/* Design Guidelines Implementation */
:root {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --accent-color: #FFBF00;
    /* Amber */
    --accent-dark: #cc9900;
    --muted-color: #888;
    --border-color: #333;
    --serif-font: 'Noto Serif JP', serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--serif-font);
    line-height: 1.8;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 100px 0;
}

.dark-bg {
    background-color: #0a0a0a;
}

.center {
    text-align: center;
}

.mt-4 {
    margin-top: 40px;
}

/* Typography */
h1,
h2,
h3,
h4,
h5 {
    font-weight: 700;
    letter-spacing: 0.1em;
}

.section-title {
    font-size: 2.5rem;
    color: var(--accent-color);
    text-align: center;
    margin-bottom: 60px;
    text-transform: uppercase;
}

/* Header */
#header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 20px 0;
    transition: 0.3s;
}

#header.scrolled {
    background-color: rgba(18, 18, 18, 0.95);
    padding: 10px 0;
    border-bottom: 1px solid var(--border-color);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 40px;
}

.logo {
    font-size: 1.2rem;
    color: var(--accent-color);
}

.nav ul {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav a {
    font-size: 0.9rem;
    text-transform: uppercase;
}

.nav a:hover {
    color: var(--accent-color);
}

.btn-line-header {
    border: 1px solid var(--accent-color);
    padding: 5px 15px;
    border-radius: 20px;
}

/* Hero */
#hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.6)), url('images/hero_bg.png') no-repeat center center/cover;
}

.hero-content {
    max-width: 800px;
}

.hero-subline {
    font-size: 1rem;
    color: var(--accent-color);
    margin-bottom: 10px;
}

.hero-title {
    font-size: 3.5rem;
    line-height: 1.3;
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.2rem;
    margin-bottom: 40px;
    opacity: 0.8;
}

.btn-primary {
    display: inline-block;
    background-color: var(--accent-color);
    color: #121212;
    padding: 15px 40px;
    font-weight: 700;
    border-radius: 30px;
    box-shadow: 0 10px 20px rgba(255, 191, 0, 0.2);
}

.btn-primary:hover {
    transform: translateY(-3px);
    background-color: #ffd700;
}

/* Intro */
.intro-box {
    text-align: center;
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto;
    border-left: 1px solid var(--accent-color);
    border-right: 1px solid var(--accent-color);
    padding: 40px;
}

/* Rules */
.rules-box {
    background-color: #1a1a1a;
    padding: 60px;
    border-radius: 10px;
}

.rules-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin: 40px 0 60px;
}

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

.rule-num {
    font-size: 3rem;
    color: var(--accent-color);
    opacity: 0.3;
    display: block;
    margin-bottom: 10px;
}

.rule-item h4 {
    margin-bottom: 15px;
}

.safety-rules {
    border-top: 1px solid var(--border-color);
    padding-top: 40px;
}

.check-list li {
    margin-bottom: 10px;
    padding-left: 30px;
    position: relative;
}

.check-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-color);
}

/* Flow */
.flow-steps {
    display: flex;
    justify-content: space-between;
    gap: 20px;
}

.step {
    flex: 1;
    text-align: center;
    position: relative;
}

.step-icon {
    width: 60px;
    height: 60px;
    border: 1px solid var(--accent-color);
    color: var(--accent-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 1.5rem;
}

/* Style & System */
.system-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.fee-list li {
    display: flex;
    justify-content: space-between;
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
}

.fee-list li span:last-child {
    font-weight: 700;
    color: var(--accent-color);
}

/* FAQ */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--border-color);
    padding: 20px 0;
}

.faq-q {
    font-weight: 700;
    cursor: pointer;
    padding-right: 30px;
    position: relative;
}

.faq-q::after {
    content: '+';
    position: absolute;
    right: 0;
    color: var(--accent-color);
}

.faq-a {
    margin-top: 15px;
    display: none;
    color: var(--muted-color);
}

.faq-item.active .faq-a {
    display: block;
}

.faq-item.active .faq-q::after {
    content: '-';
}

/* Contact Templates */
.template-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 40px;
}

.template-box {
    background-color: #1a1a1a;
    padding: 20px;
    border-radius: 5px;
}

.template-box h5 {
    color: var(--accent-color);
    margin-bottom: 15px;
}

pre {
    font-family: inherit;
    font-size: 0.8rem;
    white-space: pre-wrap;
    background: #000;
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 15px;
}

.btn-copy {
    background: transparent;
    color: var(--accent-color);
    border: 1px solid var(--accent-color);
    padding: 5px 15px;
    cursor: pointer;
    font-size: 0.8rem;
}

/* Footer */
#footer {
    padding: 60px 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.8rem;
    color: var(--muted-color);
}

.footer-links {
    margin-top: 20px;
}

.footer-links a {
    margin: 0 10px;
}

/* Responsive */
@media (max-width: 768px) {
    .header-inner {
        flex-direction: column;
        gap: 15px;
    }

    .nav ul {
        gap: 15px;
    }

    .hero-title {
        font-size: 2rem;
    }

    .rules-grid,
    .flow-steps,
    .system-grid,
    .template-grid {
        grid-template-columns: 1fr;
    }

    .section {
        padding: 60px 0;
    }
}