/* SrednaBG landing page — dark, cookie-free, system-font first.
   Locked theme: Carbon (warm charcoal + green). Locked font: Geometric. */

:root {
  /* Carbon theme */
  --bg-0: #0b0a08;
  --bg-1: #14120f;
  --bg-2: #1d1a16;
  --bg-3: #272320;
  --stroke: #3a332d;
  --stroke-soft: #241f1b;
  --text-high: #f5f1ea;
  --text-mid: #beb5a7;
  --text-low: #827a6d;
  --accent: #4CAF50;
  --accent-ink: #0b0a08;
  --green: #2E7D32;
  --amber: #F9A825;
  --red: #C62828;
  --focus: #4CAF50;

  /* Geometric font set */
  --font-display: -apple-system, BlinkMacSystemFont, "Segoe UI Variable Display", "Segoe UI", system-ui, "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --display-tracking: -0.02em;
  --display-weight: 700;
  --body-weight: 400;
  --body-tracking: 0;
}

/* ======================================================== base ======== */

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

html { background: var(--bg-0); }

body {
  margin: 0;
  background: var(--bg-0);
  color: var(--text-high);
  font-family: var(--font-body);
  font-weight: var(--body-weight);
  font-size: 16px;
  line-height: 1.55;
  letter-spacing: var(--body-tracking);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

img, svg { display: block; max-width: 100%; }
img { height: auto; }

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

button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 4px;
}

::selection { background: var(--accent); color: var(--accent-ink); }

/* Skip link */
.skip {
  position: absolute;
  left: 12px; top: -40px;
  padding: 8px 12px;
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
  z-index: 100;
  transition: top 150ms ease;
}
.skip:focus { top: 12px; }

/* Container */
.wrap {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}
@media (max-width: 560px) { .wrap { padding: 0 18px; } }

/* Type scale — display uses the display font */
h1, h2, h3, .display {
  font-family: var(--font-display);
  font-weight: var(--display-weight);
  letter-spacing: var(--display-tracking);
  line-height: 1.1;
  margin: 0;
  text-wrap: balance;
}
h1 { font-size: clamp(36px, 6vw, 64px); }
h2 { font-size: clamp(28px, 4vw, 44px); }
h3 { font-size: 18px; font-weight: 600; letter-spacing: 0; line-height: 1.3; }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}

.lede { color: var(--text-mid); font-size: 17px; line-height: 1.6; text-wrap: pretty; }

/* ========================================================= header ===== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in oklab, var(--bg-0) 92%, transparent);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--stroke-soft);
}
.header-row {
  display: flex; align-items: center; gap: 20px;
  height: 64px;
}
.brand {
  display: flex; align-items: center; gap: 8px;
  color: var(--text-high);
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.01em;
  font-size: 17px;
}
.brand svg { width: 28px; height: 28px; color: var(--accent); transform: translateY(2px); }
.brand:hover { color: var(--text-high); }
.brand .wm-sub { color: var(--text-low); font-weight: 400; margin-left: 2px; font-size: 13px; letter-spacing: 0; }

.nav-links {
  display: flex; gap: 24px;
  list-style: none; padding: 0;
}
.nav-links a {
  color: var(--text-mid);
  font-size: 14px;
  padding: 6px 2px;
  border-bottom: 1px solid transparent;
}
.nav-links a:hover { color: var(--text-high); border-bottom-color: var(--accent); }

.header-right { display: flex; align-items: center; gap: 10px; margin-left: auto; }

/* Lang pill */
.lang-pill {
  display: inline-flex;
  background: var(--bg-2);
  border: 1px solid var(--stroke);
  border-radius: 999px;
  padding: 2px;
  overflow: hidden;
}
.lang-pill button {
  padding: 6px 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--text-mid);
  border-radius: 999px;
  transition: background 180ms ease, color 180ms ease;
}
.lang-pill button[aria-pressed="true"] {
  background: var(--bg-3);
  color: var(--text-high);
}
.lang-pill button:hover { color: var(--text-high); }

.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px;
  border-radius: 999px;
  color: var(--text-mid);
  border: 1px solid var(--stroke);
  background: var(--bg-2);
  transition: color 180ms ease, border-color 180ms ease;
}
.icon-btn:hover { color: var(--text-high); border-color: var(--stroke); }
.icon-btn svg { width: 18px; height: 18px; }

@media (max-width: 820px) {
  .nav-links { display: none; }
}

/* ======================================================== sections ==== */

section { padding: 88px 0; position: relative; }
@media (max-width: 680px) { section { padding: 64px 0; } }

.section-head { display: flex; flex-direction: column; gap: 12px; margin-bottom: 40px; max-width: 720px; }

/* rule between sections, subtle */
.divider {
  height: 1px;
  background: var(--stroke-soft);
  margin: 0;
}

/* =========================================================== hero ===== */

.hero {
  padding-top: 96px;
  padding-bottom: 96px;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 64px;
  align-items: center;
}
.hero-copy { display: flex; flex-direction: column; gap: 20px; }
.hero h1 { margin-top: 4px; }
.hero .lede { max-width: 52ch; }

.hero-ctas { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 8px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 13px 20px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0;
  border: 1px solid transparent;
  transition: background 180ms ease, color 180ms ease, border-color 180ms ease, transform 240ms ease;
}
.btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
}
.btn-primary:hover { color: var(--accent-ink); filter: brightness(1.06); }
.btn-secondary {
  background: transparent;
  color: var(--text-high);
  border-color: var(--stroke);
}
.btn-secondary:hover { border-color: var(--text-mid); color: var(--text-high); }
.btn svg { width: 16px; height: 16px; }

/* AA hero slot — 16:9 dark card, robust to missing image */
.aa-slot {
  position: relative;
  aspect-ratio: 16 / 9;
  background: var(--bg-1);
  border: 1px solid var(--stroke);
  border-radius: 16px;
  overflow: hidden;
  display: flex; align-items: center; justify-content: center;
}
.aa-slot img {
  width: 100%; height: 100%;
  object-fit: contain;
  background: var(--bg-1);
}
.aa-slot .aa-placeholder {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; gap: 10px;
  align-items: center; justify-content: center;
  text-align: center; padding: 24px;
  color: var(--text-mid);
}
.aa-slot .aa-placeholder .badge {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--text-low);
  padding: 6px 10px;
  border: 1px solid var(--stroke);
  border-radius: 999px;
}
.aa-slot .aa-placeholder .aa-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 22px;
  color: var(--text-high);
}
.aa-slot .aa-placeholder .aa-sub { font-size: 13px; color: var(--text-low); }
.aa-slot .aa-placeholder .mini-logo { color: var(--accent); width: 40px; height: 40px; }

/* hero stats row — meaningful, not filler */
.hero-meta { display: flex; gap: 24px; flex-wrap: wrap; padding-top: 8px; margin-top: 4px; }
.hero-meta .chip {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px;
  color: var(--text-mid);
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
}
.hero-meta .dot { width: 8px; height: 8px; border-radius: 50%; }

@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; gap: 32px; }
}

/* ======================================================= features ==== */

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--stroke-soft);
  border: 1px solid var(--stroke-soft);
  border-radius: 16px;
  overflow: hidden;
}
.feature {
  background: var(--bg-1);
  padding: 28px;
  display: flex; flex-direction: column; gap: 10px;
  min-height: 220px;
}
.feature .icon {
  width: 28px; height: 28px;
  color: var(--text-high);
  margin-bottom: 8px;
}
.feature h3 { color: var(--text-high); }
.feature p { color: var(--text-mid); margin: 0; font-size: 14.5px; line-height: 1.55; }

@media (max-width: 980px) { .features-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .features-grid { grid-template-columns: 1fr; } }

/* =========================================================== how ===== */

.how-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.step-card {
  background: var(--bg-1);
  border: 1px solid var(--stroke-soft);
  border-radius: 18px;
  padding: 20px;
  display: flex; flex-direction: column; gap: 14px;
}
.step-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}
.step-shot {
  aspect-ratio: 1206 / 2622;
  background: var(--bg-0);
  border: 1px solid var(--stroke-soft);
  border-radius: 28px;
  overflow: hidden;
  position: relative;
}
.step-shot img { width: 100%; height: 100%; object-fit: contain; background: var(--bg-0); }
.step-caption { color: var(--text-mid); font-size: 14px; line-height: 1.5; }

@media (max-width: 820px) { .how-strip { grid-template-columns: 1fr; } }

/* Legend */
.legend {
  display: flex; flex-wrap: wrap; gap: 24px;
  align-items: center;
  margin-top: 36px;
  padding: 18px 20px;
  background: var(--bg-1);
  border: 1px solid var(--stroke-soft);
  border-radius: 14px;
}
.legend-head {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-low);
  margin-right: 8px;
}
.legend-item { display: inline-flex; align-items: center; gap: 10px; font-size: 14px; color: var(--text-mid); }
.legend-swatch { width: 14px; height: 14px; border-radius: 3px; }
.legend-item.green .legend-swatch { background: var(--green); }
.legend-item.amber .legend-swatch { background: var(--amber); }
.legend-item.red   .legend-swatch { background: var(--red); }

/* ======================================================== screens ==== */

.screens-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.screen-card {
  background: var(--bg-1);
  border: 1px solid var(--stroke-soft);
  border-radius: 18px;
  padding: 20px;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 20px;
  align-items: center;
}
.screen-card .step-shot { aspect-ratio: 1206 / 2622; width: 100%; }
.screen-card .caption { color: var(--text-mid); font-size: 14.5px; line-height: 1.5; }
.screen-card .caption .label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-low);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  display: block;
  margin-bottom: 6px;
}

@media (max-width: 900px) { .screens-grid { grid-template-columns: 1fr; } }
@media (max-width: 480px) {
  .screen-card { grid-template-columns: 140px 1fr; gap: 16px; padding: 16px; }
}

/* ========================================================= privacy ==== */

.privacy {
  background: var(--bg-1);
  border-top: 1px solid var(--stroke-soft);
  border-bottom: 1px solid var(--stroke-soft);
}
.privacy-list {
  list-style: none;
  padding: 0;
  margin: 0 0 24px 0;
  display: grid;
  gap: 14px;
}
.privacy-list li {
  display: flex; gap: 14px;
  padding: 16px 18px;
  background: var(--bg-0);
  border: 1px solid var(--stroke-soft);
  border-radius: 12px;
  color: var(--text-high);
  font-size: 15.5px;
}
.privacy-list .tick {
  flex: 0 0 auto;
  width: 22px; height: 22px;
  color: var(--accent);
}
.privacy-foot {
  color: var(--text-mid);
  font-size: 14.5px;
  display: flex; flex-wrap: wrap; gap: 12px; align-items: center;
}
.mit-badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 10px;
  border: 1px solid var(--stroke);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-high);
}
.mit-badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }

.privacy-foot a { color: var(--accent); }
.privacy-foot a:hover { text-decoration: underline; }

/* ========================================================= download === */

.download-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 18px;
}
.dl-card {
  background: var(--bg-1);
  border: 1px solid var(--stroke-soft);
  border-radius: 18px;
  padding: 24px;
  display: flex; flex-direction: column; gap: 12px;
  transition: transform 240ms ease, border-color 240ms ease;
  color: var(--text-high);
}
.dl-card:hover { border-color: var(--stroke); color: var(--text-high); }
@media (prefers-reduced-motion: no-preference) {
  .dl-card:hover { transform: translateY(-3px); }
}
.dl-card .mark { width: 32px; height: 32px; color: var(--accent); }
.dl-card h3 { font-size: 18px; color: var(--text-high); }
.dl-card p { margin: 0; color: var(--text-mid); font-size: 14px; line-height: 1.5; }
.dl-card .open-link {
  margin-top: auto;
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--accent);
  font-size: 13px;
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding-top: 10px;
}
.dl-card .open-link svg { width: 12px; height: 12px; }

.dl-card details {
  border-top: 1px dashed var(--stroke-soft);
  padding-top: 12px;
  margin-top: 4px;
}
.dl-card details summary {
  cursor: pointer;
  font-size: 13px;
  color: var(--text-mid);
  list-style: none;
  display: inline-flex; align-items: center; gap: 6px;
}
.dl-card details summary::-webkit-details-marker { display: none; }
.dl-card details summary::before {
  content: "+";
  font-family: var(--font-mono);
  color: var(--accent);
}
.dl-card details[open] summary::before { content: "−"; }
.dl-card details ol {
  margin: 10px 0 0 0;
  padding-left: 18px;
  color: var(--text-mid);
  font-size: 13px;
  display: grid; gap: 6px;
}

@media (max-width: 980px) { .download-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .download-grid { grid-template-columns: 1fr; } }

/* ========================================================= footer ==== */

.site-footer {
  padding: 40px 0 56px;
  color: var(--text-low);
  font-size: 13px;
  border-top: 1px solid var(--stroke-soft);
}
.foot-row {
  display: flex; flex-wrap: wrap; gap: 16px;
  align-items: center;
}
.foot-row + .foot-row { margin-top: 14px; }
.foot-row .spacer { flex: 1; }
.site-footer .lang-pill { flex: 0 0 auto; }
.site-footer p { margin: 0; }

/* ===================================================== screenshot SS == */
/* Generic phone-shot card used inside step-shot and screen-card */
.ss-fallback {
  width: 100%; height: 100%;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 10px;
  background: var(--bg-0);
  color: var(--text-low);
  padding: 16px;
  text-align: center;
}
.ss-fallback svg { width: 36px; height: 36px; color: var(--accent); }
.ss-fallback .ss-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

/* =========================================== language-change fade ==== */
@keyframes i18nFade {
  0% { opacity: 0.2; }
  100% { opacity: 1; }
}
.i18n-swap [data-i18n], .i18n-swap [data-i18n-alt], .i18n-swap [data-i18n-aria-label] {
  animation: i18nFade 180ms ease-out;
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  .dl-card:hover { transform: none; }
}