/*
 * Kobra Messenger — landing page styles.
 * Single file, no build step. Editable by hand.
 * Visual identity: deep black base, neon green primary, generous whitespace.
 */

:root {
    --bg: #05070a;
    --bg-alt: #0c1115;
    --surface: #141c22;
    --text: #e6f4ec;
    --text-muted: #7a8a85;
    --primary: #7fff3f;
    --primary-bright: #a3ff66;
    --primary-dark: #1f8a47;
    --danger: #ff4d4d;
    --radius: 14px;
    --container: 1080px;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
                 Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a { color: var(--primary); text-decoration: none; transition: color 0.15s ease; }
a:hover { color: var(--primary-bright); text-decoration: underline; }
code { font-family: "SF Mono", Monaco, Consolas, "Liberation Mono", monospace;
       background: rgba(127, 255, 63, 0.08); padding: 0.1em 0.35em; border-radius: 4px;
       color: var(--primary-bright); font-size: 0.9em; }
pre { background: var(--bg); border: 1px solid rgba(127,255,63,0.15); border-radius: 10px;
      padding: 14px 16px; overflow-x: auto; margin-top: 12px; }
pre code { background: transparent; padding: 0; }

/* ---------- hero ---------- */

.hero {
    background: radial-gradient(ellipse at top, rgba(127,255,63,0.08) 0%, transparent 60%),
                linear-gradient(to bottom, var(--bg) 0%, var(--bg-alt) 100%);
    min-height: 100vh;
    padding-bottom: 80px;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 32px;
    max-width: var(--container);
    margin: 0 auto;
}
.nav-brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 1.05rem; }
.nav-logo { width: 32px; height: 32px; }
.nav-links { display: flex; gap: 24px; align-items: center; }
.nav-links a { color: var(--text); font-size: 0.95rem; }
.nav-links a:hover { color: var(--primary); text-decoration: none; }
.nav-github {
    border: 1px solid var(--primary-dark);
    padding: 6px 14px !important;
    border-radius: 999px;
}

.hero-content {
    max-width: 820px;
    margin: 80px auto 0;
    padding: 0 32px;
    text-align: center;
}
.hero-logo { width: 140px; height: 140px; margin-bottom: 30px;
             filter: drop-shadow(0 0 30px rgba(127,255,63,0.5)); }
.hero-content h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    line-height: 1.15;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 24px;
}
.hero-content h1 em {
    color: var(--primary);
    font-style: normal;
    text-shadow: 0 0 20px rgba(127,255,63,0.3);
}
.hero-sub {
    font-size: 1.15rem;
    color: var(--text-muted);
    max-width: 620px;
    margin: 0 auto 36px;
}
.hero-ctas {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 40px;
}
.hero-banner {
    display: inline-block;
    border: 1px solid rgba(255,77,77,0.4);
    background: rgba(255,77,77,0.08);
    color: var(--danger);
    padding: 10px 20px;
    border-radius: 999px;
    font-size: 0.9rem;
    font-weight: 500;
}

/* ---------- CTAs ---------- */

.cta {
    display: inline-block;
    padding: 14px 28px;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.2s ease;
    border: 2px solid transparent;
    cursor: pointer;
    font-family: inherit;
}
.cta-primary {
    background: var(--primary);
    color: var(--bg) !important;
    border-color: var(--primary);
}
.cta-primary:hover {
    background: var(--primary-bright);
    border-color: var(--primary-bright);
    text-decoration: none;
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(127,255,63,0.25);
}
.cta-secondary {
    color: var(--text) !important;
    border-color: var(--text-muted);
}
.cta-secondary:hover {
    border-color: var(--primary);
    color: var(--primary) !important;
    text-decoration: none;
}

/* ---------- sections ---------- */

.section { padding: 100px 32px; }
.section-alt { background: var(--bg-alt); }
.container { max-width: var(--container); margin: 0 auto; }
.section h2 {
    font-size: clamp(1.7rem, 3.5vw, 2.4rem);
    margin-bottom: 40px;
    text-align: center;
    letter-spacing: -0.01em;
}
.section h3 { font-size: 1.2rem; margin-bottom: 12px; color: var(--primary); }
.section-lead { text-align: center; color: var(--text-muted); margin-bottom: 40px; font-size: 1.1rem; }
.note {
    color: var(--text-muted);
    font-size: 0.95rem;
    max-width: 800px;
    margin: 30px auto 0;
    text-align: center;
    padding: 16px 24px;
    border-left: 3px solid var(--primary-dark);
    background: rgba(127,255,63,0.03);
    border-radius: 0 8px 8px 0;
}

.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid-2-features { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }

.card {
    background: var(--surface);
    border: 1px solid rgba(127,255,63,0.08);
    border-radius: var(--radius);
    padding: 28px 24px;
    transition: border-color 0.2s ease, transform 0.2s ease;
}
.card:hover { border-color: rgba(127,255,63,0.25); transform: translateY(-2px); }
.card-icon { font-size: 2rem; margin-bottom: 14px; }
.card p { color: var(--text-muted); font-size: 0.95rem; }
.card p strong { color: var(--text); }

.panel {
    background: var(--surface);
    padding: 28px;
    border-radius: var(--radius);
    border-top: 3px solid;
}
.panel-positive { border-top-color: var(--primary); }
.panel-negative { border-top-color: var(--danger); }
.panel ul { list-style: none; }
.panel li { padding: 10px 0; border-bottom: 1px solid rgba(255,255,255,0.05);
            color: var(--text-muted); font-size: 0.95rem; }
.panel li:last-child { border-bottom: none; }

.feature-list { list-style: none; }
.feature-list li {
    padding: 12px 0 12px 28px;
    position: relative;
    color: var(--text-muted);
    border-bottom: 1px solid rgba(255,255,255,0.04);
}
.feature-list li::before {
    content: "✓";
    position: absolute;
    left: 4px;
    color: var(--primary);
    font-weight: 700;
}
.feature-list li strong { color: var(--text); }

/* ---------- download ---------- */

.center { text-align: center; }
.download-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
    margin: 40px 0;
}
.download-card {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--surface);
    border: 1px solid rgba(127,255,63,0.1);
    padding: 20px;
    border-radius: var(--radius);
    color: var(--text) !important;
    text-align: left;
    transition: all 0.2s ease;
}
.download-card:hover { border-color: var(--primary); text-decoration: none; }
.download-card[aria-disabled="true"] { opacity: 0.55; cursor: not-allowed; }
.download-icon { font-size: 1.6rem; width: 36px; text-align: center; color: var(--primary); }
.download-title { font-weight: 600; margin-bottom: 2px; }
.download-sub { color: var(--text-muted); font-size: 0.85rem; }

/* ---------- donation ---------- */

.donate-card {
    background: var(--surface);
    border: 2px solid var(--primary-dark);
    border-radius: var(--radius);
    padding: 32px 24px;
    max-width: 600px;
    margin: 30px auto 0;
    text-align: center;
}
.donate-label {
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    margin-bottom: 12px;
}
.donate-address {
    padding: 16px;
    background: var(--bg);
    border-radius: 10px;
    margin: 20px 0;
    overflow-wrap: anywhere;
}
.donate-address code { color: var(--primary-bright); font-size: 0.9rem; }
.disclaim {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-top: 20px;
    line-height: 1.5;
}
.use-list {
    max-width: 600px;
    margin: 20px auto 0;
    padding-left: 30px;
    color: var(--text-muted);
    text-align: left;
}
.use-list li { padding: 8px 0; }

/* ---------- footer ---------- */

.footer {
    background: var(--bg);
    padding: 60px 32px 30px;
    border-top: 1px solid rgba(127,255,63,0.1);
}
.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 40px;
    max-width: var(--container);
    margin: 0 auto 30px;
}
.footer-logo { width: 40px; height: 40px; margin-bottom: 12px; opacity: 0.8; }
.footer-grid p { color: var(--text-muted); font-size: 0.9rem; }
.footer-grid h4 { color: var(--text); font-size: 0.9rem; margin-bottom: 14px; }
.footer-grid a {
    display: block;
    color: var(--text-muted);
    font-size: 0.9rem;
    padding: 4px 0;
}
.footer-grid a:hover { color: var(--primary); text-decoration: none; }
.footer-fine {
    color: var(--text-muted);
    font-size: 0.8rem;
    text-align: center;
    margin-top: 30px;
    max-width: var(--container);
    margin-left: auto;
    margin-right: auto;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.05);
}

/* ---------- responsive ---------- */

@media (max-width: 720px) {
    .nav { padding: 16px 20px; }
    .nav-links a:not(.nav-github) { display: none; }
    .section { padding: 60px 20px; }
    .hero-content { margin-top: 40px; padding: 0 20px; }
    .hero-logo { width: 100px; height: 100px; }
}

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