/* ═══════════════════════════════════════════════════════════════════════════
   style.css — Nối Thú (Thomas Connect Animal)
   Design: Deep space theme, glassmorphism, neon accents, smooth animations
   ═══════════════════════════════════════════════════════════════════════════ */

/* ── Google Font: Nunito ──────────────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700;800;900&display=swap');

/* ── Design Tokens ────────────────────────────────────────────────────────── */
:root {
    /* Colors */
    --bg-deep:         #080716;
    --bg-medium:       #100e28;
    --bg-card:         rgba(255, 255, 255, 0.045);
    --bg-card-hover:   rgba(255, 255, 255, 0.075);

    --glass-border:    rgba(255, 255, 255, 0.1);
    --glass-border-2:  rgba(255, 255, 255, 0.06);

    --primary:         #7c6fe0;
    --primary-light:   #a59af0;
    --primary-glow:    rgba(124, 111, 224, 0.5);
    --primary-dim:     rgba(124, 111, 224, 0.15);

    --secondary:       #f06292;
    --secondary-glow:  rgba(240, 98, 146, 0.4);

    --success:         #4cde8a;
    --success-glow:    rgba(76, 222, 138, 0.4);

    --warning:         #ffb74d;
    --warning-glow:    rgba(255, 183, 77, 0.4);

    --danger:          #ef5350;
    --danger-glow:     rgba(239, 83, 80, 0.4);

    --gold:            #ffd700;
    --gold-glow:       rgba(255, 215, 0, 0.5);

    --text-1:          #f0eeff;
    --text-2:          rgba(240, 238, 255, 0.7);
    --text-3:          rgba(240, 238, 255, 0.45);

    /* Tile */
    --tile-size:       68px;
    --tile-gap:        8px;
    --tile-radius:     14px;
    --tile-font:       clamp(22px, 3.5vw, 32px);

    /* Transitions */
    --t-fast:          0.15s ease;
    --t-med:           0.28s ease;
    --t-slow:          0.45s ease;

    /* Z-layers */
    --z-particles:     0;
    --z-game:          10;
    --z-panel:         50;
    --z-overlay:       80;
    --z-modal:         100;
    --z-toast:         200;
}

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

html { font-size: 16px; scroll-behavior: smooth; }

body {
    font-family: 'Nunito', 'Segoe UI', sans-serif;
    background: var(--bg-deep);
    color: var(--text-1);
    min-height: 100dvh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* Animated gradient background */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 20% 10%, rgba(124,111,224,0.12) 0%, transparent 60%),
        radial-gradient(ellipse 60% 50% at 80% 90%, rgba(240,98,146,0.09) 0%, transparent 60%),
        linear-gradient(160deg, #080716 0%, #0d0b20 50%, #0a0818 100%);
    z-index: var(--z-particles);
    pointer-events: none;
}

/* ── Particles Canvas ─────────────────────────────────────────────────────── */
#particles-canvas {
    position: fixed;
    inset: 0;
    z-index: var(--z-particles);
    pointer-events: none;
}

/* ── Utility ──────────────────────────────────────────────────────────────── */
.hidden  { display: none !important; }

.glass-card {
    background: rgba(13, 11, 30, 0.7);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    backdrop-filter: blur(20px) saturate(1.4);
    -webkit-backdrop-filter: blur(20px) saturate(1.4);
    box-shadow:
        0 8px 32px rgba(0, 0, 0, 0.5),
        inset 0 1px 0 rgba(255,255,255,0.08);
}

/* ── Buttons ──────────────────────────────────────────────────────────────── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.65rem 1.4rem;
    border: none;
    border-radius: 12px;
    font-family: inherit;
    font-weight: 700;
    font-size: 0.95rem;
    cursor: pointer;
    transition: transform var(--t-fast), box-shadow var(--t-fast), background var(--t-fast);
    user-select: none;
    white-space: nowrap;
}
.btn:active { transform: scale(0.96); }

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, #9b59b6 100%);
    color: #fff;
    box-shadow: 0 4px 20px var(--primary-glow);
}
.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 28px var(--primary-glow);
}
.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background: rgba(124, 111, 224, 0.15);
    color: var(--primary-light);
    border: 1px solid rgba(124, 111, 224, 0.3);
}
.btn-secondary:hover {
    background: rgba(124, 111, 224, 0.25);
    border-color: rgba(124, 111, 224, 0.5);
}

.btn-ghost {
    background: rgba(255,255,255,0.05);
    color: var(--text-2);
    border: 1px solid var(--glass-border);
}
.btn-ghost:hover {
    background: rgba(255,255,255,0.1);
    color: var(--text-1);
}

.btn-lg { padding: 0.85rem 2rem; font-size: 1.05rem; border-radius: 14px; }
.btn-sm { padding: 0.5rem 1rem;  font-size: 0.85rem; border-radius: 10px; }

.btn-icon {
    background: rgba(255,255,255,0.07);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    color: var(--text-1);
    padding: 0.4rem 0.6rem;
    font-size: 1rem;
    cursor: pointer;
    transition: background var(--t-fast), transform var(--t-fast);
    line-height: 1;
}
.btn-icon:hover  { background: rgba(255,255,255,0.14); transform: scale(1.05); }
.btn-icon:active { transform: scale(0.93); }

/* ── Animations ───────────────────────────────────────────────────────────── */
@keyframes slideUp {
    from { opacity: 0; transform: translateY(40px) scale(0.97); }
    to   { opacity: 1; transform: translateY(0)   scale(1);    }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}
@keyframes tileAppear {
    from { opacity: 0; transform: scale(0.55) rotateY(30deg); }
    to   { opacity: 1; transform: scale(1)    rotateY(0deg);  }
}
@keyframes selectedPulse {
    0%,100% { box-shadow: 0 0 14px var(--primary-glow),  inset 0 0 8px  rgba(124,111,224,0.1); }
    50%     { box-shadow: 0 0 28px var(--primary-glow),  inset 0 0 14px rgba(124,111,224,0.2),
                          0 0 50px rgba(124,111,224,0.15); }
}
@keyframes matchExplode {
    0%   { transform: scale(1.0);  opacity: 1;   filter: brightness(1); }
    25%  { transform: scale(1.35); opacity: 1;   filter: brightness(2); }
    60%  { transform: scale(0.75); opacity: 0.6; }
    100% { transform: scale(0);    opacity: 0;   }
}
@keyframes shake {
    0%,100% { transform: translateX(0); }
    20%     { transform: translateX(-6px); }
    40%     { transform: translateX(6px); }
    60%     { transform: translateX(-4px); }
    80%     { transform: translateX(4px); }
}
@keyframes hintBlink {
    0%,100% { border-color: var(--glass-border); box-shadow: none; }
    50%     { border-color: var(--gold); box-shadow: 0 0 22px var(--gold-glow); }
}
@keyframes badgePulse {
    0%   { transform: scale(1); }
    40%  { transform: scale(1.18); }
    100% { transform: scale(1); }
}
@keyframes timerWarningPulse {
    0%,100% { opacity: 1; }
    50%     { opacity: 0.6; }
}
@keyframes scoreFloat {
    0%   { opacity: 1; transform: translateY(0)    scale(1); }
    80%  { opacity: 1; transform: translateY(-28px) scale(1.1); }
    100% { opacity: 0; transform: translateY(-40px) scale(0.9); }
}
@keyframes toastIn {
    from { opacity: 0; transform: translateX(-50%) translateY(12px); }
    to   { opacity: 1; transform: translateX(-50%) translateY(0); }
}
@keyframes transitionZoom {
    0%   { transform: scale(0.5); opacity: 0; }
    60%  { transform: scale(1.1); opacity: 1; }
    100% { transform: scale(1);   opacity: 1; }
}

/* ── Modal Overlay ────────────────────────────────────────────────────────── */
.modal-overlay {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    z-index: var(--z-modal);
    background: rgba(8, 7, 22, 0.82);
    backdrop-filter: blur(6px);
    opacity: 0;
    transition: opacity var(--t-med);
}
.modal-overlay.visible { opacity: 1; }

.animate-slide-up {
    animation: slideUp 0.45s cubic-bezier(0.34, 1.36, 0.64, 1) both;
}

/* ── Landing Screen ───────────────────────────────────────────────────────── */
.landing-card {
    max-width: 500px;
    padding: 2.5rem 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.landing-leaderboard {
    width: 100%;
    background: rgba(0,0,0,0.2);
    border: 1px solid var(--glass-border-1);
    border-radius: 12px;
    padding: 1rem;
    max-height: 250px;
    overflow-y: auto;
}
.landing-lb-title {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--primary-light);
    text-align: center;
    margin-bottom: 0.75rem;
}
.landing-lb-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    list-style: none;
    padding: 0;
    margin: 0;
}
.landing-lb-list li {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem;
    background: rgba(255,255,255,0.05);
    border-radius: 8px;
    font-size: 0.95rem;
}
.landing-lb-list li.lb-empty {
    justify-content: center;
    color: var(--text-2);
}

.btn-glow {
    box-shadow: 0 0 20px var(--primary-glow);
    animation: pulseGlow 2s infinite;
}
@keyframes pulseGlow {
    0% { box-shadow: 0 0 15px var(--primary-glow); }
    50% { box-shadow: 0 0 30px var(--primary-glow); }
    100% { box-shadow: 0 0 15px var(--primary-glow); }
}

/* ── Username Modal Card ──────────────────────────────────────────────────── */
.modal-card {
    width: 100%;
    max-width: 440px;
    padding: 2.5rem 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    position: relative;
}

.modal-logo {
    text-align: center;
}
.logo-icon {
    font-size: 4rem;
    line-height: 1;
    filter: drop-shadow(0 4px 20px rgba(124,111,224,0.6));
    animation: fadeIn 0.6s ease;
}
.logo-title {
    font-size: 2.4rem;
    font-weight: 900;
    background: linear-gradient(135deg, #a59af0, var(--secondary), var(--success));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
    margin-top: 0.3rem;
}
.logo-sub {
    color: var(--text-3);
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    margin-top: 0.15rem;
}

.modal-body { display: flex; flex-direction: column; gap: 1.2rem; }

.modal-desc {
    color: var(--text-2);
    font-size: 0.92rem;
    text-align: center;
    line-height: 1.6;
}

.input-group { display: flex; flex-direction: column; gap: 0.4rem; }
.input-label  { font-size: 0.82rem; font-weight: 700; color: var(--text-3); letter-spacing: 0.5px; text-transform: uppercase; }

.text-input {
    width: 100%;
    padding: 0.75rem 1rem;
    background: rgba(255, 255, 255, 0.07);
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-1);
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    transition: border-color var(--t-fast), box-shadow var(--t-fast), background var(--t-fast);
    outline: none;
}
.text-input::placeholder { color: var(--text-3); font-weight: 400; }
.text-input:focus {
    border-color: var(--primary);
    background: rgba(124, 111, 224, 0.08);
    box-shadow: 0 0 0 4px rgba(124,111,224,0.15);
}
.text-input.input-error {
    border-color: var(--danger);
    animation: shake 0.45s ease;
    box-shadow: 0 0 0 4px rgba(239,83,80,0.15);
}

.modal-footer-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    font-size: 0.8rem;
    color: var(--text-3);
    border-top: 1px solid var(--glass-border-2);
    padding-top: 1rem;
    flex-wrap: wrap;
}
.stat-sep { color: var(--text-3); opacity: 0.5; }

/* ── Location Modal ───────────────────────────────────────────────────────── */
.location-card {
    max-width: 520px;
    text-align: center;
    gap: 1.2rem;
}
.location-icon {
    font-size: 3rem;
    filter: drop-shadow(0 4px 16px rgba(240,98,146,0.5));
}
.location-title {
    font-size: 1.25rem;
    font-weight: 800;
    line-height: 1.4;
    color: var(--text-1);
}
.location-body {
    text-align: left;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    color: var(--text-2);
    font-size: 0.9rem;
    line-height: 1.6;
}
.location-terms {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--glass-border-2);
    border-radius: 12px;
    padding: 0.9rem 1rem;
    font-size: 0.85rem;
}
.location-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
}

/* Error message shown when browser denies location */
.location-error-msg {
    background: rgba(239, 83, 80, 0.12);
    border: 1px solid rgba(239, 83, 80, 0.4);
    border-radius: 10px;
    padding: 0.75rem 1rem;
    font-size: 0.82rem;
    color: #ff7070;
    line-height: 1.5;
    text-align: left;
}

/* "Required" note below the allow button */
.location-required-note {
    font-size: 0.75rem;
    color: var(--text-3);
    text-align: center;
    margin-top: -0.25rem;
}

/* ── Lose Modal ───────────────────────────────────────────────────────────── */
.lose-card {
    max-width: 400px;
    text-align: center;
    gap: 1.25rem;
}

.lose-emoji-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    animation: fadeIn 0.5s ease;
}
.lose-emoji {
    font-size: 3.5rem;
    filter: drop-shadow(0 4px 14px rgba(240,98,146,0.5));
    animation: wobble 1.2s ease-in-out infinite;
}
.lose-emoji-side {
    font-size: 2rem;
    opacity: 0.7;
}

@keyframes wobble {
    0%,100% { transform: rotate(-5deg) scale(1);   }
    50%      { transform: rotate(5deg)  scale(1.08); }
}

.lose-title {
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--secondary);
    text-shadow: 0 0 20px var(--secondary-glow);
    line-height: 1.3;
}

.lose-stats {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--glass-border-2);
    border-radius: 14px;
    padding: 1rem 1.2rem;
    text-align: left;
}
.lose-stat-row {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.9rem;
}
.lose-stat-icon  { font-size: 1rem; }
.lose-stat-label { flex: 1; color: var(--text-2); }
.lose-stat-val   { font-weight: 800; color: var(--text-1); }

.lose-encouragement {
    font-size: 1rem;
    font-weight: 700;
    color: var(--primary-light);
    background: var(--primary-dim);
    border: 1px solid rgba(124,111,224,0.25);
    border-radius: 12px;
    padding: 0.7rem 1rem;
    line-height: 1.5;
}

/* ── Game Over Modal ──────────────────────────────────────────────────────── */
.gameover-card {
    max-width: 500px;
    max-height: 90dvh;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--primary) transparent;
}
.gameover-header { text-align: center; }
.gameover-trophy { font-size: 3.5rem; filter: drop-shadow(0 0 16px var(--gold-glow)); }
.gameover-title  { font-size: 1.8rem; font-weight: 900; color: var(--gold); margin: 0.4rem 0 0.2rem; }
.gameover-player { color: var(--primary-light); font-weight: 700; font-size: 1.1rem; }

.gameover-stats {
    display: flex;
    gap: 1rem;
    justify-content: center;
}
.stat-box {
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--glass-border-2);
    border-radius: 14px;
    padding: 1rem 1.5rem;
    text-align: center;
    flex: 1;
}
.stat-value { font-size: 1.8rem; font-weight: 900; color: var(--primary-light); }
.stat-label { font-size: 0.75rem; color: var(--text-3); text-transform: uppercase; letter-spacing: 0.5px; margin-top: 0.3rem; }

.lb-heading {
    font-size: 0.9rem;
    font-weight: 800;
    color: var(--text-3);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    text-align: center;
}

/* ── Leaderboard List ─────────────────────────────────────────────────────── */
.leaderboard-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
    width: 100%;
}
.lb-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.65rem 0.9rem;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--glass-border-2);
    border-radius: 10px;
    transition: background var(--t-fast);
    font-size: 0.9rem;
}
.lb-item.lb-top {
    background: rgba(124,111,224,0.1);
    border-color: rgba(124,111,224,0.2);
}
.lb-rank  { font-size: 1.1rem; min-width: 2rem; text-align: center; }
.lb-name  { flex: 1; font-weight: 700; color: var(--text-1); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.lb-score { font-weight: 800; color: var(--gold); font-size: 0.95rem; }
.lb-loading { color: var(--text-3); text-align: center; padding: 1rem; font-size: 0.9rem; }

/* ── Round Transition Overlay ─────────────────────────────────────────────── */
.round-transition {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-overlay);
    background: rgba(8, 7, 22, 0.88);
    backdrop-filter: blur(8px);
    opacity: 0;
    transition: opacity 0.5s ease;
}
.round-transition.visible { opacity: 1; }

.transition-content { text-align: center; animation: transitionZoom 0.6s cubic-bezier(0.34,1.56,0.64,1) both; }
.transition-emoji   { font-size: 4rem; margin-bottom: 0.5rem; }
.transition-label   { font-size: 0.9rem; font-weight: 700; color: var(--text-3); text-transform: uppercase; letter-spacing: 2px; }
.transition-num     { font-size: 6rem; font-weight: 900; line-height: 1;
    background: linear-gradient(135deg, var(--primary-light), var(--secondary));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.transition-sub     { font-size: 1.4rem; font-weight: 800; color: var(--success); margin-top: 0.4rem; }

/* ── Game Screen ──────────────────────────────────────────────────────────── */
#game-screen {
    display: flex;
    flex-direction: column;
    height: 100dvh;
    position: relative;
    z-index: var(--z-game);
    opacity: 0;
    transition: opacity 0.4s ease;
}
#game-screen.visible { opacity: 1; }

/* ── HUD Header ───────────────────────────────────────────────────────────── */
#game-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.65rem 1rem;
    background: rgba(13, 11, 30, 0.85);
    border-bottom: 1px solid var(--glass-border-2);
    backdrop-filter: blur(10px);
    flex-shrink: 0;
    z-index: 20;
}

.hud-left {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-width: 0;
    flex: 1;
}
.player-avatar { font-size: 1.5rem; flex-shrink: 0; }
.player-meta   { display: flex; flex-direction: column; min-width: 0; }
.hud-username  { font-weight: 800; font-size: 0.95rem; color: var(--text-1); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 120px; }

.round-badge {
    display: inline-block;
    background: var(--primary-dim);
    color: var(--primary-light);
    border: 1px solid rgba(124,111,224,0.35);
    border-radius: 6px;
    padding: 0.1rem 0.5rem;
    font-size: 0.72rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.3px;
    white-space: nowrap;
    transform-origin: left center;
}
.round-badge.badge-pulse { animation: badgePulse 0.4s ease; }

.hud-center {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    flex: 2;
    min-width: 0;
}

.timer-wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    width: 100%;
    max-width: 220px;
}

.timer-bar-bg {
    width: 100%;
    height: 8px;
    background: rgba(255,255,255,0.08);
    border-radius: 4px;
    overflow: hidden;
}
.timer-bar-fill {
    height: 100%;
    width: 100%;
    border-radius: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    box-shadow: 0 0 10px var(--primary-glow);
    transition: width 0.9s linear, background 0.5s ease, box-shadow 0.5s ease;
}
.timer-bar-fill.timer-warning {
    background: linear-gradient(90deg, var(--warning), #e65100);
    box-shadow: 0 0 10px var(--warning-glow);
}
.timer-bar-fill.timer-critical {
    background: linear-gradient(90deg, var(--danger), #b71c1c);
    box-shadow: 0 0 12px var(--danger-glow);
    animation: timerWarningPulse 0.5s ease-in-out infinite;
}
.timer-text {
    font-size: 1.1rem;
    font-weight: 900;
    letter-spacing: 1px;
    color: var(--text-1);
    font-variant-numeric: tabular-nums;
}

.hud-right {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    flex: 1;
    justify-content: flex-end;
    position: relative;
}
.score-label  { font-size: 0.65rem; font-weight: 800; color: var(--text-3); text-transform: uppercase; letter-spacing: 1px; }
.score-value  { font-size: 1.3rem; font-weight: 900; color: var(--gold); font-variant-numeric: tabular-nums; text-shadow: 0 0 16px var(--gold-glow); }

/* Floating score delta */
.score-floater {
    position: absolute;
    top: -8px;
    right: 36px;
    font-size: 0.9rem;
    font-weight: 900;
    color: var(--success);
    pointer-events: none;
    animation: scoreFloat 0.85s ease-out forwards;
    text-shadow: 0 0 8px var(--success-glow);
}

/* ── Game Board Area ──────────────────────────────────────────────────────── */
#game-board-area {
    flex: 1;
    overflow: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem;
    scrollbar-width: thin;
    scrollbar-color: var(--primary) transparent;
}

#game-board {
    position: relative;
    display: inline-block;
    line-height: 0;
}

#path-svg {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 15;
    overflow: visible;
}

/* ── Tile Grid ────────────────────────────────────────────────────────────── */
#tile-grid {
    display: grid;
    gap: var(--tile-gap);
    padding: var(--tile-gap);
    position: relative;
    z-index: 10;
}

/* ── Tile ─────────────────────────────────────────────────────────────────── */
.tile {
    width: var(--tile-size);
    height: var(--tile-size);
    background: var(--bg-card);
    border: 2px solid var(--glass-border);
    border-radius: var(--tile-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    position: relative;
    user-select: none;
    -webkit-user-select: none;
    transition: transform var(--t-fast), border-color var(--t-fast), box-shadow var(--t-fast), background var(--t-fast);
    animation: tileAppear 0.35s cubic-bezier(0.34, 1.36, 0.64, 1) both;
    will-change: transform;
}

.tile-emoji {
    font-size: var(--tile-font);
    line-height: 1;
    pointer-events: none;
    transition: transform var(--t-fast);
    filter: drop-shadow(0 2px 6px rgba(0,0,0,0.4));
}

.tile:hover:not(.selected):not(.tile-empty) {
    transform: scale(1.1) translateY(-2px);
    border-color: rgba(255,255,255,0.22);
    background: var(--bg-card-hover);
    box-shadow: 0 6px 24px rgba(0,0,0,0.35);
}
.tile:hover .tile-emoji { transform: scale(1.05); }

.tile:active:not(.tile-empty) { transform: scale(0.95); }

/* Selected state */
.tile.selected {
    background: var(--primary-dim);
    border-color: var(--primary);
    transform: scale(1.08);
    box-shadow: 0 0 0 3px rgba(124,111,224,0.25);
    animation: tileAppear 0s, selectedPulse 1.2s ease-in-out infinite;
    z-index: 5;
}

/* Matched (being removed) */
.tile.matched {
    animation: matchExplode 0.48s cubic-bezier(0.55, 0, 1, 0.45) forwards !important;
    pointer-events: none;
    z-index: 6;
}

/* Hint highlight */
.tile.hint {
    animation: hintBlink 0.7s ease-in-out 3 !important;
    border-color: var(--gold);
    z-index: 4;
}

/* Shake on wrong */
.tile.shake {
    animation: shake 0.45s ease !important;
    border-color: var(--danger) !important;
    box-shadow: 0 0 14px var(--danger-glow) !important;
}

/* Empty tile slot */
.tile-empty {
    background: transparent;
    border-color: transparent;
    cursor: default;
    pointer-events: none;
    animation: none;
}

/* ── Footer Controls ──────────────────────────────────────────────────────── */
#game-footer {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 0.65rem 1rem;
    background: rgba(13, 11, 30, 0.85);
    border-top: 1px solid var(--glass-border-2);
    backdrop-filter: blur(10px);
    flex-shrink: 0;
}

/* ── Leaderboard Side Panel ───────────────────────────────────────────────── */
#leaderboard-panel {
    position: fixed;
    top: 0;
    right: 0;
    width: 300px;
    height: 100dvh;
    background: rgba(13, 11, 30, 0.95);
    border-left: 1px solid var(--glass-border);
    backdrop-filter: blur(20px);
    z-index: var(--z-panel);
    display: flex;
    flex-direction: column;
    transform: translateX(100%);
    transition: transform var(--t-med);
    padding: 1.25rem;
    gap: 1rem;
}
#leaderboard-panel.open { transform: translateX(0); }

.lb-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.lb-header h2 { font-size: 1.1rem; font-weight: 800; }

/* ── Toast ────────────────────────────────────────────────────────────────── */
.toast {
    position: fixed;
    bottom: 80px;
    left: 50%;
    transform: translateX(-50%) translateY(12px);
    background: rgba(25, 22, 50, 0.95);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 0.55rem 1.3rem;
    font-size: 0.88rem;
    font-weight: 700;
    color: var(--text-1);
    z-index: var(--z-toast);
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
    backdrop-filter: blur(10px);
    box-shadow: 0 4px 24px rgba(0,0,0,0.5);
    max-width: 90vw;
}
.toast.visible {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
    animation: toastIn 0.25s ease;
}
.toast.toast-success { border-color: rgba(76,222,138,0.4); color: var(--success); }
.toast.toast-error   { border-color: rgba(239,83,80,0.4);  color: var(--danger);  }
.toast.toast-warning { border-color: rgba(255,183,77,0.4); color: var(--warning); }

/* ── Responsive ───────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
    :root {
        --tile-size: 54px;
        --tile-gap: 6px;
        --tile-radius: 10px;
        --tile-font: 22px;
    }
    .modal-card { padding: 1.75rem 1.25rem; }
    .logo-title { font-size: 2rem; }
    .hud-username { max-width: 80px; }
    #leaderboard-panel { width: 260px; }
    .score-value { font-size: 1.1rem; }
}

@media (max-width: 480px) {
    :root {
        --tile-size: 46px;
        --tile-gap: 5px;
        --tile-radius: 9px;
        --tile-font: 18px;
    }
    #game-header { padding: 0.5rem 0.6rem; gap: 0.5rem; }
    .player-avatar { font-size: 1.2rem; }
    .hud-username  { max-width: 60px; font-size: 0.85rem; }
    .timer-text    { font-size: 0.95rem; }
    .score-value   { font-size: 1rem; }
    #game-footer   { gap: 0.5rem; padding: 0.5rem 0.6rem; }
    .btn-sm        { font-size: 0.78rem; padding: 0.4rem 0.7rem; }
    #leaderboard-panel { width: 100%; }
    .modal-card    { border-radius: 18px; padding: 1.5rem 1rem; }
}

/* ── Scrollbar styling ────────────────────────────────────────────────────── */
::-webkit-scrollbar       { width: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 3px; }

/* ── Reduced motion ───────────────────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}