/* =========================================================
   E.Tech BD — shared stylesheet
   ========================================================= */

/* 1. RESET & TOKENS */
* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --bg: #0f0f0f;
    --bg-2: #161616;
    --card: #222;
    --text: #ffffff;
    --muted: #9a9a9a;
    --accent: #00f2ea;
    --line: rgba(255, 255, 255, 0.1);
    --nav-h: 72px;
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Montserrat', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.container { width: min(1140px, 92%); margin: 0 auto; }

/* 2. SCROLL PROGRESS BAR */
.progress {
    position: fixed; top: 0; left: 0; height: 3px; width: 0;
    background: var(--accent); z-index: 1001;
    box-shadow: 0 0 10px var(--accent);
}

/* 3. NAVBAR */
.nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    height: var(--nav-h);
    display: flex; align-items: center; justify-content: space-between;
    padding: 0 4%;
    transition: background 0.3s, backdrop-filter 0.3s;
}
.nav.scrolled { background: rgba(15, 15, 15, 0.85); backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }

.logo { display: inline-flex; align-items: center; gap: 12px; font-weight: 900; font-size: 1.2rem; letter-spacing: 3px; text-transform: uppercase; white-space: nowrap; }
.logo img { width: 44px; height: 44px; object-fit: cover; border-radius: 50%; border: 1px solid var(--line); }
.logo b { font-weight: 900; }
.logo span { color: var(--accent); }

.nav-links { display: flex; gap: 34px; }
.nav-links a {
    font-size: 0.8rem; font-weight: 600; letter-spacing: 3px; text-transform: uppercase;
    color: var(--muted); position: relative; padding: 6px 0; transition: color 0.3s;
}
.nav-links a::after {
    content: ''; position: absolute; left: 0; bottom: 0; height: 2px; width: 0;
    background: var(--accent); transition: width 0.3s;
}
.nav-links a:hover, .nav-links a.active { color: #fff; }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

.menu-btn { display: none; background: none; border: 0; cursor: pointer; width: 34px; height: 26px; position: relative; }
.menu-btn span { position: absolute; left: 0; width: 100%; height: 2px; background: #fff; transition: 0.3s; }
.menu-btn span:nth-child(1) { top: 2px; }
.menu-btn span:nth-child(2) { top: 12px; }
.menu-btn span:nth-child(3) { top: 22px; }
.menu-btn.open span:nth-child(1) { top: 12px; transform: rotate(45deg); }
.menu-btn.open span:nth-child(2) { opacity: 0; }
.menu-btn.open span:nth-child(3) { top: 12px; transform: rotate(-45deg); }

/* 4. SCROLL STAGE — the 3D hero that opens card by card */
.scroll-stage { position: relative; height: 550vh; }

.stage-sticky {
    position: sticky; top: 0;
    height: 100vh; width: 100%;
    perspective: 1000px;
    display: flex; justify-content: center; align-items: center;
    overflow: hidden;
}

.stage-sticky::before {
    content: ''; position: absolute; inset: 0;
    background: radial-gradient(circle at 50% 50%, rgba(40, 40, 40, 0.5) 0%, #000 70%);
    z-index: -1;
}

.hero-content {
    position: absolute; z-index: 10; text-align: center;
    pointer-events: none; text-transform: uppercase; mix-blend-mode: overlay;
    padding: 0 16px;
}
.hero-content h1 {
    font-size: clamp(3.2rem, 11vw, 8rem);
    font-weight: 900; letter-spacing: 10px; line-height: 1; margin-bottom: 20px;
    background: linear-gradient(to right, #fff, #666);
    -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent;
    opacity: 0.8;
}
.hero-content p { font-size: clamp(0.9rem, 2.4vw, 1.5rem); letter-spacing: 5px; color: var(--accent); }

.tilt { transform-style: preserve-3d; transition: transform 0.25s ease-out; }

.carousel {
    position: relative; width: 250px; height: 350px;
    transform-style: preserve-3d;
    will-change: transform;
}

.card {
    position: absolute; left: 15px; top: 15px;
    width: 220px; height: 320px;
    background: var(--card);
    border-radius: 15px; overflow: hidden;
    border: 1px solid var(--line);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    transform-origin: center center;
    cursor: pointer;
    transition: box-shadow 0.3s, border-color 0.3s, scale 0.3s;
}
.card img { width: 100%; height: 100%; object-fit: cover; border-radius: 15px; }
.card:hover, .card:focus-visible {
    box-shadow: 0 0 15px var(--accent);
    border-color: var(--accent);
    scale: 1.1;
}

.card-label {
    position: absolute; left: 0; right: 0; bottom: 0;
    padding: 40px 16px 16px;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.9), transparent);
}
.card-label strong { display: block; font-size: 1rem; letter-spacing: 1px; }
.card-label small { color: var(--accent); font-size: 0.75rem; letter-spacing: 2px; text-transform: uppercase; }

.stage-caption {
    position: absolute; bottom: 9vh; left: 0; right: 0; text-align: center;
    z-index: 11; pointer-events: none; opacity: 0; transition: opacity 0.4s;
}
.stage-caption.show { opacity: 1; }
.stage-caption h3 { font-size: 1.3rem; letter-spacing: 4px; text-transform: uppercase; }
.stage-caption span { color: var(--accent); letter-spacing: 3px; font-size: 0.8rem; text-transform: uppercase; }

.scroll-hint {
    position: absolute; bottom: 3vh; left: 50%; transform: translateX(-50%);
    z-index: 11; font-size: 0.7rem; letter-spacing: 4px; text-transform: uppercase;
    color: var(--muted); display: flex; flex-direction: column; align-items: center; gap: 8px;
    transition: opacity 0.3s;
}
.scroll-hint i { width: 1px; height: 34px; background: linear-gradient(var(--accent), transparent); animation: drip 1.6s infinite; }
@keyframes drip { 0% { transform: scaleY(0); transform-origin: top; } 50% { transform: scaleY(1); transform-origin: top; } 51% { transform-origin: bottom; } 100% { transform: scaleY(0); transform-origin: bottom; } }

/* 5. CONTENT SECTIONS */
.section { padding: 110px 0; position: relative; }
.section.alt { background: var(--bg-2); }

.section-title { font-size: clamp(1.8rem, 4vw, 3rem); font-weight: 900; letter-spacing: 3px; text-transform: uppercase; margin-bottom: 16px; }
.section-title em { font-style: normal; color: var(--accent); }
.section-sub { color: var(--muted); max-width: 620px; margin-bottom: 56px; }

.grid { display: grid; gap: 28px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.box {
    background: var(--card); border: 1px solid var(--line); border-radius: 15px;
    padding: 32px; transition: border-color 0.3s, box-shadow 0.3s, transform 0.3s;
}
.box:hover { border-color: var(--accent); box-shadow: 0 0 15px rgba(0, 242, 234, 0.35); transform: translateY(-4px); }
.box h3 { margin: 14px 0 10px; letter-spacing: 2px; text-transform: uppercase; font-size: 1rem; }
.box p { color: var(--muted); font-size: 0.92rem; }
.box .icon { font-size: 2rem; }

.stat { text-align: center; }
.stat b { display: block; font-size: clamp(2.2rem, 5vw, 3.6rem); font-weight: 900; color: var(--accent); }
.stat span { color: var(--muted); letter-spacing: 3px; text-transform: uppercase; font-size: 0.75rem; }

.btn {
    display: inline-block; padding: 14px 34px; border-radius: 40px;
    border: 1px solid var(--accent); color: var(--accent);
    font-weight: 700; letter-spacing: 3px; font-size: 0.8rem; text-transform: uppercase;
    background: transparent; cursor: pointer; font-family: inherit;
    transition: background 0.3s, color 0.3s, box-shadow 0.3s;
}
.btn:hover { background: var(--accent); color: #000; box-shadow: 0 0 20px var(--accent); }

.cta { text-align: center; }
.cta .section-sub { margin-left: auto; margin-right: auto; }

/* 6. PAGE HEADER (pages without the scroll hero use this) */
.page-head { padding: calc(var(--nav-h) + 90px) 0 60px; text-align: center; }
.page-head h1 { font-size: clamp(2.4rem, 7vw, 5rem); font-weight: 900; letter-spacing: 8px; text-transform: uppercase; }
.page-head p { color: var(--accent); letter-spacing: 5px; text-transform: uppercase; margin-top: 12px; }

/* 7. TEAM / WORK GRID CARDS */
.person, .work { border-radius: 15px; overflow: hidden; background: var(--card); border: 1px solid var(--line); transition: 0.3s; }
.person:hover, .work:hover { border-color: var(--accent); box-shadow: 0 0 15px rgba(0, 242, 234, 0.35); transform: translateY(-4px); }
.person img { aspect-ratio: 4 / 5; width: 100%; object-fit: cover; }
.work img { aspect-ratio: 16 / 10; width: 100%; object-fit: cover; }
.person div, .work div { padding: 20px; }
.person h3, .work h3 { letter-spacing: 2px; text-transform: uppercase; font-size: 1rem; }
.person small, .work small { color: var(--accent); letter-spacing: 2px; text-transform: uppercase; font-size: 0.72rem; }
.work p { color: var(--muted); font-size: 0.88rem; margin-top: 8px; }

.filters { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 40px; }
.filters button {
    background: transparent; color: var(--muted); border: 1px solid var(--line);
    padding: 10px 22px; border-radius: 30px; cursor: pointer; font-family: inherit;
    letter-spacing: 2px; text-transform: uppercase; font-size: 0.72rem; font-weight: 600; transition: 0.3s;
}
.filters button:hover, .filters button.active { color: #000; background: var(--accent); border-color: var(--accent); }
.work.hide { display: none; }

/* 8. TIMELINE (about page) */
.timeline { border-left: 2px solid var(--line); padding-left: 32px; display: grid; gap: 36px; }
.timeline div { position: relative; }
.timeline div::before {
    content: ''; position: absolute; left: -41px; top: 6px; width: 16px; height: 16px;
    border-radius: 50%; background: var(--bg); border: 2px solid var(--accent);
}
.timeline b { color: var(--accent); letter-spacing: 3px; }
.timeline h3 { margin: 4px 0; text-transform: uppercase; letter-spacing: 2px; font-size: 1rem; }
.timeline p { color: var(--muted); font-size: 0.92rem; }

/* 9. CONTACT FORM */
form { display: grid; gap: 18px; }
label { display: grid; gap: 8px; font-size: 0.75rem; letter-spacing: 3px; text-transform: uppercase; color: var(--muted); }
input, textarea, select {
    width: 100%; background: var(--bg); color: #fff; border: 1px solid var(--line);
    border-radius: 10px; padding: 14px 16px; font-family: inherit; font-size: 0.95rem;
    transition: border-color 0.3s, box-shadow 0.3s;
}
input:focus, textarea:focus, select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 10px rgba(0, 242, 234, 0.35); }
textarea { min-height: 150px; resize: vertical; }
.form-note { color: var(--accent); min-height: 1.4em; font-size: 0.9rem; }

/* 10. FOOTER */
.footer { border-top: 1px solid var(--line); padding: 60px 0 30px; background: #0a0a0a; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer p, .footer li { color: var(--muted); font-size: 0.9rem; }
.footer h4 { letter-spacing: 3px; text-transform: uppercase; font-size: 0.8rem; margin-bottom: 16px; }
.footer li { margin-bottom: 8px; }
.footer a:hover { color: var(--accent); }
.copy { text-align: center; color: var(--muted); font-size: 0.78rem; letter-spacing: 2px; border-top: 1px solid var(--line); padding-top: 24px; }

/* 11. SCROLL REVEAL */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* 12. RESPONSIVE */
@media (max-width: 960px) {
    .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .menu-btn { display: block; }
    .nav-links {
        position: fixed; top: var(--nav-h); left: 0; right: 0;
        flex-direction: column; gap: 0; background: rgba(10, 10, 10, 0.97);
        border-bottom: 1px solid var(--line);
        max-height: 0; overflow: hidden; transition: max-height 0.4s;
    }
    .nav-links.open { max-height: 420px; }
    .nav-links a { padding: 18px 8%; display: block; }
    .nav-links a::after { display: none; }

    .tilt { scale: 0.6; }
    .hero-content h1 { letter-spacing: 4px; }
    .logo { font-size: 1rem; letter-spacing: 2px; }
    .logo img { width: 36px; height: 36px; }
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .section { padding: 80px 0; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .reveal { opacity: 1; transform: none; transition: none; }
    .scroll-hint i { animation: none; }
}