:root {
  --ink: #1d2430;
  --muted: #667085;
  --line: #d9dee7;
  --panel: #ffffff;
  --soft: #f4f7fb;
  --brand: #176b87;
  --brand-dark: #0e5269;
  --accent: #c95f35;
  --good: #16724f;
  --bad: #b42318;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--soft);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: center;
  padding: 24px clamp(18px, 4vw, 48px);
  background: #fff;
  border-bottom: 1px solid var(--line);
}

h1,
h2,
h3,
p {
  margin: 0;
}

h1 {
  font-size: clamp(24px, 3vw, 36px);
  line-height: 1.1;
}

h2 {
  font-size: 20px;
  margin-bottom: 18px;
}

h3 {
  font-size: 16px;
}

.eyebrow {
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
  margin-bottom: 4px;
}

.session-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

main {
  padding: 28px clamp(18px, 4vw, 48px) 48px;
}

.auth-shell {
  min-height: 62vh;
  display: grid;
  place-items: center;
}

.auth-panel {
  width: min(100%, 420px);
}

.panel-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(280px, 1fr));
  gap: 20px;
  align-items: start;
  margin-bottom: 20px;
}

.panel,
.question-card,
.exam {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.panel,
.exam {
  padding: 22px;
}

.stack {
  display: grid;
  gap: 12px;
}

label {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-size: 14px;
  margin-bottom: 16px;
}

input,
select,
button {
  font: inherit;
}

input,
select {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
  min-height: 42px;
  padding: 0 12px;
}

button {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  min-height: 42px;
  padding: 0 14px;
  cursor: pointer;
}

button:hover {
  border-color: var(--brand);
}

.primary {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

.split-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: start;
  margin-bottom: 18px;
}

.assignment,
.notice {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px;
  background: #fff;
}

.assignment {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
}

.muted,
.meta {
  color: var(--muted);
  font-size: 14px;
}

.badge,
.score {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 34px;
  border-radius: 8px;
  padding: 0 10px;
  font-weight: 800;
}

.badge {
  background: #eef6f8;
  color: var(--brand-dark);
}

.score {
  min-width: 88px;
  background: var(--brand-dark);
  color: #fff;
}

.exam {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}

.question-card {
  padding: 18px;
}

.question-card legend {
  padding: 0 8px;
  font-weight: 700;
}

.options {
  display: grid;
  gap: 10px;
  margin-top: 12px;
}

.option {
  display: grid;
  grid-template-columns: 28px 1fr;
  gap: 10px;
  align-items: start;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px;
  color: var(--ink);
  margin: 0;
}

.option input {
  min-height: 18px;
  margin-top: 2px;
}

.correct {
  border-color: var(--good);
  background: #ecfdf3;
}

.incorrect,
.error {
  border-color: var(--bad);
  background: #fff1f0;
}

.error,
.form-message {
  color: var(--bad);
  border: 1px solid var(--bad);
  border-radius: 8px;
  padding: 10px;
  margin-top: 12px;
}

.form-message.success {
  color: var(--good);
  border-color: var(--good);
  background: #ecfdf3;
}

.hidden {
  display: none;
}

@media (max-width: 820px) {
  .topbar,
  .split-header {
    flex-direction: column;
    align-items: stretch;
  }

  .panel-grid,
  .assignment {
    grid-template-columns: 1fr;
  }
}