/* ── Reset & Base ─────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0a0e1a;
  --surface: #131929;
  --surface2: #1c2540;
  --accent: #4fc3f7;
  --accent2: #81d4fa;
  --success: #69f0ae;
  --danger: #ff5252;
  --warn: #ffca28;
  --text: #e8eaf6;
  --text-dim: #90a4ae;
  --radius: 12px;
  --shadow: 0 8px 32px rgba(0,0,0,.5);
}

html, body {
  width: 100%; height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  overflow: hidden;
  user-select: none;
}

/* ── Screens ──────────────────────────────────────── */
.screen {
  position: fixed; inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
}
.screen.active { display: flex; }
.screen.overlay {
  background: rgba(0,0,0,.7);
  backdrop-filter: blur(6px);
  z-index: 100;
}

/* ── Menu ─────────────────────────────────────────── */
#screen-menu { overflow-y: auto; }

.menu-bg {
  position: fixed; inset: 0;
  background: radial-gradient(ellipse at 50% 30%, #0d2b5e 0%, #0a0e1a 70%);
  z-index: 0;
}

.stars {
  position: absolute; inset: 0;
  overflow: hidden;
}
.star {
  position: absolute;
  background: #fff;
  border-radius: 50%;
  animation: twinkle var(--dur, 3s) ease-in-out infinite alternate;
  opacity: var(--op, 0.6);
}
@keyframes twinkle {
  from { opacity: var(--op, 0.6); transform: scale(1); }
  to   { opacity: 0.1; transform: scale(0.5); }
}

.menu-content {
  position: relative; z-index: 1;
  display: flex; flex-direction: column;
  align-items: center; gap: 28px;
  padding: 48px 24px;
  width: 100%; max-width: 560px;
}

.logo { text-align: center; }
.tux-logo { font-size: 80px; animation: float 3s ease-in-out infinite; }
@keyframes float {
  0%,100% { transform: translateY(0); }
  50%      { transform: translateY(-12px); }
}
.logo h1 {
  font-size: 3rem; font-weight: 800;
  background: linear-gradient(135deg, var(--accent), var(--success));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  letter-spacing: 2px;
}
.logo .subtitle { color: var(--text-dim); font-size: .9rem; letter-spacing: 4px; margin-top: 4px; }

.difficulty-select { width: 100%; }
.difficulty-select h2 { text-align: center; font-size: 1rem; color: var(--text-dim); margin-bottom: 14px; letter-spacing: 2px; text-transform: uppercase; }

.diff-buttons { display: flex; gap: 10px; }
.diff-btn {
  flex: 1; display: flex; flex-direction: column; align-items: center; gap: 4px;
  padding: 14px 8px; border: 2px solid var(--surface2);
  background: var(--surface); border-radius: var(--radius);
  cursor: pointer; color: var(--text); transition: all .2s;
}
.diff-btn:hover { border-color: var(--accent); background: var(--surface2); }
.diff-btn.active { border-color: var(--accent); background: rgba(79,195,247,.1); }
.diff-icon { font-size: 1.8rem; }
.diff-name { font-weight: 700; font-size: .95rem; }
.diff-desc { font-size: .7rem; color: var(--text-dim); text-align: center; }

.btn-primary, .btn-secondary, .btn-tertiary {
  width: 100%; max-width: 320px; padding: 14px 24px;
  font-size: 1rem; font-weight: 700; border: none; border-radius: var(--radius);
  cursor: pointer; transition: all .2s; letter-spacing: 1px;
}
.btn-primary {
  background: linear-gradient(135deg, #1565c0, #0288d1);
  color: #fff; box-shadow: 0 4px 20px rgba(2,136,209,.4);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 28px rgba(2,136,209,.6); }
.btn-secondary {
  background: var(--surface2); color: var(--text);
  border: 1px solid rgba(255,255,255,.1);
}
.btn-secondary:hover { background: #263050; }
.btn-tertiary {
  background: transparent; color: var(--text-dim);
  border: 1px solid rgba(255,255,255,.1);
}
.btn-tertiary:hover { color: var(--text); }

/* ── Secret Code UI ───────────────────────────────── */
#secret-code-wrap {
  width: 100%; display: flex; flex-direction: column; align-items: center; gap: 10px;
}
#secret-code-toggle {
  font-size: 1.4rem; cursor: pointer; opacity: .4; transition: opacity .2s, transform .3s;
  user-select: none;
}
#secret-code-toggle:hover { opacity: .8; transform: scale(1.2); }
#secret-code-toggle.open { opacity: 1; }

#secret-code-panel {
  width: 100%; max-width: 320px;
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center; justify-content: center;
}
#secret-code-input {
  flex: 1; min-width: 160px; padding: 10px 14px;
  background: var(--surface2); border: 1px solid rgba(255,255,255,.1);
  border-radius: 10px; color: var(--text); font-size: .95rem; outline: none;
  letter-spacing: 2px; text-align: center;
  transition: border-color .2s;
}
#secret-code-input:focus { border-color: rgba(255,255,255,.3); }
#btn-secret-submit {
  padding: 10px 18px; background: var(--surface2);
  border: 1px solid rgba(255,255,255,.15); border-radius: 10px;
  color: var(--text); font-size: .9rem; cursor: pointer; transition: background .2s;
}
#btn-secret-submit:hover { background: #263050; }
#secret-feedback {
  width: 100%; text-align: center; font-size: .85rem; min-height: 1.2em;
  transition: color .2s;
}
#secret-feedback.success { color: var(--success); }
#secret-feedback.fail    { color: var(--danger); }

/* ── Secret Levels Section ────────────────────────── */
.secret-levels-title {
  text-align: center; color: var(--warn); font-size: .85rem;
  letter-spacing: 2px; text-transform: uppercase; margin-bottom: 10px;
}
#secret-levels-list { display: flex; flex-direction: column; gap: 8px; width: 100%; }

.secret-level-btn {
  width: 100%; display: flex; align-items: center; gap: 14px;
  padding: 12px 16px;
  background: linear-gradient(135deg, rgba(255,202,40,.08), rgba(255,152,0,.05));
  border: 1px solid rgba(255,202,40,.3); border-radius: var(--radius);
  color: var(--text); cursor: pointer; transition: all .2s;
  font-size: .95rem;
}
.secret-level-btn:hover {
  border-color: var(--warn);
  background: linear-gradient(135deg, rgba(255,202,40,.15), rgba(255,152,0,.1));
  transform: translateY(-1px);
}
.secret-level-btn .sl-icon { font-size: 1.6rem; }
.secret-level-btn .sl-info { display: flex; flex-direction: column; gap: 2px; text-align: left; }
.secret-level-btn .sl-name { font-weight: 700; }
.secret-level-btn .sl-desc { font-size: .75rem; color: var(--text-dim); }

.highscores-preview { width: 100%; }
.highscores-preview h3 { text-align: center; color: var(--text-dim); font-size: .85rem; letter-spacing: 2px; text-transform: uppercase; margin-bottom: 10px; }
#menu-scores {
  list-style: none; display: flex; flex-direction: column; gap: 6px;
}
#menu-scores li {
  display: flex; justify-content: space-between; align-items: center;
  padding: 8px 14px; background: var(--surface); border-radius: 8px;
  font-size: .9rem;
}
#menu-scores li:first-child { border: 1px solid rgba(255,202,40,.3); }
.hs-rank { color: var(--warn); font-weight: 700; min-width: 24px; }
.hs-name { flex: 1; margin: 0 12px; }
.hs-score { color: var(--accent); font-weight: 700; }

/* ── Game Canvas ──────────────────────────────────── */
#screen-game { background: var(--bg); }

#game-canvas {
  display: block;
  width: 100%; height: 100%;
  image-rendering: pixelated;
}

/* ── HUD ──────────────────────────────────────────── */
#hud {
  position: fixed; top: 0; left: 0; right: 0;
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px 20px;
  background: rgba(10,14,26,.8);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(255,255,255,.07);
  z-index: 10;
}
.hud-label { display: block; font-size: .65rem; color: var(--text-dim); letter-spacing: 2px; text-transform: uppercase; }
#hud-score, #hud-level, #hud-lives { font-size: 1.3rem; font-weight: 800; }
#hud-score { color: var(--accent); }
#hud-level { color: var(--success); }
.hud-center { text-align: center; }
.hud-right  { text-align: right; }

/* ── Input Bar ────────────────────────────────────── */
#input-bar {
  position: fixed; bottom: 16px; left: 50%; transform: translateX(-50%);
  display: flex; align-items: center; gap: 6px;
  background: rgba(19,25,41,.9);
  border: 2px solid var(--accent);
  border-radius: 40px;
  padding: 10px 22px;
  font-size: 1.4rem; font-weight: 700;
  min-width: 260px; max-width: 480px;
  box-shadow: 0 0 30px rgba(79,195,247,.2);
  z-index: 10;
}
#input-prefix { color: var(--accent); font-size: 1rem; }
#input-display { color: var(--text); letter-spacing: 2px; min-width: 4ch; }
.cursor { color: var(--accent); }
.blink { animation: blink .8s step-end infinite; }
@keyframes blink { 50% { opacity: 0; } }

/* ── Combo ────────────────────────────────────────── */
#combo-display {
  position: fixed; top: 60px; right: 16px;
  font-size: 1.1rem; font-weight: 800;
  color: var(--warn);
  text-shadow: 0 0 12px var(--warn);
  opacity: 0; transition: opacity .3s;
  z-index: 10;
}
#combo-display.show { opacity: 1; }

/* ── Pause button ─────────────────────────────────── */
#btn-pause {
  position: fixed; top: 12px; right: 60px;
  background: none; border: none;
  font-size: 1.3rem; cursor: pointer;
  opacity: .5; z-index: 20; padding: 4px;
}
#btn-pause:hover { opacity: 1; }

/* ── Modal ────────────────────────────────────────── */
.modal {
  background: var(--surface);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: 20px;
  padding: 40px 32px;
  display: flex; flex-direction: column; align-items: center; gap: 16px;
  width: 90%; max-width: 420px;
  box-shadow: var(--shadow);
}
.modal h2 { font-size: 1.8rem; margin-bottom: 4px; }

.result-icon { font-size: 4rem; }

.final-stats {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 12px; width: 100%; margin: 8px 0;
}
.stat {
  background: var(--surface2); border-radius: 10px;
  padding: 12px; text-align: center;
  display: flex; flex-direction: column; gap: 4px;
}
.stat span { font-size: .7rem; color: var(--text-dim); text-transform: uppercase; letter-spacing: 1px; }
.stat strong { font-size: 1.4rem; color: var(--accent); }

#new-highscore-badge {
  background: linear-gradient(135deg, #f57f17, #ffca28);
  color: #000; font-weight: 800;
  padding: 8px 20px; border-radius: 30px;
  font-size: .9rem; letter-spacing: 1px;
  animation: pulse-badge .6s ease-in-out infinite alternate;
}
@keyframes pulse-badge {
  from { transform: scale(1); }
  to   { transform: scale(1.05); }
}
.hidden { display: none !important; }

#name-input {
  width: 100%; padding: 12px 16px;
  background: var(--surface2); border: 1px solid rgba(255,255,255,.15);
  border-radius: 10px; color: var(--text);
  font-size: 1rem; outline: none;
}
#name-input:focus { border-color: var(--accent); }

/* ── Practice ─────────────────────────────────────── */
#screen-practice {
  background: var(--bg);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0;
}

#practice-container {
  width: 90%; max-width: 640px;
  display: flex; flex-direction: column; gap: 32px;
}

#practice-header {
  display: flex; justify-content: space-between; align-items: center;
}
#practice-header h2 { font-size: 1.4rem; }

#practice-word-display {
  background: var(--surface); border-radius: var(--radius);
  padding: 40px; text-align: center;
  border: 1px solid rgba(255,255,255,.07);
}

#practice-word {
  font-size: 2.8rem; font-weight: 800; letter-spacing: 6px;
  min-height: 3rem;
  font-family: 'Courier New', monospace;
}
#practice-word .typed { color: var(--success); }
#practice-word .remaining { color: var(--text); }
#practice-word .error { color: var(--danger); }

#practice-progress {
  margin-top: 16px; height: 6px;
  background: var(--surface2); border-radius: 3px; overflow: hidden;
}
#practice-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--success), var(--accent));
  border-radius: 3px;
  transition: width .1s;
  width: 0%;
}

#practice-input-wrap { position: relative; }
#practice-input {
  width: 100%; padding: 16px 20px;
  background: var(--surface2); border: 2px solid var(--surface2);
  border-radius: var(--radius); color: var(--text);
  font-size: 1.3rem; letter-spacing: 3px; outline: none;
  font-family: 'Courier New', monospace; text-align: center;
  transition: border-color .15s;
}
#practice-input:focus { border-color: var(--accent); }
#practice-input.correct { border-color: var(--success); }
#practice-input.wrong   { border-color: var(--danger); }

#practice-stats {
  display: flex; justify-content: center; gap: 32px;
  font-size: .9rem; color: var(--text-dim);
}
#practice-stats strong { color: var(--accent); }

/* ── Responsive ───────────────────────────────────── */
@media (max-width: 480px) {
  .logo h1 { font-size: 2.2rem; }
  .diff-buttons { flex-direction: column; }
  .final-stats { grid-template-columns: 1fr; }
  #practice-word { font-size: 2rem; }
}