@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700&display=swap');

:root {
    --primary-color: #007BFF;
    --secondary-color: #FFC107;
    --background-color: #f0f2f5;
    --text-color: #333;
    --white: #fff;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --glow-color: rgba(0, 123, 255, 0.5);
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-image: linear-gradient(to right, #fa709a 0%, #fee140 100%);

}

.container {
    background-color: var(--white);
    padding: 2rem 3rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px var(--shadow-color);
    text-align: center;
    width: 90%;
    max-width: 600px;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.number-container {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.number-placeholder, .number {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 600;
    background-color: #eee;
    box-shadow: 0 4px 10px var(--shadow-color);
    transition: all 0.3s ease;
}

.number {
    background-color: var(--secondary-color);
    color: var(--text-color);
    animation: pop-in 0.5s ease;
}

#generate-btn {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px var(--glow-color);
}

#generate-btn:hover, #generate-btn:focus {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--glow-color);
}

@keyframes pop-in {
    0% {
        transform: scale(0);
        opacity: 0;
    }
    60% {
        transform: scale(1.1);
        opacity: 1;
    }
    100% {
        transform: scale(1);
    }
}

@media (max-width: 600px) {
    .container {
        padding: 1.5rem;
    }

    h1 {
        font-size: 2rem;
    }

    .number-placeholder, .number {
        width: 50px;
        height: 50px;
        font-size: 1.2rem;
    }

    #generate-btn {
        padding: 0.8rem 1.5rem;
        font-size: 1rem;
    }
}