.itap-app {
  --itap-ink: #14213d;
  --itap-muted: #65748b;
  --itap-line: #dbe3ee;
  --itap-blue: #1565d8;
  --itap-blue-soft: #eef6ff;
  --itap-green: #087a4b;
  --itap-red: #b42318;
  --itap-amber: #a15c00;
  max-width: 860px;
  margin: 0 auto;
  padding: 24px 16px 48px;
  color: var(--itap-ink);
  font-family: inherit;
}
.itap-app * {
  box-sizing: border-box;
}
.itap-title-row {
  display: flex;
  align-items: center;
  gap: 10px;
}
.itap-header h2 {
  margin: 0;
  font-size: 1.75rem;
  line-height: 1.2;
}
.itap-subtitle {
  margin: 7px 0 22px;
  color: var(--itap-muted);
}
.itap-badge {
  border-radius: 99px;
  padding: 3px 9px;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.itap-badge-free {
  color: var(--itap-green);
  background: #eafaf2;
}
.itap-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-bottom: 18px;
}
.itap-select {
  min-height: 38px;
  padding: 7px 28px 7px 10px;
  border: 1px solid var(--itap-line);
  border-radius: 8px;
  background: #fff;
  color: var(--itap-ink);
}
.itap-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 38px;
  padding: 8px 14px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-weight: 650;
  font-size: 0.9rem;
  cursor: pointer;
  text-decoration: none;
  transition: 0.15s;
}
.itap-btn-primary {
  background: var(--itap-blue);
  color: #fff;
}
.itap-btn-primary:hover {
  background: #0d55b7;
}
.itap-btn-ghost {
  border-color: var(--itap-line);
  color: var(--itap-ink);
  background: #fff;
}
.itap-btn-ghost:hover {
  background: #f6f8fb;
}
.itap-loading,
.itap-empty {
  text-align: center;
  padding: 32px 16px;
  color: var(--itap-muted);
}
.itap-card {
  border: 1px solid var(--itap-line);
  border-radius: 14px;
  overflow: hidden;
  background: #fff;
  box-shadow: 0 2px 8px rgba(20, 33, 61, 0.04);
  margin-bottom: 16px;
}
.itap-card-head {
  padding: 15px 18px;
  border-bottom: 1px solid var(--itap-line);
  background: #fbfcfe;
}
.itap-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 12px;
}
.itap-tag {
  display: inline-block;
  padding: 3px 8px;
  border-radius: 6px;
  background: #edf3fc;
  color: #28598e;
  font-size: 0.74rem;
  font-weight: 700;
}
.itap-tag-diff {
  background: #fff6db;
  color: var(--itap-amber);
}
.itap-tag-topic {
  background: #f3efff;
  color: #6543a0;
}
.itap-tag-marks {
  background: #eff8f3;
  color: var(--itap-green);
}
.itap-q {
  font-size: 1.08rem;
  font-weight: 560;
  line-height: 1.65;
}
.itap-q mjx-container {
  margin: 0 !important;
}
.itap-q mjx-frac {
  font-size: 1.16em;
}
.itap-hint {
  margin-top: 12px;
  padding: 9px 11px;
  border-left: 3px solid #e9a91d;
  background: #fff9e9;
  color: #79520b;
  font-size: 0.9rem;
}
.itap-hint mjx-container {
  margin: 0 !important;
}
.itap-input {
  padding: 16px 18px;
}
.itap-text {
  width: 100%;
  resize: vertical;
  padding: 10px 12px;
  border: 1px solid var(--itap-line);
  border-radius: 8px;
  font: inherit;
}
.itap-text:focus {
  outline: 2px solid #b8d7ff;
  border-color: var(--itap-blue);
}
.itap-mc {
  display: grid;
  gap: 8px;
}
.itap-mc-opt {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 10px 12px;
  border: 1px solid var(--itap-line);
  border-radius: 8px;
  cursor: pointer;
}
.itap-mc-opt:hover {
  border-color: #8dbdf8;
  background: #f7fbff;
}
.itap-mc-opt input {
  align-self: center;
  margin: 0;
}
.itap-mc-opt > span {
  display: flex;
  align-items: center;
  min-height: 24px;
}
.itap-mc-opt > span mjx-container {
  margin: 0 !important;
}
.itap-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-top: 14px;
}
.itap-btn-ai { border-color: #b7a6f4; background: #f6f2ff; color: #5138a8; }
.itap-btn-ai:hover { background: #ede5ff; }
.itap-btn-ai:disabled { cursor: wait; opacity: .7; }
.itap-ai-response { margin-top: 14px; padding: 12px 14px; border-left: 4px solid #7453d6; border-radius: 0 8px 8px 0; background: #f7f4ff; color: #3e2e7a; }
.itap-ai-response p { margin: 4px 0 7px; line-height: 1.55; }
.itap-ai-response small { color: #675a95; }
.itap-feedback {
  padding: 0 18px 18px;
}
.itap-verdict {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 12px 14px;
  border-radius: 8px;
  font-weight: 650;
}
.itap-verdict.is-correct {
  background: #eafaf2;
  color: var(--itap-green);
}
.itap-verdict.is-wrong {
  background: #fff0ef;
  color: var(--itap-red);
}
.itap-verdict-mark {
  font-size: 1.25rem;
}
.itap-marks {
  list-style: none;
  margin: 14px 0;
  padding: 0;
}
.itap-marks li {
  display: flex;
  gap: 10px;
  padding: 8px 0;
  border-bottom: 1px dashed var(--itap-line);
  font-size: 0.9rem;
}
.itap-mark-code {
  font-weight: 750;
  min-width: 42px;
}
.itap-marks .is-awarded .itap-mark-code {
  color: var(--itap-green);
}
.itap-marks .is-missed .itap-mark-code {
  color: var(--itap-red);
}
.itap-step-controls {
  margin: 16px 0 10px;
}
.itap-step {
  margin: 10px 0;
  padding: 12px 14px;
  border-left: 4px solid var(--itap-blue);
  border-radius: 0 8px 8px 0;
  background: var(--itap-blue-soft);
  animation: itap-in 0.2s ease-out;
}
.itap-step-no {
  color: var(--itap-blue);
  font-size: 0.72rem;
  font-weight: 750;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.itap-step-title {
  margin-top: 2px;
  font-weight: 700;
}
.itap-step-eq {
  overflow-x: auto;
  margin: 10px 0;
  text-align: center;
  font-size: 1.07rem;
}
.itap-step-eq mjx-container {
  margin: 0.3em auto !important;
}
.itap-step-why {
  color: #536274;
  font-size: 0.92rem;
}
.itap-final {
  margin: 14px 0;
  padding: 13px 15px;
  border: 1px solid #9ce0bd;
  border-radius: 9px;
  background: #edfcf3;
}
.itap-final-label {
  display: block;
  margin-bottom: 4px;
  color: var(--itap-green);
  font-size: 0.72rem;
  font-weight: 750;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.itap-final-value {
  font-size: 1.1rem;
  font-weight: 650;
}
.itap-callouts {
  display: grid;
  gap: 10px;
  margin-top: 16px;
}
.itap-callout {
  padding: 11px 13px;
  border-left: 4px solid;
  border-radius: 0 8px 8px 0;
  font-size: 0.92rem;
}
.itap-callout strong {
  display: block;
  margin-bottom: 3px;
}
.itap-callout p {
  margin: 0;
}
.itap-callout-key {
  border-color: var(--itap-blue);
  background: #eef6ff;
}
.itap-callout-mistake {
  border-color: var(--itap-red);
  background: #fff1ef;
}
.itap-callout-tip {
  border-color: #d99513;
  background: #fff9e7;
}
.itap-daily {
  margin-top: 16px;
  color: var(--itap-muted);
  font-size: 0.85rem;
}
.itap-upsell {
  margin-top: 30px;
  padding: 1px;
  border-radius: 15px;
  background: linear-gradient(120deg, #cae4ff, #dacdff);
}
.itap-upsell-inner {
  display: flex;
  gap: 18px;
  align-items: center;
  justify-content: space-between;
  padding: 22px;
  border-radius: 14px;
  background: #f9fcff;
}
.itap-upsell p {
  margin: 5px 0 0;
  color: var(--itap-muted);
  font-size: 0.92rem;
}
@keyframes itap-in {
  from {
    opacity: 0;
    transform: translateY(5px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}
@media (max-width: 600px) {
  .itap-app {
    padding: 18px 12px 34px;
  }
  .itap-header h2 {
    font-size: 1.45rem;
  }
  .itap-select {
    flex: 1;
  }
  .itap-upsell-inner {
    align-items: flex-start;
    flex-direction: column;
  }
  .itap-upsell-inner .itap-btn {
    width: 100%;
  }
}