/* ==========================================================================
   Business AI — app-shell design system
   Light, warm-paper surface for long-session product use (dashboard, chat,
   auth). The marketing site (index.html) uses its own dark stylesheet —
   two deliberate surfaces for two different jobs, one shared brand.
   ========================================================================== */

:root {
  /* Brand */
  --ba-primary: #D63C47;
  --ba-primary-strong: #B02A36;
  --ba-primary-soft: #FFE9DF;
  --ba-accent: #FF8A3D;

  /* Surfaces */
  --ba-bg: #FFF8F2;
  --ba-surface: #FFFFFF;
  --ba-surface-2: #FFFBF7;
  --ba-surface-sunken: #FFF0E6;

  /* Ink */
  --ba-ink: #23253A;
  --ba-ink-soft: #3A3D5C;
  --ba-muted: #6B6478;
  --ba-faint: #97998f;

  /* Lines */
  --ba-border: #F1E0D4;
  --ba-border-strong: #E6CBBB;

  /* Semantic */
  --ba-warn-bg: #FDF6E4;
  --ba-warn-border: #EFD98F;
  --ba-warn-text: #6B5217;
  --ba-error-bg: #FCEEEC;
  --ba-error-border: #EFC3BC;
  --ba-error-text: #8A2E22;
  --ba-info-bg: #EAF2F6;
  --ba-info-border: #C3DCE6;
  --ba-info-text: #234A5C;
  --ba-good-bg: #E9F5EC;
  --ba-good-border: #B9DDC3;
  --ba-good-text: #1F6B37;

  /* Geometry */
  --ba-radius-sm: 8px;
  --ba-radius: 12px;
  --ba-radius-lg: 18px;
  --ba-radius-full: 999px;

  /* Elevation */
  --ba-shadow-sm: 0 1px 2px rgba(20, 24, 22, 0.05);
  --ba-shadow-md: 0 6px 20px -4px rgba(20, 24, 22, 0.10), 0 2px 6px -2px rgba(20, 24, 22, 0.06);
  --ba-shadow-lg: 0 20px 44px -12px rgba(20, 24, 22, 0.18), 0 4px 10px -2px rgba(20, 24, 22, 0.06);

  /* Type */
  --ba-font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, "Helvetica Neue", Arial, sans-serif;
  --ba-font-serif: ui-serif, Georgia, "Iowan Old Style", "Palatino Linotype", Palatino, serif;

  font-family: var(--ba-font-sans);
  color-scheme: light;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--ba-bg);
  color: var(--ba-ink);
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: var(--ba-font-serif);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.2;
  margin: 0 0 8px;
  color: var(--ba-ink);
}
h1 { font-size: 1.75rem; }
h2 { font-size: 1.25rem; }
h3 { font-size: 1.0625rem; }
p { margin: 0 0 12px; }

a { color: var(--ba-primary); }

::selection { background: var(--ba-primary-soft); color: var(--ba-primary-strong); }

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

/* ---------------------------------------------------------------- layout */

.ba-container { max-width: 960px; margin: 0 auto; padding: 28px 24px 64px; }
.ba-narrow { max-width: 440px; margin: 0 auto; padding: 24px; }

.ba-navbar {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 24px; border-bottom: 1px solid var(--ba-border);
  background: var(--ba-surface);
  position: sticky; top: 0; z-index: 20;
}
.ba-brand {
  display: inline-flex; align-items: center; gap: 9px;
  color: var(--ba-ink); text-decoration: none; font-weight: 800; font-size: 1.0625rem;
  letter-spacing: .04em; text-transform: uppercase;
}
.ba-navbar a.ba-navlink { color: var(--ba-ink-soft); text-decoration: none; font-weight: 600; font-size: 0.875rem; }
.ba-navbar a.ba-navlink:hover { color: var(--ba-ink); }

/* ------------------------------------------------------------------ card */

.ba-card {
  background: var(--ba-surface); border: 1px solid var(--ba-border); border-radius: var(--ba-radius);
  padding: 22px; margin-bottom: 16px; box-shadow: var(--ba-shadow-sm);
}
.ba-card-title-row { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; }

/* --------------------------------------------------------------- button */

.ba-btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 18px; border-radius: var(--ba-radius-sm);
  border: 1px solid var(--ba-primary); background: var(--ba-primary); color: #fff;
  font-weight: 600; cursor: pointer; text-decoration: none; font-size: 0.875rem;
  font-family: var(--ba-font-sans);
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease;
}
.ba-btn:hover { background: var(--ba-primary-strong); border-color: var(--ba-primary-strong); }
.ba-btn:active { transform: translateY(1px); }
.ba-btn-secondary { background: transparent; color: var(--ba-primary); border-color: var(--ba-border-strong); }
.ba-btn-secondary:hover { background: var(--ba-primary-soft); border-color: var(--ba-primary); }
.ba-btn-ghost { background: transparent; color: var(--ba-ink-soft); border-color: transparent; }
.ba-btn-ghost:hover { background: var(--ba-surface-sunken); color: var(--ba-ink); }
.ba-btn-danger { background: #fff; color: var(--ba-error-text); border-color: var(--ba-error-border); }
.ba-btn-danger:hover { background: var(--ba-error-bg); }
.ba-btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.ba-btn-block { width: 100%; }
.ba-btn-sm { padding: 6px 12px; font-size: 0.8125rem; }

/* ---------------------------------------------------------------- forms */

.ba-input, textarea.ba-input {
  width: 100%; padding: 10px 13px; border: 1px solid var(--ba-border-strong);
  border-radius: var(--ba-radius-sm); font-size: 0.9375rem; font-family: inherit;
  background: var(--ba-surface); color: var(--ba-ink);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.ba-input:focus {
  outline: none; border-color: var(--ba-accent);
  box-shadow: 0 0 0 3px rgba(214, 60, 71, 0.18);
}
.ba-label { display: block; font-size: 0.75rem; font-weight: 700; letter-spacing: 0.01em; margin-bottom: 6px; color: var(--ba-ink-soft); text-transform: uppercase; }
.ba-field { margin-bottom: 16px; }
.ba-hint { font-size: 0.8125rem; color: var(--ba-muted); margin-top: -10px; margin-bottom: 14px; }

.ba-password-field { position: relative; }
.ba-password-field .ba-input { padding-right: 42px; }
.ba-password-toggle {
  position: absolute; top: 50%; right: 4px; transform: translateY(-50%);
  width: 32px; height: 32px; display: flex; align-items: center; justify-content: center;
  background: none; border: none; cursor: pointer; color: var(--ba-muted); border-radius: var(--ba-radius-sm);
  padding: 0;
}
.ba-password-toggle:hover { color: var(--ba-ink-soft); background: var(--ba-surface-sunken); }
.ba-password-toggle svg { width: 18px; height: 18px; }
.ba-password-toggle .eye-off { display: none; }
.ba-password-toggle.showing .eye { display: none; }
.ba-password-toggle.showing .eye-off { display: block; }

/* --------------------------------------------------------------- alerts */

.ba-alert {
  padding: 12px 14px; border-radius: var(--ba-radius-sm); font-size: 0.875rem; margin-bottom: 14px;
  display: flex; gap: 10px; align-items: flex-start;
}
.ba-alert-error { background: var(--ba-error-bg); border: 1px solid var(--ba-error-border); color: var(--ba-error-text); }
.ba-alert-warn { background: var(--ba-warn-bg); border: 1px solid var(--ba-warn-border); color: var(--ba-warn-text); }
.ba-alert-info { background: var(--ba-info-bg); border: 1px solid var(--ba-info-border); color: var(--ba-info-text); }

/* ---------------------------------------------------------------- badge */

.ba-badge {
  display: inline-flex; align-items: center; gap: 5px; padding: 3px 10px;
  border-radius: var(--ba-radius-full); font-size: 0.6875rem; font-weight: 700;
  letter-spacing: 0.03em; text-transform: uppercase; line-height: 1.6;
}
.ba-badge-primary { background: var(--ba-primary-soft); color: var(--ba-primary-strong); }
.ba-badge-good { background: var(--ba-good-bg); color: var(--ba-good-text); border: 1px solid var(--ba-good-border); }
.ba-badge-warn { background: var(--ba-warn-bg); color: var(--ba-warn-text); border: 1px solid var(--ba-warn-border); }
.ba-badge-error { background: var(--ba-error-bg); color: var(--ba-error-text); border: 1px solid var(--ba-error-border); }
.ba-badge-neutral { background: var(--ba-surface-sunken); color: var(--ba-ink-soft); }
.ba-badge-dot { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }

/* ----------------------------------------------------------------- tabs */

.ba-tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--ba-border); margin-bottom: 22px; }
.ba-tab { padding: 10px 4px; margin-right: 20px; cursor: pointer; border-bottom: 2px solid transparent; font-weight: 600; color: var(--ba-muted); font-size: 0.9375rem; transition: color 0.15s ease; }
.ba-tab.active { color: var(--ba-primary); border-bottom-color: var(--ba-primary); }
.ba-tab-panel { display: none; animation: ba-fade-in 0.2s ease; }
.ba-tab-panel.active { display: block; }

/* ----------------------------------------------------------------- chat */

.ba-chat-thread { display: flex; flex-direction: column; gap: 12px; padding: 18px 4px; min-height: 280px; overflow-y: auto; }
.ba-msg-user, .ba-msg-assistant {
  padding: 11px 15px; max-width: 78%; font-size: 0.9375rem; line-height: 1.45;
  animation: ba-msg-in 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}
.ba-msg-user { align-self: flex-end; background: var(--ba-primary); color: #fff; border-radius: 16px 16px 3px 16px; }
.ba-msg-assistant { align-self: flex-start; background: var(--ba-surface); border: 1px solid var(--ba-border); border-radius: 16px 16px 16px 3px; box-shadow: var(--ba-shadow-sm); }
.ba-chat-input-row { display: flex; gap: 8px; padding: 14px 0 2px; border-top: 1px solid var(--ba-border); }
.ba-typing { display: inline-flex; gap: 4px; padding: 4px 2px; }
.ba-typing span { width: 6px; height: 6px; border-radius: 50%; background: var(--ba-faint); animation: ba-typing-bounce 1.1s infinite ease-in-out; }
.ba-typing span:nth-child(2) { animation-delay: 0.15s; }
.ba-typing span:nth-child(3) { animation-delay: 0.3s; }

/* ---------------------------------------------------------------- stats */

.ba-muted { color: var(--ba-muted); font-size: 0.875rem; }
.ba-metric { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 12px; margin-bottom: 16px; }
.ba-metric-box { background: var(--ba-surface); border: 1px solid var(--ba-border); border-radius: var(--ba-radius); padding: 16px 18px; }
.ba-metric-val { font-family: var(--ba-font-serif); font-size: 1.875rem; font-weight: 600; line-height: 1.1; margin-top: 2px; }
.ba-metric-label { font-size: 0.75rem; color: var(--ba-muted); font-weight: 600; letter-spacing: 0.02em; text-transform: uppercase; }

table.ba-table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
table.ba-table th { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--ba-border); color: var(--ba-muted); font-weight: 600; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.02em; }
table.ba-table td { text-align: left; padding: 11px 10px; border-bottom: 1px solid var(--ba-border); vertical-align: middle; }
table.ba-table tbody tr:hover { background: var(--ba-surface-2); }

/* ------------------------------------------------------------- utility */

.ba-flex { display: flex; align-items: center; gap: 10px; }
.ba-icon { width: 18px; height: 18px; flex-shrink: 0; display: inline-block; vertical-align: middle; }
.ba-skeleton { background: linear-gradient(90deg, var(--ba-surface-sunken) 25%, var(--ba-border) 37%, var(--ba-surface-sunken) 63%); background-size: 400% 100%; animation: ba-shimmer 1.4s ease infinite; border-radius: var(--ba-radius-sm); }

@keyframes ba-fade-in { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }
@keyframes ba-msg-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@keyframes ba-typing-bounce { 0%, 60%, 100% { transform: translateY(0); opacity: 0.5; } 30% { transform: translateY(-4px); opacity: 1; } }
@keyframes ba-shimmer { 0% { background-position: 100% 0; } 100% { background-position: 0 0; } }

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

@media (max-width: 640px) {
  .ba-container { padding: 20px 16px 48px; }
  h1 { font-size: 1.5rem; }
  .ba-metric { grid-template-columns: repeat(2, 1fr); }
}