/* =========================================================
   JS Technology — রঙ ব্যবস্থা (লোগো ও আইকন থেকে নেওয়া)
   ---------------------------------------------------------
   প্রাইমারি  #0A74BC  লোগোর মূল নীল — লিংক, বাটন, হেডিং অ্যাকসেন্ট
   রয়্যাল    #2454A8  আইকনের গাঢ় নীল — গ্রেডিয়েন্টের গভীর অংশ
   স্কাই     #4FA8E0  লোগোর ওয়াইফাই তরঙ্গ — হাইলাইট, আইকন
   নেভি      #0A1F3F  ডার্ক সেকশন, ফুটার
   অ্যাকসেন্ট #FF8A1F  নীলের পরিপূরক কমলা — শুধু প্রধান CTA-তে
   ========================================================= */
:root {
    --primary: #0A74BC;
    --primary-600: #075F9E;
    --royal: #2454A8;
    --sky: #4FA8E0;
    --sky-50: #EEF6FC;
    --sky-100: #DDEEFA;
    --navy: #0A1F3F;
    --navy-800: #0F2B52;
    --ink: #0C1B33;
    --text: #3A4A60;
    --muted: #66768C;
    --line: #DCE6F0;
    --bg: #F6F9FC;
    --white: #FFFFFF;
    --accent: #FF8A1F;
    --accent-600: #EB7405;
    --success: #12A150;
    --danger: #D93A3A;

    --grad-brand: linear-gradient(135deg, #4FA8E0 0%, #0A74BC 48%, #2454A8 100%);
    --grad-dark: linear-gradient(160deg, #0F2B52 0%, #0A1F3F 60%, #081830 100%);

    --font-head: "Anek Bangla", "Hind Siliguri", "Noto Sans Bengali", system-ui, sans-serif;
    --font-body: "Hind Siliguri", "Noto Sans Bengali", system-ui, sans-serif;

    --radius-sm: 8px;
    --radius: 14px;
    --radius-lg: 22px;
    --shadow-sm: 0 1px 2px rgba(12, 27, 51, .06), 0 2px 8px rgba(12, 27, 51, .04);
    --shadow: 0 10px 30px -12px rgba(10, 60, 110, .22);
    --shadow-lg: 0 24px 60px -20px rgba(10, 50, 100, .35);
    --container: 1200px;
}

/* ইংরেজি সংস্করণের ফন্ট */
html[lang="en"] {
    --font-head: "Plus Jakarta Sans", "Segoe UI", system-ui, sans-serif;
    --font-body: "Inter", "Segoe UI", system-ui, sans-serif;
}
html[lang="en"] body { font-size: 16px; line-height: 1.7; }
html[lang="en"] h1, html[lang="en"] h2 { letter-spacing: -0.02em; }

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    margin: 0;
    font-family: var(--font-body);
    font-size: 17px;
    line-height: 1.75;
    color: var(--text);
    background: var(--white);
    overflow-x: hidden;
}
img, svg { max-width: 100%; display: block; }
/* display: grid/flex দেওয়া এলিমেন্টেও hidden অ্যাট্রিবিউট যেন কাজ করে */
[hidden] { display: none !important; }
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-600); }
h1, h2, h3, h4 { font-family: var(--font-head); color: var(--ink); line-height: 1.3; margin: 0 0 .5em; font-weight: 700; }
h1 { font-size: clamp(2rem, 4.6vw, 3.4rem); }
h2 { font-size: clamp(1.6rem, 3.2vw, 2.4rem); }
h3 { font-size: 1.25rem; }
p { margin: 0 0 1em; }
ul { margin: 0; padding: 0; list-style: none; }
:focus-visible { outline: 3px solid var(--sky); outline-offset: 2px; border-radius: 4px; }

.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 20px; }
.icon { width: 1.1em; height: 1.1em; flex-shrink: 0; }
.section { padding: 88px 0; }
.section--tint { background: var(--bg); }
.section--dark { background: var(--grad-dark); color: #C6D4E6; }
.section--dark h2, .section--dark h3 { color: var(--white); }

.section-head { max-width: 680px; margin: 0 auto 52px; text-align: center; }
.section-head p { color: var(--muted); font-size: 1.05rem; }
.section--dark .section-head p { color: #9FB2CB; }
.eyebrow {
    display: inline-flex; align-items: center; gap: 8px;
    font-family: var(--font-head); font-weight: 600; font-size: .9rem;
    color: var(--primary); background: var(--sky-50);
    padding: 4px 14px; border-radius: 999px; margin-bottom: 14px;
}
.section--dark .eyebrow { background: rgba(79, 168, 224, .14); color: var(--sky); }
.text-grad { background: var(--grad-brand); -webkit-background-clip: text; background-clip: text; color: transparent; }

/* ---------- বাটন ---------- */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    font-family: var(--font-head); font-weight: 600; font-size: 1rem; line-height: 1;
    padding: 14px 24px; border-radius: 999px; border: 2px solid transparent;
    cursor: pointer; transition: transform .2s, box-shadow .2s, background .2s, color .2s;
    white-space: nowrap;
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--primary); color: var(--white); box-shadow: 0 8px 20px -8px rgba(10, 116, 188, .7); }
.btn--primary:hover { background: var(--primary-600); color: var(--white); }
.btn--accent { background: var(--accent); color: var(--ink); box-shadow: 0 8px 20px -8px rgba(255, 138, 31, .75); }
.btn--accent:hover { background: var(--accent-600); color: var(--ink); }
.btn--ghost { border-color: var(--line); color: var(--ink); background: var(--white); }
.btn--ghost:hover { border-color: var(--primary); color: var(--primary); }
.btn--outline-light { border-color: rgba(255, 255, 255, .35); color: var(--white); }
.btn--outline-light:hover { background: rgba(255, 255, 255, .1); color: var(--white); }
.btn--white { background: var(--white); color: var(--primary); }
.btn--white:hover { color: var(--royal); }
.btn--block { width: 100%; }

/* ---------- টপবার ও হেডার ---------- */
.topbar { background: var(--navy); color: #AFC2DA; font-size: .88rem; }
.topbar__inner { display: flex; justify-content: space-between; align-items: center; gap: 16px; min-height: 40px; }
.topbar__item, .topbar__links a { display: inline-flex; align-items: center; gap: 6px; }
.topbar__links { display: flex; gap: 22px; }
.topbar__links a { color: #DCE7F5; }
.topbar__links a:hover { color: var(--white); }
.topbar .icon { color: var(--sky); }

/* ভাষা বদলের বাটন */
.lang-switch {
    display: inline-flex; align-items: center; gap: 2px; padding: 3px;
    border-radius: 999px; background: rgba(255, 255, 255, .08); border: 1px solid rgba(255, 255, 255, .14);
}
.topbar__links .lang-switch a {
    display: inline-block; padding: 0 12px; border-radius: 999px; line-height: 1.9;
    font-family: "Hind Siliguri", "Inter", system-ui, sans-serif; font-size: .82rem; font-weight: 600; color: #C9D8EA;
}
.topbar__links .lang-switch a:hover { color: var(--white); }
.topbar__links .lang-switch a.is-active { background: var(--primary); color: var(--white); }

.site-header {
    position: sticky; top: 0; z-index: 50;
    background: rgba(255, 255, 255, .92);
    backdrop-filter: saturate(160%) blur(10px); -webkit-backdrop-filter: saturate(160%) blur(10px);
    border-bottom: 1px solid transparent; transition: box-shadow .25s, border-color .25s;
}
.site-header.is-scrolled { border-color: var(--line); box-shadow: var(--shadow-sm); }
.nav { display: flex; align-items: center; justify-content: space-between; min-height: 76px; gap: 20px; }
.brand img { height: 54px; width: auto; }
.nav__menu { display: flex; align-items: center; gap: 28px; }
.nav__menu ul { display: flex; gap: 4px; }
.nav__menu ul a {
    position: relative; display: block; padding: 8px 14px;
    font-family: var(--font-head); font-weight: 600; font-size: 1.02rem; color: var(--ink); border-radius: 8px;
}
.nav__menu ul a:hover { color: var(--primary); background: var(--sky-50); }
.nav__menu ul a.is-active { color: var(--primary); }
.nav__menu ul a.is-active::after {
    content: ""; position: absolute; left: 14px; right: 14px; bottom: 2px; height: 3px;
    border-radius: 3px; background: var(--grad-brand);
}
.nav__toggle {
    display: none; width: 46px; height: 46px; border-radius: 12px;
    border: 1px solid var(--line); background: var(--white); color: var(--ink);
    align-items: center; justify-content: center; cursor: pointer;
}
.nav__toggle .icon { width: 24px; height: 24px; }

/* ---------- পেজ হিরো (ভেতরের পাতা) ---------- */
.page-hero { position: relative; overflow: hidden; background: var(--grad-dark); color: #BFD0E4; padding: 72px 0 80px; }
.page-hero::before {
    content: ""; position: absolute; inset: 0;
    background:
        radial-gradient(600px 300px at 85% 0%, rgba(79, 168, 224, .28), transparent 70%),
        radial-gradient(500px 260px at 0% 100%, rgba(36, 84, 168, .35), transparent 70%);
}
.page-hero .container { position: relative; }
.page-hero h1 { color: var(--white); margin-bottom: .3em; }
.page-hero p { max-width: 640px; font-size: 1.1rem; margin: 0; }
.breadcrumb { display: flex; gap: 8px; font-size: .92rem; margin-bottom: 14px; color: #8FA6C2; }
.breadcrumb a { color: var(--sky); }

/* ---------- CTA ব্যান্ড ---------- */
.cta-band { background: var(--grad-brand); color: #E6F2FC; padding: 56px 0; position: relative; overflow: hidden; }
.cta-band::after {
    content: ""; position: absolute; right: -80px; top: -120px; width: 380px; height: 380px; border-radius: 50%;
    border: 50px solid rgba(255, 255, 255, .08); pointer-events: none;
}
.cta-band__inner { position: relative; z-index: 1; display: flex; align-items: center; justify-content: space-between; gap: 32px; }
.cta-band h2 { color: var(--white); font-size: clamp(1.45rem, 2.6vw, 2rem); margin-bottom: .3em; }
.cta-band p { margin: 0; max-width: 620px; }
.cta-band__actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* ---------- ফুটার ---------- */
.site-footer { background: var(--navy); color: #9EB1C9; font-size: .96rem; }
.footer__grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.3fr; gap: 40px; padding: 72px 20px 48px; }
.site-footer h3 { color: var(--white); font-size: 1.1rem; margin-bottom: 18px; }
.footer__logo { height: 58px; width: auto; margin-bottom: 18px; background: var(--white); padding: 8px 14px; border-radius: 12px; }
.footer__links li { margin-bottom: 8px; }
.footer__links a { color: #B4C4D8; }
.footer__links a:hover { color: var(--sky); }
.footer__contact li { display: flex; gap: 10px; margin-bottom: 12px; align-items: flex-start; }
.footer__contact .icon { color: var(--sky); margin-top: 6px; }
.footer__contact a { color: #D5E1F0; }
.social { display: flex; gap: 10px; }
.social a {
    width: 40px; height: 40px; border-radius: 10px; display: grid; place-items: center;
    background: rgba(255, 255, 255, .07); color: #D5E1F0; transition: background .2s;
}
.social a:hover { background: var(--primary); color: var(--white); }
.footer__bottom { border-top: 1px solid rgba(255, 255, 255, .08); }
.footer__bottom-inner { display: flex; justify-content: space-between; gap: 12px; padding-top: 18px; padding-bottom: 18px; font-size: .88rem; }
.footer__bottom p { margin: 0; }
.footer__bottom .credit { margin-left: 6px; }
.footer__bottom .credit a { color: var(--sky); font-weight: 600; }
.footer__bottom .credit a:hover { color: var(--white); text-decoration: underline; }

.float-chat {
    position: fixed; right: 20px; bottom: 20px; z-index: 60;
    width: 56px; height: 56px; border-radius: 50%; display: grid; place-items: center;
    background: #25D366; color: var(--white); box-shadow: 0 10px 24px -8px rgba(37, 211, 102, .8);
    transition: transform .2s;
}
.float-chat:hover { transform: scale(1.08); color: var(--white); }
.float-chat .icon { width: 26px; height: 26px; }

/* ---------- রিভিল অ্যানিমেশন ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .reveal { opacity: 1; transform: none; transition: none; }
    *, *::before, *::after { animation: none !important; }
    .gauge__arc { stroke-dashoffset: 40; }
}