/*
 * Payas Reckoner Calculator — App Styles (Payas Design System)
 * Part of Payas Webkit · Developer: Saman Udayanga Wijesinghe
 * Copyright (C) 2025 Saman Udayanga Wijesinghe — GPLv2
 */

/* ═══════════════════════════════════════════
   TITLE BAR  (matches Payas Editor two-row pattern)
═══════════════════════════════════════════ */
.titlebar {
  background: var(--bg-bar);
  border-bottom: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  box-shadow: var(--shadow);
  z-index: 300;
  position: relative;
}

/* Row 1 — Brand + nav actions */
.tbar-row-1 {
  display: flex; align-items: center;
  padding: 0 10px; gap: 1px; height: 40px;
  border-bottom: 1px solid var(--border);
}

/* Row 2 — Mode tabs */
.tbar-row-2 {
  display: flex; align-items: center;
  padding: 0 8px; gap: 1px; height: 36px;
  background: var(--bg-sidebar);
  overflow-x: auto; scrollbar-width: none;
}
.tbar-row-2::-webkit-scrollbar { display: none; }

.tbar-spacer { flex: 1; }

/* App logo — matches Payas pattern */
.app-logo {
  font-family: 'Fraunces', Georgia, serif;
  font-size: 15px; font-weight: 600;
  color: var(--accent); letter-spacing: -.3px;
  margin-right: 6px; user-select: none; white-space: nowrap;
  display: flex; align-items: center; gap: 6px;
}
.app-logo em { font-style: italic; font-weight: 400; font-size: 11px; color: var(--text-3); }

/* Standard title-bar button (mbar-btn) */
.mbar-btn {
  height: 28px; padding: 0 9px;
  font-family: 'DM Sans', sans-serif; font-size: 12.5px;
  color: var(--text-2); background: none; border: none;
  border-radius: 5px; cursor: pointer;
  display: flex; align-items: center; gap: 4px;
  transition: background .13s, color .13s; white-space: nowrap;
  flex-shrink: 0;
}
.mbar-btn:hover { background: var(--bg-hover); color: var(--text-1); }
.mbar-btn.active { background: var(--accent-dim); color: var(--accent); }

/* Icon-only nav button */
.mbar-icon-btn {
  width: 30px; height: 30px; padding: 0;
  display: flex; align-items: center; justify-content: center;
  background: none; border: none; border-radius: 5px;
  color: var(--text-2); cursor: pointer; font-size: 16px;
  transition: background .13s, color .13s; flex-shrink: 0;
}
.mbar-icon-btn:hover { background: var(--bg-hover); color: var(--text-1); }
.mbar-icon-btn.active { color: var(--accent); background: var(--accent-dim); }

.mbar-sep { width: 1px; height: 18px; background: var(--border); margin: 0 4px; flex-shrink: 0; }

/* Mode tab in tbar-row-2 */
.mode-tab {
  height: 28px; padding: 0 10px;
  font-family: 'DM Sans', sans-serif; font-size: 12px; font-weight: 500;
  color: var(--text-3); background: none; border: none;
  border-radius: 5px; cursor: pointer;
  display: flex; align-items: center; gap: 5px;
  transition: background .13s, color .13s; white-space: nowrap; flex-shrink: 0;
}
.mode-tab:hover { background: var(--bg-active); color: var(--text-1); }
.mode-tab.active {
  background: var(--accent-dim); color: var(--accent);
  font-weight: 600;
}
.mode-tab i { font-size: 14px; }

/* Hamburger — shown only on mobile */
.ham-btn {
  display: none;
  width: 30px; height: 30px; padding: 0;
  align-items: center; justify-content: center;
  background: none; border: none; border-radius: 5px;
  color: var(--text-2); cursor: pointer; font-size: 16px;
  transition: background .13s, color .13s; flex-shrink: 0;
}
.ham-btn:hover { background: var(--bg-hover); color: var(--text-1); }

/* fname-badge style for version badge */
.version-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px; color: var(--text-3);
  background: var(--bg-chip); border: 1px solid var(--border);
  border-radius: 20px; padding: 2px 9px;
  white-space: nowrap; flex-shrink: 0;
}

/* ═══════════════════════════════════════════
   MODE DRAWER (mobile)
═══════════════════════════════════════════ */
.drawer-overlay {
  display: none; position: fixed; inset: 0; z-index: 400;
  background: var(--overlay);
}
.drawer-overlay.open { display: block; }

.mode-drawer {
  position: fixed; left: 0; top: 0; bottom: 0; z-index: 401;
  width: 256px; background: var(--bg-bar);
  border-right: 1px solid var(--border);
  box-shadow: 4px 0 24px var(--shadow-lg);
  display: flex; flex-direction: column;
  transform: translateX(-100%);
  transition: transform .22s ease;
}
.mode-drawer.open { transform: translateX(0); }

.drawer-header {
  padding: 0 12px; height: 44px;
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  flex-shrink: 0;
}
.drawer-header .drawer-brand {
  font-family: 'Fraunces', serif; font-size: 15px;
  font-weight: 600; color: var(--accent);
}

.drawer-modes { flex: 1; overflow-y: auto; padding: 6px; }

.drawer-mode-btn {
  display: flex; align-items: center; gap: 10px;
  width: 100%; padding: 10px 12px; border-radius: 7px;
  border: none; background: none; cursor: pointer;
  font-family: 'DM Sans', sans-serif; font-size: 13px; font-weight: 500;
  color: var(--text-2); text-align: left;
  transition: background .13s, color .13s; min-height: 40px;
}
.drawer-mode-btn:hover { background: var(--bg-hover); color: var(--text-1); }
.drawer-mode-btn.active { background: var(--accent-dim); color: var(--accent); }
.drawer-mode-btn i { font-size: 17px; flex-shrink: 0; }

/* ═══════════════════════════════════════════
   MAIN LAYOUT
═══════════════════════════════════════════ */
.app-body {
  display: flex;
  flex: 1;
  overflow: hidden;
  min-height: 0;
}

.calc-main {
  flex: 1; display: flex; flex-direction: column;
  min-width: 0; overflow: hidden;
  background: var(--bg-app);
}

.calc-panel {
  flex: 1; overflow-y: auto; overflow-x: hidden;
  padding: 18px 20px;
}

/* ═══════════════════════════════════════════
   HISTORY SIDEBAR
═══════════════════════════════════════════ */
.history-panel {
  width: 272px; flex-shrink: 0;
  background: var(--bg-sidebar);
  border-left: 1px solid var(--border);
  display: flex; flex-direction: column;
  overflow: hidden;
  transition: width .22s, opacity .22s;
}
.history-panel.collapsed { width: 0; opacity: 0; pointer-events: none; }

.history-header {
  padding: 0 14px; height: 44px;
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  flex-shrink: 0;
}
.history-header h3 {
  font-family: 'Fraunces', serif; font-size: 13px;
  font-weight: 600; color: var(--text-1);
}

.history-list { flex: 1; overflow-y: auto; padding: 6px; }

.history-item {
  padding: 9px 11px; border-radius: 7px; margin-bottom: 3px;
  background: var(--bg-chip); cursor: pointer;
  transition: background .13s; border: 1px solid transparent;
}
.history-item:hover { background: var(--bg-active); border-color: var(--border); }
.history-item .h-expr {
  font-size: 11.5px; color: var(--text-3);
  font-family: 'JetBrains Mono', monospace; word-break: break-all;
}
.history-item .h-result {
  font-size: 13.5px; font-weight: 600; color: var(--accent);
  margin-top: 2px; font-family: 'JetBrains Mono', monospace;
}
.history-item .h-meta { font-size: 10px; color: var(--text-3); margin-top: 2px; }
.history-empty {
  text-align: center; padding: 32px 16px;
  color: var(--text-3); font-size: 12.5px; line-height: 1.7;
}
.history-empty i { font-size: 28px; display: block; margin-bottom: 8px; opacity: .4; }

.history-footer {
  padding: 8px 10px; border-top: 1px solid var(--border);
  display: flex; gap: 6px;
}

/* ═══════════════════════════════════════════
   CALCULATOR DISPLAY
═══════════════════════════════════════════ */
.calc-display {
  background: var(--disp-bg);
  border-radius: 12px;
  padding: 14px 18px 12px;
  margin-bottom: 14px;
  min-height: 86px;
  position: relative;
  border: 1px solid var(--border);
  transition: background .22s;
}
.calc-display .disp-mode-badge {
  position: absolute; top: 10px; left: 14px;
  font-size: 10px; font-weight: 700; letter-spacing: .06em;
  text-transform: uppercase; color: var(--text-3);
  font-family: 'DM Sans', sans-serif;
}
.calc-display .disp-expr {
  font-size: 13px; color: var(--disp-expr);
  font-family: 'JetBrains Mono', monospace;
  min-height: 18px; word-break: break-all; text-align: right;
  margin-top: 2px;
}
.calc-display .disp-result {
  font-size: 34px; font-weight: 700;
  color: var(--disp-text); text-align: right;
  font-family: 'JetBrains Mono', monospace;
  word-break: break-all; line-height: 1.2; margin-top: 2px;
}
.calc-display .disp-mem-badge {
  position: absolute; bottom: 10px; left: 14px;
  font-size: 10px; font-weight: 700; color: var(--accent);
  display: none;
}
.calc-display .disp-mem-badge.show { display: block; }

/* ═══════════════════════════════════════════
   BUTTON GRID
═══════════════════════════════════════════ */
.btn-grid { display: grid; gap: 7px; }
.btn-grid.cols-4 { grid-template-columns: repeat(4, 1fr); }
.btn-grid.cols-5 { grid-template-columns: repeat(5, 1fr); }

.calc-btn {
  height: 54px; border-radius: 8px; border: 1px solid var(--border);
  font-size: 15px; font-weight: 500;
  cursor: pointer; user-select: none;
  display: flex; align-items: center; justify-content: center;
  gap: 4px; transition: transform .08s, background .13s, box-shadow .13s;
  min-height: 44px; font-family: 'DM Sans', sans-serif;
  position: relative;
}
.calc-btn:active { transform: scale(0.95); }

/* Variants */
.calc-btn.btn-num {
  background: var(--btn-num-bg); color: var(--text-1);
  box-shadow: var(--shadow);
}
.calc-btn.btn-num:hover { background: var(--bg-hover); }

.calc-btn.btn-op {
  background: var(--btn-op-bg); color: var(--btn-op-text);
  border-color: rgba(45,106,79,.18); font-size: 18px; font-weight: 600;
}
.calc-btn.btn-op:hover { background: rgba(45,106,79,.2); }

.calc-btn.btn-fn {
  background: var(--btn-fn-bg); color: var(--btn-fn-text);
  font-size: 12.5px; border-color: var(--border);
}
.calc-btn.btn-fn:hover { background: var(--bg-hover); color: var(--text-1); }

.calc-btn.btn-clear {
  background: var(--btn-clr-bg); color: var(--btn-clr-text);
  border-color: rgba(220,38,38,.20);
}
.calc-btn.btn-clear:hover { background: rgba(220,38,38,.18); }

.calc-btn.btn-eq {
  background: var(--btn-eq-bg); color: var(--btn-eq-text);
  border-color: var(--accent-dk); font-size: 20px; font-weight: 700;
}
.calc-btn.btn-eq:hover { background: var(--accent-dk); }
[data-theme="dark"] .calc-btn.btn-eq { box-shadow: 0 0 10px rgba(82,183,136,.2); }

.calc-btn.btn-special {
  background: var(--accent-dim); color: var(--accent);
  border-color: rgba(45,106,79,.22); font-size: 12.5px;
}
.calc-btn.btn-special:hover { background: rgba(45,106,79,.22); }

.calc-btn.span2 { grid-column: span 2; }
.calc-btn.span3 { grid-column: span 3; }
.calc-btn.btn-sm { height: 42px; font-size: 12px; border-radius: 7px; }

/* ═══════════════════════════════════════════
   MEMORY BAR
═══════════════════════════════════════════ */
.mem-bar { display: flex; gap: 5px; margin-bottom: 10px; flex-wrap: wrap; }
.mem-chip {
  padding: 4px 10px; border-radius: 20px; font-size: 11.5px; font-weight: 600;
  background: var(--bg-chip); color: var(--text-2);
  border: 1px solid var(--border); cursor: pointer;
  transition: background .13s, color .13s;
  font-family: 'JetBrains Mono', monospace;
}
.mem-chip:hover { background: var(--bg-active); color: var(--text-1); }
.mem-chip.on, .mem-chip.active { background: var(--accent-dim); color: var(--accent); border-color: rgba(45,106,79,.25); }

/* ═══════════════════════════════════════════
   ANGLE TOGGLE
═══════════════════════════════════════════ */
.angle-toggle {
  display: inline-flex; border-radius: 7px; overflow: hidden;
  border: 1px solid var(--border); margin-bottom: 10px;
}
.angle-toggle button {
  padding: 5px 11px; border: none;
  background: var(--bg-chip); color: var(--text-3);
  font-size: 11.5px; font-weight: 600; cursor: pointer;
  transition: background .13s, color .13s;
  font-family: 'DM Sans', sans-serif;
}
.angle-toggle button.active { background: var(--accent); color: #fff; }
.angle-toggle button + button { border-left: 1px solid var(--border); }

/* ═══════════════════════════════════════════
   FORM INPUTS
═══════════════════════════════════════════ */
.calc-form { display: grid; gap: 12px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }

.form-field { display: flex; flex-direction: column; gap: 4px; }
.form-field label {
  font-size: 11px; font-weight: 700; color: var(--text-3);
  text-transform: uppercase; letter-spacing: .05em;
}
.form-field .field-hint { font-size: 11px; color: var(--text-3); }

.calc-input {
  height: 40px; padding: 0 12px;
  border-radius: 7px; border: 1px solid var(--border);
  background: var(--bg-bar); color: var(--text-1);
  font-size: 13.5px; font-family: 'JetBrains Mono', monospace;
  transition: border-color .13s, box-shadow .13s; width: 100%;
}
.calc-input:focus {
  outline: none; border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
}
.calc-input.result-field { background: var(--disp-bg); color: var(--accent); font-weight: 700; }

.calc-select {
  height: 40px; padding: 0 10px;
  border-radius: 7px; border: 1px solid var(--border);
  background: var(--bg-bar); color: var(--text-1);
  font-family: 'DM Sans', sans-serif; font-size: 13px; cursor: pointer; width: 100%;
  transition: border-color .13s;
}
.calc-select:focus { outline: none; border-color: var(--accent); }

/* ═══════════════════════════════════════════
   ACTION BUTTONS
═══════════════════════════════════════════ */
.action-btn {
  height: 36px; padding: 0 16px; border-radius: 7px; border: none;
  font-size: 12.5px; font-weight: 600; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center; gap: 5px;
  transition: transform .08s, background .13s;
  font-family: 'DM Sans', sans-serif; white-space: nowrap;
}
.action-btn:active { transform: scale(0.97); }
.action-btn.primary { background: var(--accent); color: #fff; }
.action-btn.primary:hover { background: var(--accent-dk); }
.action-btn.secondary {
  background: var(--bg-chip); color: var(--text-2);
  border: 1px solid var(--border);
}
.action-btn.secondary:hover { background: var(--bg-active); color: var(--text-1); }
.action-btn.danger { background: var(--danger-dim); color: var(--danger); border: 1px solid rgba(220,38,38,.25); }
.action-btn.active { background: var(--accent-dim); color: var(--accent); }

.action-row { display: flex; gap: 7px; flex-wrap: wrap; margin-top: 10px; }

/* ═══════════════════════════════════════════
   RESULT CARDS
═══════════════════════════════════════════ */
.result-card {
  background: var(--bg-bar); border-radius: 10px; padding: 14px 16px;
  border: 1px solid var(--border); margin-top: 12px;
}
.result-card h4 {
  font-size: 11px; font-weight: 700; text-transform: uppercase;
  letter-spacing: .06em; color: var(--text-3); margin-bottom: 10px;
}
.result-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(130px, 1fr)); gap: 8px;
}
.result-kv { padding: 8px 10px; background: var(--bg-chip); border-radius: 7px; }
.result-kv .rk { font-size: 11px; color: var(--text-3); }
.result-kv .rv {
  font-size: 14px; font-weight: 700; color: var(--accent);
  font-family: 'JetBrains Mono', monospace; word-break: break-all;
  margin-top: 2px;
}

/* ═══════════════════════════════════════════
   SECTION LABELS & DIVIDERS
═══════════════════════════════════════════ */
.section-title {
  font-size: 10.5px; font-weight: 700; text-transform: uppercase;
  letter-spacing: .07em; color: var(--text-3); margin-bottom: 9px; margin-top: 2px;
}
.divider { height: 1px; background: var(--border); margin: 12px 0; }

/* ═══════════════════════════════════════════
   TABLES
═══════════════════════════════════════════ */
.calc-table-wrap {
  overflow-x: auto; border-radius: 9px;
  border: 1px solid var(--border); margin-top: 10px;
}
.calc-table { width: 100%; border-collapse: collapse; font-size: 12.5px; font-family: 'JetBrains Mono', monospace; }
.calc-table th {
  background: var(--bg-chip); padding: 9px 11px;
  text-align: right; font-size: 10.5px; font-weight: 700;
  color: var(--text-3); text-transform: uppercase; letter-spacing: .05em;
  border-bottom: 1px solid var(--border); white-space: nowrap;
}
.calc-table th:first-child, .calc-table td:first-child { text-align: left; }
.calc-table td {
  padding: 8px 11px; text-align: right;
  border-bottom: 1px solid var(--border); color: var(--text-1);
}
.calc-table tr:last-child td { border-bottom: none; }
.calc-table tr:hover td { background: var(--bg-chip); }

/* ═══════════════════════════════════════════
   GRAPHING CALCULATOR
═══════════════════════════════════════════ */
.graph-container {
  background: var(--bg-bar); border-radius: 10px;
  border: 1px solid var(--border); overflow: hidden;
  position: relative; margin-bottom: 12px;
}
#graphCanvas { display: block; width: 100%; cursor: crosshair; touch-action: none; }
.graph-coords {
  position: absolute; bottom: 8px; left: 12px;
  font-size: 10.5px; font-family: 'JetBrains Mono', monospace;
  color: var(--text-3); background: var(--bg-bar);
  padding: 2px 7px; border-radius: 4px; border: 1px solid var(--border);
  pointer-events: none;
}
.trace-row {
  display: flex; align-items: center; gap: 7px;
  margin-bottom: 7px; flex-wrap: wrap;
}
.trace-color-dot {
  width: 13px; height: 13px; border-radius: 50%;
  cursor: pointer; border: 2px solid var(--border); flex-shrink: 0;
}
.trace-input { flex: 1; min-width: 120px; }

/* ═══════════════════════════════════════════
   RPN STACK
═══════════════════════════════════════════ */
.rpn-stack {
  background: var(--rpn-bg); border-radius: 10px;
  padding: 10px 14px; margin-bottom: 10px;
  font-family: 'JetBrains Mono', monospace;
  border: 1px solid var(--border);
}
.rpn-level {
  display: flex; align-items: baseline; gap: 10px;
  padding: 4px 0; border-bottom: 1px solid var(--border);
}
.rpn-level:last-child { border-bottom: none; }
.rpn-label { width: 22px; font-size: 10px; font-weight: 700; color: var(--text-3); }
.rpn-value { flex: 1; text-align: right; font-size: 17px; font-weight: 600; color: var(--rpn-text); }
.rpn-level.level-x .rpn-value { font-size: 22px; }

/* ═══════════════════════════════════════════
   STATISTICAL
═══════════════════════════════════════════ */
.stat-textarea {
  width: 100%; min-height: 90px; resize: vertical;
  background: var(--bg-bar); color: var(--text-1);
  border: 1px solid var(--border); border-radius: 7px;
  padding: 9px 11px; font-size: 13px;
  font-family: 'JetBrains Mono', monospace;
  transition: border-color .13s;
}
.stat-textarea:focus { outline: none; border-color: var(--accent); }
.stat-canvas-wrap {
  background: var(--bg-bar); border-radius: 10px;
  border: 1px solid var(--border); overflow: hidden; margin-top: 12px;
}

/* ═══════════════════════════════════════════
   PROGRAMMER CALCULATOR
═══════════════════════════════════════════ */
.base-display {
  background: var(--bg-bar); border-radius: 10px;
  padding: 12px 14px; margin-bottom: 10px; border: 1px solid var(--border);
}
.base-row {
  display: flex; align-items: baseline; gap: 9px;
  padding: 5px 0; border-bottom: 1px solid var(--border);
}
.base-row:last-child { border-bottom: none; }
.base-label { width: 34px; font-size: 10px; font-weight: 700; color: var(--text-3); text-transform: uppercase; }
.base-value { flex: 1; text-align: right; font-family: 'JetBrains Mono', monospace; font-size: 15px; font-weight: 600; color: var(--text-1); word-break: break-all; }
.base-row.active .base-label { color: var(--accent); }
.base-row.active .base-value { color: var(--accent); }

.bit-grid {
  display: flex; flex-wrap: wrap-reverse; gap: 3px;
  padding: 10px; background: var(--bg-bar);
  border-radius: 10px; border: 1px solid var(--border);
  margin-bottom: 10px; justify-content: flex-end;
}
.bit-cell {
  width: 25px; height: 28px; border-radius: 5px;
  border: 1px solid var(--border); background: var(--bg-chip);
  color: var(--text-3); font-size: 12.5px;
  font-family: 'JetBrains Mono', monospace; font-weight: 600;
  cursor: pointer; display: flex; align-items: center; justify-content: center;
  transition: background .13s, color .13s; user-select: none;
}
.bit-cell.on { background: var(--accent); color: #fff; border-color: var(--accent-dk); }
.bit-group-sep { width: 5px; }

/* ═══════════════════════════════════════════
   MATRIX GRID
═══════════════════════════════════════════ */
.matrix-grid {
  display: inline-grid; gap: 4px; padding: 8px;
  background: var(--bg-chip); border-radius: 9px; border: 1px solid var(--border);
}
.matrix-cell {
  width: 58px; height: 36px; padding: 0 7px; text-align: center;
  border-radius: 5px; border: 1px solid var(--border);
  background: var(--bg-bar); color: var(--text-1);
  font-size: 12.5px; font-family: 'JetBrains Mono', monospace;
  transition: border-color .13s;
}
.matrix-cell:focus { outline: none; border-color: var(--accent); }
.matrix-label { font-family: 'Fraunces', serif; font-size: 15px; font-weight: 600; color: var(--accent); margin-bottom: 5px; }
.matrix-section { margin-bottom: 12px; }

/* ═══════════════════════════════════════════
   PROGRAMMABLE EDITOR
═══════════════════════════════════════════ */
.prog-editor {
  width: 100%; min-height: 200px; resize: vertical;
  background: #18181a; color: #cdd6f4;
  border: 1px solid var(--border); border-radius: 7px;
  padding: 11px 13px; font-size: 13px;
  font-family: 'JetBrains Mono', monospace; line-height: 1.65;
  transition: border-color .13s;
}
[data-theme="light"] .prog-editor { background: #1e1e2e; }
.prog-editor:focus { outline: none; border-color: var(--accent); }

.prog-console {
  background: #111118; color: #a6e3a1;
  border-radius: 7px; padding: 10px 13px;
  font-size: 12.5px; font-family: 'JetBrains Mono', monospace;
  min-height: 70px; max-height: 180px; overflow-y: auto;
  border: 1px solid var(--border); line-height: 1.65;
  margin-top: 9px; white-space: pre-wrap;
}
.prog-console .err { color: #f38ba8; }
.prog-console .sys { color: #89b4fa; }

/* ═══════════════════════════════════════════
   UNIT CONVERSION
═══════════════════════════════════════════ */
.conv-pair {
  display: grid; grid-template-columns: 1fr auto 1fr;
  align-items: end; gap: 9px; margin-bottom: 10px;
}
.conv-swap-btn {
  width: 38px; height: 40px; border-radius: 7px;
  border: 1px solid var(--border); background: var(--bg-chip);
  color: var(--text-3); font-size: 16px; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: background .13s;
}
.conv-swap-btn:hover { background: var(--accent-dim); color: var(--accent); }

.fav-item {
  display: flex; align-items: center; gap: 7px;
  padding: 7px 10px; border-radius: 7px; margin-bottom: 3px;
  background: var(--bg-chip); cursor: pointer;
  transition: background .13s; font-size: 12.5px; border: 1px solid transparent;
}
.fav-item:hover { background: var(--bg-active); border-color: var(--border); }

/* ═══════════════════════════════════════════
   TOAST NOTIFICATIONS
═══════════════════════════════════════════ */
#toast-container {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  z-index: 9999; display: flex; flex-direction: column; align-items: center;
  gap: 6px; pointer-events: none;
}
.toast-pill {
  background: var(--text-1); color: var(--bg-bar);
  padding: 7px 18px; border-radius: 22px;
  font-size: 12.5px; font-weight: 500;
  box-shadow: 0 4px 16px var(--shadow-lg);
  opacity: 0; transform: translateY(10px);
  animation: toastIn .22s ease forwards;
  font-family: 'DM Sans', sans-serif;
}
@keyframes toastIn { to { opacity: 1; transform: translateY(0); } }

/* ═══════════════════════════════════════════
   CALCULATOR CONTENT — Max width (desktop)
   Prevents buttons from stretching too wide
═══════════════════════════════════════════ */
.calc-panel {
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  width: 100%;
}

/* ═══════════════════════════════════════════
   RESPONSIVE — Tablet  768 – 900 px
   Mode-tab row: icon-only (hide label text)
═══════════════════════════════════════════ */
@media (max-width: 900px) {
  /* Row 2: mode-tab labels → icon only */
  .mode-tab .mode-label { display: none; }
  .mode-tab { padding: 0 9px; min-width: 34px; justify-content: center; }
  /* Row 1: hide text labels, keep icons */
  .btn-label { display: none; }
  .mbar-btn { padding: 0 8px; }
  /* History panel becomes floating overlay */
  .history-panel { display: none; }
  .history-panel.mobile-open {
    display: flex; position: fixed; right: 0; top: 0; bottom: 0;
    z-index: 300; width: 270px;
    box-shadow: -4px 0 20px var(--shadow-lg);
  }
  .form-row { grid-template-columns: 1fr; }
  .calc-panel { padding: 13px; }
}

/* ═══════════════════════════════════════════
   RESPONSIVE — Mobile  ≤ 575 px
   Row 1: all nav actions as icons
   Row 2: all 10 mode tabs as icons (no labels)
═══════════════════════════════════════════ */
@media (max-width: 575px) {
  /* Show the mode-tab row as icon-only (same as tablet) */
  .tbar-row-2 { display: flex; }

  /* Keep hamburger hidden — row 2 replaces it */
  .ham-btn { display: none; }

  /* Row 1 tighter spacing */
  .tbar-row-1 { padding: 0 6px; gap: 0; height: 44px; }
  .mbar-icon-btn { width: 28px; }
  .mbar-btn { padding: 0 6px; }
  .mbar-sep { margin: 0 2px; }
  .app-logo em { display: none; }   /* hide "reckoner" sub-label, keep logo + "Payas" */

  /* Calculator panel */
  .calc-panel { padding: 10px; max-width: 100%; }
  .calc-display .disp-result { font-size: 26px; }
  .calc-btn { height: 50px; }
  .calc-btn.btn-sm { height: 40px; font-size: 11.5px; }
  .rpn-level.level-x .rpn-value { font-size: 18px; }
  .matrix-cell { width: 48px; }
  .result-grid { grid-template-columns: 1fr 1fr; }
  .btn-grid { gap: 5px; }
  .action-btn { padding: 0 12px; font-size: 12px; height: 34px; }
}