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

* {
  margin: 0;
  padding: 0;
  font: inherit;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

html:focus-within {
  scroll-behavior: smooth;
}

html,
body {
  height: 100%;
}

body {
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background: var(--surface, #ffffff);
  color: var(--text, #111827);
  user-select: none;
  -webkit-user-select: none;
  -ms-user-select: none;
}

*::selection {
  background: transparent;
  color: inherit;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
}

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

input,
textarea {
  user-select: text;
  -webkit-user-select: text;
}

:root {
  color-scheme: light dark;
  --surface: #ffffff;
  --surface-muted: #f3f4f6;
  --surface-strong: #111827;
  --border: #d1d5db;
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
  --text: #111827;
  --text-secondary: #4b5563;
  --danger: #dc2626;
  --glass-overlay: rgba(255, 255, 255, 0.78);
  --glass-overlay-muted: rgba(255, 255, 255, 0.64);
  --page-gradient-base: radial-gradient(
      circle at 20% 20%,
      rgba(59, 130, 246, 0.18),
      transparent 55%
    ),
    radial-gradient(circle at 80% 15%, rgba(59, 222, 255, 0.24), transparent 52%),
    linear-gradient(140deg, #eef2ff 0%, #f7faff 50%, #ffffff 100%);
  --page-gradient-overlay: radial-gradient(
      120% 140% at 20% 90%,
      rgba(30, 64, 175, 0.16),
      transparent 70%
    ),
    radial-gradient(90% 120% at 80% 70%, rgba(109, 40, 217, 0.12), transparent 65%);
  --glass-surface: rgba(255, 255, 255, 0.72);
  --glass-surface-fallback: rgba(248, 250, 252, 0.94);
  --glass-border: rgba(148, 163, 184, 0.35);
  --glass-highlight: rgba(255, 255, 255, 0.6);
  --glass-shadow: 0 30px 80px rgba(15, 23, 42, 0.18);
  --glass-blur: 28px;
  --glow-primary: rgba(59, 130, 246, 0.32);
  --glow-secondary: rgba(96, 165, 250, 0.28);
  --glow-accent: color-mix(in srgb, var(--accent) 32%, transparent);
  --glow-ambient: rgba(15, 118, 110, 0.18);
  --glow-strong: rgba(79, 70, 229, 0.24);
  --accent-ring: color-mix(in srgb, var(--accent) 58%, transparent);
  --accent-ring-outer: color-mix(in srgb, var(--accent) 18%, transparent);
  --field-bg: color-mix(in srgb, var(--surface) 90%, rgba(255, 255, 255, 0.02));
  --field-border: color-mix(in srgb, var(--surface-strong) 14%, transparent);
  --field-shadow: rgba(15, 23, 42, 0.14);
  --field-focus-bg: color-mix(in srgb, var(--surface) 96%, transparent);
  --control-bg: color-mix(in srgb, var(--surface) 88%, transparent);
  --control-border: color-mix(in srgb, var(--surface-strong) 12%, transparent);
  --control-shadow: 0 18px 36px rgba(15, 23, 42, 0.16);
  --control-selected-bg: color-mix(in srgb, var(--accent) 18%, var(--surface) 82%);
  --cell-x-color: #2563eb;
  --cell-x-color-strong: #1d4ed8;
  --cell-x-color-soft: #bfdbfe;
  --cell-o-color: #dc2626;
  --cell-o-color-strong: #b91c1c;
  --cell-o-color-soft: #fecaca;
  --cell-glyph-shadow: rgba(15, 23, 42, 0.42);
}

@media (prefers-color-scheme: dark) {
  :root {
    --surface: #111827;
    --surface-muted: #1f2937;
    --surface-strong: #f9fafb;
    --border: #374151;
    --accent: #3b82f6;
    --accent-dark: #2563eb;
    --text: #f9fafb;
    --text-secondary: #d1d5db;
    --glass-overlay: rgba(17, 24, 39, 0.72);
    --glass-overlay-muted: rgba(17, 24, 39, 0.58);
    --page-gradient-base: radial-gradient(
        circle at 18% 22%,
        rgba(37, 99, 235, 0.4),
        transparent 55%
      ),
      radial-gradient(circle at 78% 12%, rgba(14, 116, 144, 0.32), transparent 58%),
      linear-gradient(150deg, #0f172a 0%, #111827 55%, #0b1120 100%);
    --page-gradient-overlay: radial-gradient(
        130% 150% at 16% 88%,
        rgba(56, 189, 248, 0.24),
        transparent 70%
      ),
      radial-gradient(90% 130% at 82% 72%, rgba(99, 102, 241, 0.28), transparent 68%);
    --glass-surface: rgba(15, 23, 42, 0.72);
    --glass-surface-fallback: rgba(17, 24, 39, 0.94);
    --glass-border: rgba(94, 122, 164, 0.4);
    --glass-highlight: rgba(226, 232, 240, 0.2);
    --glass-shadow: 0 30px 90px rgba(8, 15, 35, 0.56);
    --glow-primary: rgba(56, 189, 248, 0.35);
    --glow-secondary: rgba(34, 211, 238, 0.32);
    --glow-accent: rgba(129, 140, 248, 0.32);
    --glow-ambient: rgba(45, 212, 191, 0.22);
    --glow-strong: rgba(30, 64, 175, 0.35);
    --accent-ring: color-mix(in srgb, var(--accent) 56%, transparent);
    --accent-ring-outer: color-mix(in srgb, var(--accent) 22%, transparent);
    --field-bg: color-mix(in srgb, var(--surface) 78%, rgba(148, 163, 184, 0.12));
    --field-border: color-mix(in srgb, var(--surface-strong) 16%, transparent);
    --field-shadow: rgba(2, 6, 23, 0.45);
    --field-focus-bg: color-mix(in srgb, var(--surface) 70%, rgba(148, 163, 184, 0.18));
    --control-bg: color-mix(in srgb, var(--surface) 72%, rgba(148, 163, 184, 0.18));
    --control-border: color-mix(in srgb, var(--surface-strong) 22%, transparent);
    --control-shadow: 0 22px 42px rgba(2, 6, 23, 0.58);
    --control-selected-bg: color-mix(in srgb, var(--accent) 28%, rgba(17, 24, 39, 0.72));
  }
}

:root[data-theme="light"] {
  color-scheme: light;
  --surface: #ffffff;
  --surface-muted: #f3f4f6;
  --surface-strong: #111827;
  --border: #d1d5db;
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
  --text: #111827;
  --text-secondary: #4b5563;
  --glass-overlay: rgba(255, 255, 255, 0.78);
  --glass-overlay-muted: rgba(255, 255, 255, 0.64);
  --page-gradient-base: radial-gradient(
      circle at 20% 20%,
      rgba(59, 130, 246, 0.18),
      transparent 55%
    ),
    radial-gradient(circle at 80% 15%, rgba(59, 222, 255, 0.24), transparent 52%),
    linear-gradient(140deg, #eef2ff 0%, #f7faff 50%, #ffffff 100%);
  --page-gradient-overlay: radial-gradient(
      120% 140% at 20% 90%,
      rgba(30, 64, 175, 0.16),
      transparent 70%
    ),
    radial-gradient(90% 120% at 80% 70%, rgba(109, 40, 217, 0.12), transparent 65%);
  --glass-surface: rgba(255, 255, 255, 0.72);
  --glass-surface-fallback: rgba(248, 250, 252, 0.94);
  --glass-border: rgba(148, 163, 184, 0.35);
  --glass-highlight: rgba(255, 255, 255, 0.6);
  --glass-shadow: 0 30px 80px rgba(15, 23, 42, 0.18);
  --glow-primary: rgba(59, 130, 246, 0.32);
  --glow-secondary: rgba(96, 165, 250, 0.28);
  --glow-ambient: rgba(15, 118, 110, 0.18);
  --glow-strong: rgba(79, 70, 229, 0.24);
  --accent-ring: color-mix(in srgb, var(--accent) 58%, transparent);
  --accent-ring-outer: color-mix(in srgb, var(--accent) 18%, transparent);
  --field-bg: color-mix(in srgb, var(--surface) 90%, rgba(255, 255, 255, 0.02));
  --field-border: color-mix(in srgb, var(--surface-strong) 14%, transparent);
  --field-shadow: rgba(15, 23, 42, 0.14);
  --field-focus-bg: color-mix(in srgb, var(--surface) 96%, transparent);
  --control-bg: color-mix(in srgb, var(--surface) 88%, transparent);
  --control-border: color-mix(in srgb, var(--surface-strong) 12%, transparent);
  --control-shadow: 0 18px 36px rgba(15, 23, 42, 0.16);
  --control-selected-bg: color-mix(in srgb, var(--accent) 18%, var(--surface) 82%);
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --surface: #111827;
  --surface-muted: #1f2937;
  --surface-strong: #f9fafb;
  --border: #374151;
  --accent: #3b82f6;
  --accent-dark: #2563eb;
  --text: #f9fafb;
  --text-secondary: #d1d5db;
  --glass-overlay: rgba(17, 24, 39, 0.72);
  --glass-overlay-muted: rgba(17, 24, 39, 0.58);
  --page-gradient-base: radial-gradient(
      circle at 18% 22%,
      rgba(37, 99, 235, 0.4),
      transparent 55%
    ),
    radial-gradient(circle at 78% 12%, rgba(14, 116, 144, 0.32), transparent 58%),
    linear-gradient(150deg, #0f172a 0%, #111827 55%, #0b1120 100%);
  --page-gradient-overlay: radial-gradient(
      130% 150% at 16% 88%,
      rgba(56, 189, 248, 0.24),
      transparent 70%
    ),
    radial-gradient(90% 130% at 82% 72%, rgba(99, 102, 241, 0.28), transparent 68%);
  --glass-surface: rgba(15, 23, 42, 0.72);
  --glass-surface-fallback: rgba(17, 24, 39, 0.94);
  --glass-border: rgba(94, 122, 164, 0.4);
  --glass-highlight: rgba(226, 232, 240, 0.2);
  --glass-shadow: 0 30px 90px rgba(8, 15, 35, 0.56);
  --glow-primary: rgba(56, 189, 248, 0.35);
  --glow-secondary: rgba(34, 211, 238, 0.32);
  --glow-ambient: rgba(45, 212, 191, 0.22);
  --glow-strong: rgba(30, 64, 175, 0.35);
  --accent-ring: color-mix(in srgb, var(--accent) 56%, transparent);
  --accent-ring-outer: color-mix(in srgb, var(--accent) 22%, transparent);
  --field-bg: color-mix(in srgb, var(--surface) 78%, rgba(148, 163, 184, 0.12));
  --field-border: color-mix(in srgb, var(--surface-strong) 16%, transparent);
  --field-shadow: rgba(2, 6, 23, 0.45);
  --field-focus-bg: color-mix(in srgb, var(--surface) 70%, rgba(148, 163, 184, 0.18));
  --control-bg: color-mix(in srgb, var(--surface) 72%, rgba(148, 163, 184, 0.18));
  --control-border: color-mix(in srgb, var(--surface-strong) 22%, transparent);
  --control-shadow: 0 22px 42px rgba(2, 6, 23, 0.58);
  --control-selected-bg: color-mix(in srgb, var(--accent) 28%, rgba(17, 24, 39, 0.72));
}

:root[data-accent="sky"] {
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
}

:root[data-accent="violet"] {
  --accent: #8b5cf6;
  --accent-dark: #7c3aed;
}

:root[data-accent="emerald"] {
  --accent: #10b981;
  --accent-dark: #059669;
}

:root[data-accent="amber"] {
  --accent: #f59e0b;
  --accent-dark: #d97706;
}

:root[data-accent="rose"] {
  --accent: #f43f5e;
  --accent-dark: #e11d48;
}

:root[data-theme="dark"][data-accent="sky"] {
  --accent: #3b82f6;
  --accent-dark: #2563eb;
}

:root[data-theme="dark"][data-accent="violet"] {
  --accent: #a855f7;
  --accent-dark: #7c3aed;
}

:root[data-theme="dark"][data-accent="emerald"] {
  --accent: #34d399;
  --accent-dark: #10b981;
}

:root[data-theme="dark"][data-accent="amber"] {
  --accent: #fbbf24;
  --accent-dark: #f59e0b;
}

:root[data-theme="dark"][data-accent="rose"] {
  --accent: #fb7185;
  --accent-dark: #f43f5e;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme])[data-accent="sky"] {
    --accent: #3b82f6;
    --accent-dark: #2563eb;
  }

  :root:not([data-theme])[data-accent="violet"] {
    --accent: #a855f7;
    --accent-dark: #7c3aed;
  }

  :root:not([data-theme])[data-accent="emerald"] {
    --accent: #34d399;
    --accent-dark: #10b981;
  }

  :root:not([data-theme])[data-accent="amber"] {
    --accent: #fbbf24;
    --accent-dark: #f59e0b;
  }

  :root:not([data-theme])[data-accent="rose"] {
    --accent: #fb7185;
    --accent-dark: #f43f5e;
    --cell-x-color: #60a5fa;
    --cell-x-color-strong: #3b82f6;
    --cell-x-color-soft: #bfdbfe;
    --cell-o-color: #f87171;
    --cell-o-color-strong: #ef4444;
    --cell-o-color-soft: #fee2e2;
    --cell-glyph-shadow: rgba(2, 6, 23, 0.65);
  }
}

body.page--game {
  background-color: var(--surface-muted);
  background-image: var(--page-gradient-overlay), var(--page-gradient-base);
  background-attachment: fixed;
  background-size: cover;
  color: var(--text);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: clamp(1.5rem, 4vw, 3.5rem) clamp(1.5rem, 5vw, 3.5rem)
    clamp(4.5rem, 10vw, 6.75rem);
  box-sizing: border-box;
  gap: clamp(1.75rem, 4vw, 3rem);
  min-height: 100vh;
  position: relative;
  isolation: isolate;
  overflow-x: hidden;
}

.page-title {
  --badge-size: clamp(3.25rem, 3vw + 2.5rem, 4.25rem);
  position: relative;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(1rem, 2.2vw, 1.75rem);
  align-items: center;
  width: min(64rem, 100%);
  padding: clamp(1.25rem, 2.5vw, 1.9rem) clamp(1.5rem, 3.5vw, 2.75rem);
  padding-block-end: clamp(1.9rem, 3vw, 3rem);
  border-radius: 32px;
  background: color-mix(in srgb, var(--glass-surface) 92%, transparent);
  border: 1px solid color-mix(in srgb, var(--glass-border) 65%, transparent);
  box-shadow: inset 0 1px 0 var(--glass-highlight), var(--glass-shadow);
  overflow: hidden;
  color: var(--text);
}

.page-title::before {
  content: "";
  position: absolute;
  inset: -40% auto auto -12%;
  width: clamp(14rem, 22vw, 18rem);
  height: clamp(14rem, 22vw, 18rem);
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, rgba(59, 130, 246, 0.3), transparent 72%);
  filter: blur(0.5px);
  pointer-events: none;
  z-index: 0;
}

.page-title::after {
  content: "";
  position: absolute;
  inset: auto -10% -45% auto;
  width: clamp(16rem, 26vw, 22rem);
  height: clamp(16rem, 28vw, 24rem);
  border-radius: 50%;
  background: radial-gradient(circle at 60% 60%, rgba(236, 72, 153, 0.25), transparent 68%);
  filter: blur(1px);
  pointer-events: none;
  z-index: 0;
}

.page-title__badge {
  position: relative;
  display: grid;
  place-items: center;
  width: var(--badge-size);
  height: var(--badge-size);
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.95), rgba(14, 165, 233, 0.82));
  box-shadow: 0 18px 40px rgba(59, 130, 246, 0.28), inset 0 1px 0 rgba(255, 255, 255, 0.35);
  z-index: 1;
}

.page-title__badge img {
  width: 62%;
  height: 62%;
  filter: drop-shadow(0 4px 6px rgba(15, 23, 42, 0.15));
}

.page-title__text {
  display: grid;
  gap: clamp(0.2rem, 1vw, 0.6rem);
  z-index: 1;
}

.page-title__eyebrow {
  font-size: clamp(0.8rem, 0.8vw + 0.7rem, 1rem);
  text-transform: uppercase;
  letter-spacing: 0.24em;
  font-weight: 600;
  color: var(--text-secondary);
}

.page-title__headline {
  font-size: clamp(2rem, 4vw + 1rem, 2.95rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--text) 0%, color-mix(in srgb, var(--accent) 68%, var(--text) 32%) 100%);
  -webkit-background-clip: text;
  color: transparent;
}

.page-title__subhead {
  grid-column: 1 / -1;
  font-size: clamp(0.95rem, 0.9vw + 0.8rem, 1.15rem);
  color: var(--text-secondary);
  max-width: 48ch;
  z-index: 1;
}

@media (max-width: 640px) {
  .page-title {
    grid-template-columns: 1fr;
    justify-items: start;
    text-align: left;
  }

  .page-title__badge {
    width: clamp(2.75rem, 12vw, 3.5rem);
    height: clamp(2.75rem, 12vw, 3.5rem);
    border-radius: 20px;
  }

  .page-title__text {
    gap: clamp(0.3rem, 1.4vw, 0.75rem);
  }

  .page-title__subhead {
    max-width: none;
  }
}

body.page--game::before,
body.page--game::after {
  content: "";
  position: fixed;
  inset: auto;
  width: clamp(22rem, 40vw, 34rem);
  height: clamp(22rem, 45vw, 38rem);
  border-radius: 999px;
  filter: blur(60px);
  opacity: 0.7;
  pointer-events: none;
  z-index: -2;
}

body.page--game::before {
  background: radial-gradient(circle, var(--glow-primary), transparent 65%);
  top: clamp(-6rem, -4vw, -2rem);
  left: clamp(-10rem, -6vw, -3rem);
  animation: glow-drift 28s ease-in-out infinite alternate;
}

body.page--game::after {
  background: radial-gradient(circle, var(--glow-ambient), transparent 70%);
  bottom: clamp(-8rem, -6vw, -3rem);
  right: clamp(-12rem, -8vw, -4rem);
  animation: glow-drift 32s ease-in-out infinite alternate-reverse;
}

body.page--error {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #f0f4ff, #ffffff);
  color: #1f2933;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 0 16px;
}

.page--error main {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 16px;
  box-shadow: 0 12px 30px rgba(15, 23, 42, 0.12);
  padding: 48px 56px;
  max-width: 480px;
  text-align: center;
}

.page--error h1 {
  font-size: 2.75rem;
  margin-bottom: 16px;
}

.page--error p {
  font-size: 1.1rem;
  line-height: 1.6;
  margin-bottom: 32px;
}

.page--error .button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 9999px;
  background: #2563eb;
  color: #ffffff;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.35);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.page--error .button:hover {
  background: #1d4ed8;
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(29, 78, 216, 0.4);
}

.page--error .button:focus-visible {
  outline: 3px solid rgba(37, 99, 235, 0.4);
  outline-offset: 4px;
}

@media (max-width: 480px) {
  .page--error main {
    padding: 32px 24px;
  }

  .page--error h1 {
    font-size: 2.1rem;
  }

  .page--error p {
    font-size: 1rem;
  }
}

button {
  font: inherit;
  border-radius: 999px;
  border: 1px solid transparent;
  padding: 10px 18px;
  cursor: pointer;
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: background 180ms ease, border-color 180ms ease,
    color 180ms ease, transform 200ms ease, box-shadow 200ms ease;
}

button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.button {
  --button-bg: var(--glass-overlay);
  --button-bg: color-mix(in srgb, var(--surface) 75%, transparent);
  --button-border: var(--glass-border);
  --button-border: color-mix(in srgb, var(--surface-strong) 16%, transparent);
  --button-shadow-outer: 0 14px 28px rgba(15, 23, 42, 0.18);
  --button-shadow-inner: inset 0 1px 0 rgba(255, 255, 255, 0.35);
  --button-shadow-inner-strong: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2xs);
  padding: clamp(0.55rem, 0.5vw + 0.45rem, 0.75rem)
    clamp(1rem, 1vw + 0.85rem, 1.5rem);
  background: var(--button-bg);
  color: var(--text);
  border-radius: 999px;
  border: 1px solid var(--button-border);
  box-shadow: var(--button-shadow-inner), var(--button-shadow-inner-strong),
    var(--button-shadow-outer);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  font-weight: 600;
}

.button--ghost {
  --button-bg: var(--glass-overlay-muted);
  --button-bg: color-mix(in srgb, var(--surface-muted) 65%, transparent);
  --button-border: var(--glass-border);
  --button-border: color-mix(in srgb, var(--surface-strong) 10%, transparent);
  color: var(--text-secondary);
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4),
    inset 0 0 0 1px rgba(255, 255, 255, 0.14),
    0 18px 38px rgba(15, 23, 42, 0.2);
}

.button:active {
  transform: translateY(0);
  box-shadow: inset 0 2px 6px rgba(15, 23, 42, 0.25),
    inset 0 0 0 1px rgba(255, 255, 255, 0.12),
    0 8px 20px rgba(15, 23, 42, 0.22);
}

.button:focus-visible {
  outline: 3px solid rgba(37, 99, 235, 0.45);
  outline: 3px solid color-mix(in srgb, var(--accent) 60%, transparent);
  outline-offset: 3px;
}

.button__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.25em;
  height: 1.25em;
}

.button__icon img {
  display: block;
  width: 100%;
  height: 100%;
}

.button__label {
  line-height: 1.1;
}

.app-shell {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: clamp(1.25rem, 1.5vw + 1rem, 2.5rem);
  margin-inline: auto;
  width: 100%;
  max-width: clamp(22rem, 85vw, 56rem);
  background: var(--glass-surface-fallback);
  border: 1px solid var(--glass-border);
  border-radius: clamp(1.25rem, 1.5vw + 1rem, 2rem);
  padding: clamp(1.75rem, 2.2vw + 1.5rem, 3.5rem);
  padding-block-end: clamp(3rem, 3vw + 2.25rem, 4.75rem);
  box-shadow: var(--glass-shadow);
  overflow: hidden;
  z-index: 0;
}

.app-shell::before,
.app-shell::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
  mix-blend-mode: screen;
  opacity: 0.8;
  z-index: -1;
}

.app-shell::before {
  width: clamp(10rem, 22vw, 16rem);
  height: clamp(10rem, 22vw, 16rem);
  top: clamp(-5rem, -3vw, -2rem);
  left: clamp(-6rem, -4vw, -2rem);
  background: radial-gradient(circle, var(--glow-secondary), transparent 65%);
}

.app-shell::after {
  width: clamp(8rem, 18vw, 14rem);
  height: clamp(8rem, 18vw, 14rem);
  bottom: clamp(-4rem, -2vw, -1.5rem);
  right: clamp(-5rem, -3vw, -1.5rem);
  background: radial-gradient(circle, var(--glow-accent), transparent 70%);
}

@supports ((backdrop-filter: blur(0.5px)) or (-webkit-backdrop-filter: blur(0.5px))) {
  .app-shell {
    background: linear-gradient(
      135deg,
      var(--glass-highlight) 0%,
      var(--glass-surface) 35%,
      var(--glass-surface) 100%
    );
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
  }
}

@supports not ((backdrop-filter: blur(0.5px)) or (-webkit-backdrop-filter: blur(0.5px))) {
  .app-shell {
    background: var(--glass-surface-fallback);
  }
}

@media (prefers-reduced-motion: reduce) {
  body.page--game {
    background-attachment: scroll;
  }

  body.page--game::before,
  body.page--game::after {
    animation: none;
  }
}

@keyframes glow-drift {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
  }
  50% {
    transform: translate3d(4%, -2%, 0) scale(1.05);
  }
  100% {
    transform: translate3d(-4%, 3%, 0) scale(0.98);
  }
}

.toolbar {
  --toolbar-stack-gap: var(--space-xs);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  flex-wrap: wrap;
  padding: clamp(0.85rem, 0.8vw + 0.65rem, 1.25rem)
    clamp(1.1rem, 1.2vw + 0.8rem, 2rem);
  border-radius: 24px;
  background: var(--glass-overlay);
  background: color-mix(in srgb, var(--surface) 78%, transparent);
  border: 1px solid var(--glass-border);
  border: 1px solid color-mix(in srgb, var(--surface-strong) 14%, transparent);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4),
    inset 0 -1px 0 rgba(255, 255, 255, 0.12),
    0 18px 44px rgba(15, 23, 42, 0.18);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

.toolbar__title {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  font-size: clamp(1.1rem, 2vw + 1rem, 1.85rem);
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.015em;
}

.toolbar__title-label {
  display: inline-block;
}

.toolbar__title-icon {
  width: 1.75em;
  height: 1.75em;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.toolbar__title-icon img {
  width: 100%;
  height: 100%;
}

.toolbar__actions {
  display: flex;
  gap: var(--space-xs);
  flex-wrap: wrap;
  justify-content: flex-end;
}

.toolbar__actions .button {
  min-width: clamp(8rem, 8vw + 4rem, 11rem);
}

@media (max-width: 640px) {
  .toolbar {
    flex-direction: column;
    align-items: stretch;
    gap: var(--toolbar-stack-gap);
  }

  .toolbar__actions {
    width: 100%;
    justify-content: stretch;
    gap: var(--toolbar-stack-gap);
  }

  .toolbar__actions .button {
    width: 100%;
  }
}

.scoreboard {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 2vw, 24px);
  width: 100%;
  padding: clamp(16px, 3vw, 24px);
  flex: none;
  border-radius: 24px;
  background: linear-gradient(
    140deg,
    rgba(59, 130, 246, 0.16),
    rgba(236, 72, 153, 0.12)
  );
  border: 1px solid rgba(255, 255, 255, 0.28);
  box-shadow: 0 24px 48px rgba(15, 23, 42, 0.18);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  isolation: isolate;
  overflow: hidden;
}

.scoreboard::before,
.scoreboard::after {
  content: "";
  position: absolute;
  border-radius: inherit;
  pointer-events: none;
}

.scoreboard::before {
  inset: -35% 12% 58%;
  background: radial-gradient(
    circle at top,
    rgba(255, 255, 255, 0.45),
    transparent 65%
  );
  opacity: 0.55;
}

.scoreboard::after {
  inset: 0;
  border: 1px solid rgba(255, 255, 255, 0.22);
  mix-blend-mode: screen;
  opacity: 0.6;
}

@media (min-width: 560px) {
  .scoreboard {
    grid-template-columns: repeat(2, minmax(220px, 1fr));
    align-content: center;
  }
}

@media (prefers-color-scheme: dark) {
  .scoreboard {
    border-color: rgba(148, 163, 184, 0.32);
    background: linear-gradient(
      145deg,
      rgba(37, 99, 235, 0.22),
      rgba(236, 72, 153, 0.18),
      rgba(17, 24, 39, 0.72)
    );
  }

  .scoreboard::after {
    border-color: rgba(148, 163, 184, 0.24);
  }
}

.scoreboard__player {
  --player-mark-color: var(--accent);
  --player-highlight: color-mix(in srgb, var(--accent) 32%, transparent);
  --player-glow: color-mix(in srgb, var(--accent) 48%, transparent);
  --player-mark-glow: color-mix(in srgb, var(--accent) 42%, transparent);
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(12px, 3vw, 18px);
  padding: clamp(18px, 4vw, 28px) clamp(20px, 5vw, 32px);
  min-height: clamp(72px, 18vw, 110px);
  border-radius: 20px;
  color: var(--surface-strong);
  background: linear-gradient(
    135deg,
    rgba(255, 255, 255, 0.74),
    rgba(148, 163, 184, 0.18)
  );
  border: 1px solid rgba(255, 255, 255, 0.38);
  box-shadow:
    0 18px 36px rgba(15, 23, 42, 0.22),
    0 0 0 1px rgba(255, 255, 255, 0.08),
    0 0 12px var(--player-highlight);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  overflow: hidden;
  isolation: isolate;
  transition:
    transform 220ms ease,
    box-shadow 220ms ease,
    border-color 220ms ease,
    background 220ms ease;
}

.scoreboard__player::before,
.scoreboard__player::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
}

.scoreboard__player::before {
  inset: -42% 10% 56%;
  background: radial-gradient(
    circle at top,
    rgba(255, 255, 255, 0.6),
    transparent 70%
  );
  opacity: 0.55;
  transition: opacity 220ms ease;
}

.scoreboard__player::after {
  inset: -20%;
  z-index: -1;
  background: radial-gradient(
    circle at center,
    var(--player-glow),
    rgba(37, 99, 235, 0)
  );
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 220ms ease, transform 220ms ease;
}

@media (prefers-color-scheme: dark) {
  .scoreboard__player {
    background: linear-gradient(
      135deg,
      rgba(30, 41, 59, 0.82),
      rgba(15, 23, 42, 0.6)
    );
    border-color: rgba(148, 163, 184, 0.34);
    box-shadow:
      0 20px 40px rgba(2, 6, 23, 0.6),
      0 0 0 1px rgba(148, 163, 184, 0.12),
      0 0 12px var(--player-highlight);
  }
}

.scoreboard__player:hover {
  transform: translateY(-2px);
}

.scoreboard__player--active {
  background: linear-gradient(
      135deg,
      rgba(255, 255, 255, 0.88),
      rgba(148, 163, 184, 0.22)
    ),
    linear-gradient(
      135deg,
      rgba(255, 255, 255, 0.12),
      rgba(255, 255, 255, 0)
    );
  border-color: rgba(255, 255, 255, 0.54);
  box-shadow:
    0 24px 52px rgba(15, 23, 42, 0.28),
    0 0 0 2px rgba(255, 255, 255, 0.45),
    0 0 28px var(--player-glow);
  transform: translateY(-4px);
}

.scoreboard__player--active::before {
  opacity: 0.75;
}

.scoreboard__player--active::after {
  opacity: 0.82;
  transform: scale(1);
}

@media (prefers-reduced-motion: no-preference) {
  .scoreboard__player--active::after {
    animation: scoreboard-glow 3s ease-in-out infinite;
  }
}

@media (prefers-reduced-motion: reduce) {
  .scoreboard__player,
  .scoreboard__player::after {
    transition: none;
  }
}

.scoreboard__player--x {
  --player-mark-color: var(--accent);
  --player-highlight: rgba(59, 130, 246, 0.42);
  --player-glow: rgba(59, 130, 246, 0.66);
  --player-mark-glow: rgba(59, 130, 246, 0.58);
}

.scoreboard__player--o {
  --player-mark-color: var(--danger);
  --player-highlight: rgba(244, 63, 94, 0.45);
  --player-glow: rgba(244, 63, 94, 0.62);
  --player-mark-glow: rgba(244, 63, 94, 0.62);
}

.scoreboard__player--draw {
  --player-mark-color: #1f2937;
  --player-highlight: rgba(148, 163, 184, 0.35);
  --player-glow: rgba(148, 163, 184, 0.52);
  --player-mark-glow: rgba(148, 163, 184, 0.5);
  background: linear-gradient(
    135deg,
    rgba(255, 255, 255, 0.82),
    rgba(226, 232, 240, 0.2)
  );
  color: #0f172a;
}

@media (prefers-color-scheme: dark) {
  .scoreboard__player--draw {
    --player-mark-color: #e2e8f0;
    --player-highlight: rgba(148, 163, 184, 0.32);
    --player-glow: rgba(148, 163, 184, 0.42);
    --player-mark-glow: rgba(148, 163, 184, 0.45);
    background: linear-gradient(
      135deg,
      rgba(30, 41, 59, 0.82),
      rgba(148, 163, 184, 0.18)
    );
    color: var(--surface-strong);
  }
}

.scoreboard__mark,
.scoreboard__name,
.scoreboard__score {
  position: relative;
  z-index: 1;
}

.scoreboard__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: clamp(44px, 6vw, 52px);
  height: clamp(44px, 6vw, 52px);
  border-radius: 14px;
  font-weight: 700;
  font-size: clamp(1rem, 2.4vw, 1.25rem);
  color: var(--player-mark-color);
  background: linear-gradient(
    135deg,
    var(--player-mark-glow),
    rgba(255, 255, 255, 0.08)
  );
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.35),
    0 0 18px var(--player-mark-glow);
  text-shadow: 0 0 12px var(--player-mark-glow);
}

.scoreboard__name {
  font-weight: 600;
  font-size: clamp(1.05rem, 2.5vw, 1.2rem);
  letter-spacing: 0.01em;
  min-width: 0;
  overflow-wrap: anywhere;
}

.scoreboard__score {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 4px;
  justify-self: end;
}

.scoreboard__score-value {
  font-weight: 700;
  font-size: clamp(1.4rem, 3vw, 1.75rem);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
  text-shadow: 0 0 14px var(--player-mark-glow);
}

@keyframes scoreboard-glow {
  0%,
  100% {
    opacity: 0.7;
    transform: scale(0.95);
  }

  50% {
    opacity: 0.95;
    transform: scale(1.05);
  }
}

.status {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 16px;
  border-radius: 999px;
  padding: 18px 28px 18px 24px;
  flex-wrap: wrap;
  background: linear-gradient(
    140deg,
    var(--glass-surface),
    var(--glass-surface-strong)
  );
  border: 1px solid var(--glass-border);
  font-size: 1.1rem;
  line-height: 1.5;
  font-weight: 600;
  color: var(--text);
  box-shadow: 0 22px 46px var(--glass-shadow);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  isolation: isolate;
  text-wrap: balance;
}

.status::before {
  content: "";
  width: 48px;
  height: 48px;
  border-radius: 18px;
  background: rgba(37, 99, 235, 0.18);
  background-repeat: no-repeat;
  background-position: center;
  background-size: 60%;
  box-shadow: 0 14px 30px var(--glow-accent);
  flex-shrink: 0;
}

.status::after {
  content: "";
  position: absolute;
  inset: -14px;
  z-index: -1;
  border-radius: inherit;
  background: radial-gradient(120% 120% at 15% 25%, var(--glow-accent), transparent);
  opacity: 0.85;
  filter: blur(6px);
}

.status[data-player="X"]::before {
  background-color: rgba(37, 99, 235, 0.2);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cline x1='5' y1='5' x2='19' y2='19' stroke='%232563eb' stroke-width='3.2' stroke-linecap='round'/%3E%3Cline x1='19' y1='5' x2='5' y2='19' stroke='%232563eb' stroke-width='3.2' stroke-linecap='round'/%3E%3C/svg%3E");
  box-shadow: 0 16px 34px var(--glow-accent);
}

.status[data-player="O"]::before {
  background-color: rgba(220, 38, 38, 0.18);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Ccircle cx='12' cy='12' r='7.5' stroke='%23dc2626' stroke-width='3' fill='none'/%3E%3C/svg%3E");
  box-shadow: 0 16px 34px var(--glow-danger);
}

.status[data-state="draw"]::before {
  background-color: rgba(139, 92, 246, 0.2);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6 9.5h12M6 14.5h12' stroke='%238b5cf6' stroke-width='3' stroke-linecap='round'/%3E%3C/svg%3E");
  box-shadow: 0 16px 34px var(--glow-neutral);
}

.status[data-state="draw"]::after {
  background: radial-gradient(120% 120% at 20% 20%, var(--glow-neutral), transparent);
}

.board {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(6px, 1.4vw, 10px);
  padding: clamp(12px, 2.5vw, 18px);
  width: 100%;
  max-width: 420px;
  margin-inline: auto;
  border-radius: 22px;
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.45), rgba(148, 163, 184, 0.25))
      padding-box,
    linear-gradient(160deg, rgba(37, 99, 235, 0.35), rgba(59, 130, 246, 0.05)) border-box;
  border: 1px solid transparent;
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.25), 0 6px 18px rgba(15, 23, 42, 0.18),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(18px) saturate(140%);
}

.board::after {
  content: "";
  position: absolute;
  inset: clamp(4px, 1vw, 10px);
  border-radius: inherit;
  opacity: 0;
  pointer-events: none;
  background: radial-gradient(
      circle at 50% 50%,
      var(--board-effect-accent, rgba(59, 130, 246, 0.28)),
      transparent 68%
    ),
    radial-gradient(
      circle at 50% 50%,
      var(--board-effect-secondary, rgba(56, 189, 248, 0.22)),
      transparent 75%
    );
  box-shadow: 0 0 42px var(--board-effect-color, rgba(59, 130, 246, 0.35));
  filter: blur(0.5px);
  transition: opacity 260ms ease, transform 260ms ease;
  transform: scale(0.96);
}

.board--celebrate::after,
.board--draw-flash::after {
  opacity: 1;
  transform: scale(1.04);
}

.board--celebrate {
  box-shadow: 0 22px 60px rgba(15, 23, 42, 0.3),
    0 0 0 2px rgba(255, 255, 255, 0.32),
    0 0 32px var(--board-effect-color, rgba(59, 130, 246, 0.35));
}

.board--draw-flash {
  box-shadow: 0 18px 45px rgba(15, 23, 42, 0.28),
    0 0 0 2px rgba(255, 255, 255, 0.28),
    0 0 32px var(--board-effect-color, rgba(129, 140, 248, 0.3));
}

.board--draw-flash::after {
  background: radial-gradient(
      circle at 40% 40%,
      var(--board-effect-accent, rgba(167, 139, 250, 0.26)),
      transparent 70%
    ),
    radial-gradient(
      circle at 60% 60%,
      var(--board-effect-secondary, rgba(129, 140, 248, 0.24)),
      transparent 78%
    );
}

.cell {
  --cell-mark-color: var(--surface-strong);
  --cell-glow-color: rgba(37, 99, 235, 0.2);
  --cell-reflection-opacity: 0.55;
  --cell-press-scale: 0.97;
  --cell-press-opacity: 0.92;
  --cell-focus-ring-color: color-mix(in srgb, var(--accent) 78%, rgba(255, 255, 255, 0.18));
  position: relative;
  aspect-ratio: 1 / 1;
  border-radius: 18px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  font-size: clamp(2.75rem, 9vw, 3.9rem);
  font-weight: 600;
  background: linear-gradient(160deg, rgba(17, 24, 39, 0.06), rgba(255, 255, 255, 0.08)),
    linear-gradient(320deg, rgba(255, 255, 255, 0.12), rgba(148, 163, 184, 0.08));
  color: var(--cell-mark-color);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.4),
    inset 0 -1px 4px rgba(15, 23, 42, 0.15);
  opacity: var(--cell-opacity, 1);
  transform: translateY(var(--cell-translate, 0)) scale(var(--cell-scale, 1));
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease,
    color 180ms ease, box-shadow 220ms ease, opacity 150ms ease;
}

.cell::before,
.cell::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  transition: opacity 220ms ease, transform 220ms ease;
}

.cell::before {
  background: linear-gradient(130deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0));
  mix-blend-mode: screen;
  opacity: var(--cell-reflection-opacity);
}

.cell::after {
  background: radial-gradient(circle at 25% 20%, rgba(255, 255, 255, 0.45), transparent 55%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.1), rgba(148, 163, 184, 0));
  opacity: calc(var(--cell-reflection-opacity) * 0.75);
}

.cell__glyph {
  position: relative;
  display: grid;
  place-items: center;
  width: 68%;
  height: 68%;
  pointer-events: none;
}

.cell__glyph::before {
  content: "";
  position: absolute;
  inset: 12%;
  border-radius: 22px;
  opacity: 0;
  transform: translateZ(0) scale(0.98);
  transition: opacity 220ms ease, transform 220ms ease, box-shadow 240ms ease;
  mix-blend-mode: screen;
}

.cell--x .cell__glyph::before {
  opacity: 0.9;
  transform: translateZ(0) scale(1);
  background: radial-gradient(
    circle at 50% 35%,
    color-mix(in srgb, var(--cell-x-color-soft) 70%, transparent) 0%,
    transparent 72%
  );
  box-shadow: 0 14px 26px color-mix(in srgb, var(--cell-x-color) 32%, transparent);
}

.cell--o .cell__glyph::before {
  opacity: 0.9;
  transform: translateZ(0) scale(1);
  background: radial-gradient(
    circle at 50% 35%,
    color-mix(in srgb, var(--cell-o-color-soft) 70%, transparent) 0%,
    transparent 72%
  );
  box-shadow: 0 14px 26px color-mix(in srgb, var(--cell-o-color) 32%, transparent);
}

.cell__icon {
  width: 100%;
  height: 100%;
  display: block;
  pointer-events: none;
  will-change: transform;
}

.cell--x .cell__icon--x {
  filter: drop-shadow(0 10px 18px color-mix(in srgb, var(--cell-x-color) 28%, transparent))
    drop-shadow(0 4px 10px var(--cell-glyph-shadow));
}

.cell--o .cell__icon--o {
  filter: drop-shadow(0 10px 18px color-mix(in srgb, var(--cell-o-color) 28%, transparent))
    drop-shadow(0 4px 10px var(--cell-glyph-shadow));
}

.cell:hover {
  --cell-translate: -2px;
  border-color: rgba(59, 130, 246, 0.65);
  box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.5),
    inset 0 -1px 6px rgba(15, 23, 42, 0.2), 0 8px 16px rgba(15, 23, 42, 0.12);
}

.cell:active {
  --cell-scale: var(--cell-press-scale);
  --cell-opacity: var(--cell-press-opacity);
}

.cell:focus-visible {
  outline: none;
  border-color: rgba(59, 130, 246, 0.75);
  box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.6),
    inset 0 -1px 6px rgba(15, 23, 42, 0.24), 0 0 0 3px rgba(255, 255, 255, 0.65),
    0 0 0 6px var(--cell-focus-ring-color);
}

.cell[aria-disabled="true"] {
  cursor: not-allowed;
  opacity: 0.75;
}

.cell--x {
  --cell-mark-color: var(--cell-x-color);
  --cell-glow-color: color-mix(in srgb, var(--cell-x-color) 50%, transparent);
  animation: cell-place 260ms cubic-bezier(0.2, 0.7, 0.35, 1.2);
}

.cell--o {
  --cell-mark-color: var(--cell-o-color);
  --cell-glow-color: color-mix(in srgb, var(--cell-o-color) 55%, transparent);
  animation: cell-place 260ms cubic-bezier(0.2, 0.7, 0.35, 1.2);
}

.cell--winner {
  --cell-reflection-opacity: 0.75;
  border-color: rgba(59, 130, 246, 0.65);
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.45), 0 0 24px rgba(59, 130, 246, 0.35),
    inset 0 0 12px rgba(59, 130, 246, 0.2);
  animation: cell-winner-pulse 1.8s ease-in-out infinite;
}

.cell--winner::after {
  background: conic-gradient(
      from 0deg,
      rgba(59, 130, 246, 0.0) 0deg,
      rgba(59, 130, 246, 0.35) 120deg,
      rgba(59, 130, 246, 0.6) 180deg,
      rgba(59, 130, 246, 0.0) 300deg
    ),
    radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.35), transparent 65%);
  animation: cell-winner-sheen 2.6s linear infinite;
  opacity: 0.9;
  mix-blend-mode: screen;
}

.cell--x,
.cell--o {
  text-shadow: 0 0 14px var(--cell-glow-color), 0 0 28px color-mix(in srgb, var(--cell-glow-color) 70%, transparent);
}

@keyframes cell-place {
  0% {
    transform: scale(0.75);
    filter: blur(6px);
    opacity: 0;
  }

  60% {
    transform: scale(1.05);
    filter: blur(0);
    opacity: 1;
  }

  100% {
    transform: scale(1);
    filter: blur(0);
    opacity: 1;
  }
}

@keyframes cell-winner-pulse {
  0%,
  100% {
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.45), 0 0 24px rgba(59, 130, 246, 0.35),
      inset 0 0 12px rgba(59, 130, 246, 0.2);
  }

  50% {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.65), 0 0 36px rgba(59, 130, 246, 0.45),
      inset 0 0 18px rgba(59, 130, 246, 0.32);
  }
}

@keyframes cell-winner-sheen {
  0% {
    transform: rotate(0deg);
  }

  100% {
    transform: rotate(360deg);
  }
}

@media (prefers-reduced-motion: reduce) {
  .cell,
  .cell::before,
  .cell::after {
    transition-duration: 0.01ms !important;
  }

  .cell--x,
  .cell--o,
  .cell--winner {
    animation: none !important;
  }
}

.play-area {
  display: grid;
  gap: 24px;
  align-content: start;
  min-height: clamp(360px, 52vh, 520px);
  padding-block-end: clamp(2rem, 3vw, 3.25rem);
}

.controls {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 20px;
  border-radius: 24px;
  background: linear-gradient(135deg, var(--glass-surface), var(--glass-surface-strong));
  border: 1px solid var(--glass-border);
  box-shadow: 0 24px 48px var(--glass-shadow);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  flex-wrap: wrap;
  isolation: isolate;
}

.controls::after {
  content: "";
  position: absolute;
  inset: -18px;
  z-index: -1;
  border-radius: inherit;
  background: radial-gradient(160% 120% at 50% 100%, rgba(37, 99, 235, 0.18), transparent);
  filter: blur(10px);
  opacity: 0.9;
}

.controls__group {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

@media (prefers-color-scheme: dark) {
  .controls__group {
    background: rgba(17, 24, 39, 0.35);
    box-shadow: inset 0 0 0 1px rgba(148, 163, 184, 0.18);
  }
}

.controls .button {
  min-width: 150px;
}

.toolbar__actions .button,
.controls .button {
  transition: transform 200ms ease, box-shadow 220ms ease, background 200ms ease,
    color 200ms ease, border-color 200ms ease;
}

.toolbar__actions .button:hover,
.controls .button:hover {
  transform: translateY(-2px) scale(1.01);
}

.toolbar__actions .button:active,
.controls .button:active {
  transform: translateY(0);
}

.controls .button.button--ghost:hover {
  background: rgba(37, 99, 235, 0.12);
}

.controls .button.button--ghost:active {
  background: rgba(37, 99, 235, 0.18);
}

.play-area .board {
  margin-block-end: clamp(1.25rem, 2vw, 2.25rem);
}

@keyframes modal-fade-in {
  0% {
    opacity: 0;
    transform: translate3d(0, 28px, 0) scale(0.96);
    filter: drop-shadow(0 18px 44px rgba(15, 23, 42, 0.32));
  }

  100% {
    opacity: 1;
    transform: translate3d(0, 0, 0) scale(1);
    filter: drop-shadow(0 32px 60px var(--glass-shadow));
  }
}

@keyframes modal-fade-out {
  0% {
    opacity: 1;
    transform: translate3d(0, 0, 0) scale(1);
    filter: drop-shadow(0 32px 60px var(--glass-shadow));
  }

  100% {
    opacity: 0;
    transform: translate3d(0, 22px, 0) scale(0.96);
    filter: drop-shadow(0 12px 32px rgba(15, 23, 42, 0.22));
  }
}

@keyframes modal-backdrop-fade-in {
  0% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

@keyframes modal-backdrop-fade-out {
  0% {
    opacity: 1;
  }

  100% {
    opacity: 0;
  }
}

dialog {
  border: none;
  border-radius: 20px;
  padding: 0;
  max-width: min(460px, 92vw);
  background: transparent;
  color: inherit;
  opacity: 0;
  transform: translate3d(0, 28px, 0) scale(0.98);
  filter: drop-shadow(0 32px 60px var(--glass-shadow));
  pointer-events: none;
}

dialog[open] {
  opacity: 1;
  transform: translate3d(0, 0, 0) scale(1);
  pointer-events: auto;
}

dialog.modal--entering {
  animation: modal-fade-in 320ms cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

dialog.modal--open {
  opacity: 1;
  transform: translate3d(0, 0, 0) scale(1);
  pointer-events: auto;
  filter: drop-shadow(0 32px 60px var(--glass-shadow));
}

dialog.modal--leaving,
dialog.is-closing {
  animation: modal-fade-out 260ms cubic-bezier(0.33, 1, 0.68, 1) forwards;
  pointer-events: none;
}

dialog::backdrop {
  background:
    radial-gradient(circle at top, rgba(148, 163, 184, 0.22), transparent 60%),
    rgba(15, 23, 42, 0.48);
  backdrop-filter: blur(6px);
  opacity: 0;
}

dialog[open]::backdrop {
  opacity: 1;
}

dialog.modal--entering::backdrop {
  animation: modal-backdrop-fade-in 260ms ease forwards;
}

dialog.modal--open::backdrop {
  opacity: 1;
}

dialog.modal--leaving::backdrop,
dialog.is-closing::backdrop {
  animation: modal-backdrop-fade-out 220ms ease forwards;
}

@media (prefers-reduced-motion: reduce) {
  dialog,
  dialog::backdrop {
    animation: none !important;
    transition: none;
  }

  dialog {
    transform: none;
    opacity: 1;
  }
}

.modal {
  position: relative;
  display: flex;
  flex-direction: column;
  border-radius: 20px;
  padding: 0;
  --modal-padding-inline: clamp(1.25rem, 1.5vw + 1rem, 1.75rem);
  --modal-section-gap: clamp(1rem, 1vw + 0.75rem, 1.5rem);
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.25), transparent 60%),
    var(--glass-overlay);
  backdrop-filter: blur(26px) saturate(165%);
  border: 1px solid var(--glass-outline);
  box-shadow:
    inset 0 1px 0 var(--modal-edge-light),
    0 14px 40px var(--glass-shadow);
  overflow: hidden;
}

.modal::before,
.modal::after {
  content: "";
  position: absolute;
  inset: 1px;
  border-radius: inherit;
  pointer-events: none;
}

.modal::before {
  border: 1px solid rgba(255, 255, 255, 0.16);
  mix-blend-mode: screen;
  opacity: 0.4;
}

.modal::after {
  background: linear-gradient(180deg, transparent 0%, rgba(255, 255, 255, 0.08) 100%);
  opacity: 0.35;
}

.modal__header {
  padding: clamp(0.9rem, 1vw + 0.6rem, 1.35rem) var(--modal-padding-inline)
    clamp(0.7rem, 0.9vw + 0.5rem, 1.1rem);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  box-shadow: inset 0 -1px 0 var(--divider);
}

.modal__title {
  margin: 0;
  font-size: clamp(1.2rem, 1.1vw + 1rem, 1.45rem);
  font-weight: 650;
}

.modal__body {
  padding: clamp(0.9rem, 1vw + 0.65rem, 1.35rem) var(--modal-padding-inline)
    clamp(0.4rem, 0.8vw + 0.35rem, 0.9rem);
  display: flex;
  flex-direction: column;
  gap: var(--modal-section-gap);
}

.modal__footer {
  padding: clamp(0.7rem, 0.9vw + 0.5rem, 1.1rem) var(--modal-padding-inline)
    clamp(1rem, 1vw + 0.75rem, 1.35rem);
  display: flex;
  justify-content: flex-end;
  gap: clamp(0.5rem, 1vw, 0.75rem);
  flex-wrap: wrap;
  box-shadow: inset 0 1px 0 var(--divider);
}

.field {
  display: flex;
  flex-direction: column;
  gap: clamp(0.5rem, 1vw, 0.75rem);
}

.field label {
  font-weight: 600;
  font-size: 0.95rem;
}

.field__control {
  position: relative;
  display: flex;
  align-items: center;
  border-radius: 999px;
  background: var(--field-bg);
  border: 1px solid var(--field-border);
  box-shadow: 0 12px 28px var(--field-shadow), inset 0 1px 0 rgba(255, 255, 255, 0.25);
  transition:
    border-color 200ms ease,
    box-shadow 200ms ease,
    background 200ms ease;
}

.field__control::after {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  border: 1px solid rgba(255, 255, 255, 0.35);
  opacity: 0.6;
  pointer-events: none;
}

.field__control input[type="text"] {
  flex: 1;
  border: none;
  background: transparent;
  padding: clamp(0.65rem, 1.6vw, 0.85rem) clamp(1.1rem, 2.2vw, 1.5rem);
  font: inherit;
  color: inherit;
  border-radius: inherit;
  min-width: 0;
}

.field__control input[type="text"]::placeholder {
  color: var(--text-secondary);
  color: color-mix(in srgb, var(--text-secondary) 68%, transparent);
}

.field__control input[type="text"]:focus-visible {
  outline: none;
}

.field__control input[type="text"]:focus-visible + .field__status,
.field__control input[type="text"].is-invalid + .field__status,
.field__control input[type="text"]:not(:placeholder-shown):not(.is-invalid) + .field__status {
  opacity: 1;
  transform: scale(1);
}

.field__control input[type="text"]:focus-visible + .field__status {
  color: var(--accent);
}

.field__control:focus-within {
  border-color: var(--accent);
  box-shadow:
    0 12px 28px var(--field-shadow),
    0 0 0 1px var(--accent-ring),
    0 0 0 8px var(--accent-ring-outer);
  background: var(--field-focus-bg);
}

.field__control input[type="text"].is-invalid {
  color: var(--danger);
}

.field__control:has(input.is-invalid),
.field__control.is-invalid {
  border-color: var(--danger);
  box-shadow:
    0 12px 28px var(--field-shadow),
    0 0 0 1px var(--danger-ring),
    0 0 0 8px var(--danger-ring-outer);
}

.field__status {
  position: absolute;
  right: clamp(0.9rem, 2vw, 1.25rem);
  width: 1.1rem;
  height: 1.1rem;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 200ms ease, transform 200ms ease;
  background-repeat: no-repeat;
  background-position: center;
  background-size: 100%;
  filter: drop-shadow(0 4px 10px rgba(15, 23, 42, 0.2));
}

.field__control input[type="text"].is-invalid + .field__status {
  color: var(--danger);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Ccircle cx='10' cy='10' r='9' stroke='currentColor' stroke-width='2'/%3E%3Cpath stroke='currentColor' stroke-linecap='round' stroke-width='2' d='M10 5v6m0 4h.01'/%3E%3C/svg%3E");
}

.field__control input[type="text"]:not(:placeholder-shown):not(.is-invalid) + .field__status {
  color: var(--accent);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Cpath stroke='currentColor' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M5.5 10.5 8.5 13.5 14.5 7.5'/%3E%3C/svg%3E");
}

.field.field--segmented,
.field.field--swatches {
  border: none;
  padding: 0;
  min-inline-size: 0;
}

.field__legend {
  font-weight: 600;
  font-size: 0.95rem;
}

.field--segmented,
.field--swatches {
  gap: clamp(0.6rem, 0.8vw, 0.85rem);
}

.segmented-control {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(12.5rem, 1fr));
  gap: clamp(0.45rem, 0.6vw, 0.75rem);
  padding: clamp(0.35rem, 0.5vw, 0.65rem);
  border-radius: clamp(0.9rem, 1vw, 1.1rem);
  background: var(--control-bg);
  border: 1px solid var(--control-border);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.28), var(--control-shadow);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.segmented-control__option {
  position: relative;
  display: block;
}

.segmented-control__input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  pointer-events: none;
}

.segmented-control__label {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.3rem;
  padding: clamp(0.7rem, 0.9vw, 0.95rem) clamp(0.9rem, 1vw + 0.75rem, 1.35rem);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  border-radius: clamp(0.75rem, 0.9vw, 1rem);
  border: 1px solid transparent;
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.25),
    inset 0 0 0 1px rgba(255, 255, 255, 0.1),
    0 12px 24px rgba(15, 23, 42, 0.12);
  transition:
    background 200ms ease,
    border-color 200ms ease,
    color 200ms ease,
    box-shadow 220ms ease,
    transform 220ms ease;
  min-height: 100%;
}

.segmented-control__option:hover .segmented-control__label {
  background: color-mix(in srgb, var(--surface) 82%, transparent);
  transform: translateY(-1px);
}

.segmented-control__input:focus-visible + .segmented-control__label {
  outline: 3px solid var(--accent-ring);
  outline-offset: 3px;
}

.segmented-control__input:checked + .segmented-control__label {
  border-color: var(--accent-ring);
  background: var(--control-selected-bg);
  color: var(--surface-strong);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.35),
    inset 0 0 0 1px color-mix(in srgb, var(--accent) 35%, transparent),
    0 18px 36px color-mix(in srgb, var(--accent) 25%, rgba(15, 23, 42, 0.2));
  transform: translateY(-1px);
}

.segmented-control__title {
  font-weight: 600;
  font-size: clamp(0.95rem, 0.4vw + 0.9rem, 1.05rem);
}

.segmented-control__description {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.segmented-control__input:checked + .segmented-control__label .segmented-control__description {
  color: color-mix(in srgb, var(--surface-strong) 65%, transparent);
}

.swatch-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(9.5rem, 1fr));
  gap: clamp(0.5rem, 0.65vw, 0.85rem);
}

.swatch {
  position: relative;
  display: block;
  cursor: pointer;
}

.swatch__input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  pointer-events: none;
}

.swatch__content {
  display: flex;
  align-items: center;
  gap: clamp(0.45rem, 0.5vw, 0.65rem);
  padding: clamp(0.6rem, 0.7vw, 0.85rem) clamp(0.85rem, 1vw, 1.15rem);
  border-radius: 999px;
  background: color-mix(in srgb, var(--surface) 90%, transparent);
  border: 1px solid var(--control-border);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.24),
    inset 0 0 0 1px rgba(255, 255, 255, 0.08),
    0 14px 28px rgba(15, 23, 42, 0.14);
  transition:
    background 200ms ease,
    border-color 200ms ease,
    box-shadow 200ms ease,
    transform 200ms ease;
}

.swatch:hover .swatch__content {
  transform: translateY(-1px);
  background: color-mix(in srgb, var(--surface) 84%, transparent);
}

.swatch__input:focus-visible + .swatch__content {
  outline: 3px solid var(--accent-ring);
  outline-offset: 3px;
}

.swatch__input:checked + .swatch__content {
  border-color: var(--accent-ring);
  background: var(--control-selected-bg);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.35),
    inset 0 0 0 1px color-mix(in srgb, var(--accent) 34%, transparent),
    0 18px 34px color-mix(in srgb, var(--accent) 26%, rgba(15, 23, 42, 0.22));
}

.swatch__visual {
  --swatch-color: var(--accent);
  width: clamp(1.4rem, 0.9vw + 1.1rem, 1.75rem);
  height: clamp(1.4rem, 0.9vw + 1.1rem, 1.75rem);
  border-radius: 999px;
  background: radial-gradient(
      circle at 30% 30%,
      rgba(255, 255, 255, 0.55),
      transparent 58%
    ),
    linear-gradient(140deg,
      color-mix(in srgb, var(--swatch-color) 92%, transparent) 0%,
      color-mix(in srgb, var(--swatch-color) 70%, transparent) 100%);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.55),
    0 12px 18px color-mix(in srgb, var(--swatch-color) 35%, rgba(15, 23, 42, 0.32));
}

.swatch__label {
  font-weight: 600;
  color: var(--text);
}

.swatch__input:checked + .swatch__content .swatch__label {
  color: var(--surface-strong);
}

.swatch[data-accent-option="sky"] {
  --swatch-color: #2563eb;
}

.swatch[data-accent-option="violet"] {
  --swatch-color: #8b5cf6;
}

.swatch[data-accent-option="emerald"] {
  --swatch-color: #10b981;
}

.swatch[data-accent-option="amber"] {
  --swatch-color: #f59e0b;
}

.swatch[data-accent-option="rose"] {
  --swatch-color: #f43f5e;
}

.field__hint {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.field__error {
  font-size: 0.85rem;
  color: var(--danger);
}

.effect-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 24;
  mix-blend-mode: screen;
  isolation: isolate;
  opacity: 1;
  transition: opacity 260ms ease;
}

.effect-overlay--fade-out {
  opacity: 0;
}

.effect-overlay__canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.effect-overlay__radial {
  position: absolute;
  left: var(--glow-center-x, 50%);
  top: var(--glow-center-y, 50%);
  width: var(--glow-size, 320px);
  height: var(--glow-size, 320px);
  transform: translate(-50%, -50%);
  border-radius: 50%;
  background: radial-gradient(
      circle at 50% 50%,
      var(--effect-tone-accent, rgba(59, 130, 246, 0.32)),
      transparent 58%
    ),
    radial-gradient(
      circle at 50% 50%,
      var(--effect-tone-secondary, rgba(96, 165, 250, 0.28)),
      transparent 85%
    );
  box-shadow: 0 0 65px var(--effect-tone-color, rgba(59, 130, 246, 0.38));
  filter: blur(0.5px);
  opacity: 0.95;
  animation: radial-glow-burst var(--glow-duration, 1200ms) ease-out forwards;
}

.effect-overlay__particle-field {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.effect-overlay__particle {
  position: absolute;
  left: var(--particle-start-x, 50%);
  top: var(--particle-start-y, 50%);
  border-radius: 999px;
  background:
    radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.9), transparent 70%),
    radial-gradient(circle at 50% 50%, var(--effect-tone-accent, rgba(167, 139, 250, 0.45)), transparent 85%);
  box-shadow: 0 10px 22px rgba(15, 23, 42, 0.18);
  mix-blend-mode: screen;
  opacity: 0;
  transform: translate3d(0, 0, 0) scale(0.55);
  animation: particle-float var(--particle-duration, 1400ms) ease-out forwards;
  animation-delay: var(--particle-delay, 0ms);
}

@keyframes radial-glow-burst {
  0% {
    opacity: 0.95;
    transform: translate(-50%, -50%) scale(0.75);
    filter: blur(0px);
  }
  55% {
    opacity: 0.8;
  }
  100% {
    opacity: 0;
    transform: translate(-50%, -50%) scale(1.6);
    filter: blur(18px);
  }
}

@keyframes particle-float {
  0% {
    opacity: 0;
    transform: translate3d(0, 0, 0) scale(0.45);
  }
  25% {
    opacity: 0.95;
  }
  100% {
    opacity: 0;
    transform: translate3d(var(--particle-dx, 0px), var(--particle-dy, -24px), 0)
      scale(0.1);
  }
}

@media (max-width: 600px) {
  .app-shell {
    padding: 20px 16px 36px;
  }

  .controls {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .controls__group {
    width: 100%;
    justify-content: center;
  }

  .controls .button {
    width: min(100%, 240px);
  }
}

@media (prefers-reduced-motion: reduce) {
  button,
  .button,
  .controls .button,
  .toolbar__actions .button,
  .status,
  .board,
  .board::after {
  .segmented-control__label,
  .swatch__content,
  .swatch__visual {
    transition: none;
  }

  .button:hover,
  .button:active,
  .controls .button:hover,
  .controls .button:active,
  .toolbar__actions .button:hover,
  .toolbar__actions .button:active,
  .segmented-control__option:hover .segmented-control__label,
  .swatch:hover .swatch__content {
    transform: none;
  }

  .board--celebrate,
  .board--draw-flash {
    box-shadow: 0 0 0 2px var(--board-effect-color, rgba(148, 163, 184, 0.25));
  }
}