/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
    font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
                 "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    font-size: 16px;
    line-height: 1.55;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    transition: background-color 120ms ease, color 120ms ease;
}
img { max-width: 100%; display: block; }
button { font: inherit; cursor: pointer; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); }

/* ===== Theme tokens ===== */
:root {
    --accent: #F97316;
    --accent-hover: #EA580C;
    --accent-soft: rgba(249, 115, 22, 0.12);
    --radius: 6px;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 1px 3px rgba(0, 0, 0, 0.06);
}

:root[data-theme="light"] {
    --bg:        #FFFFFF;
    --bg-2:      #FAFAFA;
    --bg-3:      #F4F4F5;
    --text:      #18181B;
    --text-muted:#71717A;
    --border:    #E4E4E7;
    --border-strong: #D4D4D8;
}

:root[data-theme="dark"] {
    --bg:        #18181B;
    --bg-2:      #1F1F22;
    --bg-3:      #27272A;
    --text:      #FAFAFA;
    --text-muted:#A1A1AA;
    --border:    #2F2F33;
    --border-strong: #3F3F46;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 1px 3px rgba(0, 0, 0, 0.3);
}

/* ===== Layout ===== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Header ===== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    backdrop-filter: saturate(180%) blur(12px);
}
.site-header .container {
    display: flex;
    align-items: center;
    gap: 24px;
    height: 64px;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 17px;
    letter-spacing: -0.01em;
    color: var(--text);
}
.brand:hover { color: var(--text); }
.brand-mark {
    width: 8px; height: 8px;
    background: var(--accent);
    border-radius: 2px;
}
.nav-links {
    display: flex;
    gap: 24px;
    margin-left: 32px;
    list-style: none;
    padding: 0;
}
.nav-links a {
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 500;
    transition: color 120ms ease;
}
.nav-links a:hover { color: var(--text); }
.header-actions {
    margin-left: auto;
    display: flex;
    gap: 8px;
    align-items: center;
}

/* ===== Theme toggle ===== */
.icon-btn {
    width: 36px; height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text);
    transition: background 120ms ease, border-color 120ms ease;
}
.icon-btn:hover {
    background: var(--bg-3);
    border-color: var(--border-strong);
}
.icon-btn svg { width: 18px; height: 18px; }
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* ===== Page heading ===== */
.page {
    padding: 40px 0 64px;
}
.page-title {
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 28px;
    color: var(--text);
}
.page-subtitle {
    font-size: 18px;
    font-weight: 600;
    color: var(--text);
    margin: 40px 0 16px;
}

/* ===== Article grid ===== */
.grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}
@media (max-width: 720px) {
    .grid { grid-template-columns: 1fr; }
}

/* ===== Card ===== */
.card {
    display: flex;
    flex-direction: column;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px 22px;
    transition: border-color 120ms ease, transform 120ms ease;
    cursor: pointer;
    position: relative;
}
.card:hover {
    border-color: var(--accent);
}
.card::before {
    content: "";
    position: absolute;
    left: 0; top: 0; bottom: 0;
    width: 3px;
    background: var(--accent);
    border-top-left-radius: var(--radius);
    border-bottom-left-radius: var(--radius);
    opacity: 0;
    transition: opacity 120ms ease;
}
.card:hover::before { opacity: 1; }

.card-title {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.35;
    margin: 0 0 10px;
    letter-spacing: -0.01em;
}
.card-title a {
    color: var(--text);
}
.card-title a:hover { color: var(--accent); }

.card-announce {
    color: var(--text);
    font-size: 14.5px;
    margin: 0 0 16px;
}
.card-original {
    margin: auto 0 0;
    padding: 14px 0 0;
    border-top: 1px dashed var(--border);
    color: var(--text-muted);
    font-size: 13px;
}
.card-original-title { color: var(--text); font-weight: 600; }
.card-original-desc { font-style: normal; }

.card-meta {
    margin-top: 14px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    gap: 12px;
    font-size: 12.5px;
    color: var(--text-muted);
    align-items: center;
    flex-wrap: wrap;
}
.card-meta a {
    color: var(--text-muted);
    border-bottom: 1px solid transparent;
}
.card-meta a:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}
.card-meta time { font-variant-numeric: tabular-nums; }

/* ===== Article view ===== */
.article {
    max-width: 760px;
    margin: 0 auto 56px;
}
.article-header {
    margin-bottom: 28px;
}
.article-title {
    font-size: 36px;
    line-height: 1.18;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 14px;
    color: var(--text);
}
.article-meta {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    color: var(--text-muted);
    font-size: 14px;
}
.article-meta .accent { color: var(--accent); font-weight: 500; }
.article-body {
    font-size: 17px;
    line-height: 1.7;
    color: var(--text);
}
.article-body p { margin: 0 0 1em; }

.article-actions {
    margin: 36px 0 0;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 16px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--bg);
    color: var(--text);
    font-size: 14px;
    font-weight: 500;
    transition: background 120ms ease, border-color 120ms ease, color 120ms ease;
}
.btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}
.btn-primary {
    background: var(--accent);
    border-color: var(--accent);
    color: #FFFFFF;
}
.btn-primary:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
    color: #FFFFFF;
}

.original {
    margin-top: 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    background: var(--bg-2);
    display: none;
}
.original.open { display: block; }
.original h3 {
    font-size: 18px;
    font-weight: 600;
    margin: 0 0 12px;
}
.original-body {
    font-size: 15px;
    line-height: 1.65;
    color: var(--text);
}

/* ===== Empty / status ===== */
.notice {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px 24px;
    text-align: center;
    color: var(--text-muted);
}
.notice h2 {
    font-size: 22px;
    font-weight: 600;
    color: var(--text);
    margin: 0 0 8px;
}
.notice p { margin: 0 0 16px; }

/* ===== Footer ===== */
.site-footer {
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 13px;
    padding: 24px 0;
    margin-top: 48px;
}
.site-footer .container {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

/* ===== Loader ===== */
.loader {
    height: 1px;
    width: 100%;
}