:root {
  --bg: #f5f6fb;
  --bg-elevated: #ffffff;
  --text: #1c1e2b;
  --text-muted: #5b5f77;
  --border: #e3e5f0;
  --accent: #6366f1;
  --accent-soft: #eef0fe;
  --accent-contrast: #ffffff;
  --success: #16a34a;
  --success-soft: #e8f7ee;
  --warn: #d97706;
  --warn-soft: #fef3e2;
  --danger: #dc2626;
  --danger-soft: #fde8e8;
  --shadow: 0 1px 2px rgba(20, 20, 43, 0.04), 0 8px 24px rgba(20, 20, 43, 0.06);
  --radius: 14px;
  --radius-sm: 9px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14151f;
    --bg-elevated: #1c1e2b;
    --text: #eceef7;
    --text-muted: #9a9db3;
    --border: #2b2d3d;
    --accent: #8385f5;
    --accent-soft: #262a4a;
    --accent-contrast: #14151f;
    --success: #4ade80;
    --success-soft: #123321;
    --warn: #fbbf24;
    --warn-soft: #3a2a0c;
    --danger: #f87171;
    --danger-soft: #3a1616;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.2), 0 8px 24px rgba(0, 0, 0, 0.35);
  }
}

:root[data-theme="dark"] {
  --bg: #14151f;
  --bg-elevated: #1c1e2b;
  --text: #eceef7;
  --text-muted: #9a9db3;
  --border: #2b2d3d;
  --accent: #8385f5;
  --accent-soft: #262a4a;
  --accent-contrast: #14151f;
  --success: #4ade80;
  --success-soft: #123321;
  --warn: #fbbf24;
  --warn-soft: #3a2a0c;
  --danger: #f87171;
  --danger-soft: #3a1616;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.2), 0 8px 24px rgba(0, 0, 0, 0.35);
}
:root[data-theme="light"] {
  --bg: #f5f6fb;
  --bg-elevated: #ffffff;
  --text: #1c1e2b;
  --text-muted: #5b5f77;
  --border: #e3e5f0;
  --accent: #6366f1;
  --accent-soft: #eef0fe;
  --accent-contrast: #ffffff;
  --success: #16a34a;
  --success-soft: #e8f7ee;
  --warn: #d97706;
  --warn-soft: #fef3e2;
  --danger: #dc2626;
  --danger-soft: #fde8e8;
  --shadow: 0 1px 2px rgba(20, 20, 43, 0.04), 0 8px 24px rgba(20, 20, 43, 0.06);
}

* { box-sizing: border-box; }
html, body { max-width: 100%; overflow-x: hidden; }

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 0.4em; }
p { margin: 0 0 0.8em; }
a { color: var(--accent); }

/* ---------- Topbar ---------- */
.topbar {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 14px 24px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
  flex-wrap: wrap;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 40px; height: 40px;
  display: flex; align-items: center; justify-content: center;
  background: var(--accent); color: var(--accent-contrast);
  border-radius: 10px; font-weight: 700; font-size: 20px; flex-shrink: 0;
}
.brand-text h1 { font-size: 17px; font-weight: 700; }
.brand-text p { margin: 0; font-size: 12px; color: var(--text-muted); }

.tabs {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  margin-left: auto;
}
.tab-btn {
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 13.5px;
  font-weight: 600;
  padding: 9px 14px;
  border-radius: 999px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s;
}
.tab-btn:hover { background: var(--accent-soft); color: var(--text); }
.tab-btn.active { background: var(--accent); color: var(--accent-contrast); }

.menu-toggle { display: none; background: none; border: none; font-size: 22px; color: var(--text); cursor: pointer; }

@media (max-width: 860px) {
  .tabs { display: none; width: 100%; order: 3; }
  .tabs.open { display: flex; }
  .menu-toggle { display: block; margin-left: auto; }
  .topbar { padding: 12px 16px; }
}

/* ---------- Layout ---------- */
.view {
  max-width: 980px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}
.footer {
  text-align: center;
  font-size: 11.5px;
  color: var(--text-muted);
  padding: 20px;
  border-top: 1px solid var(--border);
}

.section-head { margin-bottom: 18px; }
.section-head h2 { font-size: 22px; }
.section-head p { color: var(--text-muted); font-size: 14px; }

.card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  margin-bottom: 16px;
}

.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 14px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  font-size: 13.5px;
  font-weight: 600;
  padding: 9px 16px;
  border-radius: 999px;
  cursor: pointer;
  transition: transform 0.1s, background 0.15s;
}
.btn:hover { background: var(--accent-soft); }
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--accent); color: var(--accent-contrast); border-color: transparent; }
.btn-primary:hover { filter: brightness(1.08); background: var(--accent); }
.btn-ghost { border-color: transparent; background: transparent; }
.btn-sm { padding: 6px 12px; font-size: 12.5px; }
.btn-row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }

/* ---------- Badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  white-space: nowrap;
}

/* ---------- Progress bars ---------- */
.progress-track {
  background: var(--border);
  border-radius: 999px;
  height: 8px;
  overflow: hidden;
  flex: 1;
}
.progress-fill { height: 100%; background: var(--accent); border-radius: 999px; transition: width 0.3s; }
.progress-row { display: flex; align-items: center; gap: 10px; font-size: 12.5px; color: var(--text-muted); }
.progress-row .progress-track { min-width: 60px; }

/* ---------- Home ---------- */
.stat-tile {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
}
.stat-tile .num { font-size: 26px; font-weight: 800; color: var(--accent); }
.stat-tile .label { font-size: 12px; color: var(--text-muted); margin-top: 2px; }

.tip-list { list-style: none; padding: 0; margin: 0; }
.tip-list li {
  padding: 10px 0;
  border-bottom: 1px dashed var(--border);
  font-size: 13.5px;
  display: flex;
  gap: 10px;
}
.tip-list li:last-child { border-bottom: none; }
.tip-list li::before { content: "\2022"; color: var(--accent); font-weight: 900; }

/* ---------- Plan ---------- */
.area-card { margin-bottom: 14px; }
.area-head {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  cursor: pointer;
}
.area-head h3 { font-size: 16px; }
.area-head .meta { font-size: 12px; color: var(--text-muted); }
.area-objetivo { font-size: 13px; color: var(--text-muted); margin: 8px 0 0; }
.module { margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--border); }
.module h4 { font-size: 13.5px; color: var(--accent); margin-bottom: 8px; }
.item-row { display: flex; align-items: flex-start; gap: 10px; padding: 5px 0; font-size: 13.5px; }
.item-row input[type=checkbox] { margin-top: 3px; flex-shrink: 0; width: 16px; height: 16px; accent-color: var(--accent); cursor: pointer; }
.item-row label { cursor: pointer; }
.item-row.checked label { color: var(--text-muted); text-decoration: line-through; }
.area-body { display: none; }
.area-body.open { display: block; }
.chevron { transition: transform 0.15s; color: var(--text-muted); }
.chevron.open { transform: rotate(90deg); }

/* ---------- Flashcards ---------- */
.fc-toolbar { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-bottom: 16px; }
.fc-select { padding: 8px 12px; border-radius: 999px; border: 1px solid var(--border); background: var(--bg-elevated); color: var(--text); font-size: 13px; font-weight: 600; }
.fc-counter { font-size: 12.5px; color: var(--text-muted); margin-left: auto; }

.flash-stage { perspective: 1400px; max-width: 640px; margin: 0 auto; }
.flash-card {
  position: relative;
  min-height: 260px;
  border-radius: var(--radius);
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 0.5s cubic-bezier(.4,.2,.2,1);
}
.flash-card.flipped { transform: rotateY(180deg); }
.flash-face {
  position: absolute; inset: 0;
  backface-visibility: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  background: var(--bg-elevated);
  padding: 28px;
  display: flex; flex-direction: column;
  overflow-y: auto;
}
.flash-face .face-label { font-size: 11px; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-muted); font-weight: 700; margin-bottom: 10px; }
.flash-face .face-text { font-size: 17px; font-weight: 600; flex: 1; }
.flash-back { transform: rotateY(180deg); }
.flash-back .face-text { font-size: 14.5px; font-weight: 400; color: var(--text); }
.flash-hint { text-align: center; font-size: 12px; color: var(--text-muted); margin-top: 10px; }

.fc-rate-row { display: flex; gap: 10px; justify-content: center; margin-top: 18px; }
.fc-rate-btn { flex: 1; max-width: 180px; padding: 12px; border-radius: var(--radius-sm); border: none; font-weight: 700; font-size: 13.5px; cursor: pointer; }
.fc-rate-btn.hard { background: var(--danger-soft); color: var(--danger); }
.fc-rate-btn.ok { background: var(--warn-soft); color: var(--warn); }
.fc-rate-btn.easy { background: var(--success-soft); color: var(--success); }

.fc-empty { text-align: center; padding: 60px 20px; color: var(--text-muted); }

/* ---------- Quiz ---------- */
.quiz-progress { margin-bottom: 18px; }
.quiz-q { font-size: 17px; font-weight: 700; margin-bottom: 18px; }
.quiz-options { display: flex; flex-direction: column; gap: 10px; }
.quiz-option {
  text-align: left;
  padding: 13px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  font-size: 14px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.quiz-option:hover { border-color: var(--accent); }
.quiz-option.selected { border-color: var(--accent); background: var(--accent-soft); }
.quiz-option.correct { border-color: var(--success); background: var(--success-soft); color: var(--success); font-weight: 700; }
.quiz-option.incorrect { border-color: var(--danger); background: var(--danger-soft); color: var(--danger); font-weight: 700; }
.quiz-option:disabled { cursor: default; }
.quiz-explain { margin-top: 16px; padding: 14px; background: var(--accent-soft); border-radius: var(--radius-sm); font-size: 13.5px; }
.quiz-result { text-align: center; padding: 30px 10px; }
.quiz-result .score { font-size: 42px; font-weight: 800; color: var(--accent); }

/* ---------- Banco ---------- */
.bank-toolbar { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 16px; align-items: center; }
.bank-search { flex: 1; min-width: 200px; padding: 9px 14px; border-radius: 999px; border: 1px solid var(--border); background: var(--bg-elevated); color: var(--text); font-size: 13.5px; }
.bank-item { padding: 12px 0; border-bottom: 1px solid var(--border); display: flex; gap: 12px; align-items: flex-start; }
.bank-item:last-child { border-bottom: none; }
.bank-item input[type=checkbox] { margin-top: 4px; width: 16px; height: 16px; accent-color: var(--success); cursor: pointer; flex-shrink: 0; }
.bank-item .bq-num { font-size: 11px; color: var(--text-muted); font-weight: 700; min-width: 34px; }
.bank-item .bq-text { flex: 1; font-size: 13.5px; }
.bank-item.done .bq-text { color: var(--text-muted); }
.bank-actions { display: flex; gap: 14px; margin-top: 6px; }
.bank-note-toggle { font-size: 11.5px; color: var(--accent); background: none; border: none; cursor: pointer; padding: 0; font-weight: 600; }
.bank-answer {
  display: none; margin-top: 8px; padding: 10px 12px; border-radius: 8px;
  background: var(--success-soft); color: var(--text); font-size: 12.5px; line-height: 1.55;
}
.bank-answer.open { display: block; }
.bank-answer-label { display: block; font-size: 10.5px; text-transform: uppercase; letter-spacing: 0.04em; color: var(--success); font-weight: 800; margin-bottom: 4px; }
.bank-note {
  width: 100%; margin-top: 8px; border: 1px solid var(--border); border-radius: 8px;
  background: var(--bg); color: var(--text); font-size: 12.5px; padding: 8px; resize: vertical; min-height: 34px;
  font-family: inherit; display: none;
}
.bank-note.open { display: block; }

.bank-group { margin-bottom: 10px; }
.bank-group-head {
  display: flex; align-items: center; gap: 10px; padding: 12px 4px;
  cursor: pointer; user-select: none;
}
.bank-group-head h3 { font-size: 15px; margin: 0; }
.bank-group-count { margin-left: auto; font-size: 12px; color: var(--text-muted); font-weight: 700; }
.bank-group-body { display: none; }
.bank-group-body.open { display: block; }

/* ---------- Progreso ---------- */
.prog-row { display: flex; align-items: center; gap: 14px; padding: 10px 0; border-bottom: 1px solid var(--border); }
.prog-row:last-child { border-bottom: none; }
.prog-row .prog-label { width: 190px; flex-shrink: 0; font-size: 13.5px; font-weight: 600; }
.prog-row .prog-pct { width: 44px; text-align: right; font-size: 12.5px; color: var(--text-muted); font-weight: 700; }

.empty-note { text-align: center; color: var(--text-muted); font-size: 13px; padding: 20px; }

@media (max-width: 600px) {
  .prog-row { flex-wrap: wrap; }
  .prog-row .prog-label { width: 100%; }
  .flash-face { padding: 20px; }
  .flash-face .face-text { font-size: 15px; }
}