* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html,
body {
    height: 100%;
}

body {
    min-height: 100vh;
    height: 100vh;
    font-family: 'Poppins', sans-serif;
    color: var(--text);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: clamp(8px, 2vh, 24px) clamp(10px, 3vw, 20px);
    overflow: hidden;
    background:
        radial-gradient(circle at 15% 10%, rgba(139, 92, 246, 0.25), transparent 45%),
        radial-gradient(circle at 85% 85%, rgba(236, 72, 153, 0.18), transparent 45%),
        linear-gradient(160deg, var(--bg-1), var(--bg-2));
    background-attachment: fixed;
}

.container {
    width: 100%;
    max-width: 440px;
    max-height: 100%;
    background: var(--card);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-xl);
    padding: clamp(14px, 3vh, 32px) clamp(16px, 4vw, 26px);
    backdrop-filter: blur(18px);
    box-shadow: 0 30px 60px -25px rgba(0, 0, 0, 0.6);
    display: flex;
    flex-direction: column;
    gap: clamp(8px, 1.8vh, 22px);
    overflow-y: auto;
}

:root {
    --bg-1: #12101d;
    --bg-2: #1a1630;
    --card: rgba(255, 255, 255, 0.04);
    --card-border: rgba(255, 255, 255, 0.08);
    --cell: rgba(255, 255, 255, 0.03);
    --cell-hover: rgba(255, 255, 255, 0.07);

    --text: #f2f0fa;
    --text-dim: #a7a1c4;
    --text-faint: #6b6690;

    --x-color: #4fc3ff;
    --x-glow: rgba(79, 195, 255, 0.55);
    --o-color: #ff5fa8;
    --o-glow: rgba(255, 95, 168, 0.55);

    --accent-1: #8b5cf6;
    --accent-2: #ec4899;
    --win: #ffcf5c;

    --radius-xl: 26px;
    --radius-lg: 18px;
    --radius-md: 12px;
    --radius-sm: 8px;
}

h1 {
    text-align: center;
    font-weight: 600;
    font-size: clamp(1.3rem, 4vh, 1.9rem);
    letter-spacing: 0.01em;
}

h1 span {
    font-weight: 700;
    background: linear-gradient(120deg, var(--accent-1), var(--accent-2));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

/* ---------------- controls ---------------- */

.controls {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.control-box {
    display: flex;
    flex-direction: column;
    gap: 6px;
    min-width: 0;
}

.control-box label {
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-faint);
    font-weight: 500;
    padding-left: 2px;
}

.control-box select {
    appearance: none;
    -webkit-appearance: none;
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid var(--card-border);
    color: var(--text);
    font-family: 'Poppins', sans-serif;
    font-size: 0.82rem;
    font-weight: 500;
    padding: 9px 26px 9px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    background-image: linear-gradient(45deg, transparent 50%, var(--text-dim) 50%),
        linear-gradient(135deg, var(--text-dim) 50%, transparent 50%);
    background-position: calc(100% - 15px) center, calc(100% - 10px) center;
    background-size: 5px 5px, 5px 5px;
    background-repeat: no-repeat;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.control-box select:hover {
    border-color: var(--accent-1);
}

.control-box select:focus {
    outline: none;
    border-color: var(--accent-1);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.25);
}

.control-box select option {
    background: #1a1630;
    color: var(--text);
}

/* ---------------- status ---------------- */

#status {
    text-align: center;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dim);
    padding: clamp(7px, 1.4vh, 10px) 14px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    transition: color 0.2s ease;
}

#status.win {
    color: var(--win);
}

#status.draw {
    color: var(--text-dim);
}

/* ---------------- board ---------------- */

.board {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    gap: clamp(5px, 1vh, 8px);
    width: min(100%, 46vh);
    max-width: 100%;
    aspect-ratio: 1 / 1;
    margin: 0 auto;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: clamp(5px, 1vh, 8px);
}

.cell {
    background: var(--cell);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(1.4rem, 5vh, 2.6rem);
    font-weight: 700;
    cursor: pointer;
    user-select: none;
    position: relative;
    transition: background 0.18s ease, transform 0.1s ease;
}

.cell:hover {
    background: var(--cell-hover);
}

.cell:active {
    transform: scale(0.95);
}

.cell.disabled {
    cursor: default;
}

.cell.x,
.cell.o {
    animation: pop-in 0.22s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.cell.x {
    color: var(--x-color);
    text-shadow: 0 0 16px var(--x-glow);
}

.cell.o {
    color: var(--o-color);
    text-shadow: 0 0 16px var(--o-glow);
}

@keyframes pop-in {
    from {
        opacity: 0;
        transform: scale(0.4);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

.cell.win-cell {
    border-color: var(--win);
    box-shadow: 0 0 18px -2px rgba(255, 207, 92, 0.6);
    animation: win-pulse 1.1s ease-in-out infinite;
}

@keyframes win-pulse {

    0%,
    100% {
        box-shadow: 0 0 12px -2px rgba(255, 207, 92, 0.45);
    }

    50% {
        box-shadow: 0 0 22px 2px rgba(255, 207, 92, 0.75);
    }
}

/* ---------------- buttons ---------------- */

.buttons {
    display: flex;
    gap: 10px;
}

.buttons button {
    flex: 1;
    border: none;
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    font-size: 0.85rem;
    padding: clamp(9px, 1.6vh, 12px) 10px;
    border-radius: 999px;
    cursor: pointer;
    transition: transform 0.15s ease, box-shadow 0.15s ease, opacity 0.15s ease;
}

#restartBtn {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--card-border);
    color: var(--text);
}

#restartBtn:hover {
    border-color: var(--accent-1);
    color: var(--accent-1);
}

#newGameBtn {
    background: linear-gradient(120deg, var(--accent-1), var(--accent-2));
    color: #fff;
}

#newGameBtn:hover {
    box-shadow: 0 8px 20px -8px rgba(236, 72, 153, 0.6);
    transform: translateY(-1px);
}

.buttons button:active {
    transform: scale(0.97);
}

/* ---------------- scoreboard ---------------- */

.scoreboard {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
}

.score {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    padding: clamp(8px, 1.6vh, 12px) 6px;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.score h3 {
    font-size: 0.66rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--text-faint);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.score span {
    font-size: clamp(1.1rem, 3vh, 1.4rem);
    font-weight: 700;
    color: var(--text);
    transition: color 0.2s ease;
}

/* ---------------- responsive ---------------- */

@media (max-width: 420px) {
    .container {
        padding: 20px 16px;
    }

    h1 {
        font-size: 1.5rem;
    }

    .controls {
        grid-template-columns: 1fr 1fr;
    }

    .controls .control-box:nth-child(3) {
        grid-column: span 2;
    }
}

@media (max-height: 700px) {
    .container {
        gap: 8px;
    }

    .board {
        width: min(100%, 38vh);
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.001ms !important;
        transition-duration: 0.001ms !important;
    }
}