:root {
  --bg: #ffffff;
  --ink: #111827;
  --muted: #667085;
  --soft: #f7f8fa;
  --line: #dfe3ea;
  --line-strong: #c8ced8;
  --blue: #1463ff;
  --blue-dark: #0d46bf;
  --green: #19a66a;
  --red: #d94747;
  --shadow: 0 18px 42px rgba(17, 24, 39, 0.08);
  --radius: 8px;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--bg);
}

body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(245, 247, 251, 0.9), #fff 280px),
    var(--bg);
  font-family: Inter, "SF Pro Display", "Segoe UI", Arial, "Microsoft YaHei", sans-serif;
  line-height: 1.5;
  letter-spacing: 0;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.hidden {
  display: none !important;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  min-height: 58px;
  padding: 0 28px;
  border-bottom: 1px solid rgba(223, 227, 234, 0.86);
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: blur(18px);
}

.brand,
.nav a {
  color: inherit;
  text-decoration: none;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  width: fit-content;
  font-size: 15px;
  font-weight: 700;
}

.brand-mark {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: var(--blue);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.38);
}

.nav {
  display: flex;
  align-items: center;
  gap: 24px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

.nav a {
  position: relative;
  padding: 18px 0;
}

.nav a[aria-current="page"] {
  color: var(--blue);
}

.nav a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: var(--blue);
}

.user-chip {
  justify-self: end;
  color: var(--muted);
  font-size: 13px;
}

.shell {
  width: min(100% - 44px, 1220px);
  margin: 0 auto;
  padding: 46px 0 68px;
}

.hero {
  text-align: center;
}

.hero h1 {
  margin: 0;
  font-size: clamp(40px, 6vw, 64px);
  line-height: 1.08;
  font-weight: 780;
  letter-spacing: 0;
}

.hero p {
  max-width: 720px;
  margin: 14px auto 0;
  color: var(--muted);
  font-size: 17px;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  margin-top: 34px;
}

.mode-card {
  min-height: 116px;
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr) auto;
  gap: 18px;
  align-items: center;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.92);
  color: var(--ink);
  text-align: left;
  box-shadow: 0 10px 26px rgba(17, 24, 39, 0.04);
}

.mode-card:hover,
.mode-card.is-active {
  border-color: var(--blue);
  box-shadow: var(--shadow);
}

.mode-icon {
  color: var(--blue);
}

.mode-icon svg {
  width: 46px;
  height: 46px;
  display: block;
  fill: currentColor;
}

.mode-card strong {
  display: block;
  font-size: 18px;
}

.mode-card small {
  display: block;
  margin-top: 4px;
  color: var(--muted);
  font-size: 14px;
}

.mode-card i {
  color: var(--muted);
  font-size: 30px;
  font-style: normal;
  line-height: 1;
}

.workspace {
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr) 280px;
  gap: 24px;
  align-items: start;
  margin-top: 28px;
}

.stats-panel,
.quiz-panel,
.identity-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 12px 30px rgba(17, 24, 39, 0.05);
}

.stats-panel,
.identity-panel {
  padding: 18px;
}

.panel-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.panel-head h2 {
  margin: 0;
  font-size: 17px;
}

.panel-head span {
  color: var(--muted);
  font-size: 12px;
}

.score-ring {
  --score: 0;
  width: 138px;
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  margin: 28px auto;
  border-radius: 50%;
  background:
    radial-gradient(circle at center, #fff 58%, transparent 59%),
    conic-gradient(var(--blue) calc(var(--score) * 1%), #eef1f5 0);
}

.score-ring span,
.score-ring small {
  grid-area: 1 / 1;
}

.score-ring span {
  font-size: 28px;
  font-weight: 780;
}

.score-ring small {
  transform: translateY(29px);
  color: var(--muted);
  font-size: 12px;
}

.metrics {
  margin: 0;
}

.metrics div {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 0;
  border-top: 1px solid var(--line);
}

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

.metrics dd {
  margin: 0;
  font-weight: 750;
}

.quiz-panel {
  min-height: 500px;
  padding: 22px;
}

.quiz-top {
  display: flex;
  justify-content: space-between;
  color: #475467;
  font-size: 14px;
  font-weight: 700;
}

.progress-track {
  height: 6px;
  margin-top: 10px;
  overflow: hidden;
  border-radius: 999px;
  background: #edf1f6;
}

.progress-track span {
  display: block;
  width: 0%;
  height: 100%;
  border-radius: inherit;
  background: var(--blue);
  transition: width 0.24s ease;
}

.empty-state,
.finish-card {
  min-height: 380px;
  display: grid;
  place-content: center;
  text-align: center;
}

.empty-state h2,
.finish-card h2,
.section-title h2,
.question-card h2 {
  margin: 0;
  letter-spacing: 0;
}

.empty-state p,
.finish-card p {
  max-width: 420px;
  margin: 10px auto 0;
  color: var(--muted);
}

.section-title {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: center;
  margin-top: 26px;
}

.section-title h2 {
  font-size: 22px;
}

input {
  min-height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0 12px;
  background: #fff;
  color: var(--ink);
  outline: none;
}

input:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(20, 99, 255, 0.12);
}

.industry-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 18px;
}

.industry-button {
  min-height: 68px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 12px;
  background: #fff;
  color: var(--ink);
  text-align: left;
}

.industry-button:hover {
  border-color: var(--blue);
}

.industry-button strong {
  font-size: 14px;
}

.industry-button span {
  color: var(--muted);
  font-size: 12px;
}

.question-card {
  padding-top: 46px;
}

.stock-label {
  width: fit-content;
  margin: 0 auto 8px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 760;
}

.question-card h2 {
  text-align: center;
  font-size: clamp(28px, 4vw, 38px);
  line-height: 1.2;
}

.question-card p {
  margin: 10px 0 0;
  color: var(--muted);
  text-align: center;
}

.option-list {
  display: grid;
  gap: 10px;
  margin-top: 26px;
}

.option-button {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 12px;
  align-items: center;
  min-height: 52px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 11px 13px;
  background: #fff;
  color: var(--ink);
  text-align: left;
}

.option-button:hover {
  border-color: var(--line-strong);
  background: var(--soft);
}

.option-button span:first-child {
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: #eef3ff;
  color: #23406f;
  font-size: 13px;
  font-weight: 760;
}

.option-button.is-correct {
  border-color: rgba(25, 166, 106, 0.55);
  background: rgba(25, 166, 106, 0.08);
}

.option-button.is-wrong {
  border-color: rgba(217, 71, 71, 0.55);
  background: rgba(217, 71, 71, 0.08);
}

.quiz-actions,
.finish-actions {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  margin-top: 22px;
}

.primary-button,
.secondary-button {
  min-height: 42px;
  border-radius: 8px;
  padding: 0 18px;
  font-size: 14px;
  font-weight: 740;
}

.primary-button {
  border: 1px solid var(--blue);
  background: var(--blue);
  color: #fff;
}

.primary-button:hover {
  background: var(--blue-dark);
}

.primary-button:disabled {
  cursor: not-allowed;
  border-color: #d8dde6;
  background: #d8dde6;
}

.secondary-button {
  border: 1px solid var(--line-strong);
  background: #fff;
  color: #344054;
}

.secondary-button:hover {
  border-color: #98a2b3;
}

.answer-note {
  min-height: 22px;
  color: var(--muted);
  font-size: 14px;
}

.identity-panel p {
  margin: 14px 0;
  color: var(--muted);
  font-size: 14px;
}

.identity-panel label {
  display: block;
  margin-bottom: 7px;
  color: #475467;
  font-size: 13px;
  font-weight: 740;
}

.username-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px;
}

.status-line {
  min-height: 22px;
}

.status-line.is-ok {
  color: var(--green);
}

.status-line.is-error {
  color: var(--red);
}

@media (max-width: 1060px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .stats-panel {
    display: none;
  }

  .identity-panel {
    order: -1;
  }
}

@media (max-width: 860px) {
  .topbar {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 14px 18px;
  }

  .nav {
    justify-content: flex-start;
  }

  .user-chip {
    justify-self: start;
  }

  .mode-grid,
  .industry-grid {
    grid-template-columns: 1fr;
  }

  .shell {
    width: min(100% - 28px, 1220px);
    padding-top: 32px;
  }
}

@media (max-width: 560px) {
  .mode-card {
    grid-template-columns: 40px minmax(0, 1fr);
  }

  .mode-card i {
    display: none;
  }

  .quiz-panel {
    padding: 16px;
  }

  .section-title,
  .quiz-actions,
  .finish-actions,
  .username-row {
    flex-direction: column;
    display: flex;
    align-items: stretch;
  }
}