/* Global Settings */
:root {
    --primary-color: #0F172A;
    /* Dark Navy (Reference Header) */
    --accent-color: #F97316;
    /* Bright Orange (Reference CTA) */
    --text-color: #334155;
    /* Slate 700 */
    --bg-gradient-start: #EFF6FF;
    /* Light Blue */
    --bg-gradient-end: #DBEAFE;
    /* Slightly Darker Blue */
    --white: #FFFFFF;
    --font-main: 'Noto Sans JP', sans-serif;
    --max-width: 800px;
    /* Narrower for single column card look */
}

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

body {
    font-family: var(--font-main);
    background: linear-gradient(180deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
    min-height: 100vh;
    color: var(--text-color);
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
    padding-bottom: 60px;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s;
}

/* Utilities */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

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

.mt-20 {
    margin-top: 20px;
}

.mt-40 {
    margin-top: 40px;
}

.mb-20 {
    margin-bottom: 20px;
}

.mb-40 {
    margin-bottom: 40px;
}

.font-bold {
    font-weight: 700;
}

/* Components */
.btn {
    display: inline-block;
    padding: 18px 50px;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 700;
    text-align: center;
    cursor: pointer;
    box-shadow: 0 10px 15px -3px rgba(249, 115, 22, 0.3);
    transition: transform 0.2s, box-shadow 0.2s;
    letter-spacing: 0.05em;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 20px -3px rgba(249, 115, 22, 0.4);
}

.btn:active {
    transform: translateY(1px);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-color), #EA580C);
    color: var(--white);
    width: 100%;
    max-width: 400px;
}

/* Header/Hero */
.hero {
    background: transparent;
    padding: 40px 0;
    text-align: center;
}

.logo-area {
    background: var(--primary-color);
    color: var(--white);
    padding: 10px 0;
    text-align: center;
    font-size: 0.9rem;
    font-weight: bold;
    margin-bottom: 30px;
}

.hero h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 20px;
    line-height: 1.6;
    background: var(--white);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    display: inline-block;
    width: 100%;
    font-weight: 700;
}

.hero p {
    font-size: 1.0rem;
    color: #475569;
}

.hero-image-container {
    margin: 30px auto;
    max-width: 280px;
    position: relative;
    margin-left: auto;
    margin-right: auto;
}

.hero-image {
    width: 100%;
    height: auto;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.15), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    border-radius: 2px;
    transform: rotate(0deg);
    transition: transform 0.3s;
}

/* Card Style Sections */
.section {
    margin-bottom: 40px;
}

.card {
    background: var(--white);
    padding: 40px 30px;
    border-radius: 16px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    margin-bottom: 30px;
}

.section-title {
    font-size: 1.4rem;
    color: var(--primary-color);
    text-align: center;
    margin-bottom: 30px;
    position: relative;
    padding-bottom: 15px;
    border-bottom: 2px solid #E2E8F0;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 2px;
    background-color: var(--accent-color);
}

/* Content Lists */
.check-list {
    list-style: none;
}

.check-list li {
    position: relative;
    padding-left: 30px;
    margin-bottom: 15px;
    font-weight: 700;
    color: var(--text-color);
    border-bottom: 1px dashed #e2e8f0;
    padding-bottom: 15px;
}

.check-list li::before {
    content: '✔';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: bold;
    font-size: 1.2rem;
}

.chapter-list {
    list-style: none;
    text-align: left;
}

.chapter-list li {
    margin-bottom: 20px;
}

.chapter-title {
    font-weight: 700;
    color: var(--primary-color);
    display: block;
    margin-bottom: 5px;
    font-size: 1.1rem;
}

.chapter-desc {
    font-size: 0.9rem;
    color: #64748B;
    padding-left: 1em;
}

/* Footer */
footer {
    text-align: center;
    font-size: 0.85rem;
    color: #64748B;
    margin-top: 60px;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }

    .hero h1 {
        font-size: 1.3rem;
        padding: 20px;
    }

    .card {
        padding: 30px 20px;
    }

    .btn {
        width: 100%;
        padding: 15px 20px;
        font-size: 1.1rem;
    }
}