/* ============================================================
   Gmail Filter Builder – styles.css
   Material Design 3 inspired design system
   ============================================================ */


@font-face {
  font-family: 'Roboto';
  src: url('../fonts/Roboto-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Roboto';
  src: url('../fonts/Roboto-Medium.ttf') format('truetype');
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Roboto';
  src: url('../fonts/Roboto-Bold.ttf') format('truetype');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

/* ── CSS Custom Properties (M3 Tokens) ───────────────────── */
:root {
  /* Primary palette — Gmail Blue */
  --md-primary:          #4285F4;
  --md-primary-container:#D2E3FC;
  --md-on-primary:       #FFFFFF;
  --md-on-primary-container: #041E49;

  /* Secondary palette */
  --md-secondary:        #5f6368;
  --md-secondary-container: #E8EAED;
  --md-on-secondary:     #FFFFFF;
  --md-on-secondary-container: #1f2124;

  /* Tertiary — Gmail Green */
  --md-tertiary:         #34A853;
  --md-tertiary-container:#CEEAD6;

  /* Error — Gmail Red */
  --md-error:            #EA4335;
  --md-on-error:         #FFFFFF;
  --md-error-container:  #FCE8E6;
  --md-on-error-container: #370B01;

  /* Gmail Yellow (accent) */
  --md-gmail-yellow:     #FBBC04;
  --md-gmail-yellow-container: #FEF9C3;

  /* Surface / Background */
  --md-background:       #F8F9FA;
  --md-surface:          #FFFFFF;
  --md-surface-variant:  #F1F3F4;
  --md-surface-dim:      #E8EAED;
  --md-outline:          #DADCE0;
  --md-outline-variant:  #F1F3F4;

  /* On-Surface */
  --md-on-background:    #202124;
  --md-on-surface:       #202124;
  --md-on-surface-variant: #5f6368;

  /* Elevation shadows */
  --shadow-1: 0 1px 2px rgba(0,0,0,.08), 0 1px 3px 1px rgba(0,0,0,.06);
  --shadow-2: 0 1px 2px rgba(0,0,0,.1),  0 2px 6px 2px rgba(0,0,0,.08);
  --shadow-3: 0 4px 8px 3px rgba(0,0,0,.1), 0 1px 3px rgba(0,0,0,.12);

  /* Shape */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Typography */
  --font-base: 'Roboto', 'Segoe UI', system-ui, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  /* Spacing */
  --sp-1:  4px;
  --sp-2:  8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 20px;
  --sp-6: 24px;
  --sp-8: 32px;
  --sp-10: 40px;
  --sp-12: 48px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-std:  250ms cubic-bezier(.2,0,0,1);
}

/* ── Dark Mode Tokens ─────────────────────────────────────── */
[data-theme="dark"] {
  /* Primary */
  --md-primary:                #A8C7FA;
  --md-primary-container:      #0842A0;
  --md-on-primary:             #062E6F;
  --md-on-primary-container:   #D6E3FF;

  /* Secondary */
  --md-secondary:              #BCC7DB;
  --md-secondary-container:    #3E4759;
  --md-on-secondary:           #273141;
  --md-on-secondary-container: #D8E3F8;

  /* Tertiary */
  --md-tertiary:               #6DD58C;
  --md-tertiary-container:     #0A3818;

  /* Error */
  --md-error:                  #FFB4AB;
  --md-on-error:               #690005;
  --md-error-container:        #93000A;
  --md-on-error-container:     #FFFFFF; /* White for max contrast on dark red */

  /* Surface / Background */
  --md-background:             #1A1C1E;
  --md-surface:                #25272A;
  --md-surface-variant:        #2E3135;
  --md-surface-dim:            #3A3D41;
  --md-outline:                #44474B;
  --md-outline-variant:        #2E3135;

  /* On-Surface */
  --md-on-background:          #E2E2E7;
  --md-on-surface:             #E2E2E7;
  --md-on-surface-variant:     #C3C6CF;

  /* Elevation */
  --shadow-1: 0 1px 2px rgba(0,0,0,.35), 0 1px 3px 1px rgba(0,0,0,.25);
  --shadow-2: 0 1px 2px rgba(0,0,0,.4),  0 2px 6px 2px rgba(0,0,0,.3);
  --shadow-3: 0 4px 8px 3px rgba(0,0,0,.4), 0 1px 3px rgba(0,0,0,.4);
}

/* ── Dark Mode Specific Overrides ─────────────────────────── */
[data-theme="dark"] .query-output {
  background: #0D2A5E;
  border-color: #1558D6;
}
[data-theme="dark"] .query-text { color: #A8C7FA; }

[data-theme="dark"] .summary-box {
  background: #0A3818;
  border-left-color: var(--md-tertiary);
}
[data-theme="dark"] .summary-box p { color: #6DD58C; }
[data-theme="dark"] .summary-title  { color: #6DD58C; }

[data-theme="dark"] .example-card-query {
  background: #0842A0;
  color: #A8C7FA;
}
[data-theme="dark"] .header-donate-btn:hover { background: rgba(255,255,255,.1); }
[data-theme="dark"] .support-banner { background: linear-gradient(135deg, #3B2500 0%, #512D00 100%); }

/* ── Theme Toggle Button ──────────────────────────────────── */
.theme-toggle-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  color: var(--md-on-surface-variant);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  flex-shrink: 0;
}
.theme-toggle-btn:hover {
  background: var(--md-surface-dim);
  color: var(--md-on-surface);
}


/* ── Reset ────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-base);
  font-size: 14px;
  line-height: 1.5;
  background: var(--md-background);
  color: var(--md-on-background);
  min-height: 100dvh;
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
  word-wrap: break-word;
  overflow-wrap: break-word;
}
html { 
  width: 100%;
  max-width: 100%;
  overflow-x: hidden; 
}
img, svg { display: block; }
button, input, select, textarea { font-family: inherit; }
a { color: var(--md-primary); }

/* ── Utilities ────────────────────────────────────────────── */
.hidden { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ── App Shell ────────────────────────────────────────────── */
.app-shell {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
  box-sizing: border-box;
}
.main-content {
  flex: 1;
}

/* ── Top App Bar ──────────────────────────────────────────── */
.app-bar {
  background: var(--md-surface);
  border-bottom: 1px solid var(--md-outline);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-1);
}
.app-bar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--sp-3) var(--sp-6);
  display: flex;
  align-items: center;
  gap: var(--sp-4);
}
.app-bar-brand {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  flex: 1;
  min-width: 0;
}
.brand-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, #EA4335 0%, #FBBC04 35%, #34A853 65%, #4285F4 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.brand-icon svg { width: 20px; height: 20px; color: white; }
.brand-text { display: flex; flex-direction: column; }
.brand-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--md-on-surface);
  line-height: 1.2;
}
.brand-subtitle {
  font-size: 12px;
  color: var(--md-on-surface-variant);
  display: none;
}
@media (min-width: 600px) { .brand-subtitle { display: block; } }

.lang-select-wrapper {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}
.lang-select-wrapper svg { width: 16px; height: 16px; color: var(--md-on-surface-variant); }
#lang-select {
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-full);
  background: var(--md-surface-variant);
  color: var(--md-on-surface);
  padding: var(--sp-1) var(--sp-3);
  font-size: 13px;
  cursor: pointer;
  outline: none;
  transition: border-color var(--transition-fast);
}
#lang-select:focus { border-color: var(--md-primary); }

/* ── Navigation Bar ───────────────────────────────────────── */
.nav-bar {
  background: var(--md-surface);
  border-bottom: 1px solid var(--md-outline);
}
.nav-bar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--sp-6);
  display: flex;
  gap: 0;
  overflow-x: auto;
  scrollbar-width: none;
}
.nav-bar-inner::-webkit-scrollbar { display: none; }
.nav-link {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-4);
  font-size: 13px;
  font-weight: 500;
  color: var(--md-on-surface-variant);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  white-space: nowrap;
  flex-shrink: 0;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  cursor: pointer;
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
}
.nav-link svg { width: 18px; height: 18px; }
.nav-link:hover { color: var(--md-primary); background: var(--md-primary-container); }
.nav-link.active {
  color: var(--md-primary);
  border-bottom-color: var(--md-primary);
  font-weight: 600;
}

/* ── Main Content ─────────────────────────────────────────── */
.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--sp-6);
  width: 100%;
}

/* ── Section Layout ───────────────────────────────────────── */
.main-section { display: flex; flex-direction: column; gap: var(--sp-5); }

/* ── Cards ────────────────────────────────────────────────── */
.md-card {
  background: var(--md-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--md-outline);
  box-shadow: var(--shadow-1);
  overflow: hidden;
  transition: box-shadow var(--transition-std);
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
}
.md-card:hover { box-shadow: var(--shadow-2); }

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-4) var(--sp-6);
  border-bottom: 1px solid var(--md-outline);
  flex-wrap: wrap;
  gap: var(--sp-3);
}
.card-header-left { display: flex; align-items: center; gap: var(--sp-3); }
.card-header-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  background: var(--md-primary-container);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.card-header-icon svg { width: 18px; height: 18px; color: var(--md-primary); }
.card-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--md-on-surface);
}
.card-header-actions { display: flex; gap: var(--sp-2); }
.card-body { padding: var(--sp-5) var(--sp-6); }

/* ── Buttons ──────────────────────────────────────────────── */
.md-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: background var(--transition-fast), box-shadow var(--transition-fast), transform 80ms;
  text-decoration: none;
  white-space: nowrap;
  line-height: 1;
  height: 36px;
}
.md-btn:active { transform: scale(.97); }
.md-btn svg, .btn-icon { width: 16px; height: 16px; }

.md-btn-primary {
  background: var(--md-primary);
  color: var(--md-on-primary);
}
.md-btn-primary:hover { background: #1a6de0; box-shadow: var(--shadow-1); }

.md-btn-tonal {
  background: var(--md-primary-container);
  color: var(--md-on-primary-container);
}
.md-btn-tonal:hover { background: #bbCFF9; }

.md-btn-text {
  background: transparent;
  color: var(--md-primary);
}
.md-btn-text:hover { background: var(--md-primary-container); }

.md-btn-outline {
  background: transparent;
  color: var(--md-primary);
  border: 1px solid var(--md-outline);
}
.md-btn-outline:hover { background: var(--md-primary-container); border-color: var(--md-primary); }

.md-btn-danger {
  background: var(--md-error-container);
  color: var(--md-on-error-container);
  border: 1px solid transparent;
}
.md-btn-danger:hover { background: #F2B8B5; }
[data-theme="dark"] .md-btn-danger:hover { background: #B3261E; }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  color: var(--md-on-surface-variant);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  flex-shrink: 0;
}
.icon-btn svg { width: 18px; height: 18px; }
.icon-btn:hover { background: var(--md-surface-dim); color: var(--md-error); }

/* ── Form Inputs ──────────────────────────────────────────── */
.md-input, .md-select {
  width: 100%;
  padding: var(--sp-2) var(--sp-3);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-sm);
  background: var(--md-surface);
  color: var(--md-on-surface);
  font-size: 13px;
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  height: 40px;
}
.md-input:focus, .md-select:focus {
  border-color: var(--md-primary);
  box-shadow: 0 0 0 2px rgba(66,133,244,.2);
}
.md-input::placeholder { color: var(--md-on-surface-variant); }
.select-wrapper { position: relative; }
.select-wrapper::after {
  content: '';
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 0;
  height: 0;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid var(--md-on-surface-variant);
  pointer-events: none;
}
.md-select { appearance: none; padding-right: 28px; cursor: pointer; }

/* ── Chip ─────────────────────────────────────────────────── */
.md-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-1);
  padding: var(--sp-1) var(--sp-3);
  border-radius: var(--radius-full);
  border: 1px solid var(--md-outline);
  background: var(--md-surface-variant);
  color: var(--md-on-surface-variant);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  user-select: none;
  transition: background var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast);
  height: 32px;
}
.md-chip input[type="checkbox"] { display: none; }
.md-chip.active {
  background: var(--md-error-container);
  border-color: var(--md-error);
  color: var(--md-error);
}
.md-chip:hover { border-color: var(--md-primary); }

/* ── Condition Builder ────────────────────────────────────── */
#conditions-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}

.condition-row {
  background: var(--md-surface-variant);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  animation: slideIn 200ms var(--transition-std) both;
}
.condition-row:hover { border-color: var(--md-primary); box-shadow: var(--shadow-1); }

@keyframes slideIn {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: translateY(0); }
}

.condition-header {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: var(--sp-3);
  align-items: end;
}
@media (max-width: 640px) {
  .condition-header { grid-template-columns: 1fr; }
}

.condition-field { display: flex; flex-direction: column; gap: var(--sp-1); min-width: 0; }
.condition-value-field { flex: 1; }
.condition-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: var(--md-on-surface-variant);
}

.condition-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex-shrink: 0;
  padding-bottom: 0;
  align-self: end;
}

.condition-note {
  margin-top: var(--sp-2);
  font-size: 12px;
  color: var(--md-on-surface-variant);
  font-style: italic;
}

.condition-logic {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-top: var(--sp-3);
  padding-top: var(--sp-3);
  border-top: 1px dashed var(--md-outline);
}
.logic-label { font-size: 12px; color: var(--md-on-surface-variant); font-weight: 500; }
.logic-toggle { display: flex; border: 1px solid var(--md-outline); border-radius: var(--radius-full); overflow: hidden; }
.logic-btn {
  padding: var(--sp-1) var(--sp-3);
  font-size: 12px;
  font-weight: 600;
  border: none;
  background: transparent;
  color: var(--md-on-surface-variant);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
}
.logic-btn.active { background: var(--md-primary); color: var(--md-on-primary); }

/* ── Empty State ──────────────────────────────────────────── */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-10) var(--sp-6);
  text-align: center;
  color: var(--md-on-surface-variant);
}
.empty-state svg { width: 48px; height: 48px; opacity: .4; }
.empty-state p { font-size: 14px; max-width: 360px; }

/* ── Builder Toolbar (bottom) ─────────────────────────────── */
.builder-toolbar {
  display: flex;
  gap: var(--sp-2);
  flex-wrap: wrap;
  align-items: center;
}
.builder-toolbar-spacer { flex: 1; }

/* ── Advanced Editor ──────────────────────────────────────── */
#advanced-editor { padding: var(--sp-4); }
#advanced-query-input {
  width: 100%;
  min-height: 80px;
  font-family: var(--font-mono);
  font-size: 13px;
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-sm);
  padding: var(--sp-3);
  background: var(--md-surface-variant);
  color: var(--md-on-surface);
  resize: vertical;
  outline: none;
  transition: border-color var(--transition-fast);
}
#advanced-query-input:focus { border-color: var(--md-primary); box-shadow: 0 0 0 2px rgba(66,133,244,.2); }
.advanced-note {
  margin-top: var(--sp-2);
  font-size: 12px;
  color: var(--md-on-surface-variant);
}

/* ── Preview Card ─────────────────────────────────────────── */
.query-output {
  background: var(--md-on-primary-container);
  border-radius: var(--radius-md);
  padding: var(--sp-4) var(--sp-5);
  border: 1px solid var(--md-primary-container);
}
.query-text {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--md-primary);
  word-break: break-all;
  line-height: 1.7;
  font-weight: 500;
}
.query-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: var(--sp-3);
  flex-wrap: wrap;
  gap: var(--sp-2);
}
.char-count { font-size: 12px; color: var(--md-on-surface-variant); }
.query-actions { display: flex; gap: var(--sp-2); }

.summary-box {
  background: var(--md-tertiary-container);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
  border-left: 4px solid var(--md-tertiary);
}
.summary-box p {
  font-size: 13px;
  color: #137333;
  line-height: 1.6;
}
.summary-title {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--md-tertiary);
  margin-bottom: var(--sp-2);
}
.preview-empty {
  font-size: 14px;
  color: var(--md-on-surface-variant);
  font-style: italic;
  padding: var(--sp-4) 0;
}

/* ── Examples Section ─────────────────────────────────────── */
.section-intro { font-size: 14px; color: var(--md-on-surface-variant); margin-bottom: var(--sp-2); }
.examples-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--sp-4);
}
.example-card {
  background: var(--md-surface);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-1);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: box-shadow var(--transition-std), transform var(--transition-std);
}
.example-card:hover { box-shadow: var(--shadow-3); transform: translateY(-2px); }
.example-card-body { padding: var(--sp-4) var(--sp-4) var(--sp-3); flex: 1; min-width: 0; }
.example-card-title { font-size: 14px; font-weight: 600; color: var(--md-on-surface); margin-bottom: var(--sp-2); }
.example-card-desc  { font-size: 13px; color: var(--md-on-surface-variant); line-height: 1.5; margin-bottom: var(--sp-3); }
.example-card-query {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--md-primary);
  background: var(--md-primary-container);
  border-radius: var(--radius-xs);
  padding: var(--sp-2) var(--sp-3);
  word-break: normal;
  white-space: nowrap;
  overflow-x: auto;
  line-height: 1.6;
}
.example-card-footer {
  padding: var(--sp-3) var(--sp-4);
  border-top: 1px solid var(--md-outline);
  background: var(--md-surface-variant);
}

/* ── Help Section ─────────────────────────────────────────── */
.help-table-wrapper {
  overflow-x: auto;
  width: 100%;
}
.help-table {
  width: 100%;
  min-width: 500px;
  border-collapse: collapse;
  font-size: 13px;
}
.help-table th {
  text-align: left;
  font-weight: 600;
  color: var(--md-on-surface-variant);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .05em;
  padding: var(--sp-2) var(--sp-3);
  border-bottom: 2px solid var(--md-outline);
}
.help-table td { padding: var(--sp-2) var(--sp-3); border-bottom: 1px solid var(--md-outline-variant); vertical-align: top; }
.help-table tr:last-child td { border-bottom: none; }
.help-table tr:hover td { background: var(--md-surface-variant); }
.op-cell code {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--md-primary);
  background: var(--md-primary-container);
  padding: 1px 5px;
  border-radius: var(--radius-xs);
}
.tips-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}
.tips-list li {
  display: flex;
  gap: var(--sp-3);
  font-size: 13px;
  color: var(--md-on-surface);
  line-height: 1.5;
}
.tips-list li::before {
  content: '💡';
  flex-shrink: 0;
}
.help-tips-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--md-on-surface);
  margin-bottom: var(--sp-3);
  margin-top: var(--sp-2);
}

/* ── Support Banner ───────────────────────────────────────── */
.support-banner {
  background: linear-gradient(135deg, #FEF3C7 0%, #FDE68A 100%);
  border: 1px solid #F59E0B;
  border-radius: var(--radius-lg);
  padding: var(--sp-5) var(--sp-6);
  display: flex;
  gap: var(--sp-4);
  align-items: center;
  flex-wrap: wrap;
}
.support-icon { font-size: 32px; flex-shrink: 0; }
.support-text { flex: 1; min-width: 180px; }
.support-title { font-size: 15px; font-weight: 600; color: #92400E; margin-bottom: var(--sp-1); }
.support-desc  { font-size: 13px; color: #78350F; }
.support-links { display: flex; gap: var(--sp-2); flex-wrap: wrap; }
.support-link  {
  background: white;
  color: #92400E !important;
  border: 1px solid #F59E0B;
  text-decoration: none;
}
.support-link:hover { background: #92400E; color: white !important; }

/* ── Footer ───────────────────────────────────────────────── */
.app-footer {
  border-top: 1px solid var(--md-outline);
  background: var(--md-surface);
  padding: var(--sp-4) var(--sp-6);
  margin-top: var(--sp-8);
}
.app-footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--sp-2);
  font-size: 12px;
  color: var(--md-on-surface-variant);
}
.footer-disclaimer { font-style: italic; }

/* ── Save Filter Modal ────────────────────────────────────── */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: var(--sp-4);
  animation: modal-fade-in 0.18s ease;
}
.modal-overlay.hidden { display: none; }

@keyframes modal-fade-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

.modal-card {
  background: var(--md-surface);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-5);
  width: 100%;
  max-width: 420px;
  overflow: hidden;
  animation: modal-slide-in 0.22s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes modal-slide-in {
  from { transform: translateY(24px) scale(0.97); opacity: 0; }
  to   { transform: translateY(0)    scale(1);    opacity: 1; }
}
.modal-header {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-5) var(--sp-5) var(--sp-3);
  border-bottom: 1px solid var(--md-outline-variant);
}
.modal-header-icon {
  width: 36px; height: 36px;
  border-radius: var(--radius-md);
  background: var(--md-primary-container);
  color: var(--md-primary);
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.modal-header-icon svg { width: 18px; height: 18px; }
.modal-title { font-size: 16px; font-weight: 600; color: var(--md-on-surface); }
.modal-body  { padding: var(--sp-4) var(--sp-5); display: flex; flex-direction: column; gap: var(--sp-3); }
.modal-label { font-size: 13px; color: var(--md-on-surface-variant); font-weight: 500; }
.modal-input {
  width: 100%;
  padding: var(--sp-3) var(--sp-4);
  border: 1.5px solid var(--md-outline);
  border-radius: var(--radius-md);
  background: var(--md-surface);
  color: var(--md-on-surface);
  font-family: var(--font-base);
  font-size: 14px;
  outline: none;
  transition: border-color var(--transition-std), box-shadow var(--transition-std);
  box-sizing: border-box;
}
.modal-input:focus {
  border-color: var(--md-primary);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--md-primary) 18%, transparent);
}
.modal-hint {
  font-size: 12px;
  color: var(--md-on-surface-variant);
  background: var(--md-surface-variant);
  border-radius: var(--radius-sm);
  padding: var(--sp-2) var(--sp-3);
  border-left: 3px solid var(--md-primary);
}
.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-5) var(--sp-5);
}

/* ── Save Snackbar ────────────────────────────────────────── */
.snackbar {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(0);
  background: var(--md-on-surface);
  color: var(--md-surface);
  border-radius: var(--radius-full);
  padding: var(--sp-3) var(--sp-4) var(--sp-3) var(--sp-5);
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  font-size: 14px;
  box-shadow: var(--shadow-3);
  z-index: 999;
  min-width: 240px;
  max-width: 90vw;
  animation: snackbar-in 0.28s cubic-bezier(0.34,1.56,0.64,1);
  white-space: nowrap;
}
.snackbar.hidden {
  display: none;
}
@keyframes snackbar-in {
  from { transform: translateX(-50%) translateY(40px); opacity: 0; }
  to   { transform: translateX(-50%) translateY(0);    opacity: 1; }
}
.snackbar-action {
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-base);
  font-size: 13px;
  font-weight: 700;
  color: var(--md-primary-container);
  padding: var(--sp-1) var(--sp-2);
  border-radius: var(--radius-sm);
  transition: background var(--transition-std);
  letter-spacing: .04em;
  text-transform: uppercase;
}
.snackbar-action:hover { background: rgba(255,255,255,0.12); }

/* ── Scrollbar ────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--md-outline); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background: var(--md-secondary); }

/* ── Focus-visible polish ─────────────────────────────────── */
:focus-visible {
  outline: 2px solid var(--md-primary);
  outline-offset: 2px;
  border-radius: var(--radius-xs);
}
button:focus:not(:focus-visible) { outline: none; }

/* ── Responsive tweaks ────────────────────────────────────── */
@media (max-width: 600px) {
  .brand-title { display: none; }
}

@media (max-width: 480px) {
  .app-bar-inner { padding: var(--sp-2) var(--sp-4); gap: var(--sp-3); }
  .nav-bar-inner { padding: 0 var(--sp-4); }
  .main-content  { padding: var(--sp-4); }
  .card-header   { padding: var(--sp-3) var(--sp-4); }
  .card-body     { padding: var(--sp-4); }
  
  /* Stack buttons internally */
  .builder-toolbar { flex-direction: column; gap: var(--sp-2); }
  .builder-toolbar .md-btn { width: 100%; flex: none; justify-content: center; height: auto; padding: 10px; white-space: normal; line-height: 1.4; }
  
  .card-header-actions { flex-direction: column; width: 100%; margin-top: var(--sp-2); }
  .card-header-actions .md-btn { width: 100%; flex: none; justify-content: center; height: auto; padding: 10px; white-space: normal; line-height: 1.4; }
  
  .query-meta { flex-direction: column; align-items: stretch; gap: var(--sp-3); }
  .query-actions { flex-direction: column; width: 100%; justify-content: stretch; }
  .query-actions .md-btn, .query-actions #btn-open-gmail { width: 100%; flex: none; justify-content: center; height: auto; padding: 10px; white-space: normal; line-height: 1.4; }

  .condition-actions { margin-top: var(--sp-2); }
  #lang-select { max-width: 100px; text-overflow: ellipsis; overflow: hidden; }
  
  /* Guide adjustments for small screens */
  .guide-step { flex-direction: column; gap: var(--sp-3); padding: var(--sp-3); }
  .guide-step-number { width: 32px; height: 32px; font-size: 14px; }
}

/* ── Header Donate Button ─────────────────────────────────── */
.header-donate-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--md-on-surface-variant);
  text-decoration: none;
  transition: background var(--transition-fast), color var(--transition-fast);
  flex-shrink: 0;
}
.header-donate-btn:hover {
  background: #FCE8E6;
  color: #D93025;
}

/* ── Footer Donate Link ───────────────────────────────────── */
.footer-donate-link {
  color: var(--md-primary);
  text-decoration: none;
  font-size: 12px;
  transition: opacity var(--transition-fast);
}
.footer-donate-link:hover { opacity: .75; }

/* ── Support Toast ────────────────────────────────────────── */
#support-toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 300;
  width: 320px;
  background: linear-gradient(135deg, #1558D6 0%, #0B3D9E 100%);
  border-radius: var(--radius-xl);
  box-shadow: 0 8px 32px rgba(21,88,214,.35), 0 2px 8px rgba(0,0,0,.15);
  color: #fff;
  padding: var(--sp-5);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  /* Hidden state */
  transform: translateY(calc(100% + 32px));
  opacity: 0;
  pointer-events: none;
  transition: transform 420ms cubic-bezier(.2,0,0,1), opacity 420ms;
}
#support-toast.toast-visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.toast-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--sp-2);
}
.toast-title {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.3;
  flex: 1;
}
.toast-close-btn {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  border: none;
  background: rgba(255,255,255,.15);
  color: #fff;
  cursor: pointer;
  font-size: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background var(--transition-fast);
  line-height: 1;
}
.toast-close-btn:hover { background: rgba(255,255,255,.3); }

.toast-desc {
  font-size: 13px;
  line-height: 1.5;
  color: rgba(255,255,255,.88);
}
.toast-links {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}
.toast-cta-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-2) var(--sp-4);
  border-radius: var(--radius-full);
  background: rgba(255,255,255,.2);
  border: 1px solid rgba(255,255,255,.35);
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  transition: background var(--transition-fast);
}
.toast-cta-link:hover { background: rgba(255,255,255,.32); }

.toast-dismiss {
  display: block;
  text-align: center;
  font-size: 11px;
  color: rgba(255,255,255,.6);
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  transition: color var(--transition-fast);
}
.toast-dismiss:hover { color: rgba(255,255,255,.9); }

@media (max-width: 480px) {
  #support-toast {
    left: 12px;
    right: 12px;
    width: auto;
    bottom: 16px;
  }
}

/* ── Google Color Accents ─────────────────────────────────── */

/* 1) Builder: AND = Gmail Yellow, OR = Gmail Blue */
.logic-btn:first-child.active {
  background: var(--md-gmail-yellow);
  color: #3E2000;
}
.logic-btn:last-child.active {
  background: #4285F4;
  color: #FFFFFF;
}

/* 2) Example cards: 4-color top border + matching code snippets */
.example-card:nth-child(4n+1) { border-top: 3px solid #EA4335; }
.example-card:nth-child(4n+2) { border-top: 3px solid #4285F4; }
.example-card:nth-child(4n+3) { border-top: 3px solid #34A853; }
.example-card:nth-child(4n+4) { border-top: 3px solid #FBBC04; }

.example-card:nth-child(4n+1) .example-card-query { background: #FCE8E6; color: #C5221F; }
.example-card:nth-child(4n+2) .example-card-query { background: #D2E3FC; color: #1967D2; }
.example-card:nth-child(4n+3) .example-card-query { background: #CEEAD6; color: #137333; }
.example-card:nth-child(4n+4) .example-card-query { background: #FEF9C3; color: #856000; }

/* 3) Help table: operator badge 4-color cycle */
.help-table tbody tr:nth-child(4n+1) .op-cell code { background: #FCE8E6; color: #C5221F; }
.help-table tbody tr:nth-child(4n+2) .op-cell code { background: #D2E3FC; color: #1967D2; }
.help-table tbody tr:nth-child(4n+3) .op-cell code { background: #CEEAD6; color: #137333; }
.help-table tbody tr:nth-child(4n+4) .op-cell code { background: #FEF9C3; color: #856000; }

/* Dark mode variants */
[data-theme="dark"] .logic-btn:last-child.active {
  background: #856000;
  color: #FDD663;
}
[data-theme="dark"] .example-card:nth-child(4n+1) .example-card-query { background: #4E1F1C; color: #F28B82; }
[data-theme="dark"] .example-card:nth-child(4n+2) .example-card-query { background: #1A3A6E; color: #8AB4F8; }
[data-theme="dark"] .example-card:nth-child(4n+3) .example-card-query { background: #1B3D2B; color: #81C995; }
[data-theme="dark"] .example-card:nth-child(4n+4) .example-card-query { background: #3D3400; color: #FDD663; }

[data-theme="dark"] .help-table tbody tr:nth-child(4n+1) .op-cell code { background: #4E1F1C; color: #F28B82; }
[data-theme="dark"] .help-table tbody tr:nth-child(4n+2) .op-cell code { background: #1A3A6E; color: #8AB4F8; }
[data-theme="dark"] .help-table tbody tr:nth-child(4n+3) .op-cell code { background: #1B3D2B; color: #81C995; }
[data-theme="dark"] .help-table tbody tr:nth-child(4n+4) .op-cell code { background: #3D3400; color: #FDD663; }

/* ── Guide Section ────────────────────────────────────────── */

.guide-steps {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-top: 24px;
}

.guide-step {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 18px 20px;
  border-radius: var(--radius-md);
  transition: background 0.15s;
}
.guide-step:hover { background: var(--md-surface-variant); }

/* Gmail 4-color numbered badges */
.guide-step:nth-child(4n+1) .guide-step-number { background: #EA4335; }
.guide-step:nth-child(4n+2) .guide-step-number { background: #4285F4; }
.guide-step:nth-child(4n+3) .guide-step-number { background: #34A853; }
.guide-step:nth-child(4n+4) .guide-step-number { background: #FBBC04; color: #3E2000; }

.guide-step-number {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--md-primary);
  color: #FFF;
  font-family: 'Google Sans', sans-serif;
  font-size: 15px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 2px;
}

.guide-step-content { flex: 1; }

.guide-step-title {
  font-family: 'Google Sans', sans-serif;
  font-size: 15px;
  font-weight: 600;
  color: var(--md-on-surface);
  margin: 0 0 6px;
  line-height: 1.35;
}

.guide-step-desc {
  font-size: 14px;
  color: var(--md-on-surface-variant);
  line-height: 1.65;
  margin: 0;
}

/* Step 5 callout — the critical hidden-arrow tip */
.guide-tip-callout {
  margin-top: 12px;
  padding: 12px 16px;
  background: #FEF9C3;
  border-left: 4px solid #FBBC04;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.guide-tip-label {
  display: block;
  font-family: 'Google Sans', sans-serif;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #856000;
  margin-bottom: 6px;
}

.guide-tip-callout p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: #5C4200;
}

/* Done card */
.guide-done-card {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 24px;
  padding: 18px 20px;
  background: #CEEAD6;
  border-radius: var(--radius-md);
  color: #137333;
}

.guide-done-icon { font-size: 24px; flex-shrink: 0; }

.guide-done-card p {
  margin: 0;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.5;
  color: #137333;
}

/* Dark mode overrides */
[data-theme="dark"] .guide-step:hover { background: rgba(255,255,255,0.06); }

[data-theme="dark"] .guide-tip-callout {
  background: #3D3400;
  border-left-color: #FBBC04;
}
[data-theme="dark"] .guide-tip-label { color: #FDD663; }
[data-theme="dark"] .guide-tip-callout p { color: #FEF9C3; }

[data-theme="dark"] .guide-done-card { background: #1B3D2B; }
[data-theme="dark"] .guide-done-card p { color: #81C995; }

/* Inline icon for guide steps (Gmail search options sliders) */
.inline-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  margin: 0 2px;
  padding: 3px;
  border-radius: 4px;
  background: rgba(0,0,0,0.05);
  border: 1px solid rgba(0,0,0,0.1);
  vertical-align: middle;
  position: relative;
  top: -1px;
}
[data-theme="dark"] .inline-icon {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.2);
}
.inline-icon svg {
  width: 100%;
  height: 100%;
  color: inherit;
} 

/* ── Phase 5 Animations & Refinements ─────────────────────── */

/* 1) Modal & Overlay Animations */
.modal-overlay {
  transition: opacity 300ms ease, backdrop-filter 300ms ease;
  backdrop-filter: blur(0px);
}
.modal-overlay:not(.hidden) {
  backdrop-filter: blur(4px);
  display: flex;
}

.modal-card {
  transform: scale(0.9) translateY(20px);
  opacity: 0;
  transition: transform 400ms cubic-bezier(0.34, 1.56, 0.64, 1), opacity 300ms ease;
}
.modal-overlay:not(.hidden) .modal-card {
  transform: scale(1) translateY(0);
  opacity: 1;
}

/* 2) Delete Modal (Danger Theme) */
.modal-card-danger {
  border-top: 4px solid var(--md-error) !important;
}
.modal-card-danger .modal-header-icon {
  background: #F9DEDC; /* M3 Error container */
  color: var(--md-error);
}
.md-card-danger .modal-header-icon {
  background: var(--md-error-container);
  color: var(--md-on-error-container);
}

/* 3) Snackbar Animation */
.snackbar {
  transform: translateX(-50%) translateY(100px);
  opacity: 0;
  transition: transform 400ms cubic-bezier(0.2, 0, 0, 1), opacity 300ms;
}
.snackbar:not(.hidden) {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* 4) Condition Row Animation */
@keyframes rowFadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.condition-row {
  animation: rowFadeIn 300ms ease-out both;
}

/* 5) PWA & iOS Hints */
.help-card {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  margin-top: var(--sp-4);
}
.ios-hint {
  margin-top: var(--sp-3);
  padding: var(--sp-4);
  background: #E8F0FE;
  border-left: 4px solid var(--md-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--md-primary);
}
[data-theme="dark"] .ios-hint {
  background: #1A3A6E;
  color: #D2E3FC;
}

/* 6) Empty Library Placeholder */
.library-empty-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--sp-10) var(--sp-6);
  text-align: center;
  background: var(--md-surface-variant);
  border: 2px dashed var(--md-outline-variant);
  border-radius: var(--radius-xl);
  opacity: 0.8;
  margin: var(--sp-4) 0;
}
.library-empty-icon {
  font-size: 48px;
  margin-bottom: var(--sp-3);
  opacity: 0.5;
}
.library-empty-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: var(--sp-1);
  color: var(--md-on-surface);
}
.library-empty-card p {
  font-size: 14px;
  color: var(--md-on-surface-variant);
}