@charset "utf-8";

@import url("https://fonts.googleapis.com/css2?family=Shippori+Mincho:wght@500;600;700&family=Zen+Kaku+Gothic+New:wght@400;500;700&display=swap");

:root {
    --bg: #fff9f3;
    --ink: #2c332e;
    --muted: #5e6a62;
    --green: #3f8f5c;
    --green-deep: #2f6b45;
    --sage: #cfdcd2;
    --mint: #e4f3e8;
    --line: #d5e0d8;
    --orange: #ec8747;
    --paper: #fffdf9;
    --serif: "Shippori Mincho", "Yu Mincho", "Hiragino Mincho ProN", serif;
    --sans: "Zen Kaku Gothic New", "Hiragino Sans", "Noto Sans JP", sans-serif;
}

html {
    background: var(--bg);
}

body {
    max-width: 1040px;
    margin: 0 auto;
    padding: 1.5rem clamp(1.15rem, 4vw, 2.75rem) 4.5rem;
    background: var(--bg);
    color: var(--ink);
    font-family: var(--sans);
    font-size: 16px;
    line-height: 1.9;
    font-weight: 400;
}

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

a {
    color: inherit;
    text-decoration: none;
}

a:hover {
    color: var(--green-deep);
}

:focus-visible {
    outline: 2px solid var(--green);
    outline-offset: 3px;
}

.site-header,
.header {
    margin: 0;
    padding: 0.35rem 0 0;
    font-family: var(--serif);
    font-size: 1.35rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    color: var(--green-deep);
}

.brand,
.header-link {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    color: var(--green-deep);
}

.brand img,
.header-link img,
.header img {
    height: 1.65rem;
    width: auto;
}

.navpc,
.navsm {
    border-bottom: 1px solid var(--line);
}

.navpc {
    display: flex;
    justify-content: flex-end;
    flex-wrap: wrap;
    gap: 0.35rem 1.35rem;
    padding: 0.85rem 0 0.95rem;
    margin-top: 0.35rem;
}

.navpc a,
.navsm a {
    color: var(--green-deep);
    font-size: 0.92rem;
    letter-spacing: 0.04em;
}

.navpc a:hover,
.navsm a:hover {
    color: var(--orange);
}

.navsm {
    display: none;
}

.navsm summary {
    cursor: pointer;
    list-style: none;
    width: fit-content;
    color: var(--green-deep);
    letter-spacing: 0.14em;
    font-size: 0.82rem;
    padding: 0.35rem 0 0.85rem;
}

.navsm summary::-webkit-details-marker {
    display: none;
}

.navsm a {
    display: block;
    padding: 0.45rem 0;
    border-top: 1px solid var(--line);
}

.hero {
    text-align: center;
    padding: 4.2rem 0.5rem 3.2rem;
}

.hero-kicker {
    margin: 0;
    color: var(--green);
    font-size: 0.92rem;
    letter-spacing: 0.18em;
}

.hero h1 {
    margin: 0.85rem 0 0;
    font-family: var(--serif);
    font-weight: 600;
    font-size: clamp(2.15rem, 5.4vw, 3.35rem);
    letter-spacing: 0.12em;
    color: var(--green-deep);
    line-height: 1.35;
}

.hero-label {
    margin: 1rem 0 0;
    color: var(--green);
    letter-spacing: 0.16em;
    font-size: 0.95rem;
}

.hero-lead {
    max-width: 34rem;
    margin: 2.6rem auto 0;
    padding-top: 1.35rem;
    border-top: 1px solid var(--line);
    color: var(--ink);
    line-height: 2;
}

.section,
.content {
    margin-top: 3.4rem;
}

.kicker {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    margin: 0;
    color: var(--green);
    font-size: 0.82rem;
    letter-spacing: 0.14em;
}

.kicker img {
    height: 0.95rem;
    width: auto;
    flex: none;
}

.section h2,
.section h3.follow,
.title {
    margin: 0.4rem 0 0;
    font-family: var(--serif);
    font-weight: 600;
    font-size: clamp(1.65rem, 3vw, 2.05rem);
    letter-spacing: 0.06em;
    color: var(--green-deep);
    line-height: 1.45;
}

.section h3.follow {
    margin-top: 3rem;
    font-size: clamp(1.45rem, 2.6vw, 1.75rem);
}

.accent {
    width: 2.2rem;
    height: 3px;
    margin: 0.85rem 0 1.35rem;
    border: 0;
    background: var(--orange);
}

.title {
    margin-bottom: 0.35rem;
}

.title::after {
    content: "";
    display: block;
    width: 2.2rem;
    height: 3px;
    margin-top: 0.75rem;
    background: var(--orange);
}

.lead,
.highlight {
    color: var(--green-deep);
    font-weight: 500;
    font-size: 1.05rem;
    line-height: 1.85;
}

.section p,
.content p {
    margin: 0.85rem 0;
}

.note {
    margin-top: 1.25rem;
    padding: 1rem 1.15rem;
    background: var(--mint);
    color: var(--green-deep);
    font-size: 0.92rem;
}

.figure {
    margin: 2rem 0 0.4rem;
}

.figure img,
.event,
.attempt,
.operation,
.scheme {
    display: block;
    width: min(100%, 920px);
    margin-inline: auto;
    background: var(--paper);
}

.caption {
    margin: 0.7rem 0 0;
    text-align: center;
    color: var(--muted);
    font-size: 0.85rem;
    letter-spacing: 0.12em;
}

.pillars {
    margin-top: 1.5rem;
}

.pillar {
    display: grid;
    grid-template-columns: minmax(140px, 210px) 1fr;
    gap: 1.35rem 1.6rem;
    align-items: start;
    padding: 1.45rem 0;
    border-top: 1px solid var(--line);
}

.pillar img {
    width: 100%;
    aspect-ratio: 4 / 3;
    object-fit: cover;
}

.pillar-label {
    margin: 0;
    color: var(--green);
    font-size: 0.82rem;
    letter-spacing: 0.08em;
}

.pillar h3 {
    margin: 0.2rem 0 0.45rem;
    font-family: var(--serif);
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--green-deep);
    letter-spacing: 0.05em;
}

.pillar p {
    margin: 0;
}

.button,
.tsubameapp a {
    display: inline-block;
    margin-top: 0.95rem;
    padding: 0.55rem 1.15rem;
    border-radius: 999px;
    background: var(--green);
    color: #fff;
    font-size: 0.92rem;
    letter-spacing: 0.04em;
}

.button:hover,
.tsubameapp a:hover,
.tsubameapp:hover {
    background: var(--green-deep);
    color: #fff;
    opacity: 1;
}

.tsubameapp {
    display: inline-flex;
    width: auto;
    height: auto;
    margin-top: 0.4rem;
    background: transparent;
    border-radius: 0;
}

.news-list,
.past-list {
    list-style: none;
    margin: 0.4rem 0 0;
    padding: 0;
}

.news-list li,
.past-list li {
    border-top: 1px solid var(--line);
}

.news-list li:last-child,
.past-list li:last-child {
    border-bottom: 1px solid var(--line);
}

.news-list a,
.past-list a {
    display: grid;
    grid-template-columns: 8.6rem 1fr;
    gap: 0.15rem 1.2rem;
    padding: 1.05rem 0.15rem;
    color: var(--ink);
}

.news-list a:hover,
.past-list a:hover {
    color: var(--green-deep);
}

.news-list time,
.past-list time {
    color: var(--green);
    font-size: 0.92rem;
    letter-spacing: 0.03em;
}

.news-meta {
    display: block;
    color: var(--muted);
    font-size: 0.86rem;
}

.news-title {
    display: block;
    font-weight: 500;
}

.teacher {
    display: block;
    margin-top: 0.35rem;
    color: var(--muted);
    font-size: 0.82rem;
    font-weight: 400;
    line-height: 1.7;
}

#news > a {
    display: block;
    padding: 0.85rem 0;
    border-top: 1px solid var(--line);
    color: var(--ink);
}

#news > a:last-of-type {
    border-bottom: 1px solid var(--line);
}

#news .highlight {
    margin: 0;
    font-size: 1rem;
    font-weight: 500;
}

.app-card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1.25rem;
    margin-top: 0.6rem;
    padding: 1.35rem 1.4rem;
    background: var(--mint);
}

.app-card p {
    margin: 0.35rem 0 0;
}

.app-card .button {
    margin-top: 0;
    flex: none;
}

.site-footer {
    margin-top: 3.5rem;
    padding-top: 0.4rem;
    color: var(--muted);
    font-size: 0.88rem;
}

.site-footer .navpc,
.site-footer .navsm {
    border-bottom: 0;
    border-top: 1px solid var(--line);
}

.site-footer p {
    margin: 1rem 0 0;
    letter-spacing: 0.04em;
}

.form {
    max-width: 38rem;
}

.form h2,
.form .title {
    margin-bottom: 0;
}

.field {
    margin: 1.15rem 0;
}

.field label,
.form h3 {
    display: block;
    margin: 0 0 0.35rem;
    color: var(--green-deep);
    font-size: 0.95rem;
    font-weight: 500;
}

.req {
    color: var(--orange);
    font-size: 0.8rem;
    margin-left: 0.25rem;
}

.field input,
.field select,
.field textarea,
.form input[type="text"],
.form select,
.form textarea {
    display: block;
    width: min(100%, 28rem);
    margin: 0;
    padding: 0.65rem 0.75rem;
    border: 1px solid var(--sage);
    border-radius: 2px;
    background: var(--paper);
    color: var(--ink);
    font: inherit;
}

.field textarea,
.form textarea {
    min-height: 11rem;
    resize: vertical;
}

.submit,
input[type="submit"].submit {
    margin: 0.5rem 0 0;
    padding: 0.7rem 1.4rem;
    border: 0;
    border-radius: 999px;
    background: var(--green);
    color: #fff;
    font: inherit;
    letter-spacing: 0.06em;
    cursor: pointer;
}

.submit:hover {
    background: var(--green-deep);
    opacity: 1;
}

.form-note {
    color: var(--muted);
    font-size: 0.88rem;
}

.thanks-message {
    font-family: var(--serif);
    font-size: 1.45rem;
    color: var(--green-deep);
    line-height: 1.8;
}

.container,
.container1,
.container2,
.container3 {
    display: block;
}

.item2 img {
    width: min(100%, 360px);
    margin: 0.5rem 0 1rem;
}

.pair {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin: 1rem 0;
}

.article-photo {
    width: 100%;
    margin: 0;
}

.gap {
    height: 1.25rem;
}

#bottombar {
    margin-top: 2rem;
    padding: 1rem 0 0.2rem;
    background: var(--green-deep);
    color: #fff;
    border-radius: 2px;
}

#bottombar a,
.blacklinks,
.privacypolicylink {
    color: #fff;
}

@media screen and (max-width: 760px) {
    .navpc {
        display: none;
    }

    .navsm {
        display: block;
    }

    .hero {
        padding: 2.8rem 0 2.2rem;
        text-align: left;
    }

    .hero-lead {
        margin-left: 0;
    }

    .pillar,
    .news-list a,
    .past-list a,
    .app-card {
        grid-template-columns: 1fr;
        display: grid;
    }

    .app-card {
        align-items: start;
    }

    .item2 img {
        width: 100%;
    }

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