.relations-page { overflow-x: hidden; }
.relations-page [hidden] { display: none !important; }
.relation-main { min-height: calc(100vh - 160px); }

.relation-visit-strip { padding-block: 18px 14px; }
.relation-visit-strip .visitor-summary { margin-top: 0; }

.relation-workspace { padding-bottom: 76px; scroll-margin-top: 92px; }
.knowledge-panel {
    min-width: 0;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: rgba(8, 22, 37, .92);
    box-shadow: var(--shadow);
}
.knowledge-toolbar {
    position: relative;
    z-index: 20;
    display: grid;
    grid-template-columns: minmax(220px, 1fr) minmax(280px, 430px) auto;
    align-items: center;
    gap: 18px;
    padding: 19px 22px;
    border-bottom: 1px solid var(--line);
    background: rgba(9, 24, 40, .94);
}
.knowledge-toolbar h1 { margin: 0; font-size: 25px; line-height: 1.1; }
.knowledge-search { position: relative; }
.knowledge-search > label {
    display: block;
    margin-bottom: 5px;
    color: var(--muted);
    font-size: 10px;
    font-weight: 700;
    letter-spacing: .09em;
}
.search-input-wrap { position: relative; }
.search-input-wrap input {
    width: 100%;
    height: 44px;
    padding: 0 68px 0 14px;
    color: var(--text);
    border: 1px solid var(--line-strong);
    border-radius: 11px;
    outline: none;
    background: rgba(3, 13, 23, .72);
}
.search-input-wrap input:focus { border-color: rgba(88, 228, 223, .76); box-shadow: 0 0 0 3px rgba(88, 228, 223, .1); }
.search-input-wrap kbd {
    position: absolute;
    top: 9px;
    right: 10px;
    padding: 3px 7px;
    color: var(--muted);
    border: 1px solid var(--line);
    border-radius: 6px;
    background: rgba(255, 255, 255, .04);
    font: 600 10px/1.4 inherit;
}
.search-results {
    position: absolute;
    z-index: 40;
    top: calc(100% + 8px);
    left: 0;
    width: 100%;
    max-height: 420px;
    padding: 7px;
    overflow-y: auto;
    border: 1px solid var(--line-strong);
    border-radius: 13px;
    background: #0b1b2d;
    box-shadow: 0 22px 65px rgba(0, 0, 0, .48);
}
.search-result {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    width: 100%;
    padding: 10px 11px;
    color: var(--text);
    border: 0;
    border-left: 3px solid var(--chapter-color);
    border-radius: 8px;
    background: transparent;
    text-align: left;
    cursor: pointer;
}
.search-result + .search-result { margin-top: 3px; }
.search-result:hover, .search-result[aria-selected="true"] { background: rgba(255, 255, 255, .07); }
.search-result span, .search-result strong, .search-result small { display: block; }
.search-result strong { font-size: 12px; }
.search-result small { max-width: 275px; overflow: hidden; color: var(--muted); font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }
.search-result em { flex: 0 0 auto; color: var(--chapter-color); font-size: 9px; font-style: normal; }
.search-empty { margin: 0; padding: 20px; color: var(--muted); text-align: center; font-size: 12px; }
.overview-button, .depth-toggle {
    min-height: 42px;
    padding: 0 14px;
    border: 1px solid var(--line-strong);
    border-radius: 10px;
    background: rgba(255, 255, 255, .04);
    cursor: pointer;
}
.overview-button:hover, .overview-button:focus-visible, .depth-toggle:hover, .depth-toggle:focus-visible { border-color: var(--cyan); }

.chapter-overview { padding: 24px; }
.section-heading {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 24px;
    margin-bottom: 18px;
}
.section-heading h3 { margin: 2px 0 0; font-size: 26px; }
.section-heading p { max-width: 480px; margin: 0; color: var(--muted); font-size: 13px; text-align: right; }
.section-kicker { color: var(--cyan); font-size: 10px; font-weight: 760; letter-spacing: .13em; }
.chapter-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.chapter-card {
    position: relative;
    min-width: 0;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: linear-gradient(145deg, color-mix(in srgb, var(--chapter-color) 8%, transparent), rgba(255, 255, 255, .018));
    transition: border-color 160ms ease, transform 160ms ease, background 160ms ease;
}
.chapter-card::before {
    position: absolute;
    top: 0;
    right: 0;
    left: 0;
    height: 2px;
    background: var(--chapter-color);
    content: "";
    opacity: .7;
}
.chapter-card:hover { transform: translateY(-2px); border-color: color-mix(in srgb, var(--chapter-color) 52%, transparent); }
.chapter-card.active { border-color: var(--chapter-color); background: color-mix(in srgb, var(--chapter-color) 10%, rgba(8, 22, 37, .95)); }
.chapter-open {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) auto;
    align-items: center;
    gap: 11px;
    width: 100%;
    padding: 16px 15px 12px;
    border: 0;
    background: transparent;
    text-align: left;
    cursor: pointer;
}
.chapter-number {
    color: var(--chapter-color);
    font-size: 21px;
    font-weight: 800;
    font-variant-numeric: tabular-nums;
}
.chapter-copy, .chapter-copy strong, .chapter-copy small { display: block; min-width: 0; }
.chapter-copy strong { overflow: hidden; font-size: 14px; text-overflow: ellipsis; white-space: nowrap; }
.chapter-copy small { margin-top: 2px; color: var(--muted); font-size: 9px; }
.chapter-arrow { color: var(--chapter-color); font-size: 15px; transition: transform 160ms ease; }
.chapter-card.active .chapter-arrow { transform: rotate(45deg); }
.chapter-metrics { display: grid; grid-template-columns: repeat(2, 1fr); margin: 0 15px; border-block: 1px solid var(--line); }
.chapter-metrics div { padding: 10px 0; }
.chapter-metrics div + div { padding-left: 12px; border-left: 1px solid var(--line); }
.chapter-metrics dt { font-size: 16px; font-weight: 750; }
.chapter-metrics dd { margin: 1px 0 0; color: var(--muted); font-size: 9px; }
.chapter-hot-rules { display: grid; gap: 4px; padding: 11px 15px 14px; }
.hot-label { margin-bottom: 2px; color: var(--muted); font-size: 8px; font-weight: 700; letter-spacing: .08em; }
.hot-rule {
    min-width: 0;
    overflow: hidden;
    padding: 3px 0;
    color: #cfdeeb;
    border: 0;
    background: transparent;
    font-size: 10px;
    text-align: left;
    text-overflow: ellipsis;
    white-space: nowrap;
    cursor: pointer;
}
.hot-rule:hover, .hot-rule:focus-visible { color: var(--chapter-color); }

.chapter-browser {
    margin-top: 16px;
    padding: 18px;
    border: 1px solid var(--line-strong);
    border-radius: 16px;
    background: rgba(4, 15, 26, .66);
}
.chapter-browser-heading { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 12px; }
.chapter-browser-heading span { color: var(--cyan); font-size: 9px; font-weight: 750; letter-spacing: .12em; }
.chapter-browser-heading h3 { margin: 2px 0 0; font-size: 20px; }
.chapter-browser-heading button {
    padding: 7px 11px;
    color: var(--muted);
    border: 1px solid var(--line);
    border-radius: 8px;
    background: transparent;
    cursor: pointer;
}
.chapter-main-rules { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; }
.chapter-main-rule {
    display: grid;
    gap: 3px;
    min-width: 0;
    padding: 11px 12px;
    color: var(--text);
    border: 1px solid var(--line);
    border-left: 3px solid var(--chapter-color);
    border-radius: 10px;
    background: rgba(255, 255, 255, .025);
    text-align: left;
    cursor: pointer;
}
.chapter-main-rule:hover, .chapter-main-rule:focus-visible { border-color: var(--chapter-color); background: color-mix(in srgb, var(--chapter-color) 8%, transparent); }
.compact-rule-number { color: var(--chapter-color); font-size: 9px; font-weight: 750; }
.compact-rule-label { overflow: hidden; font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }

.rule-explorer { scroll-margin-top: 92px; }
.explorer-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 12px 22px;
    border-bottom: 1px solid var(--line);
    background: rgba(5, 17, 29, .72);
}
.rule-breadcrumb { display: flex; align-items: center; flex-wrap: wrap; gap: 7px; min-width: 0; color: var(--muted); font-size: 11px; }
.rule-breadcrumb button { padding: 3px 5px; color: inherit; border: 0; border-radius: 5px; background: transparent; cursor: pointer; }
.rule-breadcrumb button:hover, .rule-breadcrumb button:focus-visible { color: var(--cyan); background: rgba(88, 228, 223, .07); }
.breadcrumb-chapter { color: var(--cyan) !important; font-weight: 700; }
.breadcrumb-current { color: var(--text); font-weight: 760; }
.breadcrumb-separator { opacity: .45; }
.depth-toggle { display: inline-flex; align-items: center; gap: 8px; flex: 0 0 auto; color: var(--muted); font-size: 11px; }
.depth-toggle span { width: 8px; height: 8px; border: 1px solid var(--line-strong); border-radius: 50%; background: transparent; }
.depth-toggle[aria-pressed="true"] { color: var(--text); border-color: rgba(88, 228, 223, .54); background: rgba(88, 228, 223, .08); }
.depth-toggle[aria-pressed="true"] span { border-color: var(--cyan); background: var(--cyan); box-shadow: 0 0 0 4px rgba(88, 228, 223, .1); }
.relation-key { display: flex; flex-wrap: wrap; gap: 17px; padding: 10px 22px; color: var(--muted); border-bottom: 1px solid var(--line); font-size: 10px; }
.relation-key span { display: inline-flex; align-items: center; gap: 6px; }
.relation-key i { width: 22px; border-top: 2px solid currentColor; }
.relation-key .incoming-key { color: var(--orange); }
.relation-key .outgoing-key { color: var(--cyan); }

.relation-diagram {
    position: relative;
    display: grid;
    grid-template-columns: minmax(250px, 1fr) minmax(310px, .86fr) minmax(250px, 1fr);
    align-items: stretch;
    gap: clamp(48px, 5.2vw, 84px);
    min-height: 720px;
    padding: 20px;
    background:
        linear-gradient(rgba(70, 120, 160, .035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(70, 120, 160, .035) 1px, transparent 1px),
        radial-gradient(circle at center, rgba(57, 167, 255, .09), transparent 34rem),
        #07131f;
    background-size: 42px 42px, 42px 42px, auto, auto;
}
.relation-lines { position: absolute; z-index: 0; inset: 0; width: 100%; height: 100%; overflow: visible; pointer-events: none; }
.connector { fill: none; stroke-width: 1.45; stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.connector.incoming { stroke: rgba(255, 158, 91, .54); }
.connector.outgoing { stroke: rgba(88, 228, 223, .52); }
.relation-column, .current-column { position: relative; z-index: 2; min-width: 0; }
.relation-column {
    display: flex;
    min-height: 0;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 15px;
    background: rgba(5, 17, 29, .8);
    flex-direction: column;
}
.incoming-column { border-top-color: rgba(255, 158, 91, .52); }
.outgoing-column { border-top-color: rgba(88, 228, 223, .52); }
.column-heading {
    position: relative;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: end;
    padding: 15px 15px 12px;
    border-bottom: 1px solid var(--line);
    background: rgba(10, 26, 43, .94);
}
.column-heading h3 { margin: 2px 0 0; font-size: 17px; }
.column-heading strong {
    grid-row: 1 / span 2;
    grid-column: 2;
    align-self: center;
    min-width: 34px;
    padding: 3px 8px;
    border-radius: 999px;
    background: rgba(255, 255, 255, .055);
    font-size: 13px;
    text-align: center;
}
.column-direction { grid-column: 1; font-size: 9px; font-weight: 750; letter-spacing: .08em; }
.column-direction.incoming { color: var(--orange); }
.column-direction.outgoing { color: var(--cyan); }
.relation-list { flex: 1; max-height: 650px; padding: 11px; overflow-y: auto; overscroll-behavior: contain; scrollbar-color: rgba(157, 184, 211, .25) transparent; scrollbar-width: thin; }
.relation-group + .relation-group { margin-top: 12px; }
.relation-group h4 {
    display: flex;
    align-items: center;
    gap: 6px;
    margin: 0 0 6px;
    padding: 0 3px;
    color: var(--muted);
    font-size: 9px;
    font-weight: 650;
}
.relation-group h4 i { width: 6px; height: 6px; border-radius: 50%; }
.relation-group h4 span { margin-left: auto; color: #dce8f2; }
.relation-node {
    position: relative;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 10px;
    background: rgba(255, 255, 255, .026);
}
.relation-node + .relation-node { margin-top: 6px; }
.relation-node::before { position: absolute; z-index: 2; top: 0; bottom: 0; left: 0; width: 2px; background: var(--chapter-color); content: ""; opacity: .75; }
.relation-node:hover { border-color: color-mix(in srgb, var(--chapter-color) 46%, transparent); }
.relation-node.expanded { border-color: color-mix(in srgb, var(--chapter-color) 60%, transparent); background: color-mix(in srgb, var(--chapter-color) 5%, rgba(6, 17, 29, .92)); }
.relation-rule-button {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: start;
    gap: 9px;
    width: 100%;
    padding: 10px 10px 9px 12px;
    color: inherit;
    border: 0;
    background: transparent;
    text-align: left;
    cursor: pointer;
}
.relation-rule-button:hover, .relation-rule-button:focus-visible { background: rgba(255, 255, 255, .045); outline: none; }
.relation-rule-copy, .relation-rule-copy span, .relation-rule-copy strong { display: block; min-width: 0; }
.relation-rule-number { color: var(--chapter-color); font-size: 9px; font-weight: 760; }
.relation-rule-copy strong {
    display: -webkit-box;
    margin-top: 2px;
    overflow: hidden;
    font-size: 11px;
    line-height: 1.45;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}
.relation-rule-preview {
    display: -webkit-box;
    margin: 6px 0 0;
    max-height: calc(1.55em * 3);
    overflow: hidden;
    color: var(--muted);
    font-size: 10px;
    line-height: 1.55;
    white-space: pre-line;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 3;
}
.relation-node.text-expanded .relation-rule-copy strong,
.relation-node.text-expanded .relation-rule-preview {
    display: block;
    max-height: none;
    overflow: visible;
    -webkit-line-clamp: unset;
}
.relation-degree {
    display: grid;
    width: 25px;
    height: 25px;
    place-items: center;
    color: var(--muted);
    border: 1px solid var(--line);
    border-radius: 50%;
    font-size: 9px;
    font-weight: 700;
    margin-top: 7px;
}
.relation-text-toggle,
.second-text-toggle {
    width: 100%;
    padding: 7px 11px;
    color: var(--cyan);
    border: 0;
    border-top: 1px solid var(--line);
    background: rgba(88, 228, 223, .035);
    font-size: 9px;
    font-weight: 650;
    text-align: left;
    cursor: pointer;
}
.relation-text-toggle::after,
.second-text-toggle::after { float: right; content: "⌄"; font-size: 12px; line-height: .8; }
.relation-text-toggle[aria-expanded="true"]::after,
.second-text-toggle[aria-expanded="true"]::after { content: "⌃"; }
.relation-text-toggle:hover,
.relation-text-toggle:focus-visible,
.second-text-toggle:hover,
.second-text-toggle:focus-visible { background: rgba(88, 228, 223, .08); outline: none; }
.branch-toggle {
    width: 100%;
    padding: 6px 11px 7px;
    color: var(--muted);
    border: 0;
    border-top: 1px solid var(--line);
    background: rgba(0, 0, 0, .11);
    font-size: 9px;
    text-align: left;
    cursor: pointer;
}
.branch-toggle::after { float: right; content: "+"; color: var(--chapter-color); font-size: 12px; }
.branch-toggle[aria-expanded="true"]::after { content: "−"; }
.branch-toggle:disabled { opacity: .38; cursor: default; }
.second-level-branch { margin: 0 9px 9px 13px; padding: 8px 0 0 10px; border-left: 1px solid currentColor; }
.second-level-branch.incoming { color: rgba(255, 158, 91, .55); }
.second-level-branch.outgoing { color: rgba(88, 228, 223, .55); }
.second-level-heading { display: flex; justify-content: space-between; margin-bottom: 6px; color: var(--muted); font-size: 8px; }
.second-level-heading strong { color: currentColor; }
.second-level-list { display: grid; gap: 4px; }
.second-rule-item {
    position: relative;
    border: 1px solid var(--line);
    border-radius: 7px;
    background: rgba(3, 12, 21, .68);
}
.second-rule-item::before { position: absolute; top: 50%; left: -11px; width: 10px; border-top: 1px solid currentColor; content: ""; }
.second-rule-button {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 6px;
    align-items: start;
    width: 100%;
    padding: 7px 8px;
    color: var(--text);
    border: 0;
    border-radius: 7px;
    background: transparent;
    text-align: left;
    cursor: pointer;
}
.second-rule-button span { color: var(--chapter-color); font-size: 8px; font-weight: 760; }
.second-rule-button strong {
    display: -webkit-box;
    min-width: 0;
    overflow: hidden;
    font-size: 9px;
    line-height: 1.45;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}
.second-rule-preview {
    display: -webkit-box;
    grid-column: 1 / -1;
    margin: 2px 0 0;
    max-height: calc(1.5em * 2);
    overflow: hidden;
    color: var(--muted);
    font-size: 8px;
    line-height: 1.5;
    white-space: pre-line;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}
.second-rule-item.text-expanded .second-rule-button strong,
.second-rule-item.text-expanded .second-rule-preview {
    display: block;
    max-height: none;
    overflow: visible;
    -webkit-line-clamp: unset;
}
.second-text-toggle { color: color-mix(in srgb, var(--chapter-color) 72%, #fff); background: rgba(255, 255, 255, .025); }
.second-rule-button small { grid-column: 1 / -1; color: var(--yellow); font-size: 7px; }
.second-rule-item:hover { border-color: var(--chapter-color); }
.second-rule-button:hover, .second-rule-button:focus-visible { background: rgba(255, 255, 255, .035); outline: none; }
.branch-empty { margin: 0; padding: 5px 0 7px; color: var(--muted); font-size: 9px; }
.relation-empty { display: grid; min-height: 150px; padding: 24px; place-items: center; align-content: center; color: var(--muted); text-align: center; }
.relation-empty span { color: currentColor; font-size: 30px; }
.relation-empty.incoming span { color: var(--orange); }
.relation-empty.outgoing span { color: var(--cyan); }
.relation-empty strong { margin-top: 5px; color: var(--text); font-size: 13px; }
.relation-empty p { margin: 4px 0 0; font-size: 10px; }

.current-column { display: flex; align-items: center; }
.current-rule-card {
    position: relative;
    width: 100%;
    overflow: hidden;
    padding: 24px;
    border: 1px solid color-mix(in srgb, var(--chapter-color) 62%, transparent);
    border-radius: 19px;
    background: linear-gradient(155deg, color-mix(in srgb, var(--chapter-color) 13%, #0d2237), #091727 70%);
    box-shadow: 0 24px 55px rgba(0, 0, 0, .38), 0 0 0 5px rgba(255, 255, 255, .018);
}
.current-rule-card::before { position: absolute; inset: 0 0 auto; height: 3px; background: var(--chapter-color); content: ""; }
.current-rule-card.is-changing { animation: current-card-in 210ms ease-out; }
.current-rule-chapter { display: flex; align-items: center; gap: 7px; color: var(--chapter-color); font-size: 9px; font-weight: 750; letter-spacing: .08em; }
.current-rule-chapter i { width: 7px; height: 7px; border-radius: 50%; background: currentColor; box-shadow: 0 0 0 4px color-mix(in srgb, var(--chapter-color) 12%, transparent); }
.current-rule-number { margin: 19px 0 2px; color: var(--muted); font-size: 12px; font-weight: 700; }
.current-rule-card h3 { margin: 0; font-size: clamp(22px, 2.1vw, 31px); line-height: 1.2; letter-spacing: -.02em; }
.current-rule-text { display: -webkit-box; margin: 15px 0 0; overflow: hidden; color: #b8cad9; font-size: 12px; line-height: 1.7; -webkit-box-orient: vertical; -webkit-line-clamp: 7; }
.current-rule-stats { display: grid; grid-template-columns: repeat(2, 1fr); margin: 20px 0 0; border-block: 1px solid var(--line); }
.current-rule-stats div { padding: 12px 0; }
.current-rule-stats div + div { padding-left: 15px; border-left: 1px solid var(--line); }
.current-rule-stats dt { font-size: 21px; font-weight: 780; }
.current-rule-stats dd { margin: 1px 0 0; color: var(--muted); font-size: 9px; }
.current-rule-children { margin-top: 15px; }
.current-rule-children > span { color: var(--muted); font-size: 8px; font-weight: 700; letter-spacing: .08em; }
.current-rule-children > div { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 6px; max-height: 76px; overflow-y: auto; }
.current-rule-children button { padding: 4px 7px; color: var(--chapter-color); border: 1px solid var(--line); border-radius: 6px; background: rgba(0, 0, 0, .16); font-size: 8px; cursor: pointer; }
.current-rule-children button:hover, .current-rule-children button:focus-visible { border-color: var(--chapter-color); }
.open-rule-link { display: flex; align-items: center; justify-content: space-between; margin-top: 19px; padding: 10px 12px; color: #06101d; border-radius: 9px; background: var(--chapter-color); font-size: 11px; font-weight: 760; }
.open-rule-link:hover, .open-rule-link:focus-visible { filter: brightness(1.08); }

@keyframes current-card-in {
    from { opacity: .35; transform: translateY(5px) scale(.992); }
    to { opacity: 1; transform: none; }
}

@media (max-width: 1160px) {
    .chapter-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .relation-diagram { grid-template-columns: minmax(225px, 1fr) minmax(280px, .9fr) minmax(225px, 1fr); gap: 38px; padding-inline: 16px; }
    .current-rule-card { padding: 20px; }
}

@media (max-width: 980px) {
    .knowledge-toolbar { grid-template-columns: 1fr auto; }
    .knowledge-search { grid-row: 2; grid-column: 1 / -1; }
    .chapter-main-rules { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 700px) {
    .relation-visit-strip { padding-block: 12px 10px; }
    .relation-workspace { width: min(100%, calc(100vw - 24px)); padding-bottom: 54px; }
    .knowledge-toolbar { grid-template-columns: 1fr; gap: 11px; padding: 16px; }
    .knowledge-toolbar > div:first-child { grid-column: auto; }
    .overview-button { width: 100%; }
    .search-input-wrap kbd { display: none; }
    .search-input-wrap input { padding-right: 13px; }
    .chapter-overview { padding: 15px; }
    .section-heading { display: block; }
    .section-heading h3 { font-size: 23px; }
    .section-heading p { margin-top: 5px; text-align: left; }
    .chapter-grid { grid-template-columns: 1fr; }
    .chapter-main-rules { grid-template-columns: 1fr; }
    .explorer-toolbar { align-items: flex-start; flex-direction: column; padding: 11px 15px; }
    .depth-toggle { width: 100%; justify-content: center; }
    .relation-key { gap: 9px 14px; padding: 9px 15px; }
    .relation-key span:last-child { flex-basis: 100%; }
    .current-rule-card h3 { font-size: 24px; }
    .current-rule-text { -webkit-line-clamp: 6; }
}

/* Phone landscape keeps the desktop relationship grammar: source → focus → target. */
@media (min-width: 640px) and (max-width: 980px) {
    .relation-diagram {
        grid-template-columns: minmax(0, 1fr) minmax(210px, .88fr) minmax(0, 1fr);
        gap: clamp(22px, 3vw, 34px);
        min-height: 430px;
        padding: 12px 10px;
    }
    .relation-lines { display: block; }
    .relation-column { overflow: hidden; }
    .column-heading { padding: 10px 10px 8px; }
    .column-heading h3 { font-size: 14px; }
    .column-heading strong { min-width: 29px; padding: 2px 6px; font-size: 11px; }
    .relation-list { max-height: 390px; padding: 7px; }
    .relation-group + .relation-group { margin-top: 8px; }
    .relation-group h4 { margin-bottom: 4px; font-size: 8px; }
    .relation-rule-button { gap: 6px; padding: 8px 7px 7px 9px; }
    .relation-rule-copy strong { font-size: 9px; -webkit-line-clamp: 2; }
    .relation-rule-preview { margin-top: 4px; font-size: 8px; -webkit-line-clamp: 2; }
    .relation-degree { width: 21px; height: 21px; margin-top: 4px; font-size: 8px; }
    .relation-text-toggle, .second-text-toggle, .branch-toggle { padding-inline: 8px; }
    .current-rule-card { max-width: none; margin: 0; padding: 16px 14px; border-radius: 15px; }
    .current-rule-number { margin-top: 12px; font-size: 10px; }
    .current-rule-card h3 { font-size: 20px; }
    .current-rule-text { margin-top: 10px; font-size: 10px; line-height: 1.55; -webkit-line-clamp: 4; }
    .current-rule-stats { margin-top: 12px; }
    .current-rule-stats div { padding: 8px 0; }
    .current-rule-stats dt { font-size: 17px; }
    .current-rule-children { margin-top: 10px; }
    .current-rule-children > div { max-height: 46px; }
    .open-rule-link { margin-top: 12px; padding: 8px 9px; font-size: 9px; }
}

/* Portrait becomes one connected vertical flow: focus → incoming → outgoing. */
@media (max-width: 639px) {
    .relation-diagram {
        grid-template-columns: 1fr;
        gap: 22px;
        min-height: 0;
        padding: 16px 4px;
        overflow: hidden;
        border: 1px solid rgba(157, 184, 211, .14);
        border-radius: 17px;
        background:
            linear-gradient(rgba(70, 120, 160, .035) 1px, transparent 1px),
            linear-gradient(90deg, rgba(70, 120, 160, .035) 1px, transparent 1px),
            radial-gradient(circle at 50% 48%, rgba(88, 228, 223, .11), transparent 24rem),
            #07131f;
        background-size: 42px 42px, 42px 42px, auto, auto;
    }
    .relation-lines { display: block; z-index: 1; }
    .connector { stroke-width: 1.8; }
    .current-column { order: 1; }
    .incoming-column { order: 2; }
    .outgoing-column { order: 3; }
    .relation-column, .current-column { margin-inline: 14px; }
    .relation-column { overflow: hidden; box-shadow: 0 14px 36px rgba(0, 0, 0, .2); }
    .relation-list { max-height: 360px; padding: 9px; }
    .incoming-column::before {
        display: block;
        padding: 9px;
        color: var(--orange);
        border-bottom: 1px solid rgba(255, 158, 91, .18);
        background: rgba(255, 158, 91, .07);
        font-size: 9px;
        font-weight: 750;
        letter-spacing: .04em;
        text-align: center;
        content: "以下规则引用当前规则  ↑";
    }
    .outgoing-column::before {
        display: block;
        padding: 9px;
        color: var(--cyan);
        border-bottom: 1px solid rgba(88, 228, 223, .18);
        background: rgba(88, 228, 223, .07);
        font-size: 9px;
        font-weight: 750;
        letter-spacing: .04em;
        text-align: center;
        content: "当前规则引用以下规则  ↓";
    }
    .current-column { padding-block: 8px; }
    .current-column::before {
        position: absolute;
        z-index: 4;
        top: -2px;
        left: 50%;
        padding: 4px 11px;
        color: #06101d;
        border-radius: 999px;
        background: var(--cyan);
        box-shadow: 0 0 0 5px #07131f;
        content: "当前规则";
        font-size: 9px;
        font-weight: 800;
        letter-spacing: .08em;
        transform: translateX(-50%);
    }
    .current-rule-card {
        max-width: none;
        margin: 0;
        padding: 24px 18px 20px;
        box-shadow: 0 24px 55px rgba(0, 0, 0, .4), 0 0 0 6px color-mix(in srgb, var(--chapter-color) 8%, transparent);
    }
}

@media (prefers-reduced-motion: reduce) {
    .chapter-card, .chapter-arrow, .current-rule-card.is-changing { animation: none; transition: none; }
    html { scroll-behavior: auto; }
}