-brand { font-size: 22px; font-weight: 700; color: var(--text-primary); letter-spacing: -0.5px; }
.nav-links { display: flex; gap: 24px; align-items: center; }
.nav-links a { font-size: 14px; font-weight: 600; color: var(--text-secondary); }
.nav-links a:hover, .nav-links a.active { color: var(--text-primary); }
.nav-btn { background: var(--btn-primary); color: white !important; padding: 6px 16px; border-radius: 6px; }
.nav-btn:hover { background: var(--btn-primary-hover); }

/* Product Hero */
.hero { display: flex; flex-direction: column; align-items: center; text-align: center; padding: 80px 20px 60px; max-width: 800px; margin: 0 auto; }
.hero-label { font-size: 12px; font-weight: 700; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1.5px; margin-bottom: 15px; }
.hero h1 { font-size: 46px; font-weight: 800; line-height: 1.2; margin-bottom: 20px; letter-spacing: -1px; }
.hero p { font-size: 18px; color: var(--text-secondary); margin-bottom: 40px; font-weight: 400; }
.btn-group { display: flex; gap: 15px; justify-content: center; flex-wrap: wrap; }
.btn { padding: 12px 28px; border-radius: 6px; font-size: 15px; font-weight: 600; cursor: pointer; border: none; }
.btn-primary { background: var(--btn-primary); color: white; }
.btn-primary:hover { background: var(--btn-primary-hover); }
.btn-secondary { background: var(--btn-secondary); color: var(--text-primary); }
.btn-secondary:hover { background: var(--btn-secondary-hover); }

/* Clean Stats */
.stats { display: flex; justify-content: center; gap: 60px; padding: 40px 20px; border-top: 1px solid var(--border-line); border-bottom: 1px solid var(--border-line); flex-wrap: wrap; }
.stat-box { text-align: center; }
.stat-box h3 { font-size: 28px; font-weight: 700; margin-bottom: 5px; color: var(--text-primary); }
.stat-box p { font-size: 13px; color: var(--text-secondary); font-weight: 500; }

/* Container */
.container { max-width: 1000px; margin: 0 auto; padding: 80px 20px; }
.section-header { text-align: center; margin-bottom: 50px; }
.section-header h2 { font-size: 32px; font-weight: 700; margin-bottom: 15px; letter-spacing: -0.5px; }
.section-header p { font-size: 16px; color: var(--text-secondary); max-width: 600px; margin: 0 auto; }

/* Feature Grid (Clean Product Style) */
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 40px; margin-bottom: 80px; }
.feature-item { padding: 0; }
.feature-icon { width: 48px; height: 48px; background: #e7f3ff; color: var(--btn-primary); border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 20px; font-weight: bold; margin-bottom: 20px; }
.feature-item h3 { font-size: 20px; font-weight: 600; margin-bottom: 10px; color: var(--text-primary); }
.feature-item p { font-size: 15px; color: var(--text-secondary); line-height: 1.6; }

/* Product Image */
.product-img { width: 100%; border-radius: 12px; border: 1px solid var(--border-line); box-shadow: var(--shadow-md); margin-bottom: 80px; display: block; }

/* Guide & FAQ Accordion Style */
.accordion { max-width: 800px; margin: 0 auto 80px; border-top: 1px solid var(--border-line); }
.acc-item { border-bottom: 1px solid var(--border-line); padding: 25px 0; }
.acc-header { display: flex; align-items: center; gap: 15px; margin-bottom: 10px; }
.acc-num { color: var(--btn-primary); font-weight: 700; font-size: 16px; }
.acc-title { font-size: 18px; font-weight: 600; color: var(--text-primary); }
.acc-content { font-size: 15px; color: var(--text-secondary); padding-left: 35px; line-height: 1.6; }

/* Simple Footer */
.footer { padding: 40px 20px; text-align: center; border-top: 1px solid var(--border-line); }
.footer-links { display: flex; justify-content: center; gap: 25px; margin-bottom: 20px; flex-wrap: wrap; }
.footer-links a { color: var(--text-secondary); font-size: 14px; font-weight: 500; }
.footer-links a:hover { color: var(--text-primary); text-decoration: underline; }
.footer p { color: #8a8d91; font-size: 13px; }