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

/* Global Styles */
body {
    font-family: 'Open Sans', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

/* Header */
header {
    background: #fff;
    padding: 1rem 2rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 100;
}
.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: #333;
}

/* Hero Section */
.hero {
    position: relative;
    background: url('images/hero-background.jpg') no-repeat center center/cover;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 60px; /* for fixed header */
}
.hero-overlay {
    background-color: rgba(255, 255, 255, 0.85); /* 背景透明度調整済み */
    padding: 2.5rem 2rem;
    border-radius: 12px;
    max-width: 800px;
    width: 90%;
    margin: 0 auto;
}
.hero h1 {
    font-size: 2.2rem; /* 調整後のサイズ */
    margin-bottom: 1rem;
    color: #222;
}
.hero p {
    font-size: 1.15rem;
    margin-bottom: 1.5rem;
    color: #555;
    line-height: 1.5;
}

/* Pre-Registration Section */
.pre-registration {
    background-color: #fffbf5; /* 柔らかいアイボリー */
    padding: 2rem 1rem;
    margin: 2rem auto;
    max-width: 1000px;
    border-radius: 10px;
    text-align: center;
}
.pre-registration h2 {
    font-size: 2rem;
    margin-bottom: 0.75rem;
    color: #333;
}
.pre-registration p {
    font-size: 1.1rem;
    margin-bottom: 1.25rem;
    color: #555;
}
#registration-form {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 0.5rem;
}
#registration-form input[type="email"] {
    padding: 0.8rem;
    width: 70%;
    max-width: 300px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 1rem;
}
#registration-form button {
    padding: 0.8rem 1.2rem;
    background: #ff6f91;
    color: #fff;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.3s;
}
#registration-form button:hover {
    background: #e55b7e;
}

/* Sections */
section {
    padding: 3rem 1rem;
    max-width: 1000px;
    margin: 4rem auto;
    border-radius: 10px;
}

/* Features Section */
.features {
    background-color: #f0f8ff; /* AliceBlue */
}
.features h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 2rem;
    color: #333;
}
.feature-item {
    margin-bottom: 1.5rem;
}
.feature-item h3 {
    font-size: 1.6rem;
    margin-bottom: 0.5rem;
    color: #222;
}
.feature-item p {
    font-size: 1.1rem;
    color: #555;
    line-height: 1.5;
}

/* Science Section */
.science {
    background-color: #fffaf0; /* FloralWhite */
    text-align: justify;
}
.science h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 2rem;
    color: #333;
}
.science p {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 1.25rem;
    line-height: 1.6;
}
.evidence {
    font-size: 0.9rem;
    color: #0073e6;
    text-align: center;
    margin-top: 1rem;
}
.evidence a {
    color: #0073e6;
    text-decoration: underline;
}
.evidence a:hover {
    color: #005bb5;
}

/* Usage Section */
.usage {
    background-color: #f8f8ff; /* GhostWhite */
    text-align: justify;
}
.usage h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 2rem;
    color: #333;
}
.usage p {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}
.usage img {
    display: block;
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
    border-radius: 8px;
}

/* FAQ Section */
.faq {
    background-color: #f0f8ff; /* AliceBlue */
}
.faq h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 2rem;
    color: #333;
}
.faq-item {
    margin-bottom: 1.5rem;
}
.faq-item h3 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
    color: #222;
}
.faq-item p {
    font-size: 1rem;
    color: #555;
    line-height: 1.5;
}

/* CTA Section */
.cta {
    background-color: #fffaf0; /* FloralWhite */
    text-align: center;
    padding: 2.5rem 1rem;
}
.cta h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #222;
}
.cta p {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 1.5rem;
}
#registration-form-cta {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 1rem;
}
#registration-form-cta input[type="email"] {
    padding: 0.8rem;
    width: 70%;
    max-width: 300px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 1rem;
}
#registration-form-cta button {
    padding: 0.8rem 1.2rem;
    background: #ff6f91;
    color: #fff;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.3s;
}
#registration-form-cta button:hover {
    background: #e55b7e;
}

/* Footer */
footer {
    background: #fff;
    text-align: center;
    padding: 1rem;
    font-size: 0.9rem;
    color: #777;
}
  
/* Modal Popup Styles */
.modal {
    display: none; /* 初期状態は非表示 */
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.5); /* 背景の半透明黒 */
}

.modal-content {
    background-color: #fff;
    margin: 15% auto;
    padding: 2rem;
    border: 1px solid #888;
    width: 90%;
    max-width: 500px;
    text-align: center;
    border-radius: 8px;
}

.close {
    color: #aaa;
    float: right;
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
}

.close:hover,
.close:focus {
    color: #000;
    text-decoration: none;
}

/* フッター内のSNSリンク用スタイル */
footer .social-links {
    margin-top: 1rem;
    text-align: center;
  }
  
  footer .social-links a {
    margin: 0 0.5rem;
    display: inline-block;
  }
  
  footer .social-icon {
    width: 32px; /* アイコンのサイズを適宜調整 */
    height: 32px;
    transition: opacity 0.3s;
  }
  
  footer .social-icon:hover {
    opacity: 0.8;
  }