:root {
  --accent: #2f8f6e;
  --accent2: #22c1c3;
  --grad: linear-gradient(120deg, var(--accent), var(--accent2));
  --btn-c1: var(--accent);
  --btn-c2: var(--accent2);
  --btn-grad: linear-gradient(120deg, var(--btn-c1), var(--btn-c2));
  --bg: #f4f1ea;
  --text: #2b2b2b;
  --card-bg: #ffffff;
  --card-border: #e6e2d8;
  --muted: #6b6b66;
  --danger: #c0392b;
  --hero-grid: rgba(20, 20, 40, 0.05);
}

:root[data-theme="dark"] {
  --accent: #4fd1a5;
  --accent2: #5eead4;
  /* ボタンの塗りは文字用のaccentよりトーンを落として、暗い背景で発光しすぎないようにする */
  --btn-c1: #2f8f6e;
  --btn-c2: #1c9a9c;
  --bg: #121214;
  --text: #ececee;
  --card-bg: #1c1c20;
  --card-border: #2c2c31;
  --muted: #9a9aa2;
  --danger: #ff7a70;
  --hero-grid: rgba(255, 255, 255, 0.06);
}
:root[data-theme="dark"] .ad-slot {
  background: repeating-linear-gradient(45deg, #1c1c20, #1c1c20 10px, #232328 10px, #232328 20px);
  color: #9a9aa2;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Hiragino Sans", "Yu Gothic", "Meiryo", sans-serif;
  background-color: var(--bg);
  background-image:
    radial-gradient(circle, var(--hero-grid) 1px, transparent 1px),
    radial-gradient(900px circle at 15% -10%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 55%),
    radial-gradient(800px circle at 100% 10%, color-mix(in srgb, var(--accent2) 9%, transparent), transparent 55%);
  background-size: 22px 22px, auto, auto;
  background-attachment: fixed;
  color: var(--text);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  align-items: center;
}

.site-header {
  text-align: center;
  padding: 1.6rem 1rem 0.6rem;
}

.site-header h1 {
  margin: 0;
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.subtitle {
  margin: 0.3rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.ad-slot {
  width: 100%;
  max-width: 640px;
  min-height: 60px;
  margin: 0.8rem auto;
  display: flex;
  align-items: center;
  justify-content: center;
  background: repeating-linear-gradient(45deg, #eee, #eee 10px, #e2e2e2 10px, #e2e2e2 20px);
  color: #999;
  font-size: 0.8rem;
  border-radius: 6px;
}

main {
  width: 100%;
  max-width: 520px;
  padding: 0 1rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.site-nav {
  width: 100%;
  padding: 0.6rem 1rem;
  font-size: 0.85rem;
  box-sizing: border-box;
}
.site-nav a {
  display: inline-flex;
  align-items: center;
  color: var(--text);
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 999px;
  padding: 0.35rem 0.9rem;
  text-decoration: none;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.site-nav a:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.hidden {
  display: none !important;
}

.setup-screen,
.lobby-panel,
.howto {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  padding: 1.5rem 1.2rem;
  margin-bottom: 1rem;
  text-align: center;
}

.setup-screen h2,
.lobby-panel h3,
.howto h2 {
  margin-top: 0;
  font-size: 1.15rem;
  padding-left: 0.6rem;
  border-left: 4px solid transparent;
  border-image: var(--grad) 1;
}

.name-input {
  display: block;
  width: 100%;
  max-width: 260px;
  margin: 0.5rem auto 1.2rem;
  padding: 0.6rem 0.7rem;
  border: 1px solid var(--card-border);
  border-radius: 6px;
  background: var(--card-bg);
  color: var(--text);
  font-size: 1rem;
  text-align: center;
}

.mode-btn {
  padding: 0.8rem 1rem;
  border: none;
  border-radius: 8px;
  background: var(--btn-grad);
  color: #fff;
  font-size: 1rem;
  font-weight: bold;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.mode-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px color-mix(in srgb, var(--btn-c1) 35%, transparent);
}

.mode-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.reset-btn {
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 6px;
  background: var(--btn-grad);
  color: #fff;
  font-size: 0.9rem;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.reset-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px color-mix(in srgb, var(--btn-c1) 35%, transparent);
}

.secondary-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1rem;
  border: 1px solid var(--accent);
  border-radius: 6px;
  background: transparent;
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: bold;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.15s ease, transform 0.15s ease;
}

.secondary-btn:hover {
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  transform: translateY(-1px);
}

.link-btn {
  border: none;
  background: none;
  color: var(--accent);
  font-size: 0.85rem;
  cursor: pointer;
  text-decoration: underline;
  padding: 0.3rem;
}

.online-choice {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
}

.join-row {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

.join-row input {
  padding: 0.6rem 0.7rem;
  border: 1px solid var(--card-border);
  border-radius: 6px;
  background: var(--card-bg);
  color: var(--text);
  font-size: 1rem;
  width: 130px;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 0.15em;
}

.host-wait {
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--card-border);
}

.room-code {
  font-size: 2rem;
  font-weight: bold;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin: 0.5rem 0;
}

.online-status {
  color: var(--muted);
  font-size: 0.9rem;
  margin: 0.5rem 0 0;
}

.online-error {
  color: var(--danger);
  font-size: 0.9rem;
  margin-top: 0.8rem;
}

.roster {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.roster-item {
  background: color-mix(in srgb, var(--accent) 8%, var(--card-bg));
  border-radius: 6px;
  padding: 0.5rem 0.8rem;
  font-weight: bold;
}

.game-area {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.theme-box,
.my-number-box {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  padding: 1rem 1.2rem;
  margin-bottom: 0.8rem;
  text-align: center;
}

.theme-label,
.my-number-label {
  margin: 0;
  font-size: 0.8rem;
  color: var(--muted);
}

.theme-title {
  margin: 0.3rem 0 0.2rem;
  font-size: 1.2rem;
  font-weight: bold;
}

.theme-scale {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

#reroll-theme-btn {
  display: inline-block;
  margin-top: 0.6rem;
}

.my-number {
  margin: 0.3rem 0 0;
  font-size: 3rem;
  font-weight: bold;
  color: var(--accent);
}

.game-hint {
  width: 100%;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
  margin: 0 0 1rem;
}

.order-panel {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  padding: 1rem 1.2rem;
  margin-bottom: 1rem;
  text-align: center;
}

.order-panel h3 {
  margin-top: 0;
  font-size: 1rem;
}

.order-candidates {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1rem;
}

.order-candidate-btn {
  padding: 0.5rem 0.8rem;
  font-size: 0.9rem;
}

.order-built {
  text-align: left;
  max-width: 260px;
  margin: 0 auto 1rem;
  padding-left: 1.4rem;
}

.order-actions {
  display: flex;
  gap: 0.8rem;
  justify-content: center;
  align-items: center;
}

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.overlay.hidden {
  display: none;
}

.overlay-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 1.5rem 2rem;
  text-align: center;
  max-width: 90%;
  width: 360px;
  position: relative;
  z-index: 1001;
}

.result-text {
  font-size: 1.5rem;
  font-weight: 800;
  line-height: 1.4;
  margin: 0 0 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--card-border);
}

.result-order-label {
  margin: 0 0 0.5rem;
  font-size: 0.85rem;
  color: var(--muted);
}

.result-order {
  text-align: left;
  max-width: 260px;
  margin: 0 auto 1rem;
  padding-left: 1.4rem;
}

.result-order li {
  padding: 0.35rem 0;
  line-height: 1.5;
}

.result-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  justify-content: center;
  align-items: center;
  margin-top: 0.4rem;
  padding-top: 1rem;
  border-top: 1px solid var(--card-border);
}

.other-games {
  margin-top: 1.2rem;
  border-top: 1px solid var(--card-border);
  padding-top: 1rem;
}

.other-games p {
  margin: 0 0 0.5rem;
  font-weight: bold;
  color: var(--muted);
}

.other-games ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
}

.other-games a {
  display: inline-block;
  padding: 0.4rem 0.8rem;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 999px;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.85rem;
  transition: border-color 0.15s ease, transform 0.15s ease;
}

.other-games a:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.howto ul {
  padding-left: 1.2rem;
  line-height: 1.6;
  text-align: left;
}

.site-footer {
  margin-top: auto;
  padding: 1rem;
  color: var(--muted);
  font-size: 0.8rem;
}

@media (max-width: 480px) {
  .site-header h1 {
    font-size: 1.4rem;
  }
  .overlay-card {
    padding: 1.2rem 1rem;
  }
  .my-number {
    font-size: 2.4rem;
  }
}