html {
    font-size: 100%; /* 16px base font size for easier rem calculation */
}

body {
    margin: 0;
    font-family: "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: #fdfcfa;
    color: #333;
    line-height: 1.8; /* Slightly increased for better readability */
    font-weight: 400;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    background: linear-gradient(to right, #8e9eab, #eef2f3);
    color: #fff;
    padding: 60px 20px;
    text-align: center;
    border-bottom-left-radius: 50% 20%;
    border-bottom-right-radius: 50% 20%;
}

header h1 {
    font-size: 2.25rem;
    margin-bottom: 1rem;
    color: #4a5568;
    font-weight: 700;
    line-height: 1.4;
}

header p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    color: #4a5568;
}

.btn {
    background-color: #d53f8c;
    color: white;
    padding: 15px 35px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    transition: background-color 0.3s ease, transform 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    display: inline-block;
}

.btn:hover {
    background-color: #b83280;
    transform: translateY(-2px);
}

section {
    padding: 60px 20px;
}

.text-center {
    text-align: center;
}

.main-visual {
    max-width: 100%;
    height: auto;
    border-radius: 15px;
    margin-top: 40px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

.section-visual {
    max-width: 100%;
    height: auto;
    border-radius: 15px;
    margin-bottom: 40px; /* Add margin to the bottom */
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

.lead {
    font-size: 1.2rem;
}

h2 {
    text-align: center;
    font-size: 2rem;
    color: #4a5568;
    margin-bottom: 40px;
    font-weight: 700;
    line-height: 1.4;
}

.card-container {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}

.card {
    background-color: #fff;
    border-radius: 15px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
    padding: 30px;
    width: calc(33.333% - 20px);
    box-sizing: border-box;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.card h3 {
    font-size: 1.25rem;
    color: #d53f8c;
    margin-top: 0;
    font-weight: 700;
}

ul, ol {
    padding-left: 20px;
    max-width: 560px;
    margin: 0 auto;
}

li {
    margin-bottom: 10px;
}

.cta-section {
    background-color: #4a5568;
    color: #fff;
    padding: 80px 20px;
    text-align: center;
    margin-top: 40px;
}

.cta-section h2 {
    color: #fff;
}

.cta-section .btn {
    background-color: #fff;
    color: #d53f8c;
}

.cta-section .btn:hover {
    background-color: #f0f0f0;
}

footer {
    background-color: #eef2f3;
    color: #4a5568;
    text-align: center;
    padding: 40px 20px;
    font-size: 0.9rem;
}

/* --- Accordion Styles --- */
.accordion {
    max-width: 760px;
    margin: 0 auto;
}

.accordion details {
    background-color: #fff;
    border-radius: 10px;
    margin-bottom: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    border: 1px solid #eef2f3;
}

.accordion summary {
    padding: 20px;
    font-weight: 700;
    color: #4a5568;
    cursor: pointer;
    list-style: none; /* Remove default marker */
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.accordion summary::-webkit-details-marker {
    display: none; /* Hide Safari's default marker */
}

.accordion summary::after {
    content: '+';
    font-size: 1.5rem;
    color: #d53f8c;
    transition: transform 0.3s ease;
}

.accordion details[open] summary::after {
    transform: rotate(45deg);
}

.accordion-content {
    padding: 0 20px 20px;
    color: #555;
    line-height: 1.7;
}

/* --- Testimonial Styles --- */
.testimonial {
    background-color: #fdfcfa;
    border-left: 4px solid #d53f8c;
    padding: 15px 20px;
    margin-bottom: 10px;
    border-radius: 0 5px 5px 0;
}

.testimonial p {
    margin: 0;
    font-style: italic;
}

/* --- Responsive Styles --- */

@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }

    h2 {
        font-size: 1.6rem;
    }

    .card {
        width: calc(50% - 20px);
    }
}

@media (max-width: 480px) {
    html {
        font-size: 93.75%; /* 15px base */
    }

    header {
        padding: 40px 20px;
    }

    header h1 {
        font-size: 1.5rem;
    }

    h2 {
        font-size: 1.4rem;
    }

    .card {
        width: 100%;
    }

    section {
        padding: 40px 20px;
    }

    .cta-section {
        padding: 60px 20px;
    }
}