:root {
  color-scheme: dark;
  --bg: #08101e;
  --bg-raised: #0e192a;
  --panel: rgba(16, 29, 48, 0.9);
  --panel-strong: #13243a;
  --line: rgba(159, 184, 214, 0.18);
  --line-strong: rgba(159, 184, 214, 0.32);
  --text: #f1f7ff;
  --muted: #93a7bf;
  --cyan: #39d5dc;
  --cyan-soft: rgba(57, 213, 220, 0.13);
  --amber: #ffbd59;
  --amber-soft: rgba(255, 189, 89, 0.13);
  --red: #ff7d7d;
  --green: #69dfa8;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.3);
  --radius: 18px;
  font-family: Inter, "Hiragino Sans", "Yu Gothic UI", "Yu Gothic", Meiryo, sans-serif;
}

* { box-sizing: border-box; }

html { min-width: 320px; background: var(--bg); }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 8% 0%, rgba(57, 213, 220, 0.1), transparent 29rem),
    radial-gradient(circle at 92% 16%, rgba(255, 189, 89, 0.07), transparent 25rem),
    linear-gradient(180deg, #07101d 0%, #091321 45%, #07101c 100%);
}

button, input { font: inherit; }
button { color: inherit; }

.app-shell { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }

.topbar {
  min-height: 104px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
}

.brand, .top-actions, .section-heading, .tool-heading-row,
.response-title-row, .subheading-row, .result-actions {
  display: flex;
  align-items: center;
}

.brand { gap: 15px; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 1px solid rgba(57, 213, 220, 0.45);
  color: var(--cyan);
  font: 700 0.82rem/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: 0.1em;
  box-shadow: inset 0 0 22px rgba(57, 213, 220, 0.08);
}

.eyebrow, .section-index {
  margin: 0 0 5px;
  color: var(--cyan);
  font: 700 0.72rem/1.2 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: 0.17em;
}

h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 0; font-size: clamp(1.3rem, 2vw, 1.65rem); letter-spacing: 0.035em; }
h2 { margin-bottom: 0; font-size: 1.15rem; letter-spacing: 0.025em; }
h3 { margin: 0; font-size: 0.92rem; }

.top-actions { gap: 12px; }
.level-badge {
  padding: 8px 11px;
  border: 1px solid rgba(57, 213, 220, 0.28);
  color: var(--cyan);
  background: var(--cyan-soft);
  border-radius: 999px;
  font: 700 0.75rem/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: 0.08em;
}

main { padding: 28px 0 22px; }

.status-strip {
  display: grid;
  grid-template-columns: auto minmax(120px, 1fr) auto;
  align-items: center;
  gap: 20px;
  margin-bottom: 20px;
}

.turn-status { display: flex; align-items: baseline; gap: 10px; }
.status-label { color: var(--muted); font: 700 0.7rem ui-monospace, monospace; letter-spacing: 0.16em; }
.turn-status strong { font: 700 1.15rem ui-monospace, monospace; }
.status-denominator { color: var(--muted); font-weight: 500; }
.progress-track { height: 3px; overflow: hidden; background: rgba(159, 184, 214, 0.12); }
.progress-track span { display: block; width: 0; height: 100%; background: var(--cyan); transition: width 240ms ease; }
.game-status { margin: 0; color: var(--muted); font-size: 0.9rem; text-align: right; }

.workspace-grid { display: grid; grid-template-columns: minmax(0, 1.55fr) minmax(300px, 0.8fr); gap: 20px; }
.panel {
  border: 1px solid var(--line);
  background: linear-gradient(150deg, rgba(19, 36, 58, 0.92), rgba(11, 22, 38, 0.95));
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.play-card, .tool-card, .history-card { padding: 24px; }
.section-heading { justify-content: space-between; gap: 16px; margin-bottom: 22px; }
.text-button {
  min-height: 42px;
  padding: 0 4px;
  border: 0;
  background: none;
  color: var(--muted);
  cursor: pointer;
  text-decoration: underline;
  text-decoration-color: transparent;
  text-underline-offset: 4px;
}
.text-button:hover { color: var(--text); text-decoration-color: var(--line-strong); }

.guess-input {
  width: 100%;
  height: 88px;
  border: 1px solid var(--line-strong);
  border-radius: 14px;
  outline: none;
  background: rgba(4, 12, 23, 0.52);
  color: var(--text);
  text-align: center;
  font: 700 clamp(2rem, 7vw, 3.35rem)/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: 0.42em;
  text-indent: 0.42em;
  caret-color: var(--cyan);
  transition: border-color 160ms ease, box-shadow 160ms ease;
}
.guess-input::placeholder { color: rgba(147, 167, 191, 0.27); }
.guess-input:focus { border-color: var(--cyan); box-shadow: 0 0 0 4px rgba(57, 213, 220, 0.1); }
.guess-input:disabled { opacity: 0.55; cursor: not-allowed; }
.input-message { min-height: 21px; margin: 9px 0 14px; color: var(--muted); font-size: 0.83rem; }
.input-message.is-valid { color: var(--green); }
.input-message.is-warning { color: var(--amber); }
.input-message.is-error { color: var(--red); }

.keypad { display: none; grid-template-columns: repeat(3, 1fr); gap: 8px; margin-bottom: 12px; }
.keypad button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(6, 15, 27, 0.56);
  cursor: pointer;
}
.keypad button:active { background: var(--cyan-soft); border-color: rgba(57, 213, 220, 0.45); }

.button {
  min-height: 46px;
  border-radius: 11px;
  padding: 0 18px;
  border: 1px solid transparent;
  font-weight: 700;
  cursor: pointer;
  transition: transform 120ms ease, background-color 150ms ease, border-color 150ms ease;
}
.button:not(:disabled):active { transform: translateY(1px); }
.button:disabled { cursor: not-allowed; opacity: 0.38; }
.button-primary { width: 100%; background: var(--cyan); color: #041119; }
.button-primary:hover:not(:disabled) { background: #64e7e9; }
.button-secondary { background: var(--amber-soft); color: var(--amber); border-color: rgba(255, 189, 89, 0.32); }
.button-quiet { background: rgba(159, 184, 214, 0.07); color: var(--text); border-color: var(--line); }
.button-quiet:hover { border-color: var(--line-strong); background: rgba(159, 184, 214, 0.11); }

.response-area { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--line); }
.response-title-row { justify-content: space-between; }
.last-guess { color: var(--muted); font: 600 0.86rem ui-monospace, monospace; letter-spacing: 0.12em; }
.score-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 11px; }
.score-card { position: relative; min-height: 126px; padding: 18px; overflow: hidden; border-radius: 13px; }
.score-exact { border: 1px solid rgba(57, 213, 220, 0.27); background: var(--cyan-soft); }
.score-hit { border: 1px solid rgba(255, 189, 89, 0.27); background: var(--amber-soft); }
.score-symbol { position: absolute; top: 13px; right: 16px; color: rgba(241, 247, 255, 0.15); font: 700 2rem ui-monospace, monospace; }
.score-card strong { display: block; font: 700 3.4rem/1 ui-monospace, monospace; }
.score-exact strong { color: var(--cyan); }
.score-hit strong { color: var(--amber); }
.score-card p { margin: 9px 0 0; color: var(--muted); font-size: 0.82rem; }

.tool-heading-row { align-items: flex-start; }
.switch-control { display: flex; align-items: center; gap: 9px; cursor: pointer; color: var(--muted); font: 700 0.77rem ui-monospace, monospace; }
.switch-control input { position: absolute; opacity: 0; pointer-events: none; }
.switch-track { width: 42px; height: 24px; padding: 3px; border: 1px solid var(--line-strong); border-radius: 999px; background: rgba(4, 12, 23, 0.6); transition: 160ms ease; }
.switch-track span { display: block; width: 16px; height: 16px; border-radius: 50%; background: var(--muted); transition: 160ms ease; }
.switch-control input:checked + .switch-track { border-color: var(--cyan); background: var(--cyan-soft); }
.switch-control input:checked + .switch-track span { transform: translateX(18px); background: var(--cyan); }
.switch-control input:focus-visible + .switch-track { outline: 3px solid rgba(57, 213, 220, 0.24); outline-offset: 2px; }
.switch-control input:disabled + .switch-track { opacity: 0.5; }
.tool-mode-note { margin: -8px 0 22px; color: var(--muted); font-size: 0.84rem; line-height: 1.65; }
.candidate-count-block { padding: 18px; border: 1px solid var(--line); background: rgba(4, 12, 23, 0.38); border-radius: 13px; }
.candidate-count-block span { display: block; color: var(--muted); font-size: 0.8rem; }
.candidate-count-block strong { margin-right: 6px; color: var(--text); font: 700 2.15rem/1.35 ui-monospace, monospace; }
.candidate-count-block small { color: var(--muted); }
.consistency-check { display: grid; grid-template-columns: 10px 1fr; gap: 12px; margin: 14px 0 22px; padding: 15px; border: 1px solid var(--line); border-radius: 12px; }
.check-indicator { width: 9px; height: 9px; margin-top: 5px; border-radius: 50%; background: var(--muted); }
.consistency-check[data-state="valid"] .check-indicator { background: var(--green); box-shadow: 0 0 12px rgba(105, 223, 168, 0.55); }
.consistency-check[data-state="invalid"] .check-indicator { background: var(--red); box-shadow: 0 0 12px rgba(255, 125, 125, 0.5); }
.consistency-check strong { font-size: 0.9rem; }
.consistency-check p { margin: 4px 0 0; color: var(--muted); font-size: 0.8rem; line-height: 1.5; }
.subheading-row { justify-content: space-between; margin-bottom: 10px; }
.subheading-row span { color: var(--muted); font-size: 0.72rem; }
.candidate-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 7px; }
.candidate-chip { min-height: 38px; border: 1px solid var(--line); border-radius: 8px; background: rgba(4, 12, 23, 0.45); color: var(--text); cursor: pointer; font: 600 0.85rem ui-monospace, monospace; letter-spacing: 0.12em; }
.candidate-chip:hover { color: var(--cyan); border-color: rgba(57, 213, 220, 0.42); }
.rules { margin-top: 24px; border-top: 1px solid var(--line); }
.rules summary { padding: 18px 0 0; color: var(--muted); cursor: pointer; font-weight: 650; }
.rules-body { padding-top: 14px; color: var(--muted); font-size: 0.84rem; line-height: 1.7; }
.rules-body dl { margin: 12px 0; }
.rules-body dl div { display: grid; grid-template-columns: 30px 1fr; gap: 10px; margin: 7px 0; }
.rules-body dt { color: var(--text); font: 700 0.9rem ui-monospace, monospace; }
.rules-body dd { margin: 0; }
.rule-example { margin-bottom: 0; padding: 10px; border-left: 2px solid var(--amber); background: var(--amber-soft); }

.history-card { margin-top: 20px; }
.history-count { color: var(--muted); font: 600 0.8rem ui-monospace, monospace; }
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; min-width: 720px; }
th, td { padding: 13px 12px; border-bottom: 1px solid var(--line); text-align: left; }
th { color: var(--muted); font-size: 0.74rem; font-weight: 650; letter-spacing: 0.05em; }
td { font-size: 0.88rem; }
td.code-cell { font: 700 0.92rem ui-monospace, monospace; letter-spacing: 0.09em; }
.score-cell-t { color: var(--cyan); font-weight: 700; }
.score-cell-h { color: var(--amber); font-weight: 700; }
.consistency-valid { color: var(--green); }
.consistency-invalid { color: var(--red); }
.hidden-value { color: var(--muted); }
.empty-row td { height: 90px; color: var(--muted); text-align: center; }
.history-disclosure { margin: 14px 0 0; color: var(--muted); font-size: 0.78rem; }

.result-panel { margin-top: 24px; padding: 22px; border: 1px solid rgba(57, 213, 220, 0.3); border-radius: 14px; background: linear-gradient(135deg, rgba(57, 213, 220, 0.12), rgba(4, 12, 23, 0.5)); }
.result-panel h2 { margin-bottom: 7px; font-size: 1.5rem; }
.result-panel > p:not(.section-index) { color: var(--muted); line-height: 1.6; }
.secret-display { display: flex; align-items: baseline; justify-content: space-between; gap: 20px; margin: 18px 0; padding: 17px 18px; border: 1px solid var(--line-strong); border-radius: 11px; background: rgba(4, 12, 23, 0.5); }
.secret-display span { color: var(--muted); }
.secret-display strong { color: var(--cyan); font: 700 1.8rem ui-monospace, monospace; letter-spacing: 0.16em; }
.result-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin: 0 0 18px; }
.result-stats div { padding: 11px; border-left: 1px solid var(--line); }
.result-stats dt { color: var(--muted); font-size: 0.72rem; }
.result-stats dd { margin: 5px 0 0; font-weight: 700; }
.result-actions { gap: 10px; }
.result-actions .button { width: auto; flex: 1; }

footer { display: flex; justify-content: space-between; gap: 20px; padding: 18px 0 30px; color: rgba(147, 167, 191, 0.65); font: 500 0.7rem ui-monospace, monospace; letter-spacing: 0.07em; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
[hidden] { display: none !important; }

@media (max-width: 820px) {
  .app-shell { width: min(100% - 24px, 680px); }
  .topbar { min-height: 88px; }
  .workspace-grid { grid-template-columns: 1fr; }
  .status-strip { grid-template-columns: auto 1fr; }
  .game-status { grid-column: 1 / -1; text-align: left; }
  .keypad { display: grid; }
  .tool-card { order: 2; }
  .history-card { order: 3; }
}

@media (max-width: 560px) {
  .app-shell { width: min(100% - 18px, 520px); }
  .topbar { align-items: flex-start; padding: 17px 0; }
  .brand-mark { width: 42px; height: 42px; }
  .eyebrow { display: none; }
  .top-actions { flex-direction: column; align-items: flex-end; gap: 7px; }
  .top-actions .button { min-height: 38px; padding: 0 12px; font-size: 0.8rem; }
  main { padding-top: 20px; }
  .play-card, .tool-card, .history-card { padding: 18px; }
  .guess-input { height: 76px; letter-spacing: 0.32em; text-indent: 0.32em; }
  .score-card { min-height: 112px; padding: 15px; }
  .score-card strong { font-size: 3rem; }
  .result-stats { grid-template-columns: 1fr; }
  .result-stats div { display: flex; justify-content: space-between; border-left: 0; border-bottom: 1px solid var(--line); }
  .result-actions { flex-direction: column; }
  footer { flex-direction: column; gap: 6px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}