:root {
  --bg-top: #03111f;
  --bg-bottom: #0f2740;
  --panel: rgba(7, 25, 44, 0.8);
  --text: #eef7ff;
  --muted: #9ec4e3;
  --line: rgba(148, 216, 255, 0.28);
  --ice: #87d7ff;
  --ice-strong: #2ba4e2;
  --alert: #ff7558;
  --ok: #6ee889;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Barlow", "Trebuchet MS", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 10% 10%, #1b486e 0, transparent 30%),
    radial-gradient(circle at 90% 90%, #1c3f66 0, transparent 35%),
    linear-gradient(155deg, var(--bg-top), var(--bg-bottom));
  display: grid;
  place-items: center;
  padding: 1rem;
  overflow-x: hidden;
}

body::before,
body::after {
  content: "";
  position: fixed;
  width: 26rem;
  height: 26rem;
  border-radius: 50%;
  filter: blur(70px);
  pointer-events: none;
  z-index: -1;
}

body::before {
  background: rgba(57, 165, 230, 0.32);
  top: -9rem;
  right: -8rem;
}

body::after {
  background: rgba(255, 117, 88, 0.24);
  bottom: -10rem;
  left: -8rem;
}

.app-shell {
  width: min(56rem, 94vw);
  display: grid;
  gap: 1rem;
}

.brand {
  padding: 0 0.35rem;
}

.season-tag {
  margin: 0;
  color: var(--ice);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 800;
}

.brand h1 {
  margin: 0.15rem 0;
  font-family: "Bebas Neue", Impact, sans-serif;
  font-size: clamp(2.2rem, 6vw, 4rem);
  letter-spacing: 0.02em;
  line-height: 0.95;
}

.data-stamp {
  margin: 0;
  color: var(--muted);
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 1.1rem;
  padding: clamp(1rem, 3vw, 1.6rem);
  box-shadow: 0 22px 55px rgba(3, 12, 22, 0.38);
  backdrop-filter: blur(5px);
}

.screen {
  display: none;
  opacity: 0;
}

.screen.is-visible {
  display: block;
  animation: panel-in 220ms ease-out forwards;
}

@keyframes panel-in {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

h2 {
  margin-top: 0;
  font-size: clamp(1.35rem, 3.4vw, 2rem);
}

.rules {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
  gap: 0.4rem;
  margin-bottom: 0.7rem;
  color: var(--muted);
}

.btn-primary {
  border: none;
  border-radius: 0.78rem;
  background: linear-gradient(90deg, var(--ice-strong), #46c4ff);
  color: #061522;
  font: inherit;
  font-weight: 800;
  padding: 0.8rem 1.2rem;
  cursor: pointer;
  transition: transform 140ms ease, filter 140ms ease;
}

.btn-primary:hover {
  transform: translateY(-1px);
  filter: brightness(1.05);
}

.btn-primary:disabled {
  opacity: 0.7;
  cursor: not-allowed;
}

.message {
  min-height: 1.3rem;
  color: #ffd6cb;
}

.highscore {
  color: var(--ice);
  font-weight: 600;
}

.hud {
  display: grid;
  grid-template-columns: repeat(4, minmax(5rem, 1fr));
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.hud-item {
  border: 1px solid var(--line);
  border-radius: 0.7rem;
  padding: 0.55rem;
  background: rgba(10, 35, 60, 0.72);
}

.hud-item span {
  display: block;
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-transform: uppercase;
}

.hud-item strong {
  font-size: 1.2rem;
}

.timer-wrap {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 0.9rem;
}

.timer-track {
  height: 0.7rem;
  border-radius: 999px;
  background: rgba(140, 194, 231, 0.2);
  overflow: hidden;
}

.timer-fill {
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, #7ce4ff, #2ca6e4);
  transition: width 250ms linear, background 220ms ease;
}

.timer-fill.is-low {
  background: linear-gradient(90deg, #ffb091, #ff5d43);
}

.question {
  margin-top: 0.1rem;
  margin-bottom: 0.9rem;
}

.answers {
  display: grid;
  gap: 0.65rem;
}

.answer-btn {
  border: 1px solid var(--line);
  background: rgba(13, 44, 74, 0.68);
  color: var(--text);
  font: inherit;
  font-weight: 600;
  text-align: left;
  border-radius: 0.72rem;
  padding: 0.78rem 0.9rem;
  cursor: pointer;
  transition: border-color 140ms ease, transform 120ms ease,
    background 140ms ease;
}

.answer-btn:hover:enabled {
  transform: translateX(2px);
  border-color: rgba(159, 223, 255, 0.7);
}

.answer-btn:disabled {
  cursor: default;
  opacity: 0.95;
}

.answer-btn.correct {
  border-color: rgba(110, 232, 137, 0.9);
  background: rgba(31, 118, 62, 0.42);
}

.answer-btn.wrong {
  border-color: rgba(255, 117, 88, 0.9);
  background: rgba(130, 47, 31, 0.4);
}

.feedback {
  min-height: 1.45rem;
  margin-top: 0.75rem;
  color: var(--muted);
  font-weight: 600;
}

.feedback.good {
  color: var(--ok);
}

.feedback.bad {
  color: var(--alert);
}

.result-details {
  color: var(--muted);
}

@media (max-width: 640px) {
  .hud {
    grid-template-columns: repeat(2, minmax(6rem, 1fr));
  }

  .answer-btn {
    font-size: 0.97rem;
  }
}