/* Elchi site — the app's own token set (theme.dart), light + dark.
   System fonts only: a no-tracker site loads nothing from anyone. */

:root {
    /* dark (app ElchiTokens.dark) — default */
    --bg: #12141D;
    --panel: #161927;
    --elev: #1E2231;
    --border: rgba(255, 255, 255, 0.07);
    --text: #E9EBF5;
    --muted: #9AA0B5;
    --accent: #0FA47A;
    --accent-hi: #19C08F;
    --on-accent: #FFFFFF;
    --glow: rgba(15, 164, 122, 0.10);
    --shadow: rgba(0, 0, 0, 0.45);
    --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
    --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color-scheme: dark;
}

[data-theme="light"] {
    /* light (app ElchiTokens.light) */
    --bg: #FFFFFF;
    --panel: #F4F5F9;
    --elev: #EEF0F6;
    --border: rgba(20, 24, 50, 0.10);
    --text: #1C1F2E;
    --muted: #666C85;
    --accent: #0FA47A;
    --accent-hi: #0B8562;
    --on-accent: #FFFFFF;
    --glow: rgba(15, 164, 122, 0.08);
    --shadow: rgba(20, 24, 50, 0.14);
    color-scheme: light;
}

@media (prefers-color-scheme: light) {
    :root:not([data-theme]) {
        --bg: #FFFFFF;
        --panel: #F4F5F9;
        --elev: #EEF0F6;
        --border: rgba(20, 24, 50, 0.10);
        --text: #1C1F2E;
        --muted: #666C85;
        --accent: #0FA47A;
        --accent-hi: #0B8562;
        --on-accent: #FFFFFF;
        --glow: rgba(15, 164, 122, 0.08);
        --shadow: rgba(20, 24, 50, 0.14);
        color-scheme: light;
    }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    * { animation: none !important; transition: none !important; }
}

body {
    margin: 0;
    background:
        radial-gradient(1200px 600px at 85% -10%, var(--glow), transparent 60%),
        var(--bg);
    color: var(--text);
    font-family: var(--sans);
    font-size: 17px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.mono { font-family: var(--mono); }
.muted { color: var(--muted); }

a { color: var(--accent); text-decoration: none; }

a:focus-visible,
.btn:focus-visible,
button:focus-visible,
summary:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 3px;
    border-radius: 4px;
}

/* ---------- nav ---------- */
.nav {
    max-width: 1080px;
    margin: 0 auto;
    padding: 22px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text);
    font-weight: 700;
    font-size: 20px;
    letter-spacing: 0.02em;
}

.brand-mark { border-radius: 8px; display: block; }

.nav-links { display: flex; gap: 26px; }

.nav-links a { color: var(--muted); font-size: 15px; }
.nav-links a:hover { color: var(--text); }

.nav-tools { display: flex; align-items: center; gap: 14px; }

.lang { display: flex; gap: 2px; border: 1px solid var(--border); border-radius: 10px; padding: 2px; }

.lang a {
    color: var(--muted);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.06em;
    padding: 4px 8px;
    border-radius: 8px;
}

.lang a:hover { color: var(--text); }

.lang a.lang-on { background: var(--accent); color: var(--on-accent); }

.theme-toggle {
    width: 34px;
    height: 34px;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: var(--panel);
    color: var(--text);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0;
}

.theme-toggle:hover { border-color: var(--accent); }

/* dark shows the sun (tap -> light); light shows the moon (tap -> dark) */
.tt-moon { display: none; }
[data-theme="light"] .tt-sun { display: none; }
[data-theme="light"] .tt-moon { display: block; }
@media (prefers-color-scheme: light) {
    :root:not([data-theme]) .tt-sun { display: none; }
    :root:not([data-theme]) .tt-moon { display: block; }
}

/* ---------- hero ---------- */
.hero {
    max-width: 1080px;
    margin: 0 auto;
    padding: 64px 24px 40px;
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 48px;
    align-items: center;
}

.tagline { color: var(--muted); font-size: 15px; margin: 0 0 10px; }

h1 {
    margin: 0 0 18px;
    font-size: clamp(38px, 5.4vw, 58px);
    line-height: 1.06;
    letter-spacing: -0.025em;
    font-weight: 750;
}

.lede {
    color: var(--muted);
    font-size: 19px;
    max-width: 46ch;
    margin: 0 0 26px;
}

.cta-row { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
    display: inline-block;
    padding: 12px 22px;
    border-radius: 12px;
    font-weight: 600;
    font-size: 16px;
    border: 1px solid transparent;
    cursor: pointer;
}

.btn-primary { background: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-hi); }

.btn-ghost { border-color: var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); }
.btn-ghost[aria-disabled="true"] { color: var(--muted); cursor: default; }
.btn-ghost[aria-disabled="true"]:hover { border-color: var(--border); }

.cta-note { color: var(--muted); font-size: 14px; margin-top: 16px; }

/* ---------- signature: sealed envelope ---------- */
.envelope { margin: 0; animation: rise 0.6s ease-out both; }

@keyframes rise {
    from { opacity: 0; transform: translateY(14px); }
}

.env-caption {
    font-size: 12px;
    letter-spacing: 0.14em;
    color: var(--muted);
    margin-bottom: 10px;
}

.env-card {
    background: linear-gradient(180deg, var(--glow), transparent 55%), var(--panel);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 20px 22px;
    box-shadow: 0 24px 60px var(--shadow);
}

.env-row { display: flex; align-items: center; gap: 12px; padding: 6px 0; }

.env-label {
    font-size: 11px;
    letter-spacing: 0.14em;
    color: var(--muted);
    width: 44px;
}

.env-value { font-size: 15px; }

.env-seal {
    margin-left: auto;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: radial-gradient(circle at 35% 35%, var(--accent-hi), var(--accent) 65%);
    box-shadow: 0 0 0 3px var(--glow);
}

.env-body {
    margin: 14px 0;
    padding: 14px 16px;
    background: var(--elev);
    border: 1px dashed var(--border);
    border-radius: 10px;
    color: var(--muted);
    opacity: 0.8;
    font-size: 12.5px;
    line-height: 1.7;
    white-space: pre-wrap;
    overflow: hidden;
}

.env-foot { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 14px; }

.tick { color: var(--accent); font-weight: 700; }

/* ---------- trust strip ---------- */
.strip {
    max-width: 1080px;
    margin: 24px auto 0;
    padding: 0 24px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.strip-item {
    border-top: 1px solid var(--border);
    padding: 18px 2px 0;
    color: var(--muted);
    font-size: 15px;
}

.strip-item strong { color: var(--text); display: block; margin-bottom: 2px; }

/* ---------- sections ---------- */
.section { max-width: 1080px; margin: 0 auto; padding: 84px 24px 0; }

h2 {
    font-size: clamp(26px, 3.4vw, 36px);
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin: 0 0 14px;
}

.section-sub { color: var(--muted); margin: 0 0 30px; max-width: 60ch; }

.grid {
    margin-top: 34px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}

.card {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 22px;
}

.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }

/* ---------- steps (a real sequence) ---------- */
.steps {
    list-style: none;
    counter-reset: step;
    margin: 34px 0 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}

.steps li {
    counter-increment: step;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 22px;
    position: relative;
}

.steps li::before {
    content: counter(step);
    font-family: var(--mono);
    font-size: 13px;
    color: var(--accent);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 2px 9px;
    display: inline-block;
    margin-bottom: 12px;
}

.steps h3 { margin: 0 0 8px; font-size: 18px; }
.steps p { margin: 0; color: var(--muted); font-size: 15px; }

/* ---------- downloads ---------- */
.dl-grid { grid-template-columns: repeat(3, 1fr); }

.dl-card { display: flex; flex-direction: column; align-items: flex-start; gap: 0; }

.dl-meta { color: var(--muted); font-size: 13px; margin: 0 0 16px; }

.dl-btn { margin-bottom: 10px; }

.dl-soon { opacity: 0.65; }

.checksum {
    font-size: 11.5px;
    color: var(--muted);
    border-top: 1px solid var(--border);
    padding-top: 12px;
    margin: auto 0 0;
    width: 100%;
    letter-spacing: 0.03em;
}

.checksum .hash { color: var(--muted); opacity: 0.75; word-break: break-all; }

.dl-note { color: var(--muted); font-size: 14px; margin-top: 22px; max-width: 70ch; }

/* ---------- FAQ ---------- */
#faq details {
    border: 1px solid var(--border);
    border-radius: 14px;
    background: var(--panel);
    margin-top: 12px;
    padding: 4px 20px;
}

#faq summary {
    cursor: pointer;
    font-weight: 600;
    padding: 14px 0;
    list-style: none;
    position: relative;
    padding-right: 30px;
}

#faq summary::-webkit-details-marker { display: none; }

#faq summary::after {
    content: "+";
    position: absolute;
    right: 4px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--accent);
    font-size: 20px;
    font-weight: 500;
}

#faq details[open] summary::after { content: "–"; }

#faq details p { color: var(--muted); margin: 0 0 16px; font-size: 15px; }

/* ---------- promise ---------- */
.promise { padding-bottom: 20px; }

.promise-card {
    border: 1px solid var(--border);
    background:
        radial-gradient(600px 200px at 20% 0%, var(--glow), transparent 70%),
        var(--panel);
    border-radius: 20px;
    padding: 46px 40px;
    text-align: center;
}

.promise-text {
    font-size: clamp(22px, 3vw, 30px);
    line-height: 1.3;
    letter-spacing: -0.015em;
    font-weight: 650;
    margin: 0;
    max-width: 26ch;
    margin-inline: auto;
}

/* ---------- doc pages (privacy / terms) ---------- */
.doc {
    max-width: 760px;
    margin: 0 auto;
    padding: 40px 24px 80px;
}

.doc h1 { font-size: clamp(28px, 4vw, 40px); letter-spacing: -0.02em; }

.doc h2 { font-size: 22px; margin-top: 38px; }

.doc p, .doc li { color: var(--muted); font-size: 16px; }

.doc strong { color: var(--text); }

.doc .doc-meta { font-size: 14px; border-bottom: 1px solid var(--border); padding-bottom: 18px; }

.doc blockquote {
    margin: 18px 0;
    padding: 12px 18px;
    border-left: 3px solid var(--accent);
    background: var(--panel);
    border-radius: 0 10px 10px 0;
}

/* ---------- footer ---------- */
.footer {
    max-width: 1080px;
    margin: 0 auto;
    padding: 60px 24px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--muted);
    font-size: 14px;
    flex-wrap: wrap;
    gap: 14px;
}

.footer-brand { display: flex; align-items: center; gap: 10px; }
.footer-brand img { border-radius: 5px; }

.footer-links { display: flex; gap: 20px; flex-wrap: wrap; }
.footer-links a { color: var(--muted); }
.footer-links a:hover { color: var(--text); }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
    .hero { grid-template-columns: 1fr; padding-top: 40px; gap: 36px; }
    .grid, .steps, .strip, .dl-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 620px) {
    .nav-links { display: none; }
    .grid, .steps, .strip, .dl-grid { grid-template-columns: 1fr; }
    .section { padding-top: 64px; }
    .promise-card { padding: 34px 22px; }
}