:root {
  --bg: #f6f7f4;
  --ink: #17211c;
  --muted: #66736d;
  --line: #d8ddd7;
  --panel: #ffffff;
  --accent: #0d5c63;
  --accent-strong: #083f44;
  --correct: #dff3e4;
  --correct-border: #2e8a4f;
  --wrong: #ffe1df;
  --wrong-border: #bd352c;
  --expected: #fff1b8;
  --expected-border: #b98500;
  --shadow: 0 12px 32px rgba(23, 33, 28, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.45;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(16px, 4vw, 44px);
  background: rgba(246, 247, 244, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}

.auth-box {
  display: grid;
  gap: 8px;
  min-width: 420px;
}

.auth-box span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

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

.login-form input {
  min-width: 0;
  width: 150px;
  height: 42px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  font: inherit;
}

#registerButton,
#recoverButton {
  background: #ffffff;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: 30px;
  font-weight: 800;
}

p {
  margin: 4px 0 0;
  color: var(--muted);
}

.status-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(92px, 1fr));
  gap: 10px;
  min-width: 580px;
}

.status-grid > div {
  padding: 10px 12px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.status-grid span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  text-transform: uppercase;
}

.status-grid strong {
  display: block;
  margin-top: 3px;
  font-size: 21px;
}

.traffic-light {
  position: relative;
  padding-left: 24px;
}

.traffic-light::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid rgba(23, 33, 28, 0.18);
  transform: translateY(-50%);
}

.traffic-green::before {
  background: #31a354;
}

.traffic-yellow::before {
  background: #f1bc2b;
}

.traffic-red::before {
  background: #d63b32;
}

.traffic-neutral::before {
  background: #c8cfcb;
}

main {
  width: min(1120px, calc(100% - 32px));
  margin: 22px auto 44px;
}

.access-panel {
  width: min(720px, calc(100% - 32px));
  margin: 28px auto;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 6px solid var(--accent);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.access-panel h2 {
  margin: 0 0 6px;
  font-size: 24px;
}

.password-page {
  display: grid;
  place-items: center;
  min-height: 100vh;
  margin: 0;
  padding: 24px;
}

.password-card {
  width: min(460px, 100%);
  padding: 24px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 6px solid var(--accent);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.password-card h1 {
  margin-bottom: 8px;
}

.password-form {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.password-form label {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.password-form input {
  width: 100%;
  height: 46px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  font: inherit;
}

.password-link {
  display: inline-block;
  margin-top: 16px;
  color: var(--accent);
  font-weight: 700;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px;
  margin-bottom: 18px;
}

button {
  min-height: 42px;
  padding: 0 16px;
  border: 1px solid var(--accent);
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

button:hover {
  background: var(--accent-strong);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.56;
}

#newSessionButton {
  background: #ffffff;
  color: var(--accent);
}

#resetButton {
  background: #ffffff;
  color: var(--wrong-border);
  border-color: var(--wrong-border);
}

.share-panel {
  display: grid;
  gap: 12px;
  margin-bottom: 18px;
  padding: 16px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 6px solid var(--accent);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.topics-panel {
  display: grid;
  gap: 14px;
  margin-bottom: 18px;
  padding: 16px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.topics-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}

.topics-head h2 {
  margin: 0;
  font-size: 20px;
}

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

.topics-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 8px;
}

.topic-option {
  display: grid;
  grid-template-columns: 22px 1fr;
  gap: 8px;
  align-items: start;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfb;
}

.topic-option input {
  width: 18px;
  height: 18px;
  margin: 2px 0 0;
  accent-color: var(--accent);
}

.topic-option span {
  display: block;
  color: var(--muted);
  font-size: 12px;
}

.share-panel code {
  display: block;
  overflow-wrap: anywhere;
  padding: 10px 12px;
  background: #eef3ef;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.share-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.summary {
  margin-bottom: 18px;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 6px solid var(--accent);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.summary.promosso {
  border-left-color: var(--correct-border);
}

.summary.bocciato {
  border-left-color: var(--wrong-border);
}

.summary h2 {
  margin: 0 0 6px;
  font-size: 24px;
}

.quiz-list {
  display: grid;
  gap: 14px;
}

.question {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.question-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 18px 10px;
}

.question-title {
  margin: 0;
  font-size: 18px;
}

.question-number {
  flex: 0 0 auto;
  color: var(--muted);
  font-weight: 700;
}

.question img {
  display: block;
  max-width: min(420px, calc(100% - 36px));
  margin: 0 18px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.options {
  display: grid;
  gap: 8px;
  padding: 0 18px 18px;
}

.option {
  display: grid;
  grid-template-columns: 26px 1fr;
  gap: 10px;
  align-items: start;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfb;
  cursor: pointer;
}

.option input {
  width: 18px;
  height: 18px;
  margin: 2px 0 0;
  accent-color: var(--accent);
}

.option strong {
  margin-right: 6px;
}

.option.correct {
  background: var(--correct);
  border-color: var(--correct-border);
}

.option.wrong {
  background: var(--wrong);
  border-color: var(--wrong-border);
}

.option.expected {
  background: var(--expected);
  border-color: var(--expected-border);
}

.explanation-box {
  margin: 0 18px 18px;
  padding: 14px;
  background: #eef6f7;
  border: 1px solid #b9d6da;
  border-left: 5px solid var(--accent);
  border-radius: 8px;
}

.explanation-box h3 {
  margin: 0 0 6px;
  font-size: 17px;
}

.explanation-box p {
  margin-top: 8px;
}

.explanation-ref {
  font-size: 13px;
  font-weight: 700;
}

.hidden {
  display: none;
}

@media (max-width: 760px) {
  .topbar {
    position: static;
    display: block;
  }

  .auth-box {
    margin-top: 14px;
    min-width: 0;
  }

  .login-form {
    display: grid;
  }

  .login-form input {
    width: 100%;
  }

  .status-grid {
    grid-template-columns: repeat(2, 1fr);
    min-width: 0;
    margin-top: 14px;
  }

  .status-grid strong {
    font-size: 18px;
  }

  .toolbar {
    position: sticky;
    top: 0;
    z-index: 4;
    justify-content: stretch;
    padding: 10px 0;
    background: var(--bg);
  }

  .toolbar button {
    flex: 1;
  }

  .topics-head {
    display: grid;
  }

  .question-header {
    display: block;
  }

  .question-number {
    display: block;
    margin-top: 8px;
  }
}