:root {
  --bg: #faf6ec;
  --bg-card: #fffdf6;
  --bg-sunken: #f2ecdc;
  --ink: #1a1a1a;
  --ink-soft: #5c5347;
  --ink-faint: #9a9080;
  --line: #e4ddcb;
  --accent: #2563eb;
  --warn: #c85c2f;
  --ok: #2f7d3e;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
body {
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  overscroll-behavior-y: none;
}
.bbn-app { max-width: 720px; margin: 0 auto; min-height: 100vh; }

.bbn-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 12px;
}

.bbn-label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  color: var(--ink-soft);
  letterspacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 6px;
}

.bbn-input {
  width: 100%;
  font: inherit;
  padding: 12px 14px;
  background: var(--bg-card);
  border: 1.5px solid var(--line);
  border-radius: 10px;
  color: var(--ink);
  outline: none;
  transition: border-color 0.15s;
  font-size: 16px;
}
.bbn-input:focus { border-color: var(--accent); }
.bbn-input:disabled { background: var(--bg-sunken); color: var(--ink-faint); }

.bbn-btn {
  font: inherit;
  padding: 12px 18px;
  border: none;
  border-radius: 10px;
  background: var(--ink);
  color: var(--bg-card);
  cursor: pointer;
  font-weight: 500;
  font-size: 15px;
  transition: opacity 0.15s;
}
.bbn-btn:disabled { opacity: 0.45; cursor: not-allowed; }

.bbn-view { padding: 0; }
.bbn-toast {
  position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%);
  background: var(--ink); color: var(--bg-card); padding: 12px 20px;
  border-radius: 10px; font-size: 14px; z-index: 100;
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
}

.bbn-mono { font-family: ui-monospace, "SF Mono", Consolas, monospace; }

/* Sticky bottom action bar */
.bbn-sticky-bottom {
  position: sticky; bottom: 0; left: 0; right: 0;
  background: rgba(250,246,236,0.95);
  backdrop-filter: blur(12px);
  border-top: 1px solid var(--line);
  padding: 14px 18px;
  margin: 24px -18px 0;
}