/* Buffo shared web tokens — dark / light */
:root,
html[data-theme='dark'] {
  --b-bg0: #05080a;
  --b-bg1: #0b1519;
  --b-card: rgba(15, 23, 42, 0.62);
  --b-card-solid: #141a1c;
  --b-border: rgba(255, 255, 255, 0.1);
  --b-border-accent: rgba(66, 136, 137, 0.28);
  --b-text: #edf2f1;
  --b-muted: #9aabaf;
  --b-teal: #166b6d;
  --b-tealb: #428889;
  --b-emerald: #2e7d4f;
  --b-amber: #b45309;
  --b-header: rgba(8, 14, 16, 0.72);
  --b-chip: rgba(255, 255, 255, 0.06);
  --b-chip-active: rgba(66, 136, 137, 0.35);
  --b-shadow: 0 16px 48px rgba(0, 0, 0, 0.4);
  --b-gradient: radial-gradient(ellipse 90% 70% at 50% 30%, var(--b-bg1) 0%, var(--b-bg0) 68%);
}

html[data-theme='light'] {
  --b-bg0: #e9eceb;
  --b-bg1: #f4f7f6;
  --b-card: rgba(255, 255, 255, 0.68);
  --b-card-solid: #ffffff;
  --b-border: rgba(15, 23, 42, 0.08);
  --b-border-accent: rgba(22, 107, 109, 0.22);
  --b-text: #152426;
  --b-muted: #5a6a6e;
  --b-teal: #166b6d;
  --b-tealb: #2a8a8c;
  --b-emerald: #3d9b6a;
  --b-amber: #c47a1a;
  --b-header: rgba(255, 255, 255, 0.78);
  --b-chip: rgba(15, 23, 42, 0.05);
  --b-chip-active: rgba(22, 107, 109, 0.18);
  --b-shadow: 0 16px 40px rgba(21, 36, 38, 0.1);
  --b-gradient: radial-gradient(ellipse 90% 70% at 50% 25%, #ffffff 0%, var(--b-bg1) 45%, var(--b-bg0) 100%);
}

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

html {
  scroll-behavior: auto;
  color-scheme: dark;
}
html[data-theme='light'] { color-scheme: light; }

body {
  margin: 0;
  min-height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Segoe UI', Inter, Roboto, Helvetica, Arial, sans-serif;
  color: var(--b-text);
  background: var(--b-gradient);
  -webkit-font-smoothing: antialiased;
  transition: background 0.35s ease, color 0.25s ease;
}

/* ── Universal sticky header ── */
#buffo-header-root {
  position: sticky;
  top: 0;
  z-index: 100;
}

.buffo-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 16px;
  padding-top: max(10px, env(safe-area-inset-top));
  background: var(--b-header);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--b-border);
  transition: background 0.3s ease, border-color 0.3s ease;
}

.buffo-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--b-text);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.buffo-logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 9px;
  display: grid;
  place-items: center;
  font-size: 0.95rem;
  color: #fff;
  background: linear-gradient(145deg, var(--b-teal), var(--b-tealb));
  box-shadow: 0 4px 14px rgba(22, 107, 109, 0.35);
}

.buffo-logo-text { font-size: 1.1rem; }

.buffo-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.buffo-lang {
  display: inline-flex;
  gap: 2px;
  padding: 3px;
  border-radius: 999px;
  background: var(--b-chip);
  border: 1px solid var(--b-border);
}

.buffo-chip {
  appearance: none;
  border: 0;
  background: transparent;
  color: var(--b-muted);
  font: inherit;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 7px 11px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.buffo-chip:hover { color: var(--b-text); }
.buffo-chip.is-active {
  background: var(--b-chip-active);
  color: var(--b-text);
}

.buffo-theme {
  width: 40px;
  height: 36px;
  padding: 0;
  display: grid;
  place-items: center;
  background: var(--b-chip);
  border: 1px solid var(--b-border);
  font-size: 1rem;
}

/* Glass cards */
.b-card {
  background: var(--b-card);
  border: 1px solid var(--b-border-accent);
  border-radius: 22px;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--b-shadow);
  transition: background 0.3s ease, border-color 0.3s ease, color 0.25s ease;
}

.b-muted { color: var(--b-muted); }
.b-teal { color: var(--b-tealb); }

.b-btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  padding: 14px 18px;
  border: 0;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--b-teal), var(--b-tealb));
  color: #fff !important;
  font-weight: 750;
  font-size: 1rem;
  text-decoration: none;
  cursor: pointer;
  box-shadow: 0 10px 28px rgba(22, 107, 109, 0.35);
  transition: transform 0.15s ease, box-shadow 0.2s ease;
}

.b-btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 32px rgba(22, 107, 109, 0.45);
}

.b-store {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 12px;
  border-radius: 14px;
  background: var(--b-chip);
  border: 1px solid var(--b-border);
  color: var(--b-text);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 650;
  transition: border-color 0.15s ease;
}

.b-store:hover { border-color: var(--b-tealb); }

/* Modal gate */
.b-overlay {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: none;
  align-items: flex-end;
  justify-content: center;
  padding: 16px;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(6px);
}

html[data-theme='light'] .b-overlay {
  background: rgba(21, 36, 38, 0.35);
}

.b-overlay.open { display: flex; }

.b-modal {
  width: min(420px, 100%);
  background: var(--b-card-solid);
  border: 1px solid var(--b-border-accent);
  border-radius: 24px;
  padding: 22px 20px;
  box-shadow: var(--b-shadow);
  animation: b-pop 0.28s cubic-bezier(0.2, 0.9, 0.3, 1);
}

@keyframes b-pop {
  from { transform: translateY(20px) scale(0.97); opacity: 0; }
  to { transform: translateY(0) scale(1); opacity: 1; }
}

.b-modal h3 { margin: 0 0 8px; font-size: 1.2rem; }
.b-modal p { margin: 0 0 16px; color: var(--b-muted); line-height: 1.45; }
.b-modal .b-close {
  display: block;
  width: 100%;
  margin-top: 10px;
  background: transparent;
  border: 0;
  color: var(--b-muted);
  padding: 10px;
  cursor: pointer;
  font: inherit;
}