:root {
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --accent: #c7a35d; /* Elegant Gold */
    --accent-dark: #a6854d;
    --bg-dark: #0f172a;
    --bg-light: #f8fafc;
    --white: #ffffff;
    --error: #e53e3e;
    --marker: rgba(199, 163, 93, 0.2);
    --shadow-soft: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-heavy: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

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

body {
    background-color: var(--white);
    color: var(--text-primary);
    font-family: 'Noto Sans JP', sans-serif;
    line-height: 1.8;
    overflow-x: hidden;
    padding-top: 80px; /* Space for sticky nav */
}

/* Sticky Nav */
.sticky-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    z-index: 1000;
    display: flex;
    align-items: center;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-weight: 700;
    color: var(--bg-dark);
    font-size: 1.2rem;
}

.nav-cta {
    background-color: var(--accent);
    color: var(--white);
    padding: 12px 24px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(199, 163, 93, 0.2);
}

.nav-cta:hover {
    background-color: var(--accent-dark);
    transform: translateY(-2px);
    box-shadow: 0 8px 12px rgba(199, 163, 93, 0.3);
}

@media (max-width: 768px) {
    .nav-logo { display: none; }
    .nav-container { justify-content: center; }
    .nav-cta { width: 100%; text-align: center; }
}

/* Typography Overdue */
h1, h2, h3 {
    line-height: 1.3;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.article-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Section Transitions */
.section {
    padding: 100px 0;
}

.section-dark {
    background-color: var(--bg-dark);
    color: var(--white);
}

.section-light {
    background-color: var(--bg-light);
}

/* Article Elements */
h2 {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    margin-bottom: 1.5em;
    position: relative;
    padding-bottom: 0.5em;
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: var(--accent);
}

h3 {
    font-size: 1.5rem;
    margin: 2em 0 1em;
    padding-left: 15px;
    border-left: 4px solid var(--accent);
}

p {
    margin-bottom: 2em;
    font-size: 1.1rem;
    color: inherit;
}

/* Specific Article Components */
.balloon {
    background: #edf2f7;
    padding: 30px;
    border-radius: 20px;
    margin: 3em 0;
    position: relative;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--text-primary);
}

.balloon::before {
    content: '“';
    position: absolute;
    top: -20px;
    left: 20px;
    font-size: 4rem;
    color: var(--accent);
    opacity: 0.3;
}

.js-marker {
    background: linear-gradient(transparent 60%, var(--marker) 60%);
    font-weight: 700;
}

.summary-box {
    background: var(--white);
    border: 2px solid var(--accent);
    padding: 40px;
    border-radius: 24px;
    margin: 3em 0;
    box-shadow: var(--shadow-soft);
}

.summary-box ul {
    list-style: none;
}

.summary-box li {
    padding-left: 30px;
    position: relative;
    margin-bottom: 15px;
}

.summary-box li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: 900;
}

.note {
    background: #fffbeb;
    border-left: 6px solid #fbbf24;
    padding: 30px;
    margin: 3em 0;
    border-radius: 0 20px 20px 0;
}

/* Interaction */
.cta-area {
    text-align: center;
    padding: 100px 20px;
    background: var(--bg-dark);
    color: var(--white);
    border-radius: 50px 50px 0 0;
    margin-top: 100px;
}

.cta-button {
    display: inline-block;
    background-color: var(--accent);
    color: var(--white);
    padding: 24px 60px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.3rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 10px 20px rgba(199, 163, 93, 0.4);
    margin-top: 30px;
}

.cta-button:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 20px 30px rgba(199, 163, 93, 0.5);
    background-color: var(--accent-dark);
}

/* Table Design */
.spec-table {
    width: 100%;
    border-collapse: collapse;
    margin: 3em 0;
    background: var(--white);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-heavy);
}

.section-image {
    width: 100%;
    max-height: 480px;
    object-fit: cover;
    border-radius: 24px;
    margin: 1em 0 3em;
    box-shadow: var(--shadow-heavy);
    display: block;
}

.spec-table th, .spec-table td {
    padding: 20px;
    border: 1px solid #e2e8f0;
    text-align: left;
}

.spec-table th {
    background: var(--bg-dark);
    color: var(--white);
}

/* Responsive */
@media (max-width: 768px) {
    h2 { font-size: 1.5rem; }
    .section { padding: 60px 0; }
    .balloon, .summary-box, .note { padding: 20px; }
}