:root {
    --white: #f2f2f2;      
    --green: #6b6b6b;    
    --dark-white: #b0b0b0;  
    --dark-black: #1c1c1c;
    /* horror */
    --glow: 255, 110, 0;                 
    --blood: 160, 10, 10;
}

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

body{
    width: 100%;
    height: 100vh;
    max-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--white);
    transition: all 1s ease;
}

body.dark{
    background: var(--dark-black);
}

/* mode button */
.mode{
    position: absolute;
    top: 10px;
    right: 10px;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
    outline: none;
    background: var(--green);
    color: var(--white);
    border-radius: 10px;
    cursor: pointer;
    z-index: 1000;
    transition: all 1s ease, color 1s ease 0.5s;
}

body.dark .mode{
    background: var(--dark-white);
    color: var(--dark-black);
}

/* board section */
.con{
    border: 5px solid var(--green);
    border-radius: 10px;
    overflow: hidden;
    transition: all 1s ease;
}

body.dark .con{
    border-color: var(--dark-white);
}

.board{
    display: grid;
    grid-template-columns: repeat(8,  auto);
    align-items: center;
    justify-content: center;
    width: 500px;
    height: 500px;
    z-index: 100;
}

.square{
    width: calc(500px / 8);
    height: calc(500px / 8);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 1s ease;
    cursor: pointer;
    position: relative;
}

.square img{
    width: 70%;
    filter: drop-shadow(0px 0px 5px var(--green));
    object-fit: contain;
    user-select: none;
    -webkit-user-drag: none;
    transition: all 1s ease;
}

body.dark .square img{
    filter: drop-shadow(0px 0px 5px var(--dark-black));
}

.square.light{
    background: var(--white);
}

body.dark .square.light{
    background: var(--dark-white);
}

.square.dark{
    background: var(--green);
}

body.dark .square.dark{
    background: var(--dark-black);
}

/* game section */
.place{
    width: 50%;
    height: 50%;
    border-radius: 50px;
    background: rgba(0, 0, 0, 0.2);
    position: absolute;
}
/* check */
.king-check{
    box-shadow: inset 0px 0px 10px 10px rgba(220, 70, 70, 0.7);
}

/* promotion */
.pro{
    display: flex;
    align-items: center;
    justify-content: center;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    opacity: 0;
    transition: all 1s ease;
}

.pro.show{
    pointer-events: all;
    opacity: 1;
}

.proCon{
    width: 400px;
    height: 400px;
    display: grid;
    grid-template-columns: repeat(2, auto);
    gap: 10px;
}

.proCon button{
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
    border: none;
    outline: none;
    cursor: pointer;
    background: var(--green);
    box-shadow: 0px 0px 10px 5px var(--dark-black);
    transition: all 1s ease;
}

body.dark .proCon button{
    background: var(--dark-black);
    box-shadow: 0px 0px 10px 5px var(--dark-white);
}

.proCon button img{
    width: 80%;
    filter: drop-shadow(0px 0px 5px var(--dark-black));
    transition: all 1s ease;
}

body.dark .proCon button img{
    filter: drop-shadow(0px 0px 5px var(--dark-white));
}

.proCon button:hover img{
    scale: 1.05;
}

.gameOver {
    position: fixed;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
}

.gameOver.show {
    display: flex;
}

.gameOverBox {
    background: white;
    padding: 50px;
    border-radius: 15px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 20px;
}

.gameOverBox h2 {
    margin-bottom: 10px;
}

.gameOverBox button {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
}

/* horror */
.pumpkin{
    position: fixed;
    bottom: 0;
    left: 0;
    width: 200px;      
    aspect-ratio: 1 / 1;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;                
    user-select: none;
    translate: 0 24%;
    animation: peek 10s ease-in-out infinite;
    z-index: 2;
}

.pumpkin::before{
    content: "";
    position: absolute;
    inset: -50% -45% -20% -45%;
    z-index: 0;
    background: radial-gradient(circle at 35% 75%, rgba(var(--glow), 0.30), transparent 55%), radial-gradient(circle at 70% 90%, rgba(var(--blood), 0.35), transparent 60%);
    filter: blur(18px);
    animation: fog 7s ease-in-out infinite alternate;
}

.pumpkin::after{
    content: "";
    position: absolute;
    inset: -80% -60% 0 -80%;
    z-index: 0;
    background: radial-gradient(circle at 0% 100%, rgba(0, 0, 0, 0.75), transparent 65%);
}

.pumpkin .Hcon{
    position: relative;
    z-index: 1;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    transform-origin: 20% 100%;           
    animation: sway 6s ease-in-out infinite alternate, lurch 11s linear infinite;
}

.pumpkin .Hcon img{
    width: 100%;
    height: 100%;
    object-fit: contain;
    -webkit-user-drag: none;
    filter: drop-shadow(0 0 10px rgba(var(--glow), 0.8)) drop-shadow(0 0 28px rgba(var(--blood), 0.55)) brightness(1);
    animation: candle 3.4s ease-in-out infinite;
}

@keyframes peek{
    0%{ 
        translate: 0 25%; 
    }
    55%{ 
        translate: 0 5%; 
    }
    100%{ 
        translate: 0 25%; 
    }
}

@keyframes sway{
    from{ 
        rotate: -3deg; 
    }
    to{ 
        rotate: 3deg; 
    }
}

@keyframes lurch{
    0%, 90%, 100%{ 
        scale: 1; 
        translate: 0 0; 
    }
    92%{ 
        scale: 1.12; 
        translate: 4% -6%; 
    }
    93%{ 
        scale: 1.06; 
        translate: -3% -3%; 
    }
    95%{ 
        scale: 1.14; 
        translate: 3% -7%; 
    }
    97%{ 
        scale: 1; 
        translate: 0 0; 
    }
}

@keyframes candle{
    0%{   
        filter: drop-shadow(0 0 10px rgba(var(--glow), 0.8)) drop-shadow(0 0 28px rgba(var(--blood), 0.55)) brightness(1); 
    }
    7%{   
        filter: drop-shadow(0 0 4px  rgba(var(--glow), 0.35)) drop-shadow(0 0 14px rgba(var(--blood), 0.3)) brightness(0.7); 
    }
    11%{  
        filter: drop-shadow(0 0 14px rgba(var(--glow), 0.95)) drop-shadow(0 0 34px rgba(var(--blood), 0.6)) brightness(1.2); 
    }
    19%{  
        filter: drop-shadow(0 0 8px  rgba(var(--glow), 0.6)) drop-shadow(0 0 22px rgba(var(--blood), 0.45)) brightness(0.9); 
    }
    23%{  
        filter: drop-shadow(0 0 3px  rgba(var(--glow), 0.25)) drop-shadow(0 0 10px rgba(var(--blood), 0.2)) brightness(0.55); 
    }
    26%{  
        filter: drop-shadow(0 0 12px rgba(var(--glow), 0.9)) drop-shadow(0 0 30px rgba(var(--blood), 0.55)) brightness(1.1); 
    }
    58%{  
        filter: drop-shadow(0 0 9px  rgba(var(--glow), 0.7)) drop-shadow(0 0 26px rgba(var(--blood), 0.5)) brightness(0.95); 
    }
    63%{  
        filter: drop-shadow(0 0 5px  rgba(var(--glow), 0.4)) drop-shadow(0 0 16px rgba(var(--blood), 0.3)) brightness(0.75); 
    }
    67%{  
        filter: drop-shadow(0 0 13px rgba(var(--glow), 0.9)) drop-shadow(0 0 32px rgba(var(--blood), 0.6)) brightness(1.15); 
    }
}

@keyframes fog{
    from{ 
        opacity: 0.55; 
        transform: translateX(-5%) scale(1); 
    }
    to{   
        opacity: 1;    
        transform: translateX(5%)  
        scale(1.2); 
    }
}

.ghost{
    position: fixed;
    width: 100%;
    height: 100%;
    z-index: 110;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
}

.ghost .Gcon{
    position: absolute;
    top: 0;
    left: 0;
    width: 200px;
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: moving 50s ease-in-out infinite, size 50S ease-in-out infinite;
    opacity: 0.5;
    will-change: transform;
}

.ghost .Gcon img{
    width: 100%;
    height: 100%;
    object-fit: contain;
    animation: rotation 5s ease-in-out infinite;
}

@keyframes moving {
    0%{ transform: translate( calc((100vw - 200px) * 0.10), calc((100vh - 200px) * 0.20)) }
    15%{ transform: translate( calc((100vw - 200px) * 0.75), calc((100vh - 200px) * 0.06)) }
    30%{ transform: translate( calc((100vw - 200px) * 0.92), calc((100vh - 200px) * 0.60)) }
    45%{ transform: translate( calc((100vw - 200px) * 0.45), calc((100vh - 200px) * 0.92)) }
    60%{ transform: translate( calc((100vw - 200px) * 0.05), calc((100vh - 200px) * 0.65)) }
    75%{ transform: translate( calc((100vw - 200px) * 0.30), calc((100vh - 200px) * 0.25)) }
    90%{ transform: translate( calc((100vw - 200px) * 0.62), calc((100vh - 200px) * 0.50)) }
    100%{ transform: translate( calc((100vw - 200px) * 0.10), calc((100vh - 200px) * 0.20)) }
}

@keyframes size {
    0%{ scale: 1; }
    15%{ scale: 1.05; }
    30%{ scale: 0.95; }
    45%{ scale: 1.2; }
    60%{ scale: 1.25; }
    75%{ scale: 1; }
    90%{ scale: 0.95; }
    100%{ scale: 1; }
}

@keyframes rotation {
    0%{ rotate: 5deg; }
    50%{ rotate: -5deg; }
    100%{ rotate: 5deg; }
}

/* start display */
.start{
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    background: var(--dark-black);
    transition: all 0.5s ease;
    opacity: 1;
}

body.play .start{
    opacity: 0;
    pointer-events: none;
}

.start button{
    position: relative;
    padding: 15px;
    border: 1px solid var(--white);
    border-radius: 1000px;
    background: transparent;
    color: var(--white);
    font-size: 25px;
    font-family: sans-serif;
    text-transform: uppercase;
    min-width: 200px;
    cursor: pointer;
    overflow: hidden;
    transition: all 0.5s ease;
}

.start button::before{
    content: '';
    position: absolute;
    inset: 0;
    background: var(--white);
    transform: translateY(101%);
    z-index: -1;
    transition: all 0.5s ease;
}

.start button:hover{
    color: var(--dark-black);
    box-shadow: 0 10px 40px rgba(255, 255, 255, 0.12);
}

.start button:hover::before{
    transform: translateY(0);
}

.start button:active{
    scale: 0.95;
}