/* ============================================================
   RANGE CALENDAR — Interactive date-range picker for check-in /
   check-out and any two-date selection flow.

   Shows a dual-month grid (single-column on mobile) with
   navigation arrows, weekday headers, and day cells.
   Selected range = start + end anchors with in-range fill.

   Primitive #29 — RangeCalendar

   USAGE:
   <div class="range-calendar">
     <div class="range-calendar__nav">
       <button class="range-calendar__nav-btn" aria-label="Previous month">
         <svg><use href="#icon-chevron-left"/></svg>
       </button>
       <div class="range-calendar__nav-title">April 2026 — May 2026</div>
       <button class="range-calendar__nav-btn" aria-label="Next month">
         <svg><use href="#icon-chevron-right"/></svg>
       </button>
     </div>
     <div class="range-calendar__months">
       <!-- Each month block -->
       <div>
         <div class="range-calendar__month-title">April 2026</div>
         <div class="range-calendar__weekdays">
           <span class="range-calendar__weekday">Sun</span>
           ...
         </div>
         <div class="range-calendar__days">
           <div class="range-calendar__day">1</div>
           <div class="range-calendar__day--start">9</div>
           <div class="range-calendar__day--in-range">10</div>
           <div class="range-calendar__day--end">12</div>
           <div class="range-calendar__day--disabled">30</div>
           ...
         </div>
       </div>
     </div>
   </div>

   STATES:
   --start       Start anchor (check-in). Primary background.
   --end         End anchor (check-out). Primary background.
   --in-range    Days between start and end. Secondary fill.
   --today       Current day. Bold weight, no background shift.
   --disabled    Past dates or out-of-bounds. Muted, no pointer.
   --empty       Grid padding cells. Invisible, no interaction.

   TOKENS CONSUMED:
   --color-primary, --color-secondary, --color-on-primary
   --color-text-primary, --color-text-secondary
   --color-border, --color-accent
   --color-surface-warm
   --font-display, --font-body
   ============================================================ */

/* ── Container ─────────────────────────────────────────────── */

.range-calendar {
  margin-top: 16px;
}

/* ── Navigation bar ────────────────────────────────────────── */

.range-calendar__nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.range-calendar__nav-btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: border-color 0.2s ease;
}

.range-calendar__nav-btn:hover {
  border-color: var(--color-accent);
}

.range-calendar__nav-btn svg {
  width: 16px;
  height: 16px;
  color: var(--color-text-primary);
}

.range-calendar__nav-title {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-primary);
}

/* ── Month grid ────────────────────────────────────────────── */

.range-calendar__months {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.range-calendar__month-title {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text-primary);
  text-align: center;
  margin-bottom: 8px;
}

/* ── Weekday headers ───────────────────────────────────────── */

.range-calendar__weekdays {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  text-align: center;
  margin-bottom: 4px;
}

.range-calendar__weekday {
  font-family: var(--font-body);
  font-size: 10px;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 4px 0;
}

/* ── Day cells ─────────────────────────────────────────────── */

.range-calendar__days {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  text-align: center;
}

.range-calendar__day {
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--color-text-primary);
  padding: 8px 2px;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
  position: relative;
}

.range-calendar__day:hover {
  background: var(--color-surface-warm);
}

/* ── Day states ────────────────────────────────────────────── */

.range-calendar__day--empty {
  cursor: default;
}

.range-calendar__day--disabled {
  color: var(--color-border);
  cursor: not-allowed;
}

.range-calendar__day--disabled:hover {
  background: none;
}

.range-calendar__day--today {
  font-weight: 600;
}

.range-calendar__day--start,
.range-calendar__day--end {
  background: var(--color-primary);
  color: var(--color-on-primary);
  font-weight: 600;
}

.range-calendar__day--start:hover,
.range-calendar__day--end:hover {
  background: var(--color-secondary);
  color: var(--color-on-primary);
}

.range-calendar__day--in-range {
  background: var(--color-secondary);
  color: var(--color-on-primary);
  font-weight: 500;
}

/* ── Responsive ────────────────────────────────────────────── */

@media (max-width: 767px) {
  .range-calendar__months {
    grid-template-columns: 1fr;
    gap: 16px;
  }
}