:root {
  --bg: #10172d;
  --bg-soft: #18213d;
  --panel: rgba(34, 44, 74, 0.84);
  --panel-strong: rgba(21, 28, 51, 0.94);
  --line: rgba(132, 146, 213, 0.22);
  --text: #eef2ff;
  --muted: #aab6d3;
  --brand: #7d73ff;
  --brand-deep: #6157df;
  --brand-soft: #a58cff;
  --ink: #eef2ff;
  --success: #a58cff;
  --danger: #ff5c85;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.5);
  --radius: 20px;
  --font-display: "Space Grotesk", sans-serif;
  --font-body: "Plus Jakarta Sans", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at top, rgba(125, 115, 255, 0.2), transparent 24%),
    radial-gradient(circle at 85% 12%, rgba(165, 140, 255, 0.14), transparent 16%),
    linear-gradient(180deg, #171e36 0%, #10172d 52%, #0b1022 100%);
  font-family: var(--font-body);
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

button,
input {
  font: inherit;
}

.hidden {
  display: none !important;
}

.flash-stack {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.flash-card {
  padding: 12px 16px;
  border-radius: 14px;
  background: rgba(125, 115, 255, 0.14);
  border: 1px solid rgba(125, 115, 255, 0.28);
  color: var(--text);
}

.site-shell {
  width: min(1200px, calc(100% - 32px));
  margin: 0 auto;
  padding: 24px 0 40px;
}

.site-header,
.hero-panel,
.login-card,
.feature-card,
.content-hero,
.summary-card,
.overview-card,
.game-shell,
.panel-card,
.results-table {
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.site-header {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: center;
  padding: 16px 18px;
  border-radius: 24px;
  background: rgba(22, 30, 54, 0.72);
  position: sticky;
  top: 12px;
  z-index: 5;
}

.brand-mark {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-mark img {
  width: 68px;
  border-radius: 14px;
}

.brand-mark strong,
h1,
h2 {
  font-family: var(--font-display);
}

.brand-mark span {
  display: block;
  color: var(--muted);
  font-size: 0.9rem;
}

.nav-actions,
.hero-actions,
.stats-strip,
.summary-grid,
.game-overview,
.metrics-row,
.admin-grid {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.btn {
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 12px 18px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand) 0%, var(--brand-soft) 100%);
  color: white;
  box-shadow: 0 10px 24px rgba(125, 115, 255, 0.28);
}

.btn-outline {
  border-color: rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
}

.landing-page,
.content-page {
  display: grid;
  gap: 24px;
  margin-top: 24px;
}

.hero-panel {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 28px;
  padding: 36px;
  border-radius: 32px;
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.02)),
    linear-gradient(135deg, rgba(125, 115, 255, 0.14), rgba(125, 115, 255, 0.04));
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #a58cff;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.78rem;
  font-weight: 700;
}

.hero-copy h1,
.content-hero h1 {
  margin: 14px 0 14px;
  font-size: clamp(2.3rem, 5vw, 4.5rem);
  line-height: 0.98;
}

.hero-copy p,
.content-hero p,
.feature-card p,
.overview-card p,
.login-card p {
  color: var(--muted);
  line-height: 1.7;
}

.stats-strip article,
.summary-card,
.metrics-row article {
  min-width: 140px;
  padding: 14px 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.stats-strip strong,
.summary-card strong,
.metrics-row strong,
.hud-item strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.6rem;
}

.stats-strip span,
.summary-card span,
.metrics-row span,
.hud-item span {
  color: var(--muted);
  font-size: 0.88rem;
}

.hero-visual {
  position: relative;
  min-height: 420px;
  border-radius: 28px;
  background:
    radial-gradient(circle at center, rgba(165, 140, 255, 0.18), transparent 34%),
    linear-gradient(135deg, rgba(255, 255, 255, 0.06), rgba(255, 255, 255, 0.02));
  overflow: hidden;
}

.hero-core {
  position: absolute;
  inset: 50% auto auto 50%;
  transform: translate(-50%, -50%);
  width: min(70%, 320px);
  padding: 18px;
  border-radius: 26px;
  background: rgba(255, 255, 255, 0.92);
}

.orbital-card {
  position: absolute;
  padding: 14px 16px;
  border-radius: 18px;
  background: rgba(90, 99, 167, 0.34);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #fffaf5;
  font-weight: 700;
}

.orbital-card span {
  display: block;
  color: rgba(255, 250, 245, 0.72);
  font-size: 0.82rem;
  font-weight: 500;
  margin-top: 3px;
}

.top-left { top: 24px; left: 20px; }
.top-right { top: 54px; right: 20px; }
.bottom-left { bottom: 24px; left: 20px; }
.bottom-right { bottom: 42px; right: 20px; }

.feature-grid,
.summary-grid,
.game-overview {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.feature-card,
.overview-card,
.summary-card,
.panel-card,
.results-table,
.login-card,
.content-hero,
.game-shell {
  background: var(--panel);
  border-radius: 28px;
}

.feature-card h2,
.overview-card h2,
.panel-card h2,
.results-table,
.content-hero h1,
.hero-copy h1 {
  color: var(--text);
}

.overview-card {
  display: grid;
  gap: 16px;
}

.inline-note {
  color: var(--muted);
  font-size: 0.95rem;
}

.feature-card {
  padding: 24px;
}

.feature-card span {
  display: inline-flex;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand), var(--brand-soft));
  color: white;
  font-family: var(--font-display);
}

.login-card,
.content-hero,
.game-shell {
  display: grid;
  gap: 20px;
  padding: 28px;
}

.login-card {
  grid-template-columns: 1fr 360px;
  align-items: center;
}

.login-form {
  display: grid;
  gap: 12px;
}

.hero-login {
  margin: 10px 0 6px;
}

.hero-login label {
  font-weight: 700;
}

.hero-login-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
}

.form-note {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.login-form input,
.grid-cell input,
.stack-form input,
.stack-form select {
  width: 100%;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  padding: 14px 16px;
}

.login-form input::placeholder {
  color: rgba(255, 244, 234, 0.48);
}

.stack-form {
  display: grid;
  gap: 12px;
}

.search-row {
  display: flex;
  gap: 12px;
  align-items: center;
}

.search-row input {
  flex: 1;
  width: 100%;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  padding: 14px 16px;
}

.admin-login-card {
  grid-template-columns: 1fr 380px;
}

.content-hero {
  grid-template-columns: 1fr auto;
  align-items: center;
}

.content-hero.compact {
  grid-template-columns: 1fr auto;
}

.summary-card.spotlight {
  min-width: 220px;
  background: linear-gradient(135deg, rgba(125, 115, 255, 0.22), rgba(255, 255, 255, 0.06));
}

.overview-card,
.panel-card,
.results-table {
  padding: 22px;
}

.game-shell {
  background: var(--panel-strong);
}

.hud {
  display: flex;
  gap: 14px;
}

.hud-item {
  min-width: 140px;
  padding: 16px 18px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
}

.instruction-bar {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  color: var(--muted);
}

td {
  color: rgba(255, 244, 234, 0.88);
}

.number-grid {
  display: grid;
  grid-template-columns: repeat(var(--grid-size), minmax(0, 1fr));
  gap: 4px;
}

.grid-cell {
  aspect-ratio: 1;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(126, 141, 199, 0.16);
  background: rgba(45, 58, 86, 0.9);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.03);
}

.grid-cell.locked {
  background: linear-gradient(180deg, rgba(59, 67, 118, 0.92), rgba(52, 59, 105, 0.92));
  font-size: 1rem;
  font-weight: 800;
  color: #fff4ea;
}

.grid-cell input {
  height: 100%;
  text-align: center;
  padding: 0;
  font-size: 1rem;
  font-weight: 800;
  border: none;
  background: transparent;
  caret-color: transparent;
}

.grid-cell.editable:hover,
.grid-cell.related {
  background: rgba(56, 66, 98, 0.96);
}

.grid-cell.selected {
  background: rgba(72, 83, 122, 0.98);
  box-shadow: 0 0 0 2px rgba(109, 113, 255, 0.42);
}

.grid-cell.subgrid-top {
  border-top-width: 3px;
  border-top-color: #6d71ff;
}

.grid-cell.subgrid-left {
  border-left-width: 3px;
  border-left-color: #6d71ff;
}

.number-grid-shell {
  gap: 16px;
  padding: 20px;
  background:
    linear-gradient(180deg, rgba(18, 24, 49, 0.94), rgba(14, 20, 41, 0.96));
  border-color: rgba(109, 113, 255, 0.18);
}

.number-grid-topbar {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 28px;
}

.board-progress {
  text-align: center;
}

.board-progress strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  color: #a58cff;
}

.board-progress span {
  display: block;
  margin-top: 2px;
  letter-spacing: 0.18em;
  color: #9fabc8;
  font-size: 0.78rem;
}

.board-timer-ring {
  display: grid;
  place-items: center;
  width: 84px;
  height: 84px;
  border-radius: 999px;
  border: 4px solid #6d71ff;
  box-shadow: 0 0 18px rgba(109, 113, 255, 0.2);
}

.board-timer-ring strong {
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: #eef0ff;
}

.number-grid-intro {
  max-width: 820px;
  margin: 0 auto;
  padding: 18px 22px;
  border-radius: 22px;
  background: rgba(39, 50, 75, 0.88);
  border: 1px solid rgba(109, 113, 255, 0.2);
}

.number-grid-intro h2 {
  margin: 0 0 8px;
  font-size: clamp(1.4rem, 2.4vw, 2rem);
  color: #a58cff;
}

.number-grid-intro h2 span {
  font-size: 0.72em;
  font-weight: 500;
  color: #9fabc8;
}

.number-grid-intro p {
  margin: 0;
  color: #aab6d3;
  font-size: clamp(0.92rem, 1.1vw, 1.05rem);
  line-height: 1.55;
}

.number-grid-stage {
  display: grid;
  gap: 16px;
  justify-items: center;
}

.number-grid-board {
  width: min(100%, 560px);
  padding: 8px;
  border-radius: 18px;
  border: 3px solid #6d71ff;
  background: rgba(20, 27, 51, 0.9);
  box-shadow: 0 0 0 3px rgba(109, 113, 255, 0.08);
}

.number-grid-controls {
  width: min(100%, 640px);
  display: grid;
  gap: 14px;
}

.number-grid-status {
  padding: 12px 16px;
  border-radius: 14px;
  text-align: center;
  color: #aab6d3;
  background: rgba(31, 38, 66, 0.92);
  border: 1px solid rgba(109, 113, 255, 0.18);
}

.number-pad {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(52px, 1fr));
  gap: 10px;
}

.pad-key,
.number-grid-actions .btn {
  min-height: 52px;
  border-radius: 14px;
  font-family: var(--font-display);
  font-size: 1.25rem;
}

.pad-key {
  border: 1px solid rgba(109, 113, 255, 0.28);
  background: linear-gradient(180deg, rgba(35, 44, 72, 0.96), rgba(28, 35, 58, 0.96));
  color: #eef0ff;
  cursor: pointer;
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.pad-key:hover {
  transform: translateY(-1px);
  border-color: #6d71ff;
  background: linear-gradient(180deg, rgba(49, 60, 97, 0.98), rgba(34, 43, 69, 0.98));
}

.number-grid-actions {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 12px;
}

.number-grid-actions .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.number-grid-actions #clear-cell {
  border-color: rgba(255, 92, 133, 0.34);
  background: rgba(69, 35, 51, 0.92);
  color: #ff5c85;
}

.tower-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  align-items: end;
  min-height: 360px;
}

.peg {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: center;
  height: 320px;
  border-radius: 22px;
  padding: 18px 12px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.05), rgba(125, 115, 255, 0.11));
  border: 1px solid rgba(255, 255, 255, 0.12);
  position: relative;
  cursor: pointer;
}

.peg.active {
  outline: 2px solid var(--brand-soft);
}

.peg::before {
  content: "";
  position: absolute;
  bottom: 22px;
  width: 12px;
  height: 220px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
}

.peg-label {
  position: absolute;
  top: 14px;
  left: 14px;
  color: #a58cff;
  font-size: 0.85rem;
}

.disk {
  position: relative;
  z-index: 1;
  height: 24px;
  margin-top: 8px;
  border-radius: 999px;
  background: linear-gradient(90deg, #a58cff, var(--brand));
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.result-banner {
  padding: 18px 22px;
  border-radius: 22px;
  background: linear-gradient(135deg, rgba(125, 115, 255, 0.18), rgba(255, 255, 255, 0.06));
  border: 1px solid rgba(255, 255, 255, 0.14);
}

.result-banner.error {
  background: linear-gradient(135deg, rgba(255, 92, 133, 0.2), rgba(255, 255, 255, 0.06));
  border-color: rgba(255, 92, 133, 0.4);
}

.export-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.insight-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.insight-card {
  display: grid;
  gap: 12px;
  padding: 18px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.insight-head {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
}

.insight-head strong {
  color: var(--text);
}

.insight-head span {
  color: #a58cff;
  font-weight: 700;
}

.insight-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.insight-metrics {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.insight-metrics span {
  padding: 8px 10px;
  border-radius: 999px;
  background: rgba(125, 115, 255, 0.12);
  color: #d6dcff;
  font-size: 0.88rem;
}

.settings-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
  margin-bottom: 20px;
}

.setting-card {
  display: grid;
  gap: 8px;
  padding: 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.setting-card strong {
  color: #a58cff;
}

code {
  color: #d6dcff;
  word-break: break-word;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  text-align: left;
  padding: 12px 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

th {
  color: #a58cff;
  font-size: 0.9rem;
  font-weight: 700;
}

@media (max-width: 920px) {
  .hero-panel,
  .login-card,
  .admin-login-card,
  .content-hero,
  .feature-grid,
  .summary-grid,
  .game-overview,
  .admin-grid {
    grid-template-columns: 1fr;
  }

  .settings-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .insight-grid {
    grid-template-columns: 1fr;
  }

  .hero-panel {
    padding: 26px;
  }

  .hero-visual {
    min-height: 340px;
  }

  .number-grid-topbar {
    gap: 22px;
  }

  .number-grid-intro {
    padding: 16px 18px;
  }

  .number-grid-board {
    width: min(100%, 500px);
  }

  .number-grid-controls {
    width: min(100%, 560px);
  }
}

@media (max-width: 640px) {
  .site-shell {
    width: min(100% - 20px, 1200px);
  }

  .site-header,
  .instruction-bar,
  .hero-actions,
  .nav-actions,
  .export-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .search-row {
    flex-direction: column;
    align-items: stretch;
  }

  .settings-grid {
    grid-template-columns: 1fr;
  }

  .number-grid {
    gap: 4px;
  }

  .number-grid-shell {
    padding: 16px;
  }

  .number-grid-topbar {
    justify-content: space-between;
  }

  .board-timer-ring {
    width: 72px;
    height: 72px;
    border-width: 3px;
  }

  .board-timer-ring strong {
    font-size: 1.2rem;
  }

  .number-grid-intro {
    border-radius: 18px;
    padding: 14px;
  }

  .number-grid-board {
    width: 100%;
    padding: 6px;
    border-width: 2px;
    border-radius: 14px;
  }

  .number-grid-actions {
    grid-template-columns: 1fr;
  }

  .pad-key,
  .number-grid-actions .btn {
    min-height: 46px;
    font-size: 1.05rem;
  }

  .hero-login-row {
    grid-template-columns: 1fr;
  }

  .tower-board {
    gap: 10px;
    min-height: 300px;
  }

  .peg {
    height: 260px;
  }
}