/* ===========================
   RESET
=========================== */

*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    -webkit-tap-highlight-color:transparent;
}

html,body{
    width:100%;
    height:100%;
    font-family:'Poppins',sans-serif;
}

body{
    display:flex;
    justify-content:center;
    align-items:center;
    overflow:hidden;
    background:linear-gradient(135deg,#5b6cff,#7f53ff,#0fd3ff);
    background-size:400% 400%;
    animation:bgMove 15s ease infinite;
}


/* ===========================
   BACKGROUND
=========================== */

.bg{
    position:fixed;
    inset:0;
    background:
    radial-gradient(circle at 20% 20%,rgba(255,255,255,.18),transparent 35%),
    radial-gradient(circle at 80% 30%,rgba(255,255,255,.12),transparent 35%),
    radial-gradient(circle at 50% 80%,rgba(255,255,255,.15),transparent 30%);
    pointer-events:none;
}


/* ===========================
   MAIN CONTAINER
=========================== */

.container{

    width:min(95%,430px);

    background:rgba(255,255,255,.15);

    backdrop-filter:blur(18px);

    border:1px solid rgba(255,255,255,.25);

    border-radius:28px;

    padding:24px;

    box-shadow:
    0 20px 45px rgba(0,0,0,.25);

    color:#fff;
}


/* ===========================
   TITLE
=========================== */

header{
    text-align:center;
}

header h1{

    font-size:2rem;

    font-weight:700;

    margin-bottom:18px;

    letter-spacing:1px;

    text-shadow:0 4px 10px rgba(0,0,0,.2);
}


/* ===========================
   GAME MODE
=========================== */

.mode-box{

    display:flex;

    gap:10px;

    margin-bottom:20px;
}

.mode{

    flex:1;

    border:none;

    cursor:pointer;

    color:#fff;

    border-radius:16px;

    background:rgba(255,255,255,.15);

    padding:13px;

    font-size:.92rem;

    transition:.25s;
}

.mode.active{

    background:#ffffff;

    color:#4b53ff;

    font-weight:600;
}

.mode:active{

    transform:scale(.95);
}


/* ===========================
   SCOREBOARD
=========================== */

.scoreboard{

    display:grid;

    grid-template-columns:repeat(3,1fr);

    gap:12px;

    margin-bottom:22px;
}

.score-card{

    background:rgba(255,255,255,.12);

    border-radius:18px;

    padding:14px;

    text-align:center;

    border:1px solid rgba(255,255,255,.18);
}

.label{

    font-size:.82rem;

    opacity:.9;
}

.score{

    margin-top:6px;

    font-size:1.7rem;

    font-weight:700;
}


/* ===========================
   DIFFICULTY
=========================== */

.difficulty{

    margin-bottom:18px;
}

.difficulty label{

    display:block;

    margin-bottom:8px;

    font-size:.88rem;
}

#difficulty{

    width:100%;

    padding:13px;

    border:none;

    outline:none;

    border-radius:14px;

    font-size:1rem;

    background:white;

    color:#333;
}


/* ===========================
   STATUS
=========================== */

.status{

    text-align:center;

    margin-bottom:20px;

    font-size:1.1rem;

    font-weight:600;

    min-height:28px;
}


/* ===========================
   BOARD
=========================== */

.board{

    position:relative;

    display:grid;

    grid-template-columns:repeat(3,1fr);

    gap:12px;

    margin-bottom:22px;
}


/* ===========================
   CELL
=========================== */

.cell{

    aspect-ratio:1;

    border-radius:20px;

    background:rgba(255,255,255,.12);

    border:2px solid rgba(255,255,255,.18);

    display:flex;

    justify-content:center;

    align-items:center;

    font-size:3rem;

    font-weight:700;

    cursor:pointer;

    transition:.25s;

    user-select:none;
}

.cell:hover{

    transform:translateY(-3px);

    background:rgba(255,255,255,.22);
}

.cell:active{

    transform:scale(.93);
}


/* X */

.cell.x{

    color:#00e8ff;

    text-shadow:
    0 0 10px #00e8ff,
    0 0 20px #00e8ff;
}


/* O */

.cell.o{

    color:#ffd84c;

    text-shadow:
    0 0 10px #ffd84c,
    0 0 20px #ffd84c;
}


/* Winning Cells */

.cell.win{

    background:#2ecc71;

    color:white;

    border-color:white;
}


/* ===========================
   BUTTONS
=========================== */

.buttons{

    display:flex;

    gap:12px;
}

.buttons button{

    flex:1;

    border:none;

    border-radius:16px;

    padding:14px;

    cursor:pointer;

    font-size:.95rem;

    font-weight:600;

    color:#fff;

    background:linear-gradient(135deg,#6f74ff,#5f2fff);

    transition:.25s;

    box-shadow:0 10px 20px rgba(0,0,0,.2);
}

.buttons button:hover{

    transform:translateY(-2px);
}

.buttons button:active{

    transform:scale(.95);
}


/* Winning Line */

.win-line{

    position:absolute;

    height:6px;

    width:0;

    background:#fff;

    border-radius:20px;

    box-shadow:0 0 12px white;

    pointer-events:none;
}


/* ===========================
   BACKGROUND ANIMATION
=========================== */

@keyframes bgMove{

0%{
background-position:0% 50%;
}

50%{
background-position:100% 50%;
}

100%{
background-position:0% 50%;
}

}



/* ==========================================
   POPUP
========================================== */

.popup{
    position:fixed;
    inset:0;
    display:flex;
    justify-content:center;
    align-items:center;
    background:rgba(0,0,0,.55);
    backdrop-filter:blur(6px);
    z-index:999;
    transition:.3s;
}

.popup.hidden{
    opacity:0;
    visibility:hidden;
}

.popup-card{
    width:min(90%,340px);
    background:rgba(255,255,255,.15);
    backdrop-filter:blur(20px);
    border:1px solid rgba(255,255,255,.25);
    border-radius:24px;
    padding:30px;
    text-align:center;
    color:#fff;
    animation:popupShow .35s ease;
    box-shadow:0 20px 40px rgba(0,0,0,.35);
}

.popup-card h2{
    margin:16px 0 24px;
    font-size:1.6rem;
}

.popup-card button{
    border:none;
    cursor:pointer;
    padding:14px 30px;
    border-radius:15px;
    font-size:1rem;
    font-weight:600;
    color:#4b53ff;
    background:#fff;
    transition:.25s;
}

.popup-card button:hover{
    transform:translateY(-2px);
}

.popup-card button:active{
    transform:scale(.95);
}

.emoji{
    font-size:4rem;
    animation:bounce 1s infinite;
}


/* ==========================================
   CELL ANIMATIONS
========================================== */

.cell.x,
.cell.o{
    animation:pop .25s ease;
}

.cell.win{
    animation:winner .9s infinite;
}


/* ==========================================
   MODE BUTTON EFFECT
========================================== */

.mode:not(.active):hover{
    background:rgba(255,255,255,.25);
}


/* ==========================================
   SCORE CARD EFFECT
========================================== */

.score-card{
    transition:.25s;
}

.score-card:hover{
    transform:translateY(-4px);
}


/* ==========================================
   STATUS EFFECT
========================================== */

.status{
    animation:fadeStatus .4s ease;
}


/* ==========================================
   CONFETTI CANVAS
========================================== */

#confetti{
    position:fixed;
    inset:0;
    width:100%;
    height:100%;
    pointer-events:none;
    z-index:998;
}


/* ==========================================
   SCROLLBAR
========================================== */

::-webkit-scrollbar{
    width:0;
}


/* ==========================================
   RESPONSIVE
========================================== */

@media (max-width:480px){

.container{
    padding:18px;
    border-radius:22px;
}

header h1{
    font-size:1.7rem;
}

.mode{
    font-size:.8rem;
    padding:12px;
}

.score{
    font-size:1.4rem;
}

.cell{
    font-size:2.6rem;
    border-radius:16px;
}

.buttons{
    flex-direction:column;
}

.buttons button{
    width:100%;
}

.popup-card{
    padding:24px;
}

.popup-card h2{
    font-size:1.35rem;
}

}


/* Small Phones */

@media (max-width:360px){

header h1{
    font-size:1.5rem;
}

.cell{
    font-size:2.2rem;
}

.mode{
    font-size:.72rem;
}

.score{
    font-size:1.2rem;
}

}


/* Tablets */

@media (min-width:700px){

.container{
    max-width:480px;
}

}


/* ==========================================
   KEYFRAMES
========================================== */

@keyframes pop{

0%{
transform:scale(.2) rotate(-20deg);
opacity:0;
}

60%{
transform:scale(1.15);
}

100%{
transform:scale(1);
opacity:1;
}

}

@keyframes popupShow{

0%{
opacity:0;
transform:scale(.7);
}

100%{
opacity:1;
transform:scale(1);
}

}

@keyframes winner{

0%{
transform:scale(1);
box-shadow:0 0 0 rgba(255,255,255,.3);
}

50%{
transform:scale(1.08);
box-shadow:0 0 25px rgba(255,255,255,.9);
}

100%{
transform:scale(1);
box-shadow:0 0 0 rgba(255,255,255,.3);
}

}

@keyframes bounce{

0%,100%{
transform:translateY(0);
}

50%{
transform:translateY(-12px);
}

}

@keyframes fadeStatus{

0%{
opacity:0;
transform:translateY(-8px);
}

100%{
opacity:1;
transform:translateY(0);
}

}


/* ==========================================
   SMOOTH FADE
========================================== */

.container,
.score-card,
.mode,
.cell,
button,
.popup-card{
    transition:
    transform .25s,
    background .25s,
    color .25s,
    box-shadow .25s,
    opacity .25s;
}