@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Press+Start+2P&display=swap');

:root {
    color-scheme: dark;
    --bg-overlay: rgba(26, 26, 62, 0.6);
    --panel: rgba(45, 45, 94, 0.85);
    --panel-strong: rgba(30, 30, 70, 0.9);
    --border: rgba(255, 255, 255, 0.15);
    --text: #e8e8f0;
    --muted: rgba(232, 232, 240, 0.7);
    --accent: #7b9fff;
    --accent-strong: #5d7fff;
    --hot: #c77dff;
    --success: #5ff5b7;
    --sky-blue: #4a6bff;
    --sky-purple: #6b5b8a;
    --cloud-white: #d0d0e0;
    --shadow-soft: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.4);
}

*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
}

body {
    height: 100vh;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: url('assets/sky.jpg') center/cover no-repeat fixed;
    background-color: #1a1a3e;
    color: var(--text);
    overflow: hidden;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-overlay);
    z-index: 0;
    pointer-events: none;
}

button {
    font: inherit;
    border: none;
    background: none;
    color: inherit;
    cursor: pointer;
    font-family: 'Inter', sans-serif;
}

.orb {
    display: none;
}

.neon-stage {
    position: relative;
    z-index: 1;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: clamp(0.6rem, 1.5vw, 1rem);
    padding: clamp(0.8rem, 2vw, 1.2rem);
}

.game-title {
    font-family: 'Press Start 2P', monospace;
    font-size: clamp(1.2rem, 4vw, 1.8rem);
    color: var(--text);
    text-align: center;
    margin-bottom: 0.5rem;
    text-shadow: 0 0 20px rgba(123, 159, 255, 0.5), 0 0 40px rgba(199, 125, 255, 0.3), 2px 2px 4px rgba(0, 0, 0, 0.5);
    letter-spacing: 0.1em;
}

.difficulty-bar {
    display: inline-flex;
    gap: 0.5rem;
    padding: 0.4rem;
    border-radius: 16px;
    background: rgba(45, 45, 94, 0.7);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-soft);
    backdrop-filter: blur(20px);
}

.diff-btn {
    padding: 0.5rem 1rem;
    border-radius: 12px;
    text-transform: uppercase;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    color: var(--muted);
    background: transparent;
    border: 1px solid transparent;
    transition: all 0.3s ease;
    position: relative;
}

.diff-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text);
    transform: translateY(-2px);
}

.diff-btn:active {
    transform: translateY(0);
}

.diff-btn.active {
    background: rgba(45, 45, 94, 0.9);
    color: #ffffff;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.arena {
    position: relative;
    width: min(85vw, 420px);
    display: flex;
    align-items: center;
    justify-content: center;
}

.confetti {
    position: absolute;
    top: 0;
    bottom: 0;
    width: 80px;
    pointer-events: none;
    opacity: 0;
}

.confetti::before,
.confetti::after {
    content: '';
    position: absolute;
    width: 4px;
    height: 16px;
    background: var(--accent);
    border-radius: 2px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    animation: confettiFall 1.6s linear infinite;
}

.confetti::after {
    animation-delay: 0.4s;
    width: 3px;
    height: 12px;
    background: var(--hot);
}

.confetti-left {
    left: -30px;
}

.confetti-right {
    right: -30px;
}

@keyframes confettiFall {
    0% {
        transform: translateY(-20px) rotate(0deg);
        opacity: 0;
    }
    30% {
        opacity: 1;
    }
    100% {
        transform: translateY(140px) rotate(90deg);
        opacity: 0;
    }
}

.arena.celebrating .confetti {
    opacity: 1;
}

.grid-stack {
    width: 100%;
    background: url('assets/sky.jpg') center/cover no-repeat;
    background-color: var(--panel);
    border-radius: 24px;
    border: 1px solid var(--border);
    padding: clamp(0.9rem, 2.5vw, 1.3rem);
    box-shadow: var(--shadow-soft);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.8rem;
    backdrop-filter: blur(20px);
    position: relative;
    overflow: hidden;
}

.grid-stack::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--panel);
    opacity: 0.85;
    z-index: 0;
    pointer-events: none;
    border-radius: 24px;
}

.grid-stack > * {
    position: relative;
    z-index: 1;
}

.status-row {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    align-items: center;
    justify-content: space-between;
}

.status-chip {
    flex: 1;
    min-width: 140px;
    background: rgba(255, 255, 255, 0.08);
    padding: 0.5rem 0.7rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    color: var(--muted);
    font-size: 0.75rem;
    font-weight: 500;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.status-chip:hover {
    background: rgba(255, 255, 255, 0.12);
}

.players {
    display: inline-flex;
    padding: 0.25rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: rgba(45, 45, 94, 0.6);
    gap: 0.25rem;
    backdrop-filter: blur(10px);
}

.player-toggle {
    padding: 0.4rem 0.8rem;
    border-radius: 10px;
    color: var(--muted);
    font-size: 0.7rem;
    font-weight: 600;
    background: transparent;
    border: 1px solid transparent;
    transition: all 0.3s ease;
}

.player-toggle:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text);
}

.player-toggle.active {
    background: rgba(45, 45, 94, 0.9);
    color: #ffffff;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.board-shell {
    width: 100%;
    display: flex;
    justify-content: center;
}

.board {
    width: clamp(220px, 50vw, 320px);
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: clamp(0.5rem, 1.5vw, 0.7rem);
}

.cell {
    aspect-ratio: 1 / 1;
    border-radius: 16px;
    background: var(--panel-strong);
    border: 2px solid var(--border);
    display: grid;
    place-items: center;
    font-size: clamp(1.8rem, 5vw, 2.5rem);
    font-weight: 700;
    color: transparent;
    text-shadow: 0 0 12px currentColor, 2px 2px 4px rgba(0, 0, 0, 0.5);
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    position: relative;
}

.cell:hover:not([data-disabled="true"]) {
    transform: translateY(-4px);
    background: rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow-hover);
    border-color: rgba(255, 255, 255, 0.25);
}

.cell:active:not([data-disabled="true"]) {
    transform: translateY(-2px);
}

.cell[data-value="X"] {
    color: var(--accent);
    font-family: 'Press Start 2P', monospace;
    font-size: clamp(1.4rem, 4vw, 2rem);
    text-shadow: 0 0 16px var(--accent), 2px 2px 4px rgba(0, 0, 0, 0.6), 0 0 8px rgba(123, 159, 255, 0.5);
}

.cell[data-value="O"] {
    color: var(--hot);
    font-family: 'Press Start 2P', monospace;
    font-size: clamp(1.4rem, 4vw, 2rem);
    text-shadow: 0 0 16px var(--hot), 2px 2px 4px rgba(0, 0, 0, 0.6), 0 0 8px rgba(199, 125, 255, 0.5);
}

.cell.marked {
    animation: pop 0.3s ease;
}

@keyframes pop {
    0% { transform: scale(0.8); opacity: 0.6; }
    50% { transform: scale(1.1); opacity: 1; }
    100% { transform: scale(1); }
}

.cell.win {
    background: rgba(95, 245, 183, 0.2);
    border-color: var(--success);
    box-shadow: 0 0 24px rgba(95, 245, 183, 0.5), 0 4px 16px rgba(0, 0, 0, 0.3);
    animation: winPulse 1s ease-in-out infinite;
}

@keyframes winPulse {
    0%, 100% { 
        box-shadow: 0 0 24px rgba(95, 245, 183, 0.5), 0 4px 16px rgba(0, 0, 0, 0.3);
    }
    50% { 
        box-shadow: 0 0 32px rgba(95, 245, 183, 0.7), 0 4px 20px rgba(0, 0, 0, 0.4);
    }
}

.score-row {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(3, minmax(70px, 1fr));
    gap: 0.5rem;
}

.score-card {
    background: rgba(255, 255, 255, 0.06);
    border-radius: 12px;
    padding: 0.5rem 0.6rem;
    border: 1px solid var(--border);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.score-card:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.score-card span {
    font-size: 0.6rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
    font-weight: 600;
}

.score-card strong {
    display: block;
    font-size: 1.1rem;
    margin-top: 0.15rem;
    font-weight: 700;
    font-family: 'Press Start 2P', monospace;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
}

.score-card[data-player="X"] {
    border-color: rgba(123, 159, 255, 0.4);
}

.score-card[data-player="X"]:hover {
    border-color: rgba(123, 159, 255, 0.6);
    box-shadow: 0 4px 12px rgba(123, 159, 255, 0.2);
}

.score-card[data-player="O"] {
    border-color: rgba(199, 125, 255, 0.4);
}

.score-card[data-player="O"]:hover {
    border-color: rgba(199, 125, 255, 0.6);
    box-shadow: 0 4px 12px rgba(199, 125, 255, 0.2);
}

.score-card[data-player="draw"] {
    border-color: var(--border);
}

.ghost-btn {
    width: 100%;
    padding: 0.6rem 1rem;
    border-radius: 12px;
    border: 2px solid var(--border);
    background: transparent;
    font-weight: 600;
    font-size: 0.7rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.ghost-btn:hover,
.ghost-btn:focus-visible {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.ghost-btn:active {
    transform: translateY(0);
}

.intro-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('assets/sky.jpg') center/cover no-repeat fixed;
    background-color: #1a1a3e;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 1;
    transition: opacity 0.6s ease-out, visibility 0.6s ease-out;
    visibility: visible;
    overflow: hidden;
}

.intro-screen::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        var(--bg-overlay),
        radial-gradient(circle at 20% 30%, rgba(123, 159, 255, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(199, 125, 255, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 50% 50%, rgba(95, 245, 183, 0.1) 0%, transparent 50%);
    z-index: 1;
    pointer-events: none;
    animation: floatParticles 20s ease-in-out infinite;
}

.intro-screen::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        135deg,
        rgba(123, 159, 255, 0.1) 0%,
        rgba(199, 125, 255, 0.08) 50%,
        rgba(95, 245, 183, 0.1) 100%
    );
    z-index: 2;
    pointer-events: none;
    animation: gradientShift 8s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% {
        opacity: 0.6;
        transform: scale(1);
    }
    50% {
        opacity: 0.8;
        transform: scale(1.05);
    }
}

.intro-screen.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.intro-content {
    text-align: center;
    padding: clamp(1.5rem, 4vw, 2.5rem);
    background: var(--panel);
    border-radius: 24px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-soft), 0 0 60px rgba(123, 159, 255, 0.3), 0 0 100px rgba(199, 125, 255, 0.2);
    backdrop-filter: blur(20px);
    max-width: min(90vw, 500px);
    animation: introFadeIn 0.8s ease-out;
    overflow: hidden;
    box-sizing: border-box;
    position: relative;
    z-index: 3;
}

.intro-content::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(
        circle,
        rgba(123, 159, 255, 0.15) 0%,
        rgba(199, 125, 255, 0.1) 30%,
        transparent 70%
    );
    animation: pulseGlow 4s ease-in-out infinite;
    pointer-events: none;
    z-index: -1;
}

@keyframes pulseGlow {
    0%, 100% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.1);
        opacity: 0.8;
    }
}

@keyframes introFadeIn {
    0% {
        opacity: 0;
        transform: translateY(20px) scale(0.95);
    }
    100% {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@keyframes floatParticles {
    0%, 100% {
        opacity: 0.6;
        transform: translateY(0) translateX(0) scale(1);
    }
    33% {
        opacity: 0.7;
        transform: translateY(-15px) translateX(8px) scale(1.02);
    }
    66% {
        opacity: 0.65;
        transform: translateY(8px) translateX(-8px) scale(0.98);
    }
}

.intro-title {
    font-family: 'Press Start 2P', monospace;
    font-size: clamp(1.2rem, 4vw, 2rem);
    color: var(--text);
    margin-bottom: 1rem;
    text-shadow: 0 0 20px rgba(123, 159, 255, 0.6), 0 0 40px rgba(199, 125, 255, 0.4), 2px 2px 4px rgba(0, 0, 0, 0.5);
    letter-spacing: 0.08em;
    animation: pixelGlow 2s ease-in-out infinite;
    white-space: nowrap;
    max-width: 100%;
    display: block;
    word-break: keep-all;
}

@keyframes pixelGlow {
    0%, 100% {
        text-shadow: 0 0 20px rgba(123, 159, 255, 0.6), 0 0 40px rgba(199, 125, 255, 0.4), 2px 2px 4px rgba(0, 0, 0, 0.5);
    }
    50% {
        text-shadow: 0 0 30px rgba(123, 159, 255, 0.8), 0 0 60px rgba(199, 125, 255, 0.6), 2px 2px 4px rgba(0, 0, 0, 0.5);
    }
}

.intro-subtitle {
    font-family: 'Inter', sans-serif;
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    color: var(--muted);
    margin-bottom: 2rem;
    font-weight: 500;
    letter-spacing: 0.05em;
}

.intro-start-btn {
    padding: 0.8rem 2rem;
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(45, 45, 94, 0.9) 0%, rgba(30, 30, 70, 0.95) 50%, rgba(45, 45, 94, 0.9) 100%);
    border: 2px solid rgba(255, 255, 255, 0.2);
    color: var(--text);
    font-family: 'Press Start 2P', monospace;
    font-size: clamp(0.6rem, 2vw, 0.8rem);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.intro-start-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.5s ease;
}

.intro-start-btn:hover::before {
    left: 100%;
}

.intro-start-btn:hover,
.intro-start-btn:focus-visible {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.15), 0 0 20px rgba(123, 159, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.3);
}

.intro-start-btn:active {
    transform: translateY(0);
}

@media (min-width: 601px) and (max-width: 1366px) {
    .intro-title {
        font-size: clamp(1.5rem, 3vw, 1.9rem);
        letter-spacing: 0.06em;
    }
}

@media (min-width: 1367px) {
    .intro-title {
        font-size: clamp(1.8rem, 2.5vw, 2.2rem);
        letter-spacing: 0.05em;
    }
}

@media (max-width: 600px) {
    .difficulty-bar {
        flex-wrap: wrap;
        justify-content: center;
    }

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

    .players {
        justify-content: center;
    }

    .score-row {
        grid-template-columns: repeat(3, 1fr);
    }

    .diff-btn {
        font-size: 0.6rem;
        padding: 0.4rem 0.8rem;
    }

    .player-toggle {
        font-size: 0.65rem;
        padding: 0.35rem 0.7rem;
    }

    .status-chip {
        font-size: 0.65rem;
    }

    .ghost-btn {
        font-size: 0.65rem;
    }

    .intro-content {
        padding: 1.5rem;
    }

    .intro-title {
        font-size: clamp(1.2rem, 6vw, 1.8rem);
    }

    .intro-subtitle {
        font-size: 0.85rem;
        margin-bottom: 1.5rem;
    }

    .intro-start-btn {
        padding: 0.7rem 1.5rem;
        font-size: 0.6rem;
    }
}