:root {
  --bg: #f5f7fb;
  --card: #ffffff;
  --text: #111827;
  --muted: rgba(17, 24, 39, 0.68);
  --border: rgba(17, 24, 39, 0.12);
  --primary: #2563eb;
  --ok: #16a34a;
  --bad: #dc2626;
  --shadow: 0 10px 30px rgba(17, 24, 39, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji",
    "Segoe UI Emoji";
  background: radial-gradient(1000px 600px at 10% 0%, rgba(37, 99, 235, 0.12), transparent 60%),
    radial-gradient(900px 600px at 90% 10%, rgba(22, 163, 74, 0.08), transparent 55%), var(--bg);
  color: var(--text);
}

a {
  color: var(--primary);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.topbar__inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand {
  text-decoration: none;
  font-weight: 700;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 18px 16px 42px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
  padding: 18px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

@media (max-width: 860px) {
  .grid {
    grid-template-columns: 1fr;
  }
}

.h1 {
  margin: 0 0 16px;
  font-size: 22px;
}

.h2 {
  margin: 0 0 8px;
  font-size: 18px;
}

.stat {
  font-size: 16px;
  color: var(--muted);
  margin: 8px 0 12px;
}

.form {
  display: grid;
  gap: 14px;
}

.field {
  display: grid;
  gap: 8px;
}

.field__label {
  color: var(--muted);
  font-size: 13px;
}

.field__help {
  color: var(--muted);
  font-size: 12px;
}

.input {
  width: 100%;
  padding: 12px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.9);
  color: var(--text);
  outline: none;
}

.muted {
  margin-top: 14px;
  color: var(--muted);
  font-size: 13px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border: 1px solid var(--border);
  padding: 11px 14px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.92);
  color: var(--text);
  cursor: pointer;
  text-decoration: none;
  font-weight: 600;
}

.btn--primary {
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.95), rgba(37, 99, 235, 0.82));
  border-color: rgba(37, 99, 235, 0.28);
  color: #ffffff;
}

.btn--ghost {
  background: rgba(255, 255, 255, 0.6);
}

.btn--disabled {
  opacity: 0.55;
  cursor: not-allowed;
  filter: grayscale(0.2);
}

.toast {
  border-radius: 14px;
  padding: 12px 14px;
  margin: 0 0 14px;
  border: 1px solid var(--border);
}

.toast-stack {
  position: fixed;
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%);
  z-index: 50;
  display: grid;
  gap: 10px;
  pointer-events: none;
  width: min(92vw, 520px);
}

.toast--floating {
  margin: 0;
  box-shadow: var(--shadow);
  pointer-events: none;
}

.toast--hide {
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 200ms ease, transform 200ms ease;
}

.toast--error {
  background: rgba(220, 38, 38, 0.08);
  border-color: rgba(220, 38, 38, 0.22);
}

.toast--info {
  background: rgba(37, 99, 235, 0.08);
  border-color: rgba(37, 99, 235, 0.2);
}

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

.quiz__meta {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.quiz__title {
  font-size: 18px;
  font-weight: 700;
}

.quiz__stats {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.pill {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--border);
  font-size: 12px;
  color: var(--muted);
}

.pill--ok {
  color: var(--ok);
  border-color: rgba(22, 163, 74, 0.22);
}

.pill--bad {
  color: var(--bad);
  border-color: rgba(220, 38, 38, 0.22);
}

.progressbar {
  height: 8px;
  background: rgba(17, 24, 39, 0.06);
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.progressbar__fill {
  height: 100%;
  background: linear-gradient(90deg, rgba(37, 99, 235, 0.95), rgba(22, 163, 74, 0.85));
  width: 0%;
}

.quiz__card {
  min-height: 260px;
  touch-action: pan-y;
}

.quiz__qtype {
  font-size: 12px;
  color: var(--muted);
  margin-bottom: 10px;
}

.quiz__qtitle {
  font-size: 16px;
  line-height: 1.6;
  margin-bottom: 14px;
}

.quiz__options {
  display: grid;
  gap: 10px;
}

.option {
  width: 100%;
  text-align: left;
  padding: 12px 12px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.92);
  color: var(--text);
  cursor: pointer;
  font-weight: 600;
  line-height: 1.5;
}

.option[disabled] {
  cursor: not-allowed;
  opacity: 0.75;
}

.option--selected {
  border-color: rgba(37, 99, 235, 0.55);
}

.option--correct {
  border-color: rgba(22, 163, 74, 0.55);
  background: rgba(22, 163, 74, 0.08);
}

.option--wrong {
  border-color: rgba(220, 38, 38, 0.55);
  background: rgba(220, 38, 38, 0.08);
}

.quiz__result {
  margin-top: 14px;
  font-weight: 700;
}

.quiz__analysis {
  margin-top: 10px;
  color: var(--muted);
  line-height: 1.65;
}

.analysis__label {
  font-weight: 700;
  color: var(--text);
}

.quiz__nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

@media (max-width: 560px) {
  .quiz__nav {
    grid-template-columns: 1fr 1fr;
  }
}

.quiz__finish {
  display: grid;
}

.quiz__summary {
  line-height: 1.8;
}