/* T9 Chess interactive demo — keypad phone mockup with a D-pad driven board */
.t9-demo {
  display: flex;
  flex-wrap: wrap;
  gap: 1.75rem;
  align-items: flex-start;
  margin: 2rem 0;
}

/* phone body */
.t9-phone {
  width: 264px;
  flex-shrink: 0;
  background: linear-gradient(#222428, #16181c);
  border: 1px solid #34383f;
  border-radius: 22px;
  padding: 16px 14px 18px;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.55), inset 0 1px 0 rgba(255, 255, 255, 0.05);
  outline: none;
}
.t9-phone:focus-visible { border-color: var(--accent); }

/* screen */
.t9-screen {
  background: #1a1d22;
  border: 1px solid #3a3f47;
  border-radius: 8px;
  padding: 10px;
  margin-bottom: 16px;
  box-shadow: inset 0 1px 4px rgba(0, 0, 0, 0.5);
}
.t9-status {
  font-size: 0.6rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 6px;
  min-height: 1em;
}
.t9-status.is-over { color: var(--accent); }

/* board */
.t9-board {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  grid-template-rows: repeat(8, 1fr);
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 3px;
  overflow: hidden;
  box-shadow: 0 0 0 1px #3a4048, inset 0 0 0 1px rgba(0, 0, 0, 0.2);
}
.t9-sq {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  line-height: 1;
  user-select: none;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
.t9-sq--light { background: #a9b1bc; }
.t9-sq--dark { background: #6c7681; }
.t9-sq--white {
  color: #fcfcfc;
  text-shadow: 0 1px 1px rgba(0, 0, 0, 0.55), 0 0 1px rgba(0, 0, 0, 0.4);
}
.t9-sq--black {
  color: #15181c;
  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.22);
}
.t9-sq.is-cursor { box-shadow: inset 0 0 0 3px var(--accent); z-index: 1; }
.t9-sq.is-selected { box-shadow: inset 0 0 0 3px #5fb36a; z-index: 1; }
.t9-sq.is-check { box-shadow: inset 0 0 0 3px #d4795f; z-index: 1; }
.t9-sq.is-target::after {
  content: "";
  position: absolute;
  width: 32%;
  height: 32%;
  border-radius: 50%;
  background: rgba(95, 179, 106, 0.75);
}

/* keypad */
.t9-keys { display: flex; justify-content: center; }
.t9-dpad {
  display: grid;
  grid-template-columns: repeat(3, 52px);
  grid-template-rows: repeat(3, 42px);
  gap: 6px;
}
.t9-key {
  font-family: var(--font);
  font-size: 0.78rem;
  color: var(--muted);
  background: linear-gradient(#242424, #181818);
  border: 1px solid var(--border-strong);
  border-radius: 8px;
  cursor: pointer;
  transition: color 0.12s ease, border-color 0.12s ease;
}
.t9-key:hover { color: var(--fg); border-color: var(--faint); }
.t9-key:active { background: #101010; transform: translateY(1px); }
.t9-key--up { grid-column: 2; grid-row: 1; }
.t9-key--left { grid-column: 1; grid-row: 2; }
.t9-key--ok {
  grid-column: 2;
  grid-row: 2;
  font-size: 0.68rem;
  color: var(--accent);
  border-color: var(--accent);
}
.t9-key--right { grid-column: 3; grid-row: 2; }
.t9-key--down { grid-column: 2; grid-row: 3; }

.t9-brand {
  text-align: center;
  font-size: 0.58rem;
  letter-spacing: 0.32em;
  color: var(--faint);
  margin-top: 14px;
}

/* side panel */
.t9-demo__side { flex: 1; min-width: 190px; padding-top: 3rem; }
.t9-demo__hint {
  font-size: 0.78rem;
  line-height: 1.65;
  color: var(--faint);
  margin: 0 0 1.1rem;
}
.t9-demo__hint b { color: var(--muted); font-weight: 600; }
.t9-reset {
  font-family: var(--font);
  font-size: 0.78rem;
  color: var(--muted);
  background: transparent;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 0.4rem 0.7rem;
  cursor: pointer;
  transition: color 0.15s ease, border-color 0.15s ease;
}
.t9-reset:hover { color: var(--fg); border-color: var(--faint); }

@media (max-width: 560px) {
  .t9-demo { justify-content: center; }
  .t9-demo__side { padding-top: 0; }
}