/* =============================================
   SteamVault Landing — v4
   Warm dark, filled, non-AI aesthetic
   ============================================= */

:root {
    --bg:       #0A0A0E;
    --bg2:      #0F0F14;
    --surface:  #161619;
    --raised:   #1E1E22;
    --hover:    #27272B;

    --accent:   #3073F0;
    --accent-h: #4F8BFA;
    --accent-bg: rgba(48, 115, 240, 0.08);
    --accent-glow: rgba(48, 115, 240, 0.2);

    --t1: #EAEAEC;
    --t2: #8A8A94;
    --t3: #4E4E58;
    --green: #34D399;

    --border: #1C1C22;
    --border-h: #2C2C34;
    --r: 14px;
    --r-sm: 10px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
    background: var(--bg);
    color: var(--t1);
    font-family: 'Inter', -apple-system, sans-serif;
    line-height: 1.6;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
}

body { overflow-x: hidden; }
a { color: inherit; text-decoration: none; }
code { font-family: 'JetBrains Mono', monospace; font-size: 0.88em; background: var(--surface); padding: 2px 7px; border-radius: 5px; color: var(--accent-h); }
::selection { background: var(--accent); color: var(--bg); }
.hidden { display: none !important; }
.accent { color: var(--accent-h); }
.wrap { max-width: 1140px; margin: 0 auto; padding: 0 28px; }

/* ───────── Navbar ───────── */
.navbar { position: fixed; top: 0; left: 0; right: 0; z-index: 100; padding: 14px 28px; }

.nav-inner {
    max-width: 1060px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(10, 10, 14, 0.6);
    backdrop-filter: blur(24px) saturate(150%);
    -webkit-backdrop-filter: blur(24px) saturate(150%);
    border: 1px solid var(--border);
    border-radius: 100px;
    padding: 5px 5px 5px 20px;
    box-shadow: 0 4px 32px rgba(0,0,0,0.5);
}

.nav-brand { display: flex; align-items: center; gap: 10px; color: var(--t1); }
.nav-logo { width: 22px; height: 22px; object-fit: contain; }
.nav-name { font-weight: 600; font-size: 15px; letter-spacing: -0.01em; }
.nav-tag { font-family: 'JetBrains Mono', monospace; font-size: 11px; color: var(--t3); background: var(--surface); padding: 2px 7px; border-radius: 6px; border: 1px solid var(--border); }

.nav-center { display: flex; gap: 28px; }
.nav-center a { font-size: 14px; color: var(--t2); font-weight: 450; transition: color 0.15s; }
.nav-center a:hover { color: var(--t1); }

.nav-right { display: flex; align-items: center; gap: 2px; }
.nav-social { width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; color: var(--t3); border-radius: 50%; transition: all 0.15s; }
.nav-social:hover { color: var(--t1); background: var(--surface); }
.nav-social svg, .nav-social i { width: 18px; height: 18px; }
.nav-cta { margin-left: 8px; padding: 8px 20px; background: var(--t1); color: var(--bg); font-size: 13px; font-weight: 600; border-radius: 100px; transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s; backface-visibility: hidden; transform: translateZ(0); }
.nav-cta:hover { transform: translateY(-2px); box-shadow: 0 4px 20px rgba(255,255,255,0.12); }

/* ───────── Hero ───────── */
.hero {
    padding: 180px 0 120px;
    position: relative;
    overflow: hidden;
}

.hero-glow {
    position: absolute;
    top: -100px;
    left: 30%;
    width: 700px;
    height: 700px;
    background: radial-gradient(circle, rgba(48, 115, 240, 0.06) 0%, transparent 65%);
    pointer-events: none;
}

.hero-wrap {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 60px;
    align-items: center;
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 500;
    color: var(--t2);
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 5px 14px;
    border-radius: 100px;
    margin-bottom: 28px;
}

.chip-dot {
    width: 6px; height: 6px;
    background: var(--green);
    border-radius: 50%;
    box-shadow: 0 0 8px var(--green);
}

.hero h1 {
    font-size: clamp(40px, 5vw, 56px);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: 20px;
}

.hero-sub {
    font-size: 17px;
    color: var(--t2);
    line-height: 1.7;
    margin-bottom: 36px;
    max-width: 500px;
}

.btn-accent, .btn-outline {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    font-size: 14px;
    border-radius: var(--r-sm);
    padding: 12px 24px;
    transition: all 0.2s;
    border: 1px solid transparent;
}

.btn-accent {
    background: var(--accent);
    color: var(--bg);
    box-shadow: 0 2px 16px var(--accent-glow);
}
.btn-accent:hover { background: var(--accent-h); transform: translateY(-1px); box-shadow: 0 6px 28px rgba(255,255,255,0.15); }
.btn-accent i { width: 17px; height: 17px; }

.btn-block { width: 100%; justify-content: center; padding: 14px; }

.btn-outline { border-color: var(--border); color: var(--t1); background: var(--surface); }
.btn-outline:hover { border-color: var(--border-h); background: var(--raised); }
.btn-outline i { width: 17px; height: 17px; }

.hero-btns { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 32px; }

.hero-meta {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}
.hero-meta span { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--t3); font-weight: 450; }
.hero-meta i { width: 15px; height: 15px; color: var(--green); }

/* Hero Visual — stacked floating cards */
.hero-visual {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.visual-card {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--r);
    padding: 18px 22px;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.visual-card:hover { background: var(--raised); border-color: var(--border-h); transform: translateX(-6px); }

.vc1 { transform: translateX(20px); }
.vc2 { transform: translateX(40px); }
.vc3 { transform: translateX(20px); }
.vc4 { transform: translateX(0px); }

.vc-icon {
    width: 40px; height: 40px;
    background: var(--accent-bg);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}
.vc-icon i { width: 20px; height: 20px; color: var(--accent-h); }

.visual-card strong { font-size: 14px; font-weight: 600; display: block; margin-bottom: 2px; }
.visual-card span { font-size: 13px; color: var(--t3); }

/* ───────── Section Common ───────── */
.section-label {
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--accent-h);
    margin-bottom: 12px;
}

.section-title {
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
}

.section-desc {
    font-size: 16px;
    color: var(--t2);
    max-width: 480px;
    margin-bottom: 48px;
}

/* ───────── Marquee ───────── */
.marquee-section {
    width: 100%;
    overflow: hidden;
    background: var(--surface);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    padding: 12px 0;
}
.marquee-inner {
    display: flex;
    width: max-content;
    animation: marquee 50s linear infinite;
}
.marquee-group {
    display: flex;
    flex-shrink: 0;
    gap: 40px;
    padding-right: 40px;
}
.marquee-group span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 500;
    color: var(--t2);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.m-icon { width: 14px; height: 14px; color: var(--accent); }
@keyframes marquee { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }

/* ───────── Features ───────── */
.section-features {
    padding: 100px 0 120px;
    border-top: 1px solid var(--border);
    background: var(--bg2);
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--r);
    padding: 32px;
    transition: all 0.25s;
}
.card:hover { border-color: var(--border-h); background: var(--raised); }

.card-wide { grid-column: span 2; }

.card-top { display: flex; align-items: center; gap: 14px; margin-bottom: 14px; }
.card-icon { width: 40px; height: 40px; background: var(--accent-bg); border-radius: 10px; display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.card-icon i { width: 20px; height: 20px; color: var(--accent-h); }
.card h3 { font-size: 17px; font-weight: 600; }
.card p { font-size: 14px; color: var(--t2); line-height: 1.65; }

.card-code {
    margin-top: 20px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--r-sm);
    padding: 16px 20px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    color: var(--t2);
    line-height: 1.7;
    overflow-x: auto;
}
.cc-kw { color: var(--accent-h); }
.cc-cm { color: var(--t3); }

.card-community { background: linear-gradient(135deg, var(--surface) 0%, rgba(48, 115, 240, 0.03) 100%); }

.card-links { display: flex; gap: 12px; margin-top: 20px; flex-wrap: wrap; }
.clink {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--t2);
    background: var(--bg);
    border: 1px solid var(--border);
    padding: 8px 16px;
    border-radius: 8px;
    transition: all 0.15s;
}
.clink:hover { border-color: var(--border-h); color: var(--t1); }
.clink svg, .clink i { width: 16px; height: 16px; }

/* Theme Switcher */
.card-theme-demo { display: flex; flex-direction: column; }
.theme-interactive { margin-top: 24px; flex-grow: 1; display: flex; flex-direction: column; gap: 20px; }
.theme-swatches { display: flex; gap: 10px; }
.swatch { width: 24px; height: 24px; border-radius: 50%; border: 2px solid transparent; cursor: pointer; transition: transform 0.2s; padding: 0; box-shadow: 0 2px 8px rgba(0,0,0,0.2); }
.swatch:hover { transform: scale(1.1); }
.swatch.active { border-color: var(--accent); transform: scale(1.1); box-shadow: 0 0 0 2px var(--bg), 0 0 0 4px var(--accent); }
.swatch[data-theme="dark"] { background: #161619; }
.swatch[data-theme="amoled"] { background: #000000; }
.swatch[data-theme="midnight"] { background: #0B1120; }
.swatch[data-theme="emerald"] { background: #022C22; }

.theme-mockup {
    background: #161619;
    border: 1px solid rgba(255,255,255,0.05);
    border-radius: var(--r-sm);
    overflow: hidden;
    height: 110px;
    transition: background 0.4s ease;
}
.tm-head { height: 20px; background: rgba(0,0,0,0.2); display: flex; align-items: center; gap: 4px; padding: 0 8px; }
.tm-dot { width: 6px; height: 6px; border-radius: 50%; background: rgba(255,255,255,0.1); }
.tm-body { padding: 12px; display: flex; flex-direction: column; gap: 8px; }
.tm-line { height: 4px; background: rgba(255,255,255,0.08); border-radius: 2px; }
.tm-box { height: 32px; background: var(--accent-bg); border-radius: 4px; border: 1px solid rgba(255,255,255,0.03); }

/* ───────── Pipeline ───────── */
.section-pipeline { padding: 100px 0; border-top: 1px solid var(--border); background: var(--bg); }
.text-center { text-align: center; }
.section-pipeline .section-desc { margin: 0 auto 60px; }

.pipeline-diagram {
    max-width: 800px; margin: 0 auto;
    display: flex; flex-direction: column; align-items: center; gap: 16px;
}
.pipe-node {
    display: inline-flex; align-items: center; gap: 10px;
    background: var(--surface); border: 1px solid var(--border);
    padding: 12px 20px; border-radius: var(--r-sm);
    font-size: 14px; font-weight: 500; z-index: 2; position: relative;
    box-shadow: 0 4px 16px rgba(0,0,0,0.2);
}
.pipe-node i { width: 18px; height: 18px; color: var(--t2); }
.accent-node { border-color: var(--accent); background: var(--accent-bg); }
.accent-node i { color: var(--accent); }
.success-node { border-color: var(--green); background: rgba(52, 211, 153, 0.1); }
.success-node i { color: var(--green); }

.pipe-grid {
    display: flex; gap: 16px; flex-wrap: wrap; justify-content: center;
    position: relative;
}
.pipe-split, .pipe-merge { width: 2px; height: 24px; background: var(--border); }

/* ───────── Download ───────── */
.section-download {
    padding: 100px 0 120px;
    border-top: 1px solid var(--border);
}

.dl-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 72px;
}

.dl-sub { font-size: 15px; color: var(--t2); margin-bottom: 32px; max-width: 400px; line-height: 1.6; }

.dl-box {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--r);
    padding: 24px;
    margin-bottom: 16px;
}

.dl-top { display: flex; align-items: center; gap: 16px; margin-bottom: 20px; }
.dl-logo { width: 48px; height: 48px; object-fit: contain; }
.dl-name { font-size: 18px; font-weight: 600; }
.dl-info { font-size: 13px; color: var(--t3); margin-top: 2px; }

.dl-hash-wrap { }
.hash-label { font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--t3); font-weight: 600; }
.hash-value {
    display: block;
    margin-top: 6px;
    font-size: 11px;
    color: var(--t3);
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 10px 14px;
    border-radius: 8px;
    word-break: break-all;
}

/* Changelog */
.cl-list { display: flex; flex-direction: column; gap: 28px; }

.cl-entry { position: relative; padding-left: 20px; border-left: 2px solid var(--border); }
.cl-entry.latest { border-color: var(--accent); }

.cl-head { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.cl-ver { font-size: 15px; font-weight: 600; }
.cl-date { font-size: 13px; color: var(--t3); }
.cl-badge { font-size: 10px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--accent); background: var(--accent-bg); padding: 2px 8px; border-radius: 4px; }

.cl-changes { list-style: none; }
.cl-changes li { font-size: 14px; color: var(--t2); padding: 3px 0 3px 14px; position: relative; }
.cl-changes li::before { content: ''; position: absolute; left: 0; top: 13px; width: 4px; height: 1px; background: var(--t3); }

/* ───────── FAQ ───────── */
.section-faq {
    padding: 100px 0 120px;
    border-top: 1px solid var(--border);
    background: var(--bg2);
}

.faq-wrap { max-width: 720px; }

.faq-item { border-bottom: 1px solid var(--border); }
.faq-question {
    width: 100%; text-align: left; background: none; border: none; color: var(--t1);
    font-size: 15px; font-weight: 500; padding: 24px 0; cursor: pointer;
    display: flex; justify-content: space-between; align-items: center;
    font-family: inherit; gap: 24px; transition: color 0.15s;
}
.faq-question:hover { color: var(--accent-h); }
.faq-question i { width: 16px; height: 16px; color: var(--t3); flex-shrink: 0; transition: transform 0.3s, color 0.3s; }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s cubic-bezier(0.16, 1, 0.3, 1); }
.faq-answer-inner { padding-bottom: 24px; color: var(--t2); font-size: 14px; line-height: 1.7; }
.faq-item.active .faq-question i { transform: rotate(180deg); color: var(--accent); }

/* ───────── Footer ───────── */
.footer { padding: 36px 0; border-top: 1px solid var(--border); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; }
.f-left { display: flex; align-items: center; gap: 12px; }
.f-logo { width: 20px; height: 20px; object-fit: contain; opacity: 0.4; }
.f-name { font-size: 13px; font-weight: 500; color: var(--t2); }
.f-copy { font-size: 12px; color: var(--t3); }
.f-right { display: flex; gap: 24px; }
.f-right a { font-size: 13px; color: var(--t3); font-weight: 500; transition: color 0.15s; }
.f-right a:hover { color: var(--t1); }

/* ───────── Animations ───────── */
.reveal {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.reveal.visible { opacity: 1; transform: none; }

/* ───────── Responsive ───────── */
@media (max-width: 900px) {
    .hero-wrap { grid-template-columns: 1fr; }
    .hero-right { display: none; }
    .cards-grid { grid-template-columns: 1fr; }
    .card-wide { grid-column: span 1; }
    .dl-grid { grid-template-columns: 1fr; gap: 56px; }
}

@media (max-width: 640px) {
    .navbar { padding: 10px 14px; }
    .nav-inner { padding: 5px 5px 5px 14px; }
    .nav-center { display: none; }
    .hero { padding: 150px 0 80px; }
    .hero h1 { font-size: 36px; }
    .hero-btns { flex-direction: column; }
    .hero-meta { flex-direction: column; gap: 8px; }
    .section-features, .section-download, .section-faq { padding: 80px 0; }
    .footer-inner { flex-direction: column; gap: 20px; text-align: center; }
}