/* === LIBRE-S PHONE — STYLE.CSS === */
/* Based on AV Intelligence / EU Robotaxi design system — map section removed. */

:root {
    /* Text colors — never used as backgrounds */
    --text: #1e293b;
    --text-muted: #64748b;
    --text-light: #94a3b8;

    /* Surface colors — backgrounds only */
    --surface: #ffffff;
    --surface-alt: #f1f5f9;
    --surface-card: #ffffff;
    --header-bg: #1e293b;
    --footer-bg: #1e293b;

    /* Brand */
    --blue: #2563eb;
    --blue-light: #dbeafe;
    --green: #16a34a;
    --green-light: #dcfce7;
    --red: #dc2626;
    --red-light: #fee2e2;
    --amber: #f59e0b;
    --amber-light: #fef3c7;
    --gray: #64748b;

    /* Misc */
    --border: #e2e8f0;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --radius: 8px;
}

@media (prefers-color-scheme: dark) {
    :root {
        --text: #e2e8f0;
        --text-muted: #94a3b8;
        --text-light: #64748b;
        --surface: #0f172a;
        --surface-alt: #1e293b;
        --surface-card: #1e293b;
        --header-bg: #0f172a;
        --footer-bg: #0a0a16;
        --border: #334155;
        --shadow: 0 2px 8px rgba(0,0,0,0.3);
    }
    body { background: var(--surface); color: var(--text); }
    .hero { background: linear-gradient(135deg, #0f172a, #1e293b); }
    .stack-item, .stack-equal { background: var(--surface-card); border-color: var(--border); }
    .acronym-card, .advantage-card, .app-card { background: var(--surface-card); border-color: var(--border); }
    footer { background: var(--footer-bg); }
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--surface);
    color: var(--text);
    line-height: 1.6;
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 1rem; }

/* === HEADER === */
header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--header-bg);
    box-shadow: var(--shadow);
}
.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1rem;
    position: relative;
}
.logo {
    font-size: 1.3rem;
    font-weight: 700;
    color: #ffffff;
    text-decoration: none;
}
.logo-accent { color: var(--blue); }
nav { display: flex; gap: 1.25rem; margin-left: auto; }
.nav-link {
    text-decoration: none;
    color: #cbd5e1;
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
}
.nav-link:hover { color: var(--blue); }

/* Hamburger toggle — hidden on desktop, shown on mobile/portrait */
.nav-toggle {
    display: none;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.25);
    color: #fff;
    width: 44px; height: 44px; min-width: 44px; min-height: 44px;
    padding: 0; border-radius: 8px;
    cursor: pointer; margin-left: auto;
    align-items: center; justify-content: center;
    transition: background 0.15s, border-color 0.15s, transform 0.1s;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}
.nav-toggle:hover { background: rgba(37, 99, 235, 0.25); border-color: var(--blue); }
.nav-toggle:active { transform: scale(0.95); }
.nav-toggle:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
.nav-toggle-icon { display: block; pointer-events: none; }
.nav-toggle[aria-expanded="true"] .bar-top    { transform: translateY(5px) rotate(45deg); transform-origin: center; }
.nav-toggle[aria-expanded="true"] .bar-mid    { opacity: 0; }
.nav-toggle[aria-expanded="true"] .bar-bottom { transform: translateY(-5px) rotate(-45deg); transform-origin: center; }
.bar { transition: transform 0.2s ease, opacity 0.15s ease; }

@media (max-width: 900px) {
    .nav-toggle { display: inline-flex; }
    nav#siteNav {
        display: none;
        position: absolute;
        top: 100%; right: 0; left: 0;
        flex-direction: column; gap: 0;
        background: var(--header-bg);
        box-shadow: var(--shadow);
        padding: 0.5rem 0;
        margin-left: 0;
        max-height: calc(100vh - 100%);
        overflow-y: auto; -webkit-overflow-scrolling: touch;
    }
    nav#siteNav.open { display: flex; }
    nav#siteNav .nav-link {
        padding: 0.95rem 1.25rem;
        border-bottom: 1px solid rgba(255,255,255,0.06);
        font-size: 1rem;
        min-height: 44px;
        display: flex; align-items: center;
    }
    nav#siteNav .nav-link:last-child { border-bottom: none; }
}

/* === BUTTONS === */
.btn {
    padding: 0.6rem 1.4rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    display: inline-block;
}
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: #1d4ed8; }

/* === HERO === */
.hero {
    background: linear-gradient(135deg, var(--header-bg), #334155);
    color: #fff;
    padding: 7rem 1rem 3rem;     /* 7rem top — clears the version badge */
    text-align: center;
}
.hero h1 { font-size: 2rem; font-weight: 700; margin-bottom: 1rem; line-height: 1.3; }
.hero h1 { padding-top: 1.5rem; }   /* belt-and-braces clearance */
.highlight { color: var(--blue); }
.hero-sub { font-size: 1.05rem; color: #cbd5e1; margin-bottom: 2rem; max-width: 720px; margin-left: auto; margin-right: auto; }

/* version-badge rule removed */

.hero-stats-frame {
    display: inline-block;
    background: #ffffff;
    border-radius: var(--radius);
    padding: 1.25rem 2.5rem;
    margin-top: 0.5rem;
    box-shadow: var(--shadow);
}
.hero-stats-frame .stat-num { color: var(--blue); }
.hero-stats-frame .stat-label { color: var(--text-muted); }
.hero-stats { display: flex; justify-content: center; gap: 2.5rem; flex-wrap: wrap; }
.stat { text-align: center; }
.stat-num { display: block; font-size: 1.8rem; font-weight: 700; color: var(--blue); }
.stat-label { font-size: 0.85rem; color: #94a3b8; }

@media (max-width: 600px) {
    .hero h1 { font-size: 1.5rem; }
    .hero-stats { gap: 1.5rem; }
    .hero-stats-frame { padding: 1rem 1.5rem; }
}

/* === SECTIONS === */
.section { padding: 2.5rem 1rem; }
.section.bg-alt { background: var(--surface-alt); }
.section h2 { font-size: 1.6rem; font-weight: 700; margin-bottom: 0.5rem; color: var(--text); }
.section-sub { color: var(--text-muted); margin-bottom: 1.5rem; font-size: 0.95rem; }

/* === PROSE (welcome / disclaimer) === */
.prose { max-width: 760px; }
.prose p { margin-bottom: 1rem; color: var(--text); font-size: 0.98rem; }
.prose h3 { font-size: 1.1rem; margin: 1.5rem 0 0.5rem; }
.prose h3.good { color: var(--green); }
.prose h3.bad { color: var(--red); }

/* === STACK LIST (Samsung breakdown) === */
.stack-list { max-width: 760px; margin: 0 auto; }
.stack-item {
    display: flex; align-items: center; gap: 0.75rem;
    background: var(--surface-card);
    border: 1px solid var(--border);
    border-left: 4px solid var(--blue);
    border-radius: var(--radius);
    padding: 0.85rem 1.1rem;
    margin-bottom: 0.6rem;
    font-size: 0.95rem;
    color: var(--text);
    box-shadow: var(--shadow);
}
.stack-item.plus { border-left-color: var(--gray); color: var(--text-muted); }
.stack-item strong { color: var(--text); }
.stack-layer {
    display: inline-block;
    background: var(--blue); color: #fff;
    font-size: 0.7rem; font-weight: 700;
    padding: 0.15rem 0.5rem; border-radius: 4px;
    text-transform: uppercase; letter-spacing: 0.5px;
    white-space: nowrap;
}
.stack-equal {
    background: var(--surface-card);
    border: 2px dashed var(--red);
    border-radius: var(--radius);
    padding: 1rem 1.1rem;
    margin-top: 0.5rem;
    text-align: center;
    font-size: 1.05rem;
    color: var(--red);
}
.stack-equal strong { color: var(--red); }

/* === ACRONYM (Lib-Re-S) === */
.acronym-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
    margin-top: 1.5rem;
}
.acronym-card {
    background: var(--surface-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    text-align: center;
    box-shadow: var(--shadow);
}
.acronym-letter {
    font-size: 1.4rem; font-weight: 700;
    color: var(--blue);
    margin-bottom: 0.25rem;
}
.acronym-word {
    font-size: 1rem; color: var(--text-muted);
    text-transform: uppercase; letter-spacing: 0.5px;
}
@media (max-width: 600px) { .acronym-grid { grid-template-columns: 1fr; } }

/* === ADVANTAGES GRID === */
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
    margin-top: 2rem;
}
.advantage-card {
    background: var(--surface-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: transform 0.15s, box-shadow 0.15s;
}
.advantage-card:hover { transform: translateY(-2px); box-shadow: 0 4px 16px rgba(0,0,0,0.12); }
.advantage-icon {
    display: inline-flex;
    align-items: center; justify-content: center;
    width: 44px; height: 44px;
    border-radius: 8px;
    background: var(--blue-light);
    color: var(--blue);
    font-size: 1.1rem; font-weight: 700;
    margin-bottom: 0.75rem;
}
.advantage-card h3 { font-size: 1.05rem; margin-bottom: 0.4rem; color: var(--text); }
.advantage-card p { font-size: 0.9rem; color: var(--text-muted); line-height: 1.5; }
@media (max-width: 900px) { .advantages-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .advantages-grid { grid-template-columns: 1fr; } }

/* === APP GRID (pre-installed) === */
.app-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.25rem;
}
.app-card {
    background: var(--surface-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
}
.app-card h3 { font-size: 1.05rem; margin-bottom: 0.4rem; color: var(--blue); }
.app-card p { font-size: 0.9rem; color: var(--text-muted); line-height: 1.5; }
@media (max-width: 768px) { .app-grid { grid-template-columns: 1fr; } }

/* === FOOTER === */
footer { background: var(--footer-bg); color: #cbd5e1; padding: 2rem 1rem 1rem; margin-top: 2rem; }
.footer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; margin-bottom: 1.5rem; }
@media (max-width: 768px) { .footer-grid { grid-template-columns: repeat(2, 1fr); } }
.footer-col h4 {
    font-size: 0.9rem; text-transform: uppercase; letter-spacing: 0.5px;
    margin-bottom: 0.75rem; color: #fff;
}
.footer-col a {
    display: block; color: #94a3b8; text-decoration: none;
    font-size: 0.85rem; padding: 0.2rem 0; transition: color 0.2s;
}
.footer-col a:hover { color: #fff; }
.footer-bottom {
    border-top: 1px solid #475569; padding-top: 1rem;
    font-size: 0.8rem; color: #64748b; text-align: center;
}