:root {
    --paper: #f1eee6;
    --paper-bright: #fbfaf6;
    --paper-deep: #ddd7ca;
    --ink: #1d1d19;
    --ink-soft: #3e3c36;
    --muted: #6b685f;
    --line: rgba(29, 29, 25, 0.2);
    --line-light: rgba(241, 238, 230, 0.22);
    --vermilion: #b5412e;
    --vermilion-dark: #873022;
    --focus: #1f5b9b;
    --wide: 1120px;
    --article: 760px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    min-width: 320px;
    min-height: 100vh;
    margin: 0;
    overflow-x: hidden;
    background: var(--paper);
    color: var(--ink);
    font-family: "Inter", ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 16px;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

body::before {
    position: fixed;
    inset: 0;
    z-index: -1;
    background-image:
        repeating-linear-gradient(90deg, transparent 0, transparent 3px, rgba(29, 29, 25, 0.012) 4px),
        repeating-linear-gradient(0deg, transparent 0, transparent 5px, rgba(29, 29, 25, 0.01) 6px);
    content: "";
    pointer-events: none;
}

a {
    color: inherit;
    text-underline-offset: 0.18em;
}

a:focus-visible,
summary:focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 3px;
}

.column-site-header {
    display: flex;
    width: min(calc(100% - 48px), var(--wide));
    min-height: 96px;
    align-items: center;
    justify-content: space-between;
    gap: 28px;
    margin: 0 auto;
    border-bottom: 1px solid var(--line);
}

.column-wordmark {
    display: inline-flex;
    align-items: center;
    gap: 13px;
    color: var(--ink);
    text-decoration: none;
}

.column-wordmark-seal {
    display: grid;
    width: 42px;
    height: 42px;
    place-items: center;
    background: var(--vermilion);
    color: var(--paper-bright);
    font-family: "Noto Sans JP", sans-serif;
    font-size: 1.45rem;
    font-weight: 700;
    line-height: 1;
}

.column-wordmark > span:last-child {
    display: flex;
    flex-direction: column;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.08rem;
    font-weight: 700;
    line-height: 1.05;
}

.column-wordmark small {
    margin-top: 6px;
    color: var(--muted);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.66rem;
    font-weight: 650;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.column-site-header nav {
    display: flex;
    align-items: center;
    gap: 26px;
}

.column-site-header nav a {
    color: var(--ink);
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.09em;
    text-decoration: none;
    text-transform: uppercase;
}

.column-site-header nav a:first-child {
    border-bottom: 1px solid currentColor;
}

.column-tool-link {
    display: inline-flex;
    min-height: 40px;
    align-items: center;
    gap: 18px;
    padding: 0 15px;
    border: 1px solid var(--ink);
    transition: background-color 180ms ease, color 180ms ease;
}

.column-tool-link:hover {
    background: var(--ink);
    color: var(--paper) !important;
}

.column-index {
    width: min(calc(100% - 48px), var(--wide));
    margin: 0 auto;
}

.column-index-header {
    display: grid;
    align-items: end;
    gap: clamp(48px, 9vw, 130px);
    grid-template-columns: minmax(0, 1.25fr) minmax(260px, 0.75fr);
    padding: 90px 0 78px;
    border-bottom: 1px solid var(--ink);
}

.column-index-header h1 {
    margin: 0;
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(4rem, 7.4vw, 6.7rem);
    font-weight: 500;
    letter-spacing: -0.065em;
    line-height: 0.93;
}

.column-index-header h1::first-letter {
    color: var(--vermilion);
}

.column-index-header p {
    margin: 0 0 7px;
    color: var(--ink-soft);
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.12rem;
    line-height: 1.7;
}

.column-list {
    display: grid;
    gap: 42px 28px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin: 66px 0 112px;
    counter-reset: article-card;
}

.column-card {
    position: relative;
    display: flex;
    min-width: 0;
    flex-direction: column;
    border-top: 1px solid var(--ink);
    background: transparent;
    color: var(--ink);
    counter-increment: article-card;
    text-decoration: none;
}

.column-card::before {
    position: absolute;
    z-index: 2;
    top: 14px;
    left: 14px;
    display: grid;
    width: 34px;
    height: 34px;
    place-items: center;
    background: var(--paper-bright);
    color: var(--vermilion-dark);
    content: counter(article-card, decimal-leading-zero);
    font-size: 0.64rem;
    font-weight: 800;
    letter-spacing: 0.08em;
}

.column-card-image,
.article-hero-image {
    position: relative;
    overflow: hidden;
    background: var(--paper-deep);
}

.column-card-image {
    aspect-ratio: 1200 / 630;
    margin-top: 14px;
}

.column-card-image::after,
.article-hero-image::after {
    position: absolute;
    inset: 0;
    background: var(--vermilion);
    content: "";
    mix-blend-mode: multiply;
    opacity: 0.1;
    pointer-events: none;
}

.column-card-image img,
.article-hero-image img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(1) contrast(1.08);
    transition: filter 260ms ease, transform 380ms ease;
}

.column-card-body {
    display: flex;
    flex: 1;
    flex-direction: column;
    padding: 24px 4px 0;
}

.column-card-title {
    margin-bottom: 12px;
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(1.35rem, 2.4vw, 1.75rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
    transition: color 180ms ease;
}

.column-card-desc {
    flex: 1;
    color: var(--ink-soft);
    font-size: 0.86rem;
    line-height: 1.75;
}

.column-card-meta {
    margin-top: 18px;
    color: var(--muted);
    font-size: 0.66rem;
    font-weight: 800;
    letter-spacing: 0.11em;
    text-transform: uppercase;
}

@media (hover: hover) {
    .column-card:hover .column-card-title {
        color: var(--vermilion-dark);
    }

    .column-card:hover img {
        filter: grayscale(0.35) contrast(1.04);
        transform: scale(1.025);
    }
}

.column-article {
    width: min(calc(100% - 48px), var(--article));
    margin: 0 auto;
}

.article-breadcrumb {
    margin: 0 0 56px;
    padding-top: 44px;
    color: var(--muted);
    font-size: 0.68rem;
    font-weight: 750;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.article-breadcrumb a {
    color: var(--muted);
    text-decoration: none;
}

.article-breadcrumb a:hover {
    color: var(--vermilion-dark);
}

.article-breadcrumb span {
    margin: 0 9px;
    color: var(--vermilion);
}

.article-header {
    margin-bottom: 42px;
}

.article-header h1 {
    margin: 0 0 26px;
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(2.8rem, 6.2vw, 4.8rem);
    font-weight: 500;
    letter-spacing: -0.055em;
    line-height: 0.98;
}

.article-meta {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--muted);
    font-size: 0.68rem;
    font-weight: 750;
    letter-spacing: 0.09em;
    text-transform: uppercase;
}

.article-byline a {
    color: var(--ink);
    text-decoration: none;
}

.article-byline a:hover {
    color: var(--vermilion-dark);
}

.article-hero-image {
    width: 100%;
    aspect-ratio: 1200 / 630;
    margin: 0 auto 64px;
    border-top: 1px solid var(--ink);
}

.article-body {
    font-family: Georgia, "Times New Roman", serif;
}

.article-body .lead {
    margin: 0 0 58px;
    padding: 28px 0;
    border-top: 1px solid var(--ink);
    border-bottom: 1px solid var(--line);
    color: var(--ink-soft);
    font-size: clamp(1.2rem, 2.6vw, 1.42rem);
    line-height: 1.7;
}

.article-body h2 {
    margin: 68px 0 22px;
    padding-top: 18px;
    border-top: 1px solid var(--ink);
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(1.85rem, 4vw, 2.5rem);
    font-weight: 700;
    letter-spacing: -0.035em;
    line-height: 1.15;
}

.article-body h3 {
    margin: 44px 0 15px;
    color: var(--vermilion-dark);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.84rem;
    font-weight: 800;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.article-body p {
    margin: 0 0 25px;
    color: var(--ink-soft);
    font-size: 1.04rem;
    line-height: 1.9;
}

.article-body strong {
    color: var(--ink);
}

.article-body a {
    color: var(--vermilion-dark);
    font-weight: 700;
}

.key-point,
.warning-box {
    margin: 38px 0;
    padding: 26px 28px;
    border-left: 5px solid var(--vermilion);
    background: var(--paper-bright);
}

.warning-box {
    border-color: var(--ink);
    background: var(--paper-deep);
}

.key-point > strong,
.warning-box > strong {
    display: block;
    margin-bottom: 9px;
    color: var(--vermilion-dark);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.warning-box > strong {
    color: var(--ink);
}

.key-point p,
.warning-box p {
    margin: 0;
    font-size: 0.94rem;
    line-height: 1.8;
}

.kanji-example {
    margin: 0 3px;
    color: var(--vermilion-dark);
    font-family: "Noto Sans JP", sans-serif;
    font-size: 1.4em;
    font-weight: 700;
    vertical-align: middle;
}

.kanji-block {
    margin: 36px 0;
    padding: 32px;
    border: 1px solid var(--ink);
    background: var(--paper-bright);
    text-align: center;
}

.kanji-large {
    display: block;
    margin-bottom: 10px;
    color: var(--vermilion-dark);
    font-family: "Noto Sans JP", sans-serif;
    font-size: 3rem;
    font-weight: 700;
}

.kanji-reading,
.kanji-meaning {
    color: var(--muted);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.78rem;
}

.comparison-table {
    width: 100%;
    margin: 38px 0;
    border-collapse: collapse;
    border-top: 1px solid var(--ink);
    font-family: "Inter", ui-sans-serif, sans-serif;
}

.comparison-table th,
.comparison-table td {
    padding: 14px 16px;
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    font-size: 0.78rem;
    line-height: 1.55;
    text-align: left;
    vertical-align: top;
}

.comparison-table th:last-child,
.comparison-table td:last-child {
    border-right: 0;
}

.comparison-table th {
    background: var(--ink);
    color: var(--paper);
    font-size: 0.68rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.comparison-table .kanji-cell {
    color: var(--vermilion-dark);
    font-family: "Noto Sans JP", sans-serif;
    font-size: 1.06rem;
    font-weight: 700;
}

.article-body ul,
.article-body ol {
    margin: 24px 0 32px;
    padding: 0;
    list-style: none;
}

.article-body li {
    position: relative;
    margin: 0;
    padding: 10px 0 10px 30px;
    border-bottom: 1px solid var(--line);
    color: var(--ink-soft);
    font-size: 0.98rem;
    line-height: 1.7;
}

.article-body ul li::before {
    position: absolute;
    top: 19px;
    left: 7px;
    width: 7px;
    height: 7px;
    background: var(--vermilion);
    content: "";
}

.article-body ol {
    counter-reset: article-list;
}

.article-body ol li {
    counter-increment: article-list;
}

.article-body ol li::before {
    position: absolute;
    top: 11px;
    left: 3px;
    color: var(--vermilion-dark);
    content: counter(article-list, decimal-leading-zero);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.66rem;
    font-weight: 800;
}

.article-disclaimer {
    margin-top: 58px;
    padding: 22px 24px;
    border-top: 1px solid var(--ink);
    border-bottom: 1px solid var(--line);
    color: var(--muted);
    font-family: "Inter", ui-sans-serif, sans-serif;
    font-size: 0.76rem;
    line-height: 1.75;
}

.back-to-tool {
    display: inline-block;
    margin: 44px 0 72px;
    color: var(--ink);
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 0.09em;
    text-decoration: none;
    text-transform: uppercase;
}

.back-to-tool:hover {
    color: var(--vermilion-dark);
}

.related-articles {
    width: min(calc(100% - 48px), var(--article));
    margin: 0 auto;
    padding: 58px 0 72px;
    border-top: 1px solid var(--ink);
}

.related-articles h2 {
    margin: 0 0 26px;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.65rem;
}

.related-grid {
    display: grid;
    gap: 18px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.related-card {
    display: block;
    min-height: 160px;
    padding: 22px;
    border: 1px solid var(--line);
    background: var(--paper-bright);
    color: var(--ink);
    text-decoration: none;
    transition: border-color 180ms ease, transform 180ms ease;
}

.related-card:hover {
    border-color: var(--ink);
    transform: translateY(-3px);
}

.related-card-title {
    margin-bottom: 10px;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.15rem;
    font-weight: 700;
    line-height: 1.3;
}

.related-card-desc {
    color: var(--muted);
    font-size: 0.76rem;
    line-height: 1.65;
}

.article-cta {
    position: relative;
    margin-inline: calc(50% - 50vw);
    padding: 86px max(24px, calc((100vw - var(--wide)) / 2));
    overflow: hidden;
    background: var(--ink);
    color: var(--paper);
    text-align: center;
}

.article-cta::before {
    position: absolute;
    top: -80px;
    left: calc(50% - 300px);
    color: rgba(241, 238, 230, 0.045);
    content: "名";
    font-family: "Noto Sans JP", sans-serif;
    font-size: 28rem;
    font-weight: 700;
    line-height: 1;
    pointer-events: none;
}

.article-cta h2,
.article-cta p,
.article-cta .cta-btn {
    position: relative;
    z-index: 1;
}

.article-cta h2 {
    max-width: 760px;
    margin: 0 auto 18px;
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(2rem, 4vw, 3.5rem);
    font-weight: 500;
    letter-spacing: -0.04em;
    line-height: 1.05;
}

.article-cta p {
    max-width: 620px;
    margin: 0 auto 30px;
    color: #bcb7ab;
    font-size: 0.88rem;
}

.article-cta .cta-btn {
    display: inline-flex;
    min-height: 52px;
    align-items: center;
    padding: 0 22px;
    border: 1px solid var(--paper);
    background: var(--paper);
    color: var(--ink);
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.07em;
    text-decoration: none;
    text-transform: uppercase;
    transition: background-color 180ms ease, color 180ms ease;
}

.article-cta .cta-btn:hover {
    background: var(--vermilion);
    color: #fff;
}

#column-footer {
    width: min(calc(100% - 48px), var(--wide));
    margin: 0 auto;
}

.column-footer {
    display: grid;
    gap: 22px;
    padding: 52px 0 42px;
    color: var(--muted);
    font-size: 0.75rem;
}

.column-footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 24px;
}

.column-footer a {
    color: var(--ink);
}

.column-footer p {
    margin: 0;
}

@media (max-width: 780px) {
    .column-site-header,
    .column-index,
    .column-article,
    .related-articles,
    #column-footer {
        width: min(calc(100% - 36px), var(--wide));
    }

    .column-index-header {
        align-items: start;
        gap: 34px;
        grid-template-columns: 1fr;
    }

    .column-list {
        grid-template-columns: 1fr;
    }

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

    .comparison-table {
        display: block;
        width: 100%;
        overflow-x: auto;
        white-space: nowrap;
        -webkit-overflow-scrolling: touch;
    }
}

@media (max-width: 560px) {
    .column-site-header,
    .column-index,
    .column-article,
    .related-articles,
    #column-footer {
        width: min(calc(100% - 28px), var(--wide));
    }

    .column-site-header {
        min-height: 82px;
    }

    .column-wordmark small,
    .column-site-header nav a:first-child {
        display: none;
    }

    .column-tool-link {
        min-height: 36px;
        gap: 9px;
        padding-inline: 11px;
        font-size: 0.61rem !important;
    }

    .column-index-header {
        padding: 62px 0 56px;
    }

    .column-index-header h1 {
        font-size: clamp(3.4rem, 16vw, 4.7rem);
    }

    .column-list {
        margin-top: 48px;
    }

    .article-breadcrumb {
        margin-bottom: 38px;
        padding-top: 34px;
        line-height: 1.8;
    }

    .article-header h1 {
        font-size: clamp(2.55rem, 13vw, 3.65rem);
    }

    .article-meta {
        display: grid;
        gap: 8px 14px;
        grid-template-columns: auto auto auto;
        justify-content: start;
        font-size: 0.61rem;
    }

    .article-meta > * {
        white-space: nowrap;
    }

    .article-meta .meta-divider {
        display: none;
    }

    .article-hero-image {
        margin-bottom: 46px;
    }

    .article-body h2 {
        margin-top: 54px;
    }

    .key-point,
    .warning-box {
        padding: 22px 20px;
    }

    .comparison-table th,
    .comparison-table td {
        padding: 11px 13px;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}