:root {
    --ink: #2c241c;
    --ink-soft: #5c4c3c;
    --muted: #9a8874;
    --line: rgba(140, 112, 84, 0.22);
    --line-strong: rgba(108, 73, 47, 0.32);
    --xuan: #f6f0e6;
    --xuan-soft: #fbf7f0;
    --panel: rgba(252, 248, 241, 0.92);
    --chenxiang: #6b4530;
    --chenxiang-soft: #8a6548;
    --coffee: #a8866e;
    --coffee-deep: #8f6d55;
    --cinnabar: #b83a32;
    --cinnabar-deep: #962f28;
    --seal: rgba(184, 58, 50, 0.1);
    --glow: 0 12px 44px rgba(70, 45, 25, 0.1);
    --glow-sm: 0 6px 20px rgba(70, 45, 25, 0.08);
    --header-h: 92px;
    --radius: 12px;
    --radius-sm: 8px;
    --max: 1280px;
    --font-display: "Noto Serif SC", "Songti SC", "STSong", serif;
    --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
    --ease: cubic-bezier(0.22, 1, 0.36, 1);
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 24px;
    --space-6: 32px;
    --space-7: 48px;
    
    --fs-display: 1.375rem;   
    --fs-title: 1.125rem;     
    --fs-body: 0.9375rem;     
    --fs-label: 0.8125rem;    
    --fs-meta: 0.75rem;       
    --lh-tight: 1.35;
    --lh-body: 1.7;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}

body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: var(--ink);
    font-family: var(--font-body);
    font-size: var(--fs-body);
    line-height: var(--lh-body);
    background-color: #ebe2d4;
    background-image:
        radial-gradient(ellipse 120% 80% at 50% -10%, rgba(255, 250, 240, 0.75), transparent 55%),
        linear-gradient(180deg, rgba(246, 240, 230, 0.78), rgba(235, 226, 212, 0.9)),
        url("../image/background.webp");
    background-attachment: fixed;
    background-size: cover;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

body.nav-open { overflow: hidden; }

img {
    max-width: 100%;
    display: block;
}

a {
    color: var(--chenxiang-soft);
    text-decoration-thickness: 1px;
    text-underline-offset: 3px;
    transition: color 0.2s var(--ease);
}

a:hover { color: var(--cinnabar); }

:focus-visible {
    outline: 2px solid color-mix(in srgb, var(--cinnabar) 70%, white);
    outline-offset: 3px;
}

.visually-hidden {
    position: absolute !important;
    width: 1px; height: 1px;
    padding: 0; margin: -1px;
    overflow: hidden; clip: rect(0, 0, 0, 0);
    white-space: nowrap; border: 0;
}

.skip-link {
    position: absolute;
    left: 16px;
    top: -56px;
    z-index: 1200;
    padding: 10px 16px;
    border-radius: 999px;
    background: var(--cinnabar);
    color: #fff;
    text-decoration: none;
    font-size: 0.875rem;
    box-shadow: var(--glow-sm);
}

.skip-link:focus { top: 14px; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background:
        linear-gradient(180deg, #b3967c 0%, #a8866e 38%, #94725a 100%);
    border-bottom: 2px solid #6c492f;
    box-shadow:
        0 1px 0 rgba(255, 250, 243, 0.22) inset,
        0 10px 28px rgba(60, 40, 20, 0.18);
}

.site-header__inner {
    max-width: var(--max);
    margin: 0 auto;
    min-height: var(--header-h);
    padding: 0 20px;
    display: flex;
    align-items: center;
    gap: 14px;
}

.site-brand {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    text-decoration: none;
    filter: drop-shadow(0 1px 1px rgba(0, 0, 0, 0.12));
}

.site-brand img {
    height: 64px;
    width: auto;
    max-width: min(280px, 42vw);
    object-fit: contain;
}

.nav-toggle {
    display: none;
    margin-left: auto;
    width: 44px;
    height: 44px;
    border: 1px solid rgba(255, 255, 255, 0.35);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.08);
    cursor: pointer;
    padding: 11px;
    flex-direction: column;
    justify-content: space-between;
}

.nav-toggle span {
    display: block;
    height: 2px;
    border-radius: 2px;
    background: #fffaf3;
}

.product-nav {
    display: flex;
    flex: 1;
    justify-content: flex-end;
    flex-wrap: wrap;
    gap: 2px;
}

.product-nav__link {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
    min-width: 66px;
    padding: 7px 9px;
    color: rgba(255, 250, 243, 0.92);
    text-decoration: none;
    font-family: var(--font-display);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    border-radius: 10px;
    transition: background-color 0.22s var(--ease), color 0.22s var(--ease), transform 0.22s var(--ease);
}

.product-nav__link:hover {
    background: rgba(253, 252, 243, 0.96);
    color: var(--chenxiang);
}

.product-nav__link.is-current {
    background: rgba(253, 252, 243, 0.18);
    box-shadow: inset 0 -2px 0 var(--cinnabar);
}

.product-nav__icon {
    width: 34px;
    height: 34px;
    object-fit: contain;
    filter: drop-shadow(0 1px 1px rgba(0, 0, 0, 0.15));
}

.hero-search {
    position: relative;
    z-index: 50;
    min-height: clamp(250px, 34vw, 360px);
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding: 28px 20px 36px;
    background-image: url("../image/home_banner.webp");
    background-size: cover;
    background-position: center top;
    background-repeat: no-repeat;
    overflow: visible;
}

.hero-search::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        linear-gradient(180deg, transparent 35%, rgba(40, 28, 18, 0.18) 72%, rgba(40, 28, 18, 0.38) 100%);
    pointer-events: none;
}

.hero-search__stage {
    position: relative;
    z-index: 1;
    width: min(700px, 100%);
    text-align: center;
}

.search-bar {
    display: flex;
    align-items: stretch;
    position: relative;
    background: #fbf7f0;
    border: 1px solid rgba(108, 73, 47, 0.28);
    border-radius: 4px;
    overflow: visible;
    box-shadow: 0 8px 24px rgba(40, 28, 18, 0.18);
}

.search-bar__select,
.search-bar__input,
.search-bar__submit {
    border: 0;
    font: inherit;
}

.search-bar__select {
    flex: 0 0 auto;
    min-width: 92px;
    padding: 0 16px;
    background: transparent;
    color: var(--ink-soft);
    border-right: 1px solid var(--line);
    cursor: pointer;
    font-family: var(--font-display);
    letter-spacing: 0.08em;
}

.search-bar__input {
    flex: 1;
    min-width: 0;
    padding: 15px 36px 15px 18px;
    background: transparent;
    color: var(--ink);
}

.search-bar__input::placeholder {
    color: var(--muted);
}

.search-bar__submit {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-width: 96px;
    margin: 4px;
    padding: 0 18px;
    border-radius: 3px;
    background: var(--cinnabar);
    color: #fff;
    cursor: pointer;
    font-family: var(--font-display);
    letter-spacing: 0.06em;
    box-shadow: none;
    transition: background-color 0.15s ease;
}

.search-bar__submit:hover {
    background: #962f28;
}

.search-bar__submit:active { background: #7e2721; }

.hero-search__meta {
    margin: 12px 0 0;
    font-size: 0.78rem;
    color: rgba(255, 250, 243, 0.9);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
    letter-spacing: 0.04em;
}

.paper-frame {
    position: relative;
    background:
        linear-gradient(165deg, rgba(255, 252, 247, 0.97), rgba(246, 240, 230, 0.94));
    border: 1px solid var(--line-strong);
    border-radius: var(--radius);
    box-shadow: var(--glow-sm);
    padding: 26px 24px 22px;
    overflow: hidden;
}

.paper-frame::before {
    content: "";
    position: absolute;
    inset: 7px;
    border: 1px solid color-mix(in srgb, var(--coffee) 28%, transparent);
    border-radius: calc(var(--radius) - 4px);
    pointer-events: none;
}

.paper-frame::after {
    display: none;
}

.frame-title {
    position: relative;
    z-index: 1;
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 8px 14px;
    margin-bottom: 20px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--line);
}

.frame-title__mark {
    width: 3px;
    height: 1.15em;
    border-radius: 2px;
    background: linear-gradient(180deg, var(--cinnabar), color-mix(in srgb, var(--cinnabar) 40%, var(--chenxiang)));
    flex-shrink: 0;
}

.frame-title h2,
.frame-title .frame-title__h1 {
    margin: 0;
    font-family: var(--font-display);
    font-size: var(--fs-display);
    font-weight: 600;
    letter-spacing: 0.06em;
    color: var(--chenxiang);
    line-height: var(--lh-tight);
}

.frame-title p {
    margin: 0;
    font-size: var(--fs-meta);
    color: var(--muted);
    letter-spacing: 0;
}

.section-title {
    margin: 0 0 16px;
    font-family: var(--font-display);
    font-size: var(--fs-display);
    font-weight: 600;
    letter-spacing: 0.06em;
    color: var(--chenxiang);
    line-height: var(--lh-tight);
}

.page-shell {
    position: relative;
    z-index: 1;
    flex: 1 0 auto;
    width: 100%;
    max-width: var(--max);
    margin: 0 auto;
    padding: 28px 24px 64px;
}

.layout-home {
    display: grid;
    grid-template-columns: 240px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
}

.home-main {
    display: grid;
    gap: 24px;
    min-width: 0;
}

.layout-list {
    display: grid;
    grid-template-columns: 240px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
}

.layout-detail {
    display: grid;
    grid-template-columns: 240px 300px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
}

.breadcrumb {
    margin: 0 0 20px;
    font-size: var(--fs-label);
    color: var(--muted);
}

.breadcrumb ol {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 6px;
}

.breadcrumb li {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: var(--font-display);
}

.breadcrumb li:not(:last-child)::after {
    content: "›";
    color: var(--line-strong);
    margin-left: 2px;
}

.breadcrumb a {
    color: var(--chenxiang-soft);
    text-decoration: none;
}

.breadcrumb a:hover { color: var(--cinnabar); }

.breadcrumb [aria-current="page"] { color: var(--ink-soft); }

.layout-home {
    display: grid;
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.home-main {
    display: grid;
    gap: 18px;
    min-width: 0;
}

.layout-list {
    display: grid;
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.layout-detail {
    display: grid;
    grid-template-columns: 220px 280px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.surname-panel {
    position: sticky;
    top: calc(var(--header-h) + 12px);
    align-self: start;
    margin: 0;
    max-height: min(640px, calc(100vh - var(--header-h) - 48px));
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transform: none !important;
    opacity: 1 !important;
    z-index: 1;
}

.hot-surname-scroll {
    position: relative;
    z-index: 1;
    flex: 1 1 auto;
    min-height: 0;
    overflow-x: hidden;
    overflow-y: auto;
    padding: 2px;
}

.surname-chip-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
}

.surname-chip {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 6px 4px;
    text-decoration: none;
    color: var(--ink);
    font-family: var(--font-display);
    font-size: 1.02rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    background: color-mix(in srgb, var(--xuan) 80%, white);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.surname-chip:hover {
    color: var(--cinnabar);
    border-color: color-mix(in srgb, var(--cinnabar) 45%, var(--line));
    background: var(--seal);
}

.hot-surname-scroll::-webkit-scrollbar,
.shelf-rail::-webkit-scrollbar,
.cover-rail::-webkit-scrollbar {
    width: 5px;
    height: 5px;
}

.hot-surname-scroll::-webkit-scrollbar-thumb,
.shelf-rail::-webkit-scrollbar-thumb,
.cover-rail::-webkit-scrollbar-thumb {
    background: color-mix(in srgb, var(--coffee) 70%, transparent);
    border-radius: 999px;
}

.shelf-rail,
.cover-rail {
    position: relative;
    z-index: 1;
    display: grid;
    grid-auto-flow: column;
    gap: 16px;
    overflow-x: auto;
    padding: 8px 4px 14px;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
}

.shelf-rail { grid-auto-columns: 120px; }
.cover-rail { grid-auto-columns: 172px; gap: 20px; }

.shelf-book,
.cover-card {
    scroll-snap-align: start;
    display: flex;
    flex-direction: column;
    gap: 10px;
    text-decoration: none;
    color: inherit;
    min-width: 0;
}

.shelf-book__cover,
.cover-card__frame {
    display: block;
    margin: 0 auto;
    background:
        linear-gradient(145deg, #fffdf8, #efe6d8);
    border: 1px solid var(--line-strong);
    border-radius: 4px;
    box-shadow:
        0 1px 0 rgba(255, 255, 255, 0.7) inset,
        0 10px 24px rgba(70, 45, 25, 0.12);
    overflow: hidden;
    transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.25s ease;
}

.shelf-book__cover {
    width: 110px;
    height: 148px;
}

.cover-card__frame {
    width: 168px;
    height: 224px;
    margin-bottom: 2px;
}

.shelf-book__cover img,
.cover-card__frame img {
    width: 100% !important;
    height: 100% !important;
    max-width: none;
    object-fit: cover;
    object-position: center top;
}

.shelf-book:hover .shelf-book__cover,
.cover-card:hover .cover-card__frame {
    transform: translateY(-8px);
    border-color: color-mix(in srgb, var(--chenxiang) 45%, var(--line));
    box-shadow: 0 18px 36px rgba(70, 45, 25, 0.16);
}

.shelf-book__name,
.cover-card h3 {
    margin: 0;
    text-align: center;
    font-family: var(--font-display);
    font-size: 0.86rem;
    font-weight: 600;
    line-height: 1.4;
    color: var(--ink-soft);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.cover-card h3 { font-size: 0.94rem; color: var(--ink); }

.shelf-book:hover .shelf-book__name,
.cover-card:hover h3 { color: var(--cinnabar); }

.alpha-bar {
    position: relative;
    z-index: 1;
    display: flex;
    flex-wrap: nowrap;
    align-items: center;
    gap: 4px;
    margin-bottom: 18px;
    padding: 8px 10px;
    background: color-mix(in srgb, var(--xuan) 55%, transparent);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    overflow-x: auto;
}

.letter-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 1 1 0;
    min-width: 28px;
    width: auto;
    height: 32px;
    border: 1px solid transparent;
    border-radius: 8px;
    background: transparent;
    color: var(--ink-soft);
    font-family: var(--font-display);
    font-size: 0.86rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.letter-link:hover {
    background: color-mix(in srgb, var(--coffee) 16%, white);
    border-color: var(--line);
}

.letter-link.is-active {
    background: var(--chenxiang);
    color: #fffaf3;
    transform: translateY(-1px);
    box-shadow: var(--glow-sm);
}

.family-list {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(92px, 1fr));
    gap: 12px;
}

.family-member {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 12px 8px;
    text-decoration: none;
    color: var(--ink);
    background: color-mix(in srgb, var(--xuan) 70%, white);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    transition: border-color 0.2s var(--ease), transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.family-member img {
    width: 56px !important;
    height: 56px !important;
    object-fit: cover;
    border-radius: 50%;
    border: 1px solid var(--line-strong);
    box-shadow: var(--glow-sm);
}

.family-member span {
    font-family: var(--font-display);
    font-size: 1rem;
    letter-spacing: 0.04em;
}

.family-member:hover {
    border-color: color-mix(in srgb, var(--cinnabar) 40%, var(--line));
    color: var(--cinnabar);
}

.book-list-meta {
    position: relative;
    z-index: 1;
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--line);
}

.book-list-meta .section-title { margin: 0; }

.result-count {
    font-size: 0.86rem;
    color: var(--muted);
}

.result-count strong {
    color: var(--cinnabar);
    font-family: var(--font-display);
    font-weight: 600;
}

.book-list {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 18px;
}

.book-item {
    display: grid;
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 16px;
    padding: 18px;
    background: color-mix(in srgb, var(--xuan-soft) 88%, white);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: border-color 0.22s var(--ease), box-shadow 0.22s var(--ease), transform 0.22s var(--ease), background-color 0.22s var(--ease);
}

.book-item:hover {
    border-color: color-mix(in srgb, var(--chenxiang) 40%, var(--line));
    background: #fffdf9;
    box-shadow: var(--glow);
    transform: translateY(-3px);
}

.book-item img {
    width: 100% !important;
    height: 100% !important;
    max-width: none;
    object-fit: contain;
    object-position: center center;
    border-radius: 0;
    border: 0;
    background: transparent;
    box-shadow: none;
}

.book-info h2,
.book-info h3 {
    margin: 0 0 12px;
    font-family: var(--font-display);
    font-size: var(--fs-title);
    font-weight: 600;
    letter-spacing: 0.04em;
    line-height: var(--lh-tight);
    color: var(--ink);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.book-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.book-meta__tag {
    display: inline-flex;
    align-items: center;
    max-width: 100%;
    padding: 4px 10px;
    border-radius: 999px;
    background: color-mix(in srgb, var(--coffee) 12%, white);
    border: 1px solid var(--line);
    color: var(--ink-soft);
    font-size: var(--fs-meta);
    letter-spacing: 0.04em;
    line-height: 1.4;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.book-info p {
    margin: 0 0 4px;
    font-size: 0.85rem;
    color: var(--muted);
}

.pagination {
    position: relative;
    z-index: 1;
    margin-top: 24px;
    display: flex;
    justify-content: center;
}

.detail-cover {
    position: relative;
    z-index: 1;
    width: min(100%, 260px);
    margin: 0 auto 22px;
    border-radius: 0;
    border: 0;
    background: transparent;
    box-shadow: none;
    overflow: visible;
}

.detail-cover img {
    width: 100% !important;
    height: 100% !important;
    aspect-ratio: auto;
    object-fit: contain;
    object-position: center center;
}

.detail-meta {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 12px;
}

.info-block {
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    background: color-mix(in srgb, var(--xuan) 55%, white);
    border: 1px solid var(--line);
}

.info-label {
    margin: 0 0 6px;
    font-size: var(--fs-meta);
    letter-spacing: 0.04em;
    color: var(--muted);
    font-weight: 500;
}

.info-value {
    margin: 0;
    font-family: var(--font-display);
    font-size: var(--fs-title);
    color: var(--ink);
    line-height: 1.45;
    word-break: break-word;
}

.volume-list {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(148px, 1fr));
    gap: 12px;
}

.volume-item .volume-number {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 56px;
    padding: 14px 16px;
    text-align: center;
    background: color-mix(in srgb, var(--xuan-soft) 85%, white);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    color: var(--ink);
    font-family: var(--font-display);
    font-size: 0.98rem;
    letter-spacing: 0.06em;
    cursor: pointer;
    transition: background-color 0.22s var(--ease), color 0.22s var(--ease), border-color 0.22s var(--ease), transform 0.22s var(--ease), box-shadow 0.22s var(--ease);
}

.volume-item .volume-number:hover {
    background: var(--chenxiang);
    border-color: var(--chenxiang);
    color: #fffaf3;
}

.empty-state,
.loading-text,
.empty-hint,
.no-results-message {
    position: relative;
    z-index: 1;
    margin: 28px 0;
    text-align: center;
    color: var(--muted);
}

.empty-state { padding: 40px 16px; }

.empty-state__title {
    margin: 0 0 8px;
    font-family: var(--font-display);
    font-size: 1.12rem;
    color: var(--chenxiang);
    letter-spacing: 0.04em;
}

.empty-state__desc {
    margin: 0 0 18px;
    font-size: 0.9rem;
}

.empty-state__cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 40px;
    padding: 0 18px;
    border-radius: 2px;
    background: var(--chenxiang);
    color: #fffaf3 !important;
    text-decoration: none;
    font-family: var(--font-display);
    letter-spacing: 0.04em;
    box-shadow: none;
}

.empty-state__cta:hover { background: var(--cinnabar); }

.site-footer {
    margin-top: auto;
    width: 100%;
    background: transparent;
    color: rgba(255, 250, 243, 0.9);
    padding: 0;
    border: 0;
}

.site-footer__inner {
    max-width: var(--max);
    margin: 0 auto;
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) auto minmax(0, 1.1fr);
    gap: 28px 40px;
    align-items: end;
}

.site-footer__social {
    display: flex;
    gap: 20px;
}

.site-footer__social figure { margin: 0; text-align: center; }

.site-footer__social img {
    width: 72px;
    height: 72px;
    object-fit: cover;
    margin: 0 auto;
    background: #fffdf9;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.28);
}

.site-footer__social figcaption {
    margin-top: 8px;
    font-size: 0.72rem;
    opacity: 0.8;
}

.site-footer__info {
    min-width: 0;
}

.site-footer__info p {
    margin: 0;
    font-size: 0.78rem;
    line-height: 1.7;
}

.site-footer a { color: #fffaf3; }

.site-footer__links {
    display: inline-flex;
    gap: 0;
}

@media (max-width: 1100px) {
    .layout-detail {
        grid-template-columns: 220px minmax(0, 1fr);
    }

    .layout-detail .detail-card-panel {
        grid-column: 1 / -1;
        order: 2;
        display: grid;
        grid-template-columns: 200px minmax(0, 1fr);
        gap: 20px;
        align-items: start;
    }

    .layout-detail .volume-panel {
        grid-column: 1 / -1;
        order: 3;
    }
}

@media (max-width: 900px) {
    .nav-toggle { display: flex; }

    .product-nav {
        position: fixed;
        inset: var(--header-h) 0 auto 0;
        max-height: calc(100vh - var(--header-h));
        overflow: auto;
        display: none;
        flex-direction: column;
        background: color-mix(in srgb, var(--coffee-deep) 96%, black);
        padding: 10px;
        z-index: 999;
        border-bottom: 1px solid var(--chenxiang);
    }

    .product-nav.is-open { display: flex; }

    .product-nav__link {
        flex-direction: row;
        justify-content: flex-start;
        gap: 12px;
        min-height: 48px;
        padding: 10px 14px;
        font-size: 0.95rem;
        border-radius: 8px;
    }

    .layout-home,
    .layout-list,
    .layout-detail { grid-template-columns: 1fr; }

    .surname-panel { position: static; max-height: none; }
    .hot-surname-scroll { max-height: 200px; }
    .surname-chip-list { grid-template-columns: repeat(6, 1fr); }

    .layout-detail .detail-card-panel { grid-template-columns: 1fr; }

    .page-shell { padding: 20px 16px 48px; }

    .search-bar {
        flex-wrap: wrap;
        border-radius: 16px;
    }

    .search-bar__select {
        width: 100%;
        border-right: 0;
        border-bottom: 1px solid var(--line);
        padding: 12px 16px;
        text-align: left;
    }

    .search-bar__submit {
        width: calc(100% - 10px);
        min-height: 44px;
        margin: 5px;
    }

    .letter-link {
        flex: 1 1 0;
        min-width: 28px;
        width: auto;
        height: 36px;
    }

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

@media (max-width: 480px) {
    .page-shell { padding: 14px 12px 40px; }
    .surname-chip-list { grid-template-columns: repeat(4, 1fr); }

    .book-item { grid-template-columns: auto minmax(0, 1fr); }
    .book-item img {
        width: 100% !important;
        height: 100% !important;
    }

    .site-footer__inner {
        grid-template-columns: 1fr;
        text-align: center;
        justify-items: center;
    }

    .site-footer__links { justify-content: center; }
}