/* ============================================================
   Zenbox — Marketing site design system
   Font: Be Vietnam Pro · Icons: Bootstrap Icons · Brand: indigo→blue
   ============================================================ */
:root {
    --zb-indigo: #4f46e5;
    --zb-blue:   #2563eb;
    --zb-grad:   linear-gradient(135deg, #4f46e5 0%, #2563eb 100%);
    --zb-ink:    #0f172a;
    --zb-body:   #475569;
    --zb-muted:  #94a3b8;
    --zb-line:   #e2e8f0;
    --zb-bg:     #ffffff;
    --zb-soft:   #f8fafc;
    --zb-soft2:  #f1f5f9;
    --zb-radius: 14px;
    --zb-shadow: 0 10px 30px rgba(15,23,42,.08);
    --zb-shadow-sm: 0 2px 10px rgba(15,23,42,.06);
}

* { box-sizing: border-box; }
body.zb {
    margin: 0;
    font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Arial, sans-serif;
    color: var(--zb-body);
    background: var(--zb-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
.zb a { color: var(--zb-blue); text-decoration: none; }
.zb h1, .zb h2, .zb h3, .zb h4 { color: var(--zb-ink); line-height: 1.25; margin: 0 0 .5em; font-weight: 700; }
.zb h1 { font-size: 44px; letter-spacing: -.02em; }
.zb h2 { font-size: 32px; letter-spacing: -.01em; }
.zb h3 { font-size: 20px; }
.zb p  { margin: 0 0 1em; }
.zb-container { max-width: 1140px; margin: 0 auto; padding: 0 20px; }
.zb-section { padding: 80px 0; }
.zb-center { text-align: center; }
.zb-eyebrow { display: inline-block; font-size: 13px; font-weight: 600; color: var(--zb-indigo);
    background: #eef2ff; padding: 6px 14px; border-radius: 999px; margin-bottom: 16px; }
.zb-lead { font-size: 18px; color: var(--zb-body); max-width: 640px; margin: 0 auto 28px; }
/* Lead trong khối căn giữa: ép tường minh (không dựa thừa kế) — tránh lệch trái khi có style chen ngang */
.zb-center .zb-lead { text-align: center; margin-left: auto; margin-right: auto; }
.zb-muted { color: var(--zb-muted); }

/* ---- Buttons ---- */
.zb-btn { position: relative; overflow: hidden; display: inline-flex; align-items: center; gap: 8px; font-weight: 600; font-size: 15px;
    padding: 12px 22px; border-radius: 10px; border: 1px solid transparent; cursor: pointer;
    transition: transform .18s cubic-bezier(.2,.7,.3,1), box-shadow .18s, background .18s; text-decoration: none; }
.zb-btn > * { position: relative; z-index: 1; }   /* chữ/icon nằm trên vệt sáng */
/* Vệt sáng lướt qua khi hover (kiểu CTA cao cấp) */
.zb-btn::before { content: ""; position: absolute; top: 0; left: -120%; width: 60%; height: 100%; z-index: 0;
    background: linear-gradient(100deg, transparent, rgba(255,255,255,.45), transparent);
    transform: skewX(-18deg); transition: left .55s ease; }
.zb-btn:hover::before { left: 130%; }
.zb-btn:hover { transform: translateY(-2px); }
.zb-btn:active { transform: translateY(0); }
.zb-btn-primary { background: var(--zb-grad); color: #fff; box-shadow: 0 6px 18px rgba(79,70,229,.32); }
.zb-btn-primary:hover { color: #fff; box-shadow: 0 12px 30px rgba(79,70,229,.5); }
.zb-btn-ghost::before { background: linear-gradient(100deg, transparent, rgba(37,99,235,.12), transparent); }
.zb-btn-ghost { background: #fff; color: var(--zb-ink); border-color: var(--zb-line); }
.zb-btn-ghost:hover { border-color: var(--zb-blue); color: var(--zb-blue); }
.zb-btn-light { background: rgba(255,255,255,.15); color: #fff; border-color: rgba(255,255,255,.35); }
.zb-btn-light:hover { background: rgba(255,255,255,.25); color: #fff; }
.zb-btn-lg { padding: 15px 30px; font-size: 16px; }
/* Fix: nút dạng <a> bị '.zb a {color:blue}' đè → ép đúng màu chữ (specificity cao hơn) */
.zb a.zb-btn-primary, .zb a.zb-btn-primary:hover,
.zb a.zb-btn-light, .zb a.zb-btn-light:hover { color: #fff; }
.zb a.zb-btn-ghost { color: var(--zb-ink); }
.zb a.zb-btn-ghost:hover { color: var(--zb-blue); }

/* ---- Navbar ---- */
.zb-nav { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.85);
    backdrop-filter: saturate(180%) blur(12px); border-bottom: 1px solid transparent; transition: border-color .2s, box-shadow .2s; }
.zb-nav.scrolled { border-bottom-color: var(--zb-line); box-shadow: var(--zb-shadow-sm); }
.zb-nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.zb-brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: var(--zb-ink); letter-spacing: -.02em; }
.zb-brand .zb-logo { width: 34px; height: 34px; border-radius: 9px; background: var(--zb-grad); color: #fff;
    display: grid; place-items: center; font-size: 18px; }
/* Logo ZENBOX dạng ảnh (thay icon font) — ảnh đã có nền bo góc sẵn */
.zb-brand .zb-logo-img { width: 34px; height: 34px; border-radius: 9px; object-fit: contain; vertical-align: middle; }
.zb-nav-menu { display: flex; align-items: center; gap: 28px; flex: 1; justify-content: space-between; margin-left: 48px; }
.zb-nav-links { display: flex; align-items: center; gap: 28px; }
.zb-nav-links a { color: var(--zb-body); font-weight: 500; font-size: 15px; }
.zb-nav-links a:hover { color: var(--zb-ink); }
.zb-nav-cta { display: flex; align-items: center; gap: 12px; }
.zb-burger { display: none; background: none; border: none; font-size: 26px; line-height: 1; color: var(--zb-ink);
    cursor: pointer; width: 44px; height: 44px; border-radius: 10px; align-items: center; justify-content: center; transition: background .15s; }
.zb-burger:hover { background: rgba(79,70,229,.08); }
.zb-burger[aria-expanded="true"] { background: rgba(79,70,229,.10); color: var(--zb-indigo); }

/* ---- Hero ---- */
.zb-hero { position: relative; background: radial-gradient(1200px 480px at 50% -10%, #eef2ff 0%, #fff 60%); padding: 70px 0 60px; overflow: hidden; }
.zb-hero h1 span { background: var(--zb-grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.zb-hero-cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin-top: 8px; }
.zb-trust { margin-top: 26px; font-size: 14px; color: var(--zb-muted); display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; }
.zb-trust i { color: #22c55e; }
.zb-hero-shot { margin: 44px auto 0; max-width: 920px; background: #fff; border: 1px solid var(--zb-line);
    border-radius: 18px; box-shadow: var(--zb-shadow); overflow: hidden; }
.zb-hero-shot .bar { display: flex; gap: 7px; padding: 12px 16px; border-bottom: 1px solid var(--zb-line); }
.zb-hero-shot .bar span { width: 11px; height: 11px; border-radius: 50%; background: #e2e8f0; }
.zb-hero-shot .body { display: grid; grid-template-columns: 200px 1fr; min-height: 260px; }
.zb-hero-shot .side { background: var(--zb-soft); border-right: 1px solid var(--zb-line); padding: 16px; }
.zb-hero-shot .side .row { height: 12px; background: #e7ecf3; border-radius: 6px; margin-bottom: 12px; }
.zb-hero-shot .side .row.short { width: 60%; }
.zb-hero-shot .main { padding: 18px; }
.zb-hero-shot .bub { max-width: 70%; padding: 10px 14px; border-radius: 12px; margin-bottom: 10px; font-size: 13px; }
.zb-hero-shot .bub.in { background: var(--zb-soft2); color: var(--zb-ink); }
.zb-hero-shot .bub.out { background: var(--zb-grad); color: #fff; margin-left: auto; }
.zb-hero-shot .bub.ai { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }

/* ---- Split 2-cột (spotlight tính năng) ---- */
.zb-split { display: grid; grid-template-columns: 1fr 1fr; gap: 44px; align-items: center; }
@media (max-width: 860px) {
    .zb-split { grid-template-columns: 1fr; gap: 24px; }
    .zb-split > * { order: 0 !important; }
}

/* ---- Feature cards ---- */
.zb-grid { display: grid; gap: 20px; }
.zb-grid-3 { grid-template-columns: repeat(3, 1fr); }
.zb-grid-4 { grid-template-columns: repeat(4, 1fr); }
.zb-card { background: #fff; border: 1px solid var(--zb-line); border-radius: var(--zb-radius); padding: 26px; transition: transform .15s, box-shadow .15s; }
.zb-card:hover { transform: translateY(-3px); box-shadow: var(--zb-shadow); }
.zb-ico { width: 50px; height: 50px; border-radius: 12px; background: #eef2ff; color: var(--zb-indigo);
    display: grid; place-items: center; font-size: 24px; margin-bottom: 16px; }
.zb-card h3 { margin-bottom: 8px; }
.zb-card p { font-size: 14.5px; margin: 0; }

/* ---- Pricing ---- */
.zb-price-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; align-items: stretch; }
.zb-plan { display: flex; flex-direction: column; background: #fff; border: 1px solid var(--zb-line);
    border-radius: var(--zb-radius); padding: 26px 22px; position: relative; }
.zb-plan.popular { border: 2px solid var(--zb-indigo); box-shadow: var(--zb-shadow); }
.zb-plan .tag-pop { position: absolute; top: -13px; left: 50%; transform: translateX(-50%);
    background: var(--zb-grad); color: #fff; font-size: 12px; font-weight: 600; padding: 5px 14px; border-radius: 999px; }
.zb-plan h3 { margin-bottom: 2px; }
.zb-plan .sub { font-size: 13px; color: var(--zb-muted); min-height: 34px; }
.zb-plan .price { font-size: 34px; font-weight: 800; color: var(--zb-ink); margin: 10px 0 2px; }
.zb-plan .price small { font-size: 14px; font-weight: 500; color: var(--zb-muted); }
.zb-plan ul { list-style: none; padding: 0; margin: 18px 0 22px; flex: 1; }
.zb-plan li { font-size: 14px; padding: 7px 0; display: flex; align-items: flex-start; gap: 9px; }
.zb-plan li i.on { color: #22c55e; }
.zb-plan li i.off { color: #cbd5e1; }
.zb-plan li.off span { color: var(--zb-muted); }

/* ---- FAQ ---- */
.zb-faq { max-width: 800px; margin: 0 auto; }
.zb-faq-item { border: 1px solid var(--zb-line); border-radius: 12px; margin-bottom: 12px; background: #fff; overflow: hidden; }
.zb-faq-q { width: 100%; text-align: left; background: none; border: none; padding: 18px 20px; font-size: 16px;
    font-weight: 600; color: var(--zb-ink); cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 12px; font-family: inherit; }
.zb-faq-q i { transition: transform .2s; color: var(--zb-indigo); }
.zb-faq-item.open .zb-faq-q i { transform: rotate(180deg); }
.zb-faq-a { max-height: 0; overflow: hidden; transition: max-height .25s ease; }
.zb-faq-a-inner { padding: 0 20px 18px; font-size: 15px; color: var(--zb-body); }
.zb-faq-item.open .zb-faq-a { max-height: 320px; }

/* ---- CTA band ---- */
.zb-cta { background: var(--zb-grad); border-radius: 22px; padding: 54px 40px; text-align: center; color: #fff; }
.zb-cta h2 { color: #fff; }
.zb-cta p { color: rgba(255,255,255,.9); max-width: 560px; margin: 0 auto 24px; }

/* ---- Footer ---- */
.zb-footer { background: var(--zb-ink); color: #cbd5e1; padding: 56px 0 28px; margin-top: 0; }
.zb-footer a { color: #cbd5e1; }
.zb-footer a:hover { color: #fff; }
.zb-footer h4 { color: #fff; font-size: 15px; margin-bottom: 14px; }
.zb-foot-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 30px; }
.zb-foot-grid ul { list-style: none; padding: 0; margin: 0; }
.zb-foot-grid li { margin-bottom: 10px; font-size: 14px; }
.zb-foot-grid li .bi { width: 18px; color: #64748b; }
.zb-foot-channels { display: flex; gap: 10px; margin-top: 16px; }
.zb-foot-channels span { display: inline-flex; align-items: center; justify-content: center; width: 34px; height: 34px; border-radius: 50%; color: #fff; font-size: 17px; transition: transform .15s; }
.zb-foot-channels span:hover { transform: translateY(-2px); }
.zb-foot-channels span b { font-family: Arial, Helvetica, sans-serif; font-weight: 800; font-size: 18px; line-height: 1; }
.zb-foot-bottom { border-top: 1px solid #1e293b; margin-top: 36px; padding-top: 20px; font-size: 13px; color: var(--zb-muted);
    display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }

/* ---- Forms (contact / trial) ---- */
.zb-form { max-width: 560px; margin: 0 auto; background: #fff; border: 1px solid var(--zb-line); border-radius: var(--zb-radius); padding: 30px; box-shadow: var(--zb-shadow-sm); }
.zb-field { margin-bottom: 16px; }
.zb-field label { display: block; font-size: 14px; font-weight: 600; color: var(--zb-ink); margin-bottom: 6px; }
.zb-field input, .zb-field select, .zb-field textarea { width: 100%; padding: 12px 14px; font-size: 15px;
    border: 1px solid var(--zb-line); border-radius: 10px; font-family: inherit; color: var(--zb-ink); background: #fff; }
.zb-field input:focus, .zb-field select:focus, .zb-field textarea:focus { outline: none; border-color: var(--zb-blue); box-shadow: 0 0 0 3px rgba(37,99,235,.15); }

.zb-alert { padding: 12px 16px; border-radius: 10px; font-size: 14px; margin-bottom: 16px; }
.zb-alert.ok { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }
.zb-alert.err { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }

/* ---- Responsive ---- */
@media (max-width: 920px) {
    .zb-grid-3, .zb-grid-4 { grid-template-columns: repeat(2, 1fr); }
    .zb-price-grid { grid-template-columns: repeat(2, 1fr); }
    .zb-foot-grid { grid-template-columns: 1fr 1fr; }
    .zb-hero-shot .body { grid-template-columns: 1fr; }
    .zb-hero-shot .side { display: none; }
}
@media (max-width: 680px) {
    .zb h1 { font-size: 33px; }
    .zb h2 { font-size: 26px; }
    .zb-section { padding: 56px 0; }
    .zb-grid-3, .zb-grid-4, .zb-price-grid, .zb-foot-grid { grid-template-columns: 1fr; }
}

/* ---- Mobile/tablet nav: gom links + CTA vào menu burger ---- */
@media (max-width: 820px) {
    .zb-burger { display: inline-flex; }
    /* Menu thả xuống full-width, panel riêng — không chen chúc trên thanh header */
    .zb-nav-menu {
        display: none;
        position: absolute; top: 68px; left: 0; right: 0;
        flex-direction: column; align-items: stretch; gap: 0;
        background: #fff; border-bottom: 1px solid var(--zb-line);
        box-shadow: var(--zb-shadow); padding: 8px 16px 18px;
        max-height: calc(100vh - 68px); overflow-y: auto;
    }
    .zb-nav-menu.open { display: flex; animation: zbMenuIn .18s ease-out; }
    /* Links: dạng list dọc, tap target lớn */
    .zb-nav-menu .zb-nav-links { flex-direction: column; align-items: stretch; gap: 2px; }
    .zb-nav-menu .zb-nav-links a {
        padding: 13px 12px; font-size: 16px; font-weight: 600; color: var(--zb-ink);
        border-radius: 10px; display: flex; align-items: center;
    }
    .zb-nav-menu .zb-nav-links a:hover, .zb-nav-menu .zb-nav-links a:active { background: #f5f6fb; color: var(--zb-indigo); }
    /* CTA: 2 nút full-width, tách bằng đường kẻ trên */
    .zb-nav-menu .zb-nav-cta {
        flex-direction: column; align-items: stretch; gap: 10px;
        margin-top: 10px; padding-top: 14px; border-top: 1px solid var(--zb-line);
    }
    .zb-nav-menu .zb-nav-cta .zb-btn {
        width: 100%; justify-content: center; padding: 14px 18px; font-size: 16px; border-radius: 12px;
    }
}
@keyframes zbMenuIn { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: none; } }

/* ---- Auth (login) split-screen ---- */
.zb-auth { min-height: 100vh; display: grid; grid-template-columns: 1.05fr 1fr; }
.zb-auth-brand { background: var(--zb-grad); color: #fff; padding: 56px 52px; display: flex; flex-direction: column; justify-content: space-between; }
.zb-auth-brand .zb-brand { color: #fff; }
.zb-auth-brand .zb-brand .zb-logo { background: rgba(255,255,255,.18); }
.zb-auth-brand h2 { color: #fff; font-size: 34px; margin: 0 0 14px; }
.zb-auth-brand p.tag { color: rgba(255,255,255,.92); font-size: 16px; max-width: 420px; }
.zb-auth-feats { list-style: none; padding: 0; margin: 26px 0 0; }
.zb-auth-feats li { display: flex; align-items: center; gap: 10px; padding: 8px 0; color: rgba(255,255,255,.95); font-size: 15px; }
.zb-auth-feats li i { color: #bbf7d0; font-size: 18px; }
.zb-auth-note { font-size: 13px; color: rgba(255,255,255,.7); }
.zb-auth-form-wrap { display: flex; align-items: center; justify-content: center; padding: 40px 28px; background: #fff; }
.zb-auth-form { width: 100%; max-width: 400px; }
.zb-auth-form h1 { font-size: 28px; margin: 0 0 4px; }
.zb-auth-form .sub { color: var(--zb-muted); margin: 0 0 26px; font-size: 15px; }
.zb-pwd { position: relative; }
.zb-pwd .zb-pwd-toggle { position: absolute; right: 8px; top: 50%; transform: translateY(-50%); background: none; border: none; color: var(--zb-muted); cursor: pointer; font-size: 18px; padding: 6px; }
.zb-auth-form .zb-field input.err { border-color: #dc2626; box-shadow: 0 0 0 3px rgba(220,38,38,.15); }
.zb-auth-row { display: flex; align-items: center; justify-content: space-between; margin: 6px 0 18px; font-size: 14px; }
.zb-auth-row label { display: flex; align-items: center; gap: 7px; color: var(--zb-body); cursor: pointer; }
.zb-auth-mobilebrand { display: none; }
@media (max-width: 860px) {
    .zb-auth { grid-template-columns: 1fr; }
    .zb-auth-brand { display: none; }
    .zb-auth-mobilebrand { display: flex; justify-content: center; margin-bottom: 22px; }
}