:root {
    /* Colors */
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #333333;
    --text-light: #666666;
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --border-color: #e1e4e8;

    /* Typography */
    --font-heading: 'Lato', sans-serif;
    --font-body: 'Noto Sans JP', sans-serif;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;

    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: var(--font-body);
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: var(--secondary-color);
    transition: color 0.3s ease;
}

a:hover {
    color: var(--primary-color);
}

ul {
    list-style: none;
}

/* Layout */
.container {
    width: 90%;
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

.main-wrapper {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.site-header {
    background: #fff;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
    padding: var(--spacing-sm) 0;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-color);
    letter-spacing: -0.5px;
}

.logo .subtitle {
    display: block;
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 300;
}

/* Navigation */
.main-nav ul {
    display: flex;
    gap: var(--spacing-md);
}

.main-nav a {
    color: var(--text-color);
    font-weight: 500;
    font-size: 0.95rem;
    padding: 0.5rem 0;
    position: relative;
}

.main-nav a:hover,
.main-nav a.active {
    color: var(--secondary-color);
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: width 0.3s ease;
}

.main-nav a:hover::after,
.main-nav a.active::after {
    width: 100%;
}

.language-switch a {
    background: var(--bg-color);
    color: var(--text-color);
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    border: 1px solid var(--border-color);
}

.language-switch a:hover {
    background: var(--secondary-color);
    color: #fff;
    border-color: var(--secondary-color);
}

/* Hero Section */
.hero-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-lg) 0;
    margin-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.hero-text {
    flex: 1;
}

.hero-text h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

.hero-text .intro-lead {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-xs);
}

.hero-image {
    flex: 0 0 250px;
}

.profile-img {
    width: 100%;
    border-radius: 50%;
    box-shadow: var(--shadow-md);
    border: 4px solid #fff;
}

/* Sections */
.section-card {
    background: var(--card-bg);
    border-radius: 8px;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.section-title {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--secondary-color);
    display: inline-block;
    color: var(--primary-color);
}

.section-subtitle {
    margin-top: -1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-light);
    font-size: 0.9rem;
    font-style: italic;
}

/* News List */
.news-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.news-item {
    display: flex;
    align-items: baseline;
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-color);
}

.news-item:last-child {
    border-bottom: none;
}

.news-item .date {
    flex: 0 0 120px;
    font-family: var(--font-heading);
    font-weight: 700;
    color: var(--secondary-color);
    font-size: 0.9rem;
}

/* Travel List */
.travel-list li {
    margin-bottom: var(--spacing-xs);
    display: flex;
    align-items: baseline;
}

.travel-list .date {
    display: inline-block;
    width: 100px;
    font-weight: 700;
    color: var(--text-light);
    font-size: 0.9rem;
    flex-shrink: 0;
}

/* Footer */
.site-footer {
    margin-top: auto;
    background: var(--primary-color);
    color: #fff;
    text-align: center;
    padding: var(--spacing-md) 0;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .hero-section {
        flex-direction: column-reverse;
        text-align: center;
        padding: var(--spacing-md) 0;
    }

    .hero-image {
        flex: 0 0 150px;
        width: 150px;
    }

    .main-nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: var(--spacing-sm);
    }

    .news-item {
        flex-direction: column;
        gap: 5px;
    }

    .section-card {
        padding: var(--spacing-sm);
    }

    .log-grid {
        grid-template-columns: 1fr;
    }
}

/* Travel Log Styles */
.log-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.5rem;
    /* Reduced from spacing-sm (1rem) */
    margin-top: 1rem;
}

.log-card {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    /* More subtle radius */
    overflow: hidden;
    transition: transform 0.2s, box-shadow 0.2s;
    display: flex;
    flex-direction: row;
    align-items: center;
    min-height: 50px;
    /* Reduced min-height */
}

.log-card:hover {
    transform: translateX(3px);
    box-shadow: var(--shadow-sm);
}

.log-image-container {
    width: 80px;
    /* Smaller image width */
    height: 100%;
    min-height: 60px;
    flex-shrink: 0;
    overflow: hidden;
    border-right: 1px solid var(--border-color);
    display: none;
}

.log-image-container:has(img) {
    display: block;
}

.log-image-container img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.log-content {
    padding: 0.5rem 1rem;
    /* Much tighter padding */
    flex-grow: 1;
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.log-date {
    font-size: 0.8rem;
    /* Slightly smaller */
    color: var(--secondary-color);
    font-weight: 700;
    margin-bottom: 0;
    flex: 0 0 90px;
}

.log-title {
    font-size: 0.95rem;
    /* Slightly smaller */
    font-weight: 500;
    /* Less heavy */
    margin-bottom: 0;
    color: var(--primary-color);
    margin-right: auto;
}

.log-description {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-top: 0;
}

@media (max-width: 600px) {
    .log-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.1rem;
        padding: 0.5rem;
    }

    .log-date {
        font-size: 0.75rem;
        flex: auto;
    }

    .log-title {
        font-size: 0.9rem;
    }
}

/* Research Illustration Background */
.research-bg {
    position: relative;
    padding: var(--spacing-md);
    border-radius: 8px;
    overflow: hidden;
    color: var(--text-color);
}

.research-bg::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('images/grb_illustration.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0.25; /* Adjusted transparency for visibility behind text */
    z-index: 1;
}

.research-bg > * {
    position: relative;
    z-index: 2; /* Ensure text is above the background */
}