:root {
  --bg: #f6f9fc;
  --panel: #ffffff;
  --ink: #14213d;
  --accent: #0f6bff;
  --accent-2: #09a180;
  --muted: #5c6b80;
  --danger: #c83f49;
  --line: #d9e2ee;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  background: radial-gradient(circle at top right, #dfeeff, var(--bg));
  color: var(--ink);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px;
}

h1 {
  margin: 4px 0 16px;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 14px;
  box-shadow: 0 8px 24px rgba(20, 33, 61, 0.06);
}

label {
  display: block;
  margin-bottom: 10px;
}

input,
select,
button,
textarea {
  font: inherit;
}

input,
select,
textarea {
  width: 100%;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid var(--line);
}

button {
  border: none;
  border-radius: 10px;
  padding: 10px 14px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  font-weight: 700;
}

button.secondary {
  background: #6b7280;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.row {
  display: flex;
  gap: 10px;
  margin-bottom: 10px;
}

.join-row input {
  text-transform: uppercase;
}

.message {
  min-height: 18px;
  color: var(--danger);
  margin: 0;
}

.players {
  display: grid;
  gap: 8px;
  margin: 10px 0;
}

.player {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.player.turn {
  border-color: var(--accent-2);
  background: #ecfff8;
}

.board {
  --size: 6;
  display: grid;
  grid-template-columns: repeat(var(--size), minmax(0, 1fr));
  gap: 8px;
  margin: 12px 0;
  width: 100%;
  max-width: 100%;
  overflow: hidden;
}

.card {
  aspect-ratio: 1;
  min-width: 0;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #dbe7ff;
  display: grid;
  place-items: center;
  font-size: clamp(1rem, 3vw, 2rem);
  font-weight: 700;
  padding: 0;
}

.card.clickable {
  cursor: pointer;
  background: #b8d0ff;
}

.card.revealed {
  background: #fff;
}

.card.matched {
  background: #d9ffe6;
}

.board[data-size="4"] {
  gap: 10px;
}

.board[data-size="6"] {
  gap: 7px;
}

.board[data-size="8"] {
  gap: 4px;
}

.board[data-size="6"] .card {
  font-size: clamp(0.95rem, 2.4vw, 1.45rem);
}

.board[data-size="8"] .card {
  font-size: clamp(0.8rem, 1.8vw, 1.15rem);
}

.banner {
  background: #fff3cd;
  color: #664d03;
  border: 1px solid #ffecb5;
  padding: 12px;
  border-radius: 10px;
  margin-bottom: 12px;
}

.win-log {
  list-style: none;
  margin: 0;
  padding: 0;
}

.win-log li {
  border-bottom: 1px dashed var(--line);
  padding: 8px 0;
}

.footer {
  border-top: 1px solid var(--line);
  background: #fff;
  padding: 12px 20px;
  text-align: center;
}

.modal {
  position: fixed;
  inset: 0;
  background: rgba(20, 33, 61, 0.45);
  display: grid;
  place-items: center;
  z-index: 999;
  padding: 16px;
}

.modal-card {
  width: min(92vw, 360px);
  background: #fff;
  border-radius: 14px;
  border: 1px solid var(--line);
  padding: 16px;
  text-align: center;
  box-shadow: 0 12px 30px rgba(20, 33, 61, 0.2);
}

.modal-card h3 {
  margin: 0 0 8px;
}

.modal-card p {
  margin: 0 0 12px;
  font-size: 1.1rem;
}

.hidden {
  display: none !important;
}

@media (max-width: 700px) {
  .container {
    padding: 12px;
  }

  .panel {
    padding: 10px;
  }

  .row {
    flex-direction: column;
  }

  .board[data-size="4"] {
    gap: 7px;
  }

  .board[data-size="6"] {
    gap: 5px;
  }

  .board[data-size="8"] {
    gap: 3px;
  }
}