:root {
  --bg: #ffffff;
  --panel: #ffffff;
  --panel-alt: #f5f5f5;
  --border: #e2e2e2;
  --text: #0a0a0a;
  --text-dim: #6b6b6b;
  --ink: #0a0a0a;
  --ink-soft: #f0f0f0;
  --header-bg: #0a0a0a;
  --header-text: #ffffff;
  --correct: #16794f;
  --correct-bg: #eaf6ef;
  --incorrect: #b3261e;
  --incorrect-bg: #fbeceb;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);

  /* paleta da tela inicial */
  --brand-green: #0f9b4e;
  --brand-green-dark: #0c7d3f;
  --brand-yellow: #ffcc29;
  --brand-blue: #1a3d8f;
  --sunset-deep: #241b3d;
  --sunset-mid: #6d3564;
  --sunset-warm: #d9713f;
  --sunset-glow: #ffb347;
  --brand-flag: linear-gradient(90deg, #0f9b4e 0%, #0f9b4e 33%, #ffcc29 33%, #ffcc29 66%, #1a3d8f 66%, #1a3d8f 100%);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, Roboto, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

#app {
  display: grid;
  grid-template-columns: 292px 1fr;
  grid-template-rows: auto 1fr;
  min-height: 100vh;
  background: #fbfaf9;
}

header.top {
  grid-column: 1 / -1;
  background: linear-gradient(105deg, var(--sunset-deep) 0%, var(--sunset-mid) 58%, var(--sunset-warm) 100%);
  color: var(--header-text);
  padding: 0;
}

.top-inner {
  padding: 15px 28px;
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 36px;
  height: 25px;
  border-radius: 4px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  flex-shrink: 0;
  display: block;
}

.brand-text { display: flex; flex-direction: column; gap: 1px; }

header.top h1 {
  font-size: 18px;
  margin: 0;
  font-weight: 800;
  letter-spacing: -0.015em;
}

header.top .tag {
  font-size: 12px;
  opacity: 0.7;
}

.brand-stripe {
  height: 3px;
  background: var(--brand-flag);
}

.user-bar {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
}
.user-bar #user-email { opacity: 0.8; }
.user-bar #logout-btn {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.28);
  color: white;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12.5px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.14s;
}
.user-bar #logout-btn:hover { background: rgba(255, 255, 255, 0.24); }

.welcome-screen {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  background: #160f22;
}

.welcome-hero {
  width: 100%;
  line-height: 0;
}

.welcome-illustration {
  width: 100%;
  height: auto;
  max-height: 42vh;
  display: block;
}

.welcome-card {
  width: 100%;
  max-width: 480px;
  margin: -36px 20px 40px;
  background: var(--panel);
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
  padding: 36px 30px 30px;
  text-align: center;
  position: relative;
  z-index: 1;
  overflow: hidden;
}

.welcome-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: var(--brand-flag);
}

.welcome-card h1 {
  margin: 0 0 6px;
  font-size: 26px;
  letter-spacing: -0.01em;
}

.welcome-tagline {
  margin: 0 0 20px;
  font-size: 14.5px;
  color: var(--text-dim);
}

.welcome-list {
  list-style: none;
  margin: 0 0 26px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: left;
}

.welcome-list li {
  font-size: 13.8px;
  line-height: 1.5;
  color: var(--text);
  padding-left: 22px;
  position: relative;
}

.welcome-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 0;
  color: #0f9b4e;
  font-weight: 700;
}

.welcome-btn.primary {
  width: 100%;
  background: #0f9b4e;
}
.welcome-btn.primary:hover { background: #0c7d3f; opacity: 1; }

@media (max-width: 560px) {
  .welcome-card { margin-top: -24px; }
}

.auth-screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(160deg, #241b3d 0%, #6d3564 45%, #d9713f 85%, #ffb347 130%);
  padding: 20px;
}

.auth-card {
  width: 100%;
  max-width: 360px;
  background: var(--panel);
  border: none;
  border-radius: 20px;
  padding: 36px 30px 30px;
  box-shadow: 0 20px 50px rgba(22, 15, 34, 0.35);
  display: flex;
  flex-direction: column;
  gap: 11px;
  position: relative;
  overflow: hidden;
}

.auth-stripe {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: var(--brand-flag);
}

.auth-card h1 {
  margin: 10px 0 2px;
  font-size: 24px;
  text-align: center;
  background: linear-gradient(90deg, #0f9b4e, #1a3d8f);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.auth-sub {
  margin: 0 0 10px;
  font-size: 13px;
  color: var(--text-dim);
  text-align: center;
}

.auth-error {
  font-size: 13px;
  color: var(--incorrect);
  background: var(--incorrect-bg);
  padding: 8px 10px;
  border-radius: 8px;
}

.auth-success {
  font-size: 13px;
  color: var(--correct);
  background: var(--correct-bg);
  padding: 8px 10px;
  border-radius: 8px;
}

.link-btn {
  background: transparent;
  border: none;
  color: var(--text-dim);
  font-size: 12.5px;
  text-decoration: underline;
  cursor: pointer;
  padding: 2px 0;
  align-self: center;
}
.link-btn:hover { color: #1a3d8f; }

.auth-links-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  margin: 2px 0 4px;
}
.auth-links-row .link-btn { align-self: auto; }

.auth-card input {
  font-size: 14px;
  padding: 11px 13px;
  border: 1.5px solid var(--border);
  border-radius: 10px;
  font-family: inherit;
  color: var(--text);
  transition: border-color 0.12s, box-shadow 0.12s;
}
.auth-card input:focus {
  outline: none;
  border-color: #0f9b4e;
  box-shadow: 0 0 0 3px rgba(15, 155, 78, 0.15);
}

.auth-btn {
  width: 100%;
  text-align: center;
}

.auth-card button.primary.auth-btn {
  background: linear-gradient(90deg, #0f9b4e, #0c8f6b);
  margin-top: 4px;
}
.auth-card button.primary.auth-btn:hover { opacity: 0.9; }

.auth-divider {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-dim);
  font-size: 12px;
  margin: 4px 0;
}
.auth-divider::before, .auth-divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--border);
}

.google-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--panel);
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
}
.google-btn:hover { background: var(--ink-soft); }
.google-btn::before {
  content: "G";
  font-weight: 800;
  color: var(--text-dim);
  border: 1px solid var(--border);
  border-radius: 50%;
  width: 20px;
  height: 20px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
}

aside.filters {
  border-right: 1px solid var(--border);
  background: var(--panel);
  padding: 18px 16px 24px;
  overflow-y: auto;
  max-height: calc(100vh - 61px);
}

.filter-group {
  background: #fbfaf9;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 13px 13px 11px;
  margin-bottom: 12px;
}

.filter-head {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 9px;
}

aside.filters h2 {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 800;
  color: var(--text-dim);
  margin: 0;
}

.filter-badge {
  margin-left: auto;
  font-size: 11px;
  font-weight: 700;
  min-width: 20px;
  text-align: center;
  padding: 2px 7px;
  border-radius: 20px;
  background: var(--ink-soft);
  color: var(--text-dim);
  transition: background 0.14s, color 0.14s;
}
.filter-badge.on { background: var(--brand-green); color: white; }

.filter-actions {
  display: flex;
  gap: 7px;
  margin-bottom: 8px;
}

.filter-actions button {
  flex: 1;
  font-size: 11.5px;
  font-weight: 600;
  padding: 5px 6px;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: 20px;
  cursor: pointer;
  color: var(--text-dim);
  transition: border-color 0.12s, color 0.12s, background 0.12s;
}
.filter-actions button:hover {
  border-color: var(--brand-green);
  color: var(--brand-green);
  background: rgba(15, 155, 78, 0.07);
}

.check-list {
  display: flex;
  flex-direction: column;
  gap: 1px;
  max-height: 240px;
  overflow-y: auto;
  padding-right: 3px;
}

.check-item {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 13px;
  padding: 6px 7px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.12s;
}
.check-item:hover { background: rgba(15, 155, 78, 0.08); }
.check-item.muted { opacity: 0.38; }
.check-item input {
  accent-color: var(--brand-green);
  width: 15px;
  height: 15px;
  cursor: pointer;
  flex-shrink: 0;
}
.check-item .count {
  margin-left: auto;
  color: var(--text-dim);
  font-size: 11.5px;
  font-variant-numeric: tabular-nums;
}

main.content {
  padding: 28px 32px 60px;
  max-width: 900px;
  width: 100%;
  margin: 0 auto;
}

.sync-error {
  font-size: 13px;
  color: var(--incorrect);
  background: var(--incorrect-bg);
  padding: 10px 14px;
  border-radius: 10px;
  margin-bottom: 14px;
}

.stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}

.stat-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 13px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow);
}
.stat-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
}
.stat-card.accent-green::before { background: var(--brand-green); }
.stat-card.accent-yellow::before { background: var(--brand-yellow); }
.stat-card.accent-blue::before { background: var(--brand-blue); }

.stat-label {
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  font-weight: 700;
  color: var(--text-dim);
}

.stat-value {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.3;
}

.stat-value.score {
  display: flex;
  gap: 12px;
  font-size: 14px;
}
.stat-value.score .ok { color: var(--correct); }
.stat-value.score .bad { color: var(--incorrect); }

.reset-btn {
  margin-top: 4px;
  width: 100%;
  font-size: 12px;
  font-weight: 600;
  padding: 9px 8px;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: 20px;
  cursor: pointer;
  color: var(--text-dim);
  transition: border-color 0.12s, color 0.12s, background 0.12s;
}
.reset-btn:hover {
  border-color: var(--incorrect);
  color: var(--incorrect);
  background: var(--incorrect-bg);
}

.mode-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}

.segmented {
  display: inline-flex;
  background: var(--ink-soft);
  border-radius: 20px;
  padding: 3px;
  gap: 2px;
}
.segmented button {
  font-size: 12.5px;
  font-weight: 600;
  padding: 6px 16px;
  border: none;
  border-radius: 20px;
  background: transparent;
  cursor: pointer;
  color: var(--text-dim);
  transition: background 0.14s, color 0.14s, box-shadow 0.14s;
}
.segmented button.active {
  background: var(--panel);
  color: var(--brand-green);
  box-shadow: var(--shadow);
}
.segmented button:not(.active):hover { color: var(--text); }

.ghost-sm {
  font-size: 12.5px;
  font-weight: 600;
  padding: 7px 16px;
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--panel);
  cursor: pointer;
  color: var(--text-dim);
  transition: border-color 0.12s, color 0.12s, background 0.12s;
}
.ghost-sm:hover {
  border-color: var(--brand-blue);
  color: var(--brand-blue);
  background: rgba(26, 61, 143, 0.06);
}

#empty-state {
  background: var(--panel);
  border: 1px dashed var(--border);
  border-radius: 18px;
  padding: 52px 40px;
  text-align: center;
  color: var(--text-dim);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
#empty-state p { margin: 0; font-size: 14.5px; line-height: 1.55; max-width: 420px; }

.empty-icon {
  width: 62px;
  height: 43px;
  border-radius: 5px;
  box-shadow: var(--shadow);
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 28px 30px;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--brand-flag);
}

.card .meta {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}

.pill {
  font-size: 11.5px;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 20px;
  background: var(--brand-blue);
  color: white;
}
.pill.alt {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text-dim);
  font-weight: 600;
}

.stem {
  font-size: 15.5px;
  line-height: 1.6;
  white-space: pre-wrap;
  margin-bottom: 20px;
}

.q-images {
  display: flex;
  flex-direction: column;
  gap: 3px;
  margin-bottom: 20px;
  background: var(--panel-alt);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 3px;
  overflow: hidden;
}
.q-images img {
  display: block;
  width: 100%;
  max-height: 480px;
  object-fit: contain;
  background: #0a0a0a;
  border-radius: 10px;
}

.options {
  display: flex;
  flex-direction: column;
  gap: 9px;
  margin-bottom: 20px;
}

.option {
  display: flex;
  gap: 13px;
  align-items: flex-start;
  border: 1.5px solid var(--border);
  border-radius: 13px;
  padding: 13px 15px;
  cursor: pointer;
  font-size: 14.5px;
  line-height: 1.45;
  transition: background 0.14s, border-color 0.14s, transform 0.14s;
}
.option:hover {
  border-color: var(--brand-green);
  background: rgba(15, 155, 78, 0.05);
}
.option.selected {
  border-color: var(--brand-green);
  background: rgba(15, 155, 78, 0.09);
}
.option .letter {
  font-weight: 800;
  font-size: 12.5px;
  color: var(--text-dim);
  background: var(--ink-soft);
  width: 24px;
  height: 24px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.14s, color 0.14s;
}
.option:hover .letter,
.option.selected .letter { background: var(--brand-green); color: white; }
.option.answered { cursor: default; transform: none; }
.option.answered:hover { background: transparent; border-color: var(--border); }
.option.answered:hover .letter { background: var(--ink-soft); color: var(--text-dim); }
.option.correct,
.option.answered.correct:hover { border-color: var(--correct); background: var(--correct-bg); }
.option.incorrect,
.option.answered.incorrect:hover { border-color: var(--incorrect); background: var(--incorrect-bg); }
.option.correct .letter,
.option.answered.correct:hover .letter { background: var(--correct); color: white; }
.option.incorrect .letter,
.option.answered.incorrect:hover .letter { background: var(--incorrect); color: white; }
.option .badge {
  margin-left: auto;
  font-size: 10.5px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 20px;
  align-self: center;
  white-space: nowrap;
}
.option.correct .badge { background: var(--correct); color: white; }
.option.incorrect .badge { background: var(--incorrect); color: white; }

.explain {
  border-top: 1px solid var(--border);
  margin-top: 6px;
  padding-top: 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.explain .block {
  font-size: 13.8px;
  line-height: 1.55;
  padding: 14px 16px;
  border-radius: 12px;
  border: 1px solid var(--border);
}
.explain .block.correct-block {
  background: var(--correct-bg);
  border-color: transparent;
  border-left: 4px solid var(--correct);
}
.explain .block.incorrect-block { background: var(--panel-alt); }
.explain .block b { color: var(--ink); }
.explain .block.correct-block b { color: var(--correct); }

.actions-row {
  display: flex;
  justify-content: space-between;
  margin-top: 22px;
  gap: 10px;
}

button.primary {
  background: linear-gradient(90deg, var(--brand-green), #0c8f6b);
  color: white;
  border: none;
  padding: 11px 24px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.12s, box-shadow 0.14s;
  box-shadow: 0 2px 8px rgba(15, 155, 78, 0.25);
}
button.primary:hover { opacity: 0.92; box-shadow: 0 4px 14px rgba(15, 155, 78, 0.32); }
button.primary:disabled {
  opacity: 1;
  cursor: not-allowed;
  background: var(--ink-soft);
  color: var(--text-dim);
  box-shadow: none;
}

button.ghost {
  background: transparent;
  border: 1px solid var(--border);
  padding: 11px 20px;
  border-radius: 20px;
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  color: var(--text-dim);
  transition: border-color 0.12s, color 0.12s, background 0.12s;
}
button.ghost:hover {
  border-color: var(--brand-blue);
  color: var(--brand-blue);
  background: rgba(26, 61, 143, 0.06);
}

.annulled-note {
  font-size: 13.5px;
  color: #8a6414;
  padding: 13px 15px;
  background: rgba(255, 204, 41, 0.14);
  border-radius: 12px;
  border: none;
  border-left: 4px solid var(--brand-yellow);
}

@media (max-width: 900px) {
  .stats-row { grid-template-columns: 1fr; }
}

@media (max-width: 800px) {
  #app { grid-template-columns: 1fr; }
  aside.filters { max-height: none; border-right: none; border-bottom: 1px solid var(--border); }
  main.content { padding: 18px; }
  .card { padding: 22px 18px; }
}