:root {
  color-scheme: light;
  --bg: #f4f7fb;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #14213d;
  --muted: #61708a;
  --accent: #2f73ff;
  --accent-soft: #e8f0ff;
  --warning: #b45309;
  --danger: #b91c1c;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.5;
}

.app-shell { max-width: 1100px; margin: 0 auto; padding: 24px; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: 0 12px 38px rgba(20, 33, 61, 0.06);
  padding: 24px;
  margin-bottom: 20px;
}
.hero-card { padding: 28px; }
.hero-head { display: flex; justify-content: space-between; gap: 16px; align-items: flex-start; margin-bottom: 20px; }
.eyebrow { margin: 0 0 6px; color: var(--accent); font-weight: 700; text-transform: uppercase; letter-spacing: 0.12em; font-size: 0.8rem; }
h1 { margin: 0; font-size: clamp(1.5rem, 2.4vw, 2.2rem); }
.hero-copy { max-width: 540px; color: var(--muted); margin: 0; }
.tabs { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 20px; }
.tab { border: 1px solid var(--border); border-radius: 999px; padding: 10px 14px; background: var(--surface); cursor: pointer; font-weight: 600; color: var(--muted); }
.tab.is-active { background: var(--accent); color: white; border-color: var(--accent); }
.settings-card h2, .custom-holidays-card h2 { margin-top: 0; font-size: 1rem; }
.settings-grid, .form-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.field { display: flex; flex-direction: column; gap: 8px; font-weight: 600; }
.field span { font-size: 0.95rem; color: var(--muted); }
input, select, button { font: inherit; }
input, select {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  background: white;
  color: var(--text);
}
input:focus, select:focus, button:focus { outline: 2px solid var(--accent-soft); outline-offset: 2px; }
/* collapsible custom holidays */
.collapsible-toggle {
  background: none;
  border: 1px dashed var(--border);
  border-radius: 10px;
  width: 100%;
  text-align: left;
  padding: 10px 14px;
  cursor: pointer;
  color: var(--accent);
  font-weight: 600;
}
.collapsible-toggle:hover { background: var(--accent-soft); }
.collapsible-body { margin-top: 14px; }
.custom-holiday-form { display: grid; grid-template-columns: 1fr 1fr auto; gap: 10px; align-items: end; }

/* result card */
.result-card { display: grid; gap: 10px; }
.result-hero { display: flex; align-items: baseline; gap: 10px; }
.result-number { font-size: clamp(2.4rem, 4vw, 3.4rem); font-weight: 800; color: var(--accent); line-height: 1; }
.result-label { font-size: 1rem; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: 0.06em; }
.result-dates { color: var(--muted); margin: 0; font-size: 0.95rem; }
.result-summary { display: grid; gap: 8px; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); }
.summary-item { border: 1px solid var(--border); border-radius: 10px; padding: 10px 12px; background: #fbfdff; }
.summary-item strong { display: block; font-size: 1.05rem; }
.summary-item span { font-size: 0.82rem; color: var(--muted); }

/* holiday breakdown */
.holiday-breakdown { margin: 0; padding: 0; list-style: none; display: grid; gap: 6px; }
.holiday-breakdown li { font-size: 0.9rem; display: flex; justify-content: space-between; align-items: baseline; gap: 8px; }
.holiday-name { font-weight: 600; }
.holiday-effect { font-size: 0.8rem; color: var(--muted); white-space: nowrap; }
.holiday-effect.affects { color: var(--warning); }
.breakdown-heading { font-size: 0.8rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); margin: 6px 0 4px; }

/* weekday buttons */
.weekday-buttons { display: flex; flex-wrap: nowrap; gap: 5px; }
.weekday-btn {
  border: 1px solid var(--border);
  background: #f8fafc;
  border-radius: 999px;
  padding: 6px 0;
  cursor: pointer;
  width: 34px;
  text-align: center;
  font-weight: 600;
  color: var(--muted);
  font-size: 0.85rem;
  flex-shrink: 0;
}
.weekday-btn.is-active { background: var(--accent); color: white; border-color: var(--accent); }

/* calendar multi-column grid */
.calendar-toggle-btn {
  background: var(--accent-soft);
  border: none;
  border-radius: 999px;
  padding: 9px 18px;
  cursor: pointer;
  color: var(--accent);
  font-weight: 700;
  font-size: 0.92rem;
}
.calendar-months-wrap.is-hidden { display: none !important; }
.calendar-grid {
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
@media (max-width: 960px) {
  .calendar-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 580px) {
  .calendar-grid { grid-template-columns: 1fr; }
  .weekday-buttons { flex-wrap: wrap; }
}
.calendar-month { border: 1px solid var(--border); border-radius: 10px; padding: 8px; }
.calendar-header { font-weight: 700; font-size: 0.85rem; margin-bottom: 6px; }
.calendar-weekdays, .calendar-dates { display: grid; grid-template-columns: repeat(7, minmax(0, 1fr)); gap: 2px; }
.calendar-weekday { text-align: center; padding: 3px 0; font-size: 0.72rem; color: var(--muted); font-weight: 600; }
.calendar-day { border-radius: 4px; min-height: 26px; font-size: 0.78rem; display: flex; align-items: center; justify-content: center; border: 1px solid transparent; }

.calculator-form.is-hidden { display: none; }
.inline-options, .mode-toggle { display: flex; gap: 16px; flex-wrap: wrap; color: var(--muted); }
.quick-buttons, .payment-shortcuts { display: flex; flex-wrap: wrap; gap: 8px; }
.quick-btn, .payment-btn, .secondary-btn, .primary-btn, .copy-btn {
  border: none;
  border-radius: 999px;
  padding: 10px 14px;
  cursor: pointer;
  font-weight: 700;
}
.primary-btn { background: var(--accent); color: white; }
.secondary-btn, .copy-btn { background: var(--accent-soft); color: var(--accent); }
.message { min-height: 24px; color: var(--danger); font-weight: 600; }
.message.success { color: var(--accent); }
.custom-holiday-list { list-style: none; padding: 0; display: grid; gap: 8px; margin: 12px 0 0; }
.custom-holiday-list li { display: flex; justify-content: space-between; align-items: center; gap: 10px; border: 1px solid var(--border); border-radius: 10px; padding: 10px 12px; }
.remove-btn { border: none; background: transparent; color: var(--danger); cursor: pointer; font-weight: 700; }
.calendar-card { display: grid; gap: 10px; }
.calendar-day.is-outside { color: #c0c8d4; background: none; }
.calendar-day.is-working { background: #f8fafc; }
.calendar-day.is-non-working { background: #f4f7fb; color: #64748b; }
.calendar-day.is-public-holiday { background: #fff7ed; color: #9a2c2c; border-color: #fed7aa; }
.calendar-day.is-custom-holiday { background: #fdf2f8; color: #be185d; border-color: #fbcfe8; }
.calendar-day.is-selected { background: var(--accent-soft); color: var(--accent); border-color: var(--accent); }
.calendar-day.is-start { box-shadow: inset 0 0 0 2px var(--accent); }
.calendar-day.is-deadline { box-shadow: inset 0 0 0 2px #0f766e; }
.legend { display: flex; flex-wrap: wrap; gap: 10px; color: var(--muted); font-size: 0.88rem; }
.legend span { display: inline-flex; align-items: center; gap: 5px; }
.legend .dot { width: 9px; height: 9px; border-radius: 999px; display: inline-block; background: var(--accent); }
.legend .dot.non-working { background: #64748b; }
.legend .dot.public-holiday { background: #b45309; }
.legend .dot.custom-holiday { background: #be185d; }
.is-hidden { display: none !important; }
.section-divider { border: none; border-top: 1px solid var(--border); margin: 20px 0 16px; }
.section-heading { margin: 0 0 4px; font-size: 0.95rem; font-weight: 700; }
.section-note { margin: 0 0 12px; font-size: 0.85rem; color: var(--muted); }
@media (max-width: 780px) {
  .app-shell { padding: 16px; }
  .hero-head { flex-direction: column; }
  .settings-grid, .form-grid { grid-template-columns: 1fr; }
  .card { padding: 18px; }
}