:root {
    --text-color: #333333;
    --bg-color: #f8f9fa;
    /* Very light gray, close to white */
    --line-color: #06C755;
    --line-hover: #05b34c;
    --spacing-unit: 1rem;
    --font-family: 'Noto Sans JP', sans-serif;
}

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

body {
    font-family: var(--font-family);
    color: var(--text-color);
    background-color: var(--bg-color);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    overflow: hidden;
    /* Prevent scroll on simple page */
    position: relative;
}

/* Background Effect (Subtle Gradient/Pattern could be added here if needed, keeping it clean for now) */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 50% 50%, #ffffff 0%, #f0f2f5 100%);
    z-index: -1;
}

.container {
    padding: 2rem;
    max-width: 600px;
    width: 100%;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    justify-content: center;
}

.content {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.4;
    letter-spacing: 0.05em;
    color: #1a1a1a;
}

.subtext {
    font-size: 1rem;
    color: #666;
    margin-bottom: 3rem;
    line-height: 1.8;
}

/* Button Styles */
.line-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background-color: var(--line-color);
    color: #fff;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: 50px;
    /* Pill shape */
    font-weight: 700;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(6, 199, 85, 0.3);
}

.line-button:hover {
    background-color: var(--line-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(6, 199, 85, 0.4);
}

.line-button:active {
    transform: translateY(0);
}

.line-icon {
    width: 24px;
    height: 24px;
    margin-right: 12px;
    fill: currentColor;
}

/* Footer Styles */
.footer {
    padding-top: 2rem;
    padding-bottom: 1rem;
    font-size: 0.8rem;
    color: #999;
}

/* Animations */
.fade-in {
    opacity: 0;
    animation: fadeIn 0.8s ease-out forwards;
}

.fade-in-delay {
    opacity: 0;
    animation: fadeIn 0.8s ease-out 0.3s forwards;
}

.fade-in-delay-more {
    opacity: 0;
    animation: fadeIn 0.8s ease-out 0.6s forwards;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media (max-width: 480px) {
    h1 {
        font-size: 1.5rem;
    }

    .mobile-break {
        display: block;
        /* Break line on mobile for better balance */
    }

    .subtext {
        font-size: 0.9rem;
    }

    .line-button {
        width: 100%;
        /* Full width button on mobile */
    }
}

@media (min-width: 481px) {
    .mobile-break {
        display: none;
    }
}