/* Stu-Decks — white/grey with maroon accents, with a dark version that
   follows the system setting. All colours are tokens here, so the theme can be
   changed in one place.

   The only maroon is #510400 — never a lighter tint — in both modes:
     --accent      maroon fills (buttons, icon badges, decorative stripes)
     --accent-ink  text, icons and outlines: #510400 in light mode; in dark
                   mode it is neutral light grey, because #510400 text on
                   charcoal is unreadable (contrast 1.03:1). In dark mode
                   maroon therefore only appears as fills behind white.
     --accent-soft neutral grey for hover/selected backgrounds (no pink tints) */

:root {
  --accent: #510400;          /* maroon */
  --accent-ink: #510400;
  --accent-soft: #ececf0;     /* hover/selected backgrounds */
  --on-accent: #ffffff;
  --bg: #f3f3f5;
  --surface: #ffffff;
  --surface-2: #f8f8fa;
  --border: #e1e1e6;
  --border-strong: #c9c9d1;
  --text: #1d1d22;
  --muted: #676773;
  --right: #15803d;
  --right-bg: #e8f6ed;
  --wrong: #b91c1c;
  --wrong-bg: #fdeded;
  --learning: #d97706;
  --not-studied: #d9d9df;
  --shadow: 0 1px 2px rgb(20 20 30 / 6%), 0 6px 16px rgb(20 20 30 / 6%);
  --shadow-lift: 0 2px 4px rgb(20 20 30 / 8%), 0 12px 28px rgb(20 20 30 / 10%);
  --radius: 12px;
  --radius-sm: 8px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --accent: #510400;        /* same maroon as light mode */
    --accent-ink: #ececf0;    /* neutral: maroon text would be unreadable here */
    --accent-soft: #34343b;
    --on-accent: #ffffff;
    --bg: #161618;
    --surface: #222226;
    --surface-2: #2a2a2f;
    --border: #36363d;
    --border-strong: #4a4a52;
    --text: #ececf0;
    --muted: #a3a3ad;
    --right: #4ade80;
    --right-bg: #173222;
    --wrong: #f87171;
    --wrong-bg: #3b1c1c;
    --learning: #f59e0b;
    --not-studied: #3d3d45;
    --shadow: 0 1px 2px rgb(0 0 0 / 30%), 0 6px 16px rgb(0 0 0 / 25%);
    --shadow-lift: 0 2px 4px rgb(0 0 0 / 35%), 0 12px 28px rgb(0 0 0 / 35%);
    color-scheme: dark;
  }
}

/* ---------- base ---------- */

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, sans-serif;
}

h1, h2, h3 { line-height: 1.25; margin: 0; }
h1 { font-size: 1.75rem; }
h2 { font-size: 1.15rem; }

a { color: var(--accent-ink); }
[hidden] { display: none !important; }

.muted { color: var(--muted); }

main {
  max-width: 1040px;
  margin: 0 auto;
  padding: 28px 16px 64px;
}

kbd {
  font: 600 0.72em/1 ui-monospace, monospace;
  padding: 3px 5px;
  margin-left: 6px;
  border-radius: 4px;
  border: 1px solid currentColor;
  opacity: 0.6;
}

/* ---------- top bar ---------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 24px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.2rem;
  color: var(--accent-ink);
  text-decoration: none;
}

.topbar-user { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; justify-content: flex-end; }

.brand-mark { width: 28px; height: 28px; fill: none; stroke: var(--accent-ink); stroke-width: 2; }
.brand-mark rect:last-child { fill: var(--accent); }

/* ---------- buttons & forms ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 9px 16px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--text);
  font: inherit;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.05s;
}
.btn:hover { background: var(--surface-2); border-color: var(--accent-ink); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.55; cursor: default; }

.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent); border-color: var(--accent); box-shadow: inset 0 0 0 2px rgb(255 255 255 / 35%); }
.btn-danger { background: var(--wrong); border-color: var(--wrong); color: #fff; }
.btn-danger:hover { background: var(--wrong); filter: brightness(1.1); }
.btn-right { border-color: var(--right); color: var(--right); }
.btn-wrong { border-color: var(--wrong); color: var(--wrong); }
.btn-round { width: 48px; height: 48px; padding: 0; border-radius: 50%; font-size: 1.2rem; }

.button-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.button-row.end { justify-content: flex-end; }

input[type="text"], input[type="email"], input[type="password"], input[type="number"],
input[type="search"], select {
  font: inherit;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 9px 12px;
}
input:focus-visible, select:focus-visible, .btn:focus-visible, .flashcard:focus-visible,
.choice:focus-visible, .mode-card:focus-visible, .deck-tile:focus-visible, .tile:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent-ink) 45%, transparent);
  outline-offset: 2px;
}
input[type="number"] { width: 110px; }
input:disabled, select:disabled { opacity: 0.55; cursor: not-allowed; }

label { font-weight: 600; }
label.inline { display: inline-flex; align-items: center; gap: 8px; font-weight: 500; }
.check { display: flex; align-items: center; gap: 8px; font-weight: 500; margin: 14px 0; }
.check input { width: 18px; height: 18px; accent-color: var(--accent); }

.form-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin: 14px 0; }
.form-error { color: var(--wrong); font-weight: 600; margin: 10px 0 0; }
.optional { font-weight: 400; font-size: 0.85rem; color: var(--muted); margin-left: 4px; }
.field-hint { font-size: 0.88rem; color: var(--muted); margin: 6px 0 0; }

/* ---------- finding shared decks ---------- */

.search-panel { margin-top: 0; }
.search-fields {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}
.field { min-width: 0; }
.field label { display: block; margin-bottom: 6px; }
.field input, .field select { width: 100%; }
.results-title { font-size: 1rem; margin: 24px 0 12px; }
.results-title:empty { display: none; }

.group-title { font-size: 1rem; margin: 26px 0 12px; overflow-wrap: anywhere; }
.group-title:first-child { margin-top: 0; }
.group-title .course { color: var(--accent-ink); }
.group-title .muted { font-weight: 500; }

.tile-tags { font-size: 0.88rem; color: var(--muted); overflow-wrap: anywhere; }
.tile-tags b { color: var(--accent-ink); }
.deck-tags { margin: 6px 0 0; font-weight: 600; overflow-wrap: anywhere; }
.deck-tags:empty { display: none; }
.deck-tags .course { color: var(--accent-ink); }

/* ---------- shared blocks ---------- */

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-top: 20px;
}

.back {
  display: inline-block;
  margin-bottom: 14px;
  font-weight: 600;
  text-decoration: none;
}
.back:hover { text-decoration: underline; }

.page-head { margin-bottom: 22px; }
.page-head p { margin: 6px 0 0; }

.section-title { margin: 36px 0 12px; }

.empty {
  text-align: center;
  padding: 48px 16px;
  border: 2px dashed var(--border-strong);
  border-radius: var(--radius);
  color: var(--muted);
}

.notice { padding: 12px 16px; border-radius: var(--radius-sm); margin-top: 20px; }
.notice-warn { background: var(--wrong-bg); color: var(--wrong); }

.loading { text-align: center; color: var(--muted); padding: 40px; }

/* progress bar: mastered / still learning / not studied */
.progress {
  display: flex;
  height: 10px;
  border-radius: 999px;
  overflow: hidden;
  background: var(--not-studied);
}
.progress-lg { height: 12px; margin-top: 14px; }
.progress span { display: block; height: 100%; transition: width 0.3s; }
.progress .p-mastered { background: var(--right); }
.progress .p-learning { background: var(--learning); }

.legend { display: flex; flex-wrap: wrap; gap: 14px; margin: 8px 0 0; font-size: 0.9rem; color: var(--muted); }
.legend i { display: inline-block; width: 10px; height: 10px; border-radius: 3px; margin-right: 5px; }

/* ---------- home: deck tiles ---------- */

.deck-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 18px;
}

.deck-tile {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 4px solid var(--accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: inherit;
  text-decoration: none;
  transition: box-shadow 0.15s, transform 0.15s;
}
.deck-tile:hover { box-shadow: var(--shadow-lift); transform: translateY(-2px); }
.deck-tile h2 { font-size: 1.2rem; overflow-wrap: anywhere; }
.deck-tile p { margin: 0; }
.tile-stats { font-size: 0.9rem; color: var(--muted); }

/* ---------- deck page ---------- */

.deck-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  flex-wrap: wrap;
}
.deck-head h1 { overflow-wrap: anywhere; }
.deck-head p { margin: 6px 0 0; }

.menu { position: relative; }
.menu-list {
  position: absolute;
  right: 0;
  top: calc(100% + 6px);
  z-index: 5;
  min-width: 220px;
  padding: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lift);
}
.menu-list button {
  display: block;
  width: 100%;
  padding: 9px 12px;
  border: 0;
  border-radius: 6px;
  background: none;
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
}
.menu-list button:hover { background: var(--accent-soft); }
.menu-list button.danger { color: var(--wrong); }
.menu-list hr { border: 0; border-top: 1px solid var(--border); margin: 6px 0; }

.mode-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 14px;
  margin-top: 24px;
}
.mode-card {
  display: grid;
  grid-template-columns: 40px 1fr;
  grid-template-rows: auto auto;
  column-gap: 12px;
  align-items: center;
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: inherit;
  text-decoration: none;
  cursor: pointer;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.mode-card:hover { border-color: var(--accent-ink); box-shadow: var(--shadow-lift); }
.mode-card svg {
  grid-row: span 2;
  width: 40px;
  height: 40px;
  padding: 7px;
  border-radius: 10px;
  background: var(--accent);
  fill: none;
  stroke: var(--on-accent);
  stroke-width: 2;
  stroke-linecap: round;
}
.mode-name { font-weight: 700; }
.mode-desc { font-size: 0.88rem; color: var(--muted); }
.mode-card.disabled { opacity: 0.45; pointer-events: none; }

.stats-row {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 14px;
  margin-top: 18px;
}
.stat-card {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.stat-card h2 { font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); margin-bottom: 10px; }
.stat-card p { margin: 6px 0 0; }
.stat-big { font-size: 1.8rem; font-weight: 800; color: var(--accent-ink); }

.table-wrap { overflow-x: auto; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); }
.history-table { width: 100%; border-collapse: collapse; font-size: 0.95rem; }
.history-table th, .history-table td { padding: 10px 14px; text-align: left; white-space: nowrap; }
.history-table th { background: var(--surface-2); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); }
.history-table tr + tr td { border-top: 1px solid var(--border); }
.history-table .pct { font-weight: 700; }

.card-list { display: grid; gap: 10px; }
.card-row {
  display: grid;
  grid-template-columns: minmax(140px, 1fr) 2fr;
  gap: 20px;
  padding: 16px 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.card-row .term { font-weight: 700; border-right: 2px solid var(--border); padding-right: 20px; }
.card-row.mc { grid-template-columns: 1fr; gap: 8px; }
.card-row ol { margin: 4px 0 0; padding-left: 0; list-style: none; color: var(--muted); }
.card-row .card-answer { color: var(--right); font-weight: 600; }

/* ---------- study pages ---------- */

.study-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px 18px;
}
.study-head .back { width: 100%; margin-bottom: 4px; }
.study-head p { margin: 0; }
.study-controls { margin-left: auto; display: flex; gap: 10px; align-items: center; }

/* flashcards */
.flashcard {
  margin: 24px auto 0;
  max-width: 760px;
  height: 380px;
  perspective: 1400px;
  cursor: pointer;
  outline: none;
  border-radius: var(--radius);
}
.flashcard-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.45s ease;
  transform-style: preserve-3d;
}
.flashcard.flipped .flashcard-inner { transform: rotateX(180deg); }
.flashcard.instant .flashcard-inner { transition: none; }
.face {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lift);
  backface-visibility: hidden;
  overflow-y: auto;
}
.face-back { transform: rotateX(180deg); border-bottom: 4px solid var(--accent); }
.face-text { font-size: 1.45rem; text-align: center; overflow-wrap: anywhere; }
.face-text.long { font-size: 1.1rem; }
.face-text ol { text-align: left; font-size: 1rem; margin: 16px 0 0; padding-left: 0; list-style: none; }
.face-text ol li { margin: 4px 0; }
.fc-nav { display: flex; align-items: center; justify-content: center; gap: 24px; margin-top: 20px; font-weight: 600; }
.hint { text-align: center; color: var(--muted); font-size: 0.9rem; }

/* learn */
.q-meta {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
}
.q-text { font-size: 1.35rem; font-weight: 600; margin: 14px 0 22px; overflow-wrap: anywhere; }

.choices { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 12px; }
.choice {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  width: 100%;
  padding: 14px 16px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: border-color 0.12s, background 0.12s;
}
.choice:hover:not(:disabled) { border-color: var(--accent-ink); background: var(--accent-soft); }
.choice:disabled { cursor: default; }
.choice .letter {
  flex: none;
  display: inline-grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--surface-2);
  border: 1px solid var(--border-strong);
  font-size: 0.8rem;
  font-weight: 700;
}
.choice.right { border-color: var(--right); background: var(--right-bg); }
.choice.wrong { border-color: var(--wrong); background: var(--wrong-bg); }

.written { display: flex; gap: 10px; flex-wrap: wrap; }
.written input { flex: 1 1 260px; font-size: 1.1rem; }

.answer-box {
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  background: var(--right-bg);
  color: var(--right);
  font-weight: 600;
  font-size: 1.1rem;
}

.feedback { margin-top: 18px; padding: 12px 16px; border-radius: var(--radius-sm); font-weight: 600; }
.feedback.right { background: var(--right-bg); color: var(--right); }
.feedback.wrong { background: var(--wrong-bg); color: var(--wrong); }

#ls-lists h3 { font-size: 1rem; margin-top: 18px; }
.summary-list { display: grid; gap: 10px; margin: 10px 0 22px; }
.summary-item { padding: 12px 16px; border: 1px solid var(--border); border-radius: var(--radius-sm); background: var(--surface-2); }
.summary-item p { margin: 2px 0; }
.summary-item .answer { color: var(--right); }
.summary-item .missed { color: var(--wrong); font-size: 0.9rem; }

/* test */
.test-bar {
  position: sticky;
  top: 57px;
  z-index: 4;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 20px;
  padding: 12px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  font-weight: 600;
}
.timer { font-variant-numeric: tabular-nums; font-weight: 800; font-size: 1.1rem; }
.timer.low { color: var(--wrong); }

.test-questions { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 16px; }
.test-q {
  padding: 22px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.test-q .q-meta { margin-bottom: 8px; }
.test-q .q-text { font-size: 1.15rem; margin: 0 0 16px; }
.test-q .choices { grid-template-columns: 1fr; gap: 8px; }
.test-q.is-answered { border-left: 4px solid var(--accent-ink); }
.choice.selected { border-color: var(--accent-ink); background: var(--accent-soft); }
.choice.selected .letter { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.review .test-q.is-right { border-left: 4px solid var(--right); }
.review .test-q.is-wrong { border-left: 4px solid var(--wrong); }
.tag { font-size: 0.8rem; font-weight: 700; padding: 2px 8px; border-radius: 999px; }
.tag.right { background: var(--right-bg); color: var(--right); }
.tag.wrong { background: var(--wrong-bg); color: var(--wrong); }

.results-head { text-align: center; }
.results-head .button-row { justify-content: center; }
.score { font-size: 3rem; font-weight: 800; margin: 0; color: var(--accent-ink); }

/* match */
.match-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-top: 20px;
}
.tile {
  min-height: 130px;
  padding: 12px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--text);
  font: inherit;
  font-size: 0.95rem;
  overflow-wrap: anywhere;
  cursor: pointer;
  transition: border-color 0.12s, background 0.12s, opacity 0.25s, transform 0.25s;
}
.tile.small-text { font-size: 0.8rem; }
.tile:hover { border-color: var(--accent-ink); }
.tile.selected { border-color: var(--accent-ink); background: var(--accent-soft); }
.tile.wrong { border-color: var(--wrong); background: var(--wrong-bg); animation: shake 0.3s; }
.tile.matched { opacity: 0; transform: scale(0.9); pointer-events: none; }

@keyframes shake {
  25% { transform: translateX(-5px); }
  75% { transform: translateX(5px); }
}

/* ---------- dialogs & toast ---------- */

dialog {
  width: min(480px, calc(100vw - 32px));
  padding: 26px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow-lift);
}
dialog::backdrop { background: rgb(15 10 12 / 45%); }
dialog h2 { margin-bottom: 8px; }
.login-panel { max-width: 420px; margin: 40px auto 0; }
.login-panel label { display: block; margin: 16px 0 6px; }
.login-panel input { width: 100%; }
.login-switch { margin: 18px 0 0; }

.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 600;
}

dialog label { display: block; margin: 16px 0 6px; }
dialog input[type="text"], dialog input[type="file"] { width: 100%; }
dialog input[type="file"] { font: inherit; }

.toast {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translateX(-50%);
  z-index: 20;
  max-width: calc(100vw - 32px);
  padding: 12px 18px;
  border-radius: var(--radius-sm);
  background: var(--text);
  color: var(--surface);
  font-weight: 600;
  box-shadow: var(--shadow-lift);
}
.toast.error { background: var(--wrong); color: #fff; }

/* ---------- small screens ---------- */

@media (max-width: 720px) {
  main { padding: 20px 16px 48px; }
  .topbar { padding: 10px 16px; }
  .stats-row { grid-template-columns: 1fr; }
  .card-row { grid-template-columns: 1fr; gap: 8px; }
  .card-row .term { border-right: 0; padding-right: 0; }
  .match-grid { grid-template-columns: repeat(2, 1fr); }
  .flashcard { height: 320px; }
  .face-text { font-size: 1.2rem; }
  .study-controls { margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

/* ---------- footer, privacy policy & cookie consent ---------- */

.site-footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px 24px;
  padding: 20px 16px 28px;
  border-top: 1px solid var(--border);
  font-size: 0.9rem;
}
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--accent-ink); }

.policy { max-width: 760px; }
.policy h2 { margin: 32px 0 10px; }
.policy p, .policy li { overflow-wrap: anywhere; }
.policy li + li { margin-top: 6px; }

.consent {
  position: fixed;
  z-index: 50;
  left: 16px;
  right: 16px;
  bottom: 16px;
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 24px;
  padding: 18px 22px;
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-top: 4px solid var(--accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lift);
}
.consent-body { flex: 1 1 380px; }
.consent h2 { font-size: 1.05rem; margin-bottom: 6px; }
.consent p { margin: 0; font-size: 0.92rem; }
.consent-buttons { display: flex; flex-wrap: wrap; gap: 10px; }
.consent-buttons .btn { flex: 1 1 auto; }