* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}
body {
    background: #f4f7f6;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    min-height: -webkit-fill-available; 
    padding: 20px;
}
.game-card {
    background: white;
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    text-align: center;
    width: 100%;
    max-width: 400px; 
    transition: transform 0.3s ease;
}
h2 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: #333;
}
.input-group {
    position: relative;
    margin: 40px 0 25px;
}
#userInput {
    width: 100%;
    padding: 12px 5px;
    font-size: 1.1rem;
    border: none;
    border-bottom: 2px solid #ccc;
    outline: none;
    background: transparent;
    transition: 0.3s;
    text-transform: uppercase;
}
.input-group label {
    position: absolute;
    top: 12px;
    left: 5px;
    color: #999;
    font-size: 1rem;
    pointer-events: none;
    transition: 0.3s ease all;
}
#userInput:focus + label,
#userInput:not(:placeholder-shown) + label {
    top: -20px;
    left: 0;
    font-size: 0.85rem;
    color: #2196F3;
    font-weight: bold;
}
#userInput:focus {
    border-bottom: 2px solid #2196F3;
}
button {
    width: 100%;
    padding: 14px;
    background: #2196F3;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.3s, transform 0.1s;
    -webkit-tap-highlight-color: transparent; 
}
button:active {
    transform: scale(0.98);
}
#displayArea {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #eee;
}
#displayArea p {
    margin: 10px 0;
    color: #555;
}
#gameResult {
    display: block;
    margin-top: 5px;
    font-size: 1.3rem;
}
.score-board {
    margin-top: 20px;
    padding: 10px;
    background: #f9f9f9;
    border-radius: 8px;
    font-size: 1rem;
    color: #333;
}

.score-board b {
    color: #2196F3;
    font-size: 1.2rem;
}
@media (max-width: 360px) {
    .game-card {
        padding: 1.5rem;
    }
    h2 {
        font-size: 1.2rem;
    }
    #userInput {
        font-size: 1rem;
    }
}
@media (min-width: 768px) {
    .game-card:hover {
        transform: translateY(-5px);
    }
}
@media (max-height: 500px) {
    body {
        align-items: flex-start;
        padding-top: 10px;
    }
    .game-card {
        padding: 1rem;
    }
}