/* リセットCSS */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.7;
    color: #1f2937;
    /* gray-800 */
    background: #f8fafc;
    /* gray-50 */
    min-height: 100vh;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    margin-bottom: 40px;
    color: #111827;
    /* gray-900 */
}

header h1 {
    font-size: 2.25rem;
    margin-bottom: 8px;
}

header p {
    font-size: 1.05rem;
    opacity: 0.9;
}

main {
    flex: 1;
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    align-items: start;
}

.calculator {
    background: white;
    padding: 24px;
    border-radius: 16px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.input-group {
    margin-bottom: 25px;
    position: relative;
}

.input-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
}

.input-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid #e5e7eb;
    /* gray-200 */
    border-radius: 10px;
    font-size: 1rem;
    transition: all 0.2s ease;
    background: white;
}

.input-group input:focus {
    outline: none;
    border-color: #6366f1;
    /* indigo-500 */
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

.currency,
.unit {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #666;
    font-weight: 500;
    pointer-events: none;
}

.input-group input {
    padding-right: 50px;
}

#calculate-btn,
button {
    padding: 12px 16px;
    background: #111827;
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s ease, transform 0.05s ease;
}

#calculate-btn:hover,
button:hover {
    background: #0f172a;
}

#calculate-btn:active,
button:active {
    transform: translateY(1px);
}

.result {
    background: #f3f4f6;
    /* gray-100 */
    padding: 16px;
    border-radius: 12px;
    border-left: 4px solid #6366f1;
}

.result.hidden {
    display: none;
}

.result h3 {
    margin-bottom: 15px;
    color: #333;
    font-size: 1.3rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    padding: 10px 0;
    border-bottom: 1px solid #e1e5e9;
}

.result-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
}

.label {
    font-weight: 500;
    color: #666;
}

.amount {
    font-weight: 700;
    font-size: 1.2rem;
    color: #667eea;
}

.features {
    background: white;
    padding: 24px;
    border-radius: 16px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.features h3 {
    margin-bottom: 20px;
    color: #333;
    font-size: 1.5rem;
}

.features ul {
    list-style: none;
}

.features li {
    padding: 10px 0;
    font-size: 1.1rem;
    color: #555;
    border-bottom: 1px solid #f0f0f0;
}

.features li:last-child {
    border-bottom: none;
}

footer {
    text-align: center;
    margin-top: 40px;
    color: #6b7280;
    /* gray-500 */
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }

    header h1 {
        font-size: 2.5rem;
    }

    main {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .calculator,
    .features {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 2rem;
    }

    header p {
        font-size: 1rem;
    }

    .calculator,
    .features {
        padding: 15px;
    }

    .input-group input {
        padding: 12px;
        font-size: 1rem;
    }

    #calculate-btn {
        padding: 12px;
        font-size: 1.1rem;
    }
}

/* ブログ専用スタイル - モダンデザイン */
.blog-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 32px 24px;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    min-height: 100vh;
    position: relative;
}

.blog-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(circle at 20% 80%, rgba(102, 126, 234, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(118, 75, 162, 0.03) 0%, transparent 50%);
    pointer-events: none;
}

.blog-header {
    text-align: center;
    margin-bottom: 64px;
    padding: 48px 32px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    box-shadow:
        0 10px 30px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.blog-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-title {
    font-size: 3.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 24px;
    line-height: 1.1;
    letter-spacing: -0.02em;
    position: relative;
}

.blog-description {
    font-size: 1.25rem;
    color: #4a5568;
    line-height: 1.7;
    max-width: 700px;
    margin: 0 auto;
    font-weight: 400;
    opacity: 0.9;
}

.blog-categories {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin: 32px 0;
    justify-content: center;
}

.blog-category-link {
    display: inline-block;
    padding: 12px 24px;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(255, 255, 255, 0.7) 100%);
    backdrop-filter: blur(10px);
    color: #4a5568;
    text-decoration: none;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    position: relative;
    overflow: hidden;
}


.blog-category-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
    background: linear-gradient(135deg, rgba(255, 255, 255, 1) 0%, rgba(255, 255, 255, 0.9) 100%);
}

.blog-posts-list {
    list-style: none;
    padding: 0;
    margin: 0;
    position: relative;
    z-index: 1;
}

.blog-post-item {
    margin-bottom: 40px;
    position: relative;
}

.blog-post-card {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 16px;
    padding: 32px;
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow:
        0 8px 25px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}

.blog-post-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-post-card:hover {
    transform: translateY(-4px);
    box-shadow:
        0 15px 35px rgba(0, 0, 0, 0.12),
        0 0 0 1px rgba(255, 255, 255, 0.3);
    background: rgba(255, 255, 255, 0.98);
}

.blog-post-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: #2d3748;
    margin: 0 0 16px 0;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.blog-post-title a {
    color: inherit;
    text-decoration: none;
    transition: all 0.3s ease;
    position: relative;
}

.blog-post-title a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    transition: width 0.3s ease;
}

.blog-post-title a:hover::after {
    width: 100%;
}

.blog-post-title a:hover {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.blog-post-meta {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 20px;
    font-size: 0.9rem;
    color: #718096;
    font-weight: 500;
}

.blog-post-date {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-radius: 20px;
    border: 1px solid rgba(102, 126, 234, 0.2);
}

.blog-post-reading-time {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: linear-gradient(135deg, rgba(240, 147, 251, 0.1) 0%, rgba(245, 87, 108, 0.1) 100%);
    border-radius: 20px;
    border: 1px solid rgba(240, 147, 251, 0.2);
}

.blog-post-excerpt {
    color: #4a5568;
    line-height: 1.8;
    margin-bottom: 24px;
    font-size: 1.1rem;
    font-weight: 400;
}

.blog-post-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 24px;
}

.blog-tag {
    display: inline-block;
    padding: 8px 16px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    color: #667eea;
    border-radius: 25px;
    font-size: 0.8rem;
    font-weight: 600;
    border: 1px solid rgba(102, 126, 234, 0.2);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}


.blog-tag:hover {
    transform: translateY(-1px);
    box-shadow: 0 3px 10px rgba(102, 126, 234, 0.2);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.15) 0%, rgba(118, 75, 162, 0.15) 100%);
}

.blog-read-more {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    padding: 12px 24px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-radius: 25px;
    border: 1px solid rgba(102, 126, 234, 0.2);
    position: relative;
    overflow: hidden;
}


.blog-read-more:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.15) 0%, rgba(118, 75, 162, 0.15) 100%);
    gap: 12px;
}

.blog-navigation {
    margin-bottom: 32px;
    position: relative;
    z-index: 1;
}

.blog-nav-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 600;
    transition: all 0.3s ease;
    padding: 12px 20px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 25px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}


.blog-nav-link:hover {
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    background: rgba(255, 255, 255, 0.2);
}

.blog-article {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 48px;
    box-shadow:
        0 15px 35px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.blog-article::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-article-header {
    margin-bottom: 48px;
    padding-bottom: 32px;
    border-bottom: 2px solid rgba(102, 126, 234, 0.1);
    position: relative;
}

.blog-article-title {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 0 0 24px 0;
    line-height: 1.1;
    letter-spacing: -0.02em;
}

.blog-article-meta {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 24px;
    font-size: 0.95rem;
    color: #718096;
    font-weight: 500;
}

.blog-article-content {
    line-height: 1.9;
    color: #2d3748;
    font-size: 1.125rem;
    font-weight: 400;
}

.blog-article-content h2 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 48px 0 24px 0;
    padding-bottom: 12px;
    border-bottom: 3px solid rgba(102, 126, 234, 0.2);
    position: relative;
}

.blog-article-content h2::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    border-radius: 2px;
}

.blog-article-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #4a5568;
    margin: 32px 0 16px 0;
    position: relative;
    padding-left: 20px;
}

.blog-article-content h3::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 20px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 2px;
}

.blog-article-content p {
    margin-bottom: 20px;
    text-align: justify;
}

.blog-article-content ul,
.blog-article-content ol {
    margin: 24px 0;
    padding-left: 32px;
}

.blog-article-content li {
    margin-bottom: 12px;
    line-height: 1.8;
}

.blog-author-card {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border: 2px solid rgba(102, 126, 234, 0.1);
    border-radius: 20px;
    padding: 32px;
    margin: 48px 0;
    position: relative;
    overflow: hidden;
}

.blog-author-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-author-title {
    font-weight: 700;
    color: #2d3748;
    margin-bottom: 16px;
    font-size: 1.25rem;
}

.blog-author-info {
    font-size: 1rem;
    color: #4a5568;
    line-height: 1.7;
}

.blog-author-name {
    font-weight: 700;
    color: #667eea;
}

.blog-related-posts {
    margin-top: 48px;
    padding-top: 32px;
    border-top: 2px solid rgba(102, 126, 234, 0.1);
    position: relative;
}

.blog-related-posts::before {
    content: '';
    position: absolute;
    top: -2px;
    left: 0;
    width: 60px;
    height: 2px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-related-title {
    font-weight: 700;
    color: #2d3748;
    margin-bottom: 24px;
    font-size: 1.5rem;
}

.blog-related-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.blog-related-item {
    margin-bottom: 16px;
    padding: 16px 20px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: 12px;
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.blog-related-item:hover {
    transform: translateX(4px);
    box-shadow: 0 3px 10px rgba(102, 126, 234, 0.15);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.08) 0%, rgba(118, 75, 162, 0.08) 100%);
}

.blog-related-item a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.blog-related-item a:hover {
    color: #764ba2;
}

.blog-category-header {
    text-align: center;
    margin-bottom: 48px;
    padding: 48px 32px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    box-shadow:
        0 10px 30px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.blog-category-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.blog-category-title {
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 12px;
    line-height: 1.1;
    letter-spacing: -0.02em;
}

.blog-category-count {
    color: #718096;
    font-size: 1.1rem;
    font-weight: 500;
    padding: 8px 16px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-radius: 20px;
    border: 1px solid rgba(102, 126, 234, 0.2);
    display: inline-block;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .blog-container {
        padding: 20px 16px;
    }

    .blog-header {
        padding: 32px 24px;
        margin-bottom: 48px;
    }

    .blog-title {
        font-size: 2.5rem;
    }

    .blog-article {
        padding: 32px 24px;
    }

    .blog-article-title {
        font-size: 2.25rem;
    }

    .blog-post-card {
        padding: 24px 20px;
    }

    .blog-post-title {
        font-size: 1.5rem;
    }

    .blog-categories {
        justify-content: flex-start;
        gap: 12px;
    }

    .blog-category-header {
        padding: 32px 24px;
    }

    .blog-category-title {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .blog-container {
        padding: 16px 12px;
    }

    .blog-header {
        padding: 24px 20px;
        margin-bottom: 32px;
    }

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

    .blog-description {
        font-size: 1.1rem;
    }

    .blog-article {
        padding: 24px 20px;
    }

    .blog-article-title {
        font-size: 1.75rem;
    }

    .blog-post-card {
        padding: 20px 16px;
    }

    .blog-post-title {
        font-size: 1.25rem;
    }

    .blog-post-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .blog-category-header {
        padding: 24px 20px;
    }

    .blog-category-title {
        font-size: 1.75rem;
    }

    .blog-categories {
        gap: 10px;
    }

    .blog-category-link {
        padding: 10px 20px;
        font-size: 0.85rem;
    }
}