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

body {
    background-color: #0a0a0a;
    color: #ffffff;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center; 
    height: 100vh; 
    height: 100dvh; 
    overflow: hidden;
    padding: 20px;
}

#particleCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1; 
}

.bento-grid {
    position: relative; 
    z-index: 1;         
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    max-width: 800px;
    width: 100%;
}

.card {
    background-color: #16161a;
    border-radius: 24px;
    padding: 24px;
    border: 1px solid #222227;
    transition: transform 0.25s ease, background-color 0.25s ease, border-color 0.25s ease;
}

.card:hover {
    transform: translateY(-5px);
    background-color: #1c1c22;
    border-color: #2d2d35;
}

.header-card {
    grid-column: span 2;
    display: flex;
    align-items: center;
    gap: 20px;
}

.info h1 {
    font-size: 26px;
    margin-bottom: 8px;
    font-weight: 600;
}

.info p {
    color: #a0a0ab;
    font-size: 15px;
    line-height: 1.6;
}

.btn-back {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background-color: #222227;
    border: 1px solid #2d2d35;
    color: #a0a0ab;
    font-size: 20px;
    text-decoration: none;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.btn-back:hover {
    background-color: #ffffff;
    color: #16161a;
    transform: scale(1.05);
}

.section-title {
    grid-column: span 2;
    font-size: 22px;
    font-weight: 600;
    color: #ffffff;
    margin-top: 15px;
    margin-bottom: -5px; 
    padding-bottom: 15px;
    border-bottom: 1px solid #222227;
}

.device-card h2 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #e4e4e7;
    font-weight: 600;
}

.device-card p {
    color: #a0a0ab;
    font-size: 14px;
    line-height: 1.5;
}

.pc-card {
    grid-column: span 2;
}

@media (max-width: 650px) {
    .bento-grid {
        grid-template-columns: 1fr; 
        gap: 12px;
    }
    
    .header-card, .section-title, .pc-card {
        grid-column: span 1; 
    }
    
    .card {
        padding: 14px 16px; 
    }

    .header-card {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }

    .btn-back {
        width: 42px;
        height: 42px;
        font-size: 18px;
    }

    .info h1 {
        font-size: 20px;
        margin-bottom: 2px;
    }

    .info p {
        font-size: 12px;
        line-height: 1.3;
    }

    .section-title {
        font-size: 16px;
        margin-top: 5px;
        margin-bottom: -5px; 
        padding-bottom: 10px;
    }

    .device-card h2 {
        font-size: 15px;
        margin-bottom: 4px;
    }

    .device-card p {
        font-size: 12px;
        line-height: 1.3;
    }
}