/* ===== Design tokens ===== */
:root {
    --brand-purple:#837fd9;    /* primary brand color */
    --brand-dark:#0f172a;      /* headings / footer */
    --text:#0b1324;
    --muted:#64748b;
    --bg:#f8fafc;
    --card:#ffffff;
    --border:#e2e8f0;
    --radius:16px;
}

/* Base */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
}
a { color: var(--brand-purple); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 20px; }

/* Buttons */
.btn { display: inline-block; padding: 10px 16px; border-radius: 10px; font-weight: 600;}
.btn-primary { background: var(--brand-purple); color: #fff; }
.btn-primary:hover { opacity: .9; text-decoration: none; }
.btn-outline { border: 1px solid var(--border); color: var(--text); background: #fff; }
.btn-outline:hover { border-color: #cbd5e1; text-decoration: none; }
.btn-row { display:flex; gap:12px; flex-wrap:wrap; margin-top:18px; }

/* Sections & typography */
section { padding: 72px 0; }
h1 { font-size: clamp(28px, 4vw, 44px); margin: 0 0 10px; color: var(--brand-dark); }
h2 { font-size: clamp(22px, 3vw, 32px); margin: 0 0 8px; color: var(--brand-dark); }
p.lead { color: #475569; font-size: 18px; line-height: 1.6; margin: 0; }
.muted { color: var(--muted); }
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; color: #5e59a6; }
.facts { margin: 12px 0 0 18px; line-height: 1.6; }
.bullet { margin: 0 0 0 18px; line-height: 1.6; }
.card-title { margin: 14px 0 6px;}


/* Grid helpers */
.grid { display: grid; gap: 20px; }
@media (min-width: 900px) {
    .grid-2 { grid-template-columns: 1.15fr .85fr; }
    .grid-3 { grid-template-columns: repeat(3, 1fr); }
}

/* Nav */
.nav {
    position: sticky; top: 0; z-index: 50;
    backdrop-filter: saturate(180%) blur(8px);
    background: rgba(255,255,255,.8);
    border-bottom: 1px solid var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; padding: 10px 0; }
.brand {
    display: flex; align-items: center; gap: 10px;
    font-weight: 700; letter-spacing: .2px; color: var(--brand-dark);
}
.logo {
    height: 40px;
    width: auto;
    display: block;
}
.nav a { color: #334155; margin-left: 18px; }

/* Hero */
.hero { padding: 96px 0 72px; }
.badge {
    display: inline-block; background: #a8a4e68e; color: #5e59a6;
    padding: 6px 10px; border-radius: 999px; font-weight: 600; font-size: 13px;
}

/* Media box */
.ratio {
    position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden;
    border-radius: var(--radius); border:1px solid var(--border); background:#e2e8f0;
}
.ratio iframe, .ratio video, .ratio img {
    position: absolute; inset: 0; width: 100%; height: 100%; border: 0; object-fit: cover;
}

/* Products band */
.products-band {
    background: #fff; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border);
}
.products-grid { margin-top: 18px; }
.footnote { margin-top: 14px; }

/* Why */
.why-grid {
    margin-top: 14px;
    display: grid;
    gap: 20px;
}
@media(min-width:900px) {
    .why-grid {
        grid-template-columns: repeat(2, 1fr); /* 2 列布局 */
    }
}

/* Contact */
.contact-band { background: #eef8ff; }

/* ===== Copy modal for email===== */
.modal { 
    position: fixed; inset: 0; display: none; 
}
.modal.is-visible { display: block; }
.modal__overlay {
    position: absolute; inset: 0;
    background: rgba(0,0,0,.35);
    backdrop-filter: blur(2px);
}
.modal__card {
    position: absolute; left: 50%; top: 50%;
    transform: translate(-50%, -50%) scale(.96);
    background: #fff; color: var(--brand-dark);
    border: 1px solid var(--border); border-radius: 14px;
    width: min(420px, 90vw); padding: 18px 20px;
    box-shadow: 0 12px 30px rgba(0,0,0,.18);
    opacity: 0; transition: opacity .18s ease, transform .18s ease;
}
.modal.is-visible .modal__card {
    opacity: 1; transform: translate(-50%, -50%) scale(1);
}
.modal__title { 
    color: #5e59a6;               /* your purple for title */
    font-weight: 700; margin-bottom: 6px;
}
.modal__text { color: var(--muted); }

/* Footer */
footer { background: var(--brand-dark); color: #cbd5e1; padding: 28px 0; }
footer a { color: #e2e8f0; }
.footer-inner {
    display:flex; align-items:center; justify-content:space-between; gap:12px; flex-wrap:wrap;
}