:root {
    --teal: #0b7f7d;
    --teal-dark: #075f5e;
    --teal-light: #e7f5f4;
    --orange: #d85d16;
    --ink: #263238;
    --muted: #58666b;
    --paper: rgba(255, 255, 255, 0.96);
    --line: #c8dcdb;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    color: var(--ink);
    font-family: Arial, Helvetica, sans-serif;
    font-size: 17px;
    line-height: 1.65;
    background:
        linear-gradient(rgba(255,255,255,0.72), rgba(255,255,255,0.72)),
        url('background.jpg') center / cover fixed;
}

a { color: #066f9b; }
a:hover { color: #034f70; }
a:focus-visible { outline: 3px solid #f59e0b; outline-offset: 3px; }

.site-header {
    border-bottom: 1px solid var(--line);
    background: rgba(255,255,255,0.94);
}

.site-header-inner {
    width: min(100% - 32px, 980px);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 10px 0;
}

.brand-logo {
    width: 420px;
    max-width: 64vw;
    height: 100px;
    display: block;
    object-fit: cover;
    object-position: center;
}

.top-link {
    color: var(--teal-dark);
    font-size: 15px;
    font-weight: 700;
    text-decoration: none;
}

.page-shell {
    width: min(100% - 28px, 860px);
    margin: 28px auto 48px;
    padding: 34px clamp(20px, 5vw, 58px) 44px;
    border: 1px solid rgba(11,127,125,0.2);
    border-radius: 14px;
    background: var(--paper);
    box-shadow: 0 12px 36px rgba(24, 64, 70, 0.12);
}

.series-label {
    margin: 0 0 4px;
    color: var(--teal-dark);
    font-size: 15px;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

h1, h2, h3 { line-height: 1.22; }
h1 { margin: 0 0 12px; font-size: clamp(32px, 6vw, 46px); }
h2 { margin: 40px 0 12px; color: var(--teal-dark); font-size: clamp(23px, 4vw, 29px); }
h3 { margin: 28px 0 10px; font-size: 20px; }
p { margin: 0 0 16px; }
ul { margin: 8px 0 20px; padding-left: 25px; }
li { margin: 5px 0; }

.intro {
    margin: 0 0 26px;
    color: var(--muted);
    font-size: 19px;
}

.translation-note {
    margin: 20px 0 26px;
    padding: 15px 18px;
    border: 1px solid var(--line);
    border-radius: 9px;
    background: #f7fbfb;
    font-size: 15px;
}

.translation-note > strong {
    display: block;
    margin-bottom: 3px;
    color: var(--teal-dark);
    font-size: 17px;
}

.translation-note p { margin: 0; }

.short-answer,
.key-point,
.next-up,
.about-box {
    margin: 24px 0;
    padding: 20px 22px;
    border-radius: 10px;
}

.short-answer { border-left: 6px solid var(--orange); background: #fff6ef; }
.short-answer h2, .key-point h2, .next-up h2, .about-box h2 { margin-top: 0; }
.key-point { border: 2px solid var(--teal); background: var(--teal-light); }
.next-up { border-left: 6px solid var(--teal); background: #f2fafa; }
.about-box { margin-top: 34px; border-top: 4px solid var(--teal); background: #f5f7f7; font-size: 15px; }

.flow {
    margin: 20px 0;
    padding: 16px;
    border-radius: 8px;
    background: var(--teal-light);
    font-weight: 700;
    text-align: center;
}

.article-nav {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    margin: 26px 0;
}

.button, .topic-card {
    border-radius: 9px;
    color: white;
    background: var(--teal);
    font-weight: 700;
    text-decoration: none;
}

.button { display: inline-block; padding: 10px 16px; }
.button:hover, .topic-card:hover { color: white; background: var(--teal-dark); }

.topic-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin: 24px 0; }
.topic-card { display: block; padding: 20px; }
.topic-card span { display: block; margin-top: 6px; color: rgba(255,255,255,0.86); font-size: 14px; font-weight: 400; }
.topic-card.coming { color: var(--ink); background: #edf2f2; }
.topic-card.coming span { color: var(--muted); }

.sources { font-size: 15px; }
.updated { margin-top: 28px; color: var(--muted); font-size: 14px; }

@media (max-width: 640px) {
    body { font-size: 16px; background-attachment: scroll; }
    .site-header-inner { align-items: flex-start; flex-direction: column; gap: 4px; }
    .brand-logo { max-width: 88vw; height: 78px; }
    .page-shell { margin-top: 14px; padding-top: 26px; }
    .topic-grid { grid-template-columns: 1fr; }
    .article-nav { flex-direction: column; }
    .button { text-align: center; }
}