/* =========================================================
   Notebook 笔记本风格主题
   淡蓝小清新 + 书本 3D 翻页
   ========================================================= */

:root {
    --nb-blue: #7ec8e3;
    --nb-blue-deep: #4aa3c9;
    --nb-blue-light: #e8f6fb;
    --nb-blue-bg: #dff0f7;
    --nb-ink: #3a4a55;
    --nb-ink-light: #6b7f8c;
    --nb-paper: #fffdf7;
    --nb-paper-edge: #f5efe0;
    --nb-shadow: rgba(74, 163, 201, 0.25);
    --nb-font: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
}

body {
    font-family: var(--nb-font);
    color: var(--nb-ink);
    background: linear-gradient(160deg, #dff0f7 0%, #c3e4f2 40%, #eaf7fb 100%);
    min-height: 100vh;
    overflow-x: hidden;
}

a {
    color: var(--nb-blue-deep);
    text-decoration: none;
}

.nb-stage {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 30px 20px 40px;
    position: relative;
    box-sizing: border-box;
}

/* 背景装饰云朵 */
.nb-stage::before,
.nb-stage::after {
    content: "";
    position: fixed;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    filter: blur(2px);
    z-index: 0;
    pointer-events: none;
}
.nb-stage::before {
    width: 260px;
    height: 90px;
    top: 8%;
    left: 6%;
    box-shadow: 60px 30px 0 20px rgba(255,255,255,0.35);
}
.nb-stage::after {
    width: 200px;
    height: 70px;
    bottom: 12%;
    right: 8%;
    box-shadow: -40px 20px 0 15px rgba(255,255,255,0.3);
}

/* =========================================================
   封面
   ========================================================= */
.nb-cover {
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 30px 0;
    perspective: 2000px;
    z-index: 1;
    flex: 1 1 0;
    min-height: 0;
    box-sizing: border-box;
}

.nb-cover-book {
    position: relative;
    width: min(560px, 90vw);
    height: min(720px, 100%);
    border-radius: 8px 18px 18px 8px;
    overflow: hidden;
    cursor: pointer;
    box-shadow:
        0 30px 60px var(--nb-shadow),
        0 10px 20px rgba(0,0,0,0.08),
        inset -12px 0 24px rgba(0,0,0,0.12);
    transform-style: preserve-3d;
    transition: transform 0.6s ease, box-shadow 0.6s ease;
    background: var(--nb-blue-deep);
}

.nb-cover-book:hover {
    transform: translateY(-6px) rotateY(-4deg);
    box-shadow:
        0 40px 70px var(--nb-shadow),
        0 15px 25px rgba(0,0,0,0.1),
        inset -12px 0 24px rgba(0,0,0,0.12);
}

/* 封面左侧书脊 */
.nb-cover-book::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 26px;
    background: linear-gradient(90deg, rgba(0,0,0,0.18), rgba(0,0,0,0.05) 60%, transparent);
    z-index: 3;
}

.nb-cover-img {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    transition: transform 0.6s ease;
}

.nb-cover-book:hover .nb-cover-img {
    transform: scale(1.04);
}

/* 封面文字遮罩 */
.nb-cover-text {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
    background: rgba(74, 163, 201, 0.25);
    text-shadow: 0 2px 12px rgba(0,0,0,0.35);
    padding: 20px;
    z-index: 2;
}

.nb-cover-title {
    font-size: clamp(40px, 8vw, 72px);
    font-weight: 700;
    letter-spacing: 12px;
    margin-bottom: 16px;
    font-family: "Kaiti SC", "STKaiti", "KaiTi", serif;
}

.nb-cover-subtitle {
    font-size: clamp(15px, 2.5vw, 20px);
    letter-spacing: 4px;
    opacity: 0.95;
    font-family: "Kaiti SC", "STKaiti", "KaiTi", serif;
}

.nb-cover-hint {
    position: absolute;
    bottom: 26px;
    left: 50%;
    transform: translateX(-50%);
    color: #fff;
    font-size: 14px;
    letter-spacing: 3px;
    background: rgba(0,0,0,0.25);
    padding: 8px 20px;
    border-radius: 30px;
    z-index: 3;
    animation: nbPulse 2s ease-in-out infinite;
}

@keyframes nbPulse {
    0%, 100% { opacity: 0.7; }
    50% { opacity: 1; }
}

/* =========================================================
   书本阅读区
   ========================================================= */
.nb-book-wrap {
    width: 100%;
    max-width: 1100px;
    display: flex;
    flex-direction: column;
    align-items: center;
    z-index: 1;
    animation: nbFadeIn 0.6s ease;
}

@keyframes nbFadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.nb-book {
    position: relative;
    width: min(1000px, 96vw);
    height: min(620px, 70vh);
    perspective: 2600px;
    display: flex;
}

/* 书本主体（两页容器） */
.nb-book::before {
    content: "";
    position: absolute;
    inset: -14px;
    background: linear-gradient(145deg, #fdf3e3, #f3e6cf);
    border-radius: 10px 22px 22px 10px;
    box-shadow:
        0 30px 60px rgba(74, 163, 201, 0.3),
        0 8px 16px rgba(0,0,0,0.12);
    z-index: 0;
}

/* 书页 */
.nb-page {
    position: relative;
    width: 50%;
    height: 100%;
    z-index: 1;
    overflow: hidden;
    background: var(--nb-paper);
}

.nb-page-left {
    border-radius: 10px 0 0 10px;
    box-shadow: inset -18px 0 30px -18px rgba(0,0,0,0.18);
}

.nb-page-right {
    border-radius: 0 10px 10px 0;
    box-shadow: inset 18px 0 30px -18px rgba(0,0,0,0.18);
}

.nb-page-inner {
    position: absolute;
    inset: 0;
    padding: 34px 30px;
    overflow: hidden;
}

/* 左页图片区 */
.nb-left-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    gap: 14px;
    overflow-y: auto;
    padding-right: 35px;
    scrollbar-width: thin;
    scrollbar-color: var(--nb-blue) transparent;
}
.nb-left-inner::-webkit-scrollbar { width: 6px; }
.nb-left-inner::-webkit-scrollbar-thumb { background: var(--nb-blue); border-radius: 6px; }
.nb-left-inner::-webkit-scrollbar-track { background: transparent; }

/* 单图：尽量铺满但保留四周留白，空间充足时居中，超出可滚动 */
.nb-left-inner .nb-img-single {
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    object-fit: contain;
    border-radius: 6px;
    box-shadow: 0 6px 16px rgba(0,0,0,0.15);
    flex: 0 0 auto;
    margin: auto;
}

/* 多图网格：按可用高度排布，空间充足时居中 */
.nb-left-inner .nb-img-grid {
    display: grid;
    gap: 10px;
    width: 100%;
    height: 100%;
    min-height: 0;
    align-content: center;
    flex: 1 1 auto;
    margin: auto;
}

.nb-left-inner .nb-img-item {
    width: 100%;
    height: 100%;
    min-height: 0;
    object-fit: cover;
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.12);
}

/* 左页媒体(视频/音频)区 */
.nb-left-inner .nb-media {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    flex: 0 0 auto;
}
.nb-left-inner .nb-media-video {
    width: 100%;
    max-width: 100%;
}
.nb-left-inner .nb-media-video video {
    width: 100%;
    max-height: 46vh;
    border-radius: 8px;
    background: #000;
    box-shadow: 0 6px 16px rgba(0,0,0,0.15);
}
.nb-left-inner .nb-media-audio {
    background: #eaf6fb;
    border: 1px solid rgba(74, 163, 201, 0.35);
    border-radius: 10px;
    padding: 12px 14px;
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    width: 100%;
}
.nb-left-inner .nb-media-audio audio {
    width: 100%;
    max-width: 260px;
    height: 40px;
}
.nb-left-inner .nb-media-audio-icon {
    font-size: 22px;
}
.nb-left-inner .nb-media-title {
    width: 100%;
    text-align: center;
    font-size: 12px;
    color: var(--nb-ink-light);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* 右页文字区 */
.nb-right-inner {
    display: flex;
    flex-direction: column;
}

.nb-post-title {
    font-size: 26px;
    font-weight: 700;
    color: var(--nb-blue-deep);
    margin-bottom: 8px;
    line-height: 1.3;
    font-family: "Kaiti SC", "STKaiti", "KaiTi", serif;
}

.nb-post-date {
    font-size: 13px;
    color: var(--nb-ink-light);
    margin-bottom: 14px;
    padding-bottom: 12px;
    border-bottom: 1px dashed rgba(74, 163, 201, 0.4);
    letter-spacing: 1px;
}

.nb-post-content {
    flex: 1;
    overflow: hidden;
    font-size: 16px;
    line-height: 1.9;
    color: var(--nb-ink);
}

.nb-post-content p {
    margin-bottom: 1em;
}

.nb-post-content h1, .nb-post-content h2, .nb-post-content h3,
.nb-post-content h4, .nb-post-content h5, .nb-post-content h6 {
    margin: 0.8em 0 0.4em;
    color: var(--nb-blue-deep);
    line-height: 1.4;
}

.nb-post-content img {
    max-width: 100%;
    height: auto;
    border-radius: 6px;
}

.nb-post-content blockquote {
    border-left: 4px solid var(--nb-blue);
    background: var(--nb-blue-light);
    padding: 10px 16px;
    margin: 1em 0;
    border-radius: 0 6px 6px 0;
    color: var(--nb-ink-light);
}

.nb-post-content pre {
    background: #2d3a44;
    color: #e8f6fb;
    padding: 14px;
    border-radius: 6px;
    overflow-x: auto;
    margin: 1em 0;
    font-size: 14px;
}

.nb-post-content code {
    background: var(--nb-blue-light);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.9em;
}

.nb-post-content pre code {
    background: transparent;
    padding: 0;
}

.nb-post-content ul, .nb-post-content ol {
    padding-left: 1.6em;
    margin: 0.6em 0;
}

/* 分页指示（右页底部） */
.nb-page-num {
    text-align: right;
    font-size: 12px;
    color: var(--nb-ink-light);
    padding-top: 8px;
    border-top: 1px dashed rgba(74, 163, 201, 0.3);
    margin-top: 8px;
    font-family: Georgia, serif;
}

/* 空状态 */
.nb-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--nb-ink-light);
    text-align: center;
    gap: 12px;
}
.nb-empty .nb-empty-icon { font-size: 60px; }

/* 翻页动画层 */
.nb-flip {
    position: absolute;
    top: 0;
    height: 100%;
    width: 50%;
    z-index: 5;
    transform-origin: left center;
    transform-style: preserve-3d;
    backface-visibility: hidden;
    pointer-events: none;
    display: none;
}
.nb-flip.active,
.nb-flip.prev {
    display: block;
}
.nb-flip.active {
    animation: nbFlipNext 0.7s ease forwards;
}
.nb-flip.prev {
    animation: nbFlipPrev 0.7s ease forwards;
}

@keyframes nbFlipNext {
    0%   { transform: rotateY(0deg); }
    100% { transform: rotateY(-180deg); }
}
@keyframes nbFlipPrev {
    0%   { transform: rotateY(-180deg); }
    100% { transform: rotateY(0deg); }
}

/* =========================================================
   控制栏
   ========================================================= */
.nb-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 14px;
    margin-top: 26px;
    flex-wrap: wrap;
    z-index: 1;
}

.nb-btn {
    background: linear-gradient(135deg, var(--nb-blue), var(--nb-blue-deep));
    color: #fff;
    border: none;
    padding: 10px 22px;
    border-radius: 30px;
    font-size: 15px;
    cursor: pointer;
    font-family: var(--nb-font);
    box-shadow: 0 4px 12px var(--nb-shadow);
    transition: all 0.25s ease;
    letter-spacing: 1px;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    line-height: 1.4;
}
.nb-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 18px var(--nb-shadow);
    filter: brightness(1.05);
}
.nb-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

/* 快速写文章按钮（仅登录显示，作为链接） */
.nb-btn-write {
    background: linear-gradient(135deg, #7ed6a5, #4aa37a);
    box-shadow: 0 4px 12px rgba(74, 163, 122, 0.4);
}

.nb-pageinfo {
    font-size: 15px;
    color: var(--nb-ink);
    background: rgba(255,255,255,0.7);
    padding: 8px 18px;
    border-radius: 20px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    min-width: 120px;
    text-align: center;
}

/* 快速跳页输入框（页码右侧） */
.nb-pagejump {
    width: 64px;
    padding: 8px 10px;
    border: 1px solid rgba(74, 163, 201, 0.35);
    border-radius: 20px;
    font-size: 14px;
    text-align: center;
    color: var(--nb-ink);
    background: rgba(255,255,255,0.7);
    font-family: var(--nb-font);
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    -moz-appearance: textfield;
    appearance: textfield;
}
.nb-pagejump::-webkit-outer-spin-button,
.nb-pagejump::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.nb-pagejump:focus {
    border-color: var(--nb-blue-deep);
    box-shadow: 0 0 0 3px rgba(74, 163, 201, 0.15);
}

/* =========================================================
   留言板按钮
   ========================================================= */
.nb-btn-guest {
    background: linear-gradient(135deg, #ffd6a5, #ffb27a);
    box-shadow: 0 4px 12px rgba(255, 178, 122, 0.4);
}

/* =========================================================
   留言板区域
   ========================================================= */
.nb-guestbook {
    width: min(1000px, 96vw);
    margin-top: 24px;
    background: rgba(255, 255, 255, 0.85);
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(74, 163, 201, 0.2);
    padding: 24px 28px;
    z-index: 1;
    backdrop-filter: blur(6px);
    animation: nbFadeIn 0.4s ease;
}

.nb-guestbook-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 18px;
    padding-bottom: 14px;
    border-bottom: 2px solid var(--nb-blue-light);
}
.nb-guestbook-head h3 {
    font-size: 20px;
    color: var(--nb-blue-deep);
    font-family: "Kaiti SC", "STKaiti", "KaiTi", serif;
}
.nb-btn-close {
    background: #e2e8ee;
    color: var(--nb-ink);
    box-shadow: none;
    padding: 6px 16px;
    font-size: 13px;
}

.nb-guestbook-list {
    max-height: 320px;
    overflow-y: auto;
    margin-bottom: 20px;
    padding-right: 6px;
}
.nb-guestbook-list::-webkit-scrollbar { width: 6px; }
.nb-guestbook-list::-webkit-scrollbar-thumb { background: var(--nb-blue); border-radius: 6px; }

.nb-guest-item {
    background: var(--nb-blue-light);
    padding: 12px 16px;
    margin-bottom: 10px;
    border-left: 4px solid var(--nb-blue);
}
.nb-guest-item .nb-guest-meta {
    font-size: 13px;
    color: var(--nb-blue-deep);
    margin-bottom: 6px;
    font-weight: 600;
}
.nb-guest-item .nb-guest-meta .nb-guest-time {
    font-weight: normal;
    color: var(--nb-ink-light);
    margin-left: 10px;
    font-size: 12px;
}
.nb-guest-item .nb-guest-text {
    font-size: 15px;
    line-height: 1.7;
    color: var(--nb-ink);
    word-break: break-word;
}
.nb-guest-item .nb-guest-foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 8px;
}
.nb-guest-item .nb-guest-time {
    font-size: 12px;
    color: var(--nb-ink-light);
}
.nb-guest-reply-btn {
    border: none;
    background: none;
    cursor: pointer;
    font-size: 12px;
    color: var(--nb-blue-deep);
    padding: 2px 4px;
    font-family: var(--nb-font);
}
.nb-guest-reply-btn:hover {
    text-decoration: underline;
    color: var(--nb-blue);
}

/* 嵌套回复（缩进显示在父留言下方） */
.nb-guest-replies {
    margin-top: 10px;
    padding-left: 14px;
    border-left: 2px solid rgba(74, 163, 201, 0.25);
}
.nb-guest-reply {
    background: rgba(255, 255, 255, 0.7);
    padding: 10px 14px;
    margin-bottom: 8px;
    border-radius: 8px;
}
.nb-guest-reply .nb-guest-meta {
    font-size: 13px;
    color: var(--nb-blue-deep);
    font-weight: 600;
}
.nb-guest-reply .nb-guest-text {
    font-size: 14px;
    line-height: 1.7;
    color: var(--nb-ink);
    word-break: break-word;
    margin-top: 4px;
}
.nb-guest-reply .nb-guest-foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 6px;
}

/* 正在回复提示条 */
.nb-guest-replybar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(255, 214, 165, 0.35);
    border: 1px solid rgba(255, 178, 122, 0.6);
    border-radius: 8px;
    padding: 8px 12px;
    margin-top: 8px;
    font-size: 13px;
    color: var(--nb-ink);
}
.nb-guest-replycancel {
    border: none;
    background: none;
    cursor: pointer;
    color: var(--nb-blue-deep);
    font-size: 13px;
    font-family: var(--nb-font);
    padding: 0;
}
.nb-guest-replycancel:hover {
    text-decoration: underline;
}

.nb-guest-empty {
    text-align: center;
    color: var(--nb-ink-light);
    padding: 30px 0;
    font-size: 15px;
}

.nb-guestbook-form {
    border-top: 1px dashed rgba(74, 163, 201, 0.4);
    padding-top: 16px;
}
.nb-guest-fields {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 12px;
}
.nb-guest-fields input {
    flex: 1;
    min-width: 150px;
    padding: 10px 14px;
    border: 1px solid #cfe6f0;
    border-radius: 8px;
    font-size: 14px;
    font-family: var(--nb-font);
    background: #fff;
    outline: none;
    transition: border-color 0.2s;
}
.nb-guest-fields input:focus {
    border-color: var(--nb-blue-deep);
}
.nb-guestbook-form textarea {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid #cfe6f0;
    border-radius: 8px;
    font-size: 15px;
    font-family: var(--nb-font);
    resize: vertical;
    outline: none;
    background: #fff;
    transition: border-color 0.2s;
}
.nb-guestbook-form textarea:focus {
    border-color: var(--nb-blue-deep);
}
.nb-guest-actions {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 12px;
}
.nb-guest-msg {
    font-size: 13px;
    color: var(--nb-blue-deep);
}
.nb-guest-msg.error { color: #e06060; }
.nb-btn-submit {
    background: linear-gradient(135deg, var(--nb-blue), var(--nb-blue-deep));
}

/* =========================================================
   底部
   ========================================================= */
.nb-footer {
    margin-top: auto;
    padding-top: 30px;
    font-size: 13px;
    color: var(--nb-ink-light);
    text-align: center;
    z-index: 1;
}
.nb-footer a { color: var(--nb-blue-deep); }
.nb-footer p { margin: 4px 0; }
.nb-footer .nb-footer-icp,
.nb-footer .nb-footer-gongan {
    font-size: 12px;
}
.nb-footer .nb-footer-custom {
    font-size: 12px;
    color: var(--nb-ink-light);
    line-height: 1.6;
}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width: 720px) {
    .nb-cover-book { height: min(560px, 100%); }
    /* 留言板宽度与上方书本一致（书本手机端为 100% 且上限 470px） */
    .nb-guestbook {
        width: 100%;
        max-width: 470px;
        padding: 18px 16px;
    }

    /* 手机端：书本改为固定高度单栏，一屏一页，上下翻页（不滚动，超出一屏自动分页） */
    .nb-book {
        flex-direction: column;
        height: calc(100vh - 200px);
        width: 100%;
        max-width: 470px;
        overflow: hidden;
        background: var(--nb-paper);
        border-radius: 12px;
        box-shadow: 0 20px 45px rgba(74, 163, 201, 0.28);
    }
    .nb-book::before { display: none; }
    .nb-spine { display: none; }
    .nb-flip { display: none !important; }

    /* 手机端翻页淡入过渡 */
    .nb-book.nb-fade { animation: nbFadeIn 0.35s ease; }

    .nb-page {
        width: 100%;
        height: auto;
        overflow: hidden;
        display: flex;
    }
    .nb-page-left,
    .nb-page-right {
        border-radius: 0;
        box-shadow: none;
    }
    .nb-page-inner {
        position: relative;
        inset: auto;
        overflow: hidden;
        padding: 14px 16px;
        flex: 1 1 auto;
        min-height: 0;
    }

    /* 第1屏附件区（顶部，占约 42%，铺满） */
    .nb-page-left {
        height: 42%;
        flex: 0 0 auto;
        min-height: 0;
        border-bottom: 1px dashed rgba(74, 163, 201, 0.35);
    }
    .nb-left-inner {
        justify-content: center;
        gap: 8px;
        overflow: hidden;
    }
    /* 单图：图片铺满附件区（cover 可裁剪），点击可看大图 */
    .nb-left-inner .nb-img-single {
        width: 100%;
        height: 100%;
        object-fit: cover;
        border-radius: 6px;
        box-shadow: 0 6px 16px rgba(0,0,0,0.15);
        cursor: zoom-in;
    }
    /* 多图网格：网格铺满附件区，每张图 cover 铺满格子，点击可看大图 */
    .nb-left-inner .nb-img-grid {
        width: 100%;
        height: 100%;
        min-height: 0;
        align-content: stretch;
    }
    .nb-left-inner .nb-img-item {
        width: 100%;
        height: 100%;
        min-height: 0;
        object-fit: cover;
        cursor: zoom-in;
    }
    /* 视频铺满附件区 */
    .nb-left-inner .nb-media-video {
        height: 100%;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }
    .nb-left-inner .nb-media-video video {
        width: 100%;
        height: 100%;
        max-height: 100%;
        object-fit: contain;
    }
    .nb-left-inner .nb-media-audio {
        width: 100%;
    }

    /* 文字区（底部，占剩余高度） */
    .nb-page-right {
        flex: 1 1 auto;
        min-height: 0;
    }
    .nb-right-inner {
        padding-top: 12px;
    }
    .nb-post-title { font-size: 20px; }
    .nb-post-date { margin-bottom: 10px; padding-bottom: 8px; }
    .nb-post-content { font-size: 15px; line-height: 1.85; overflow: hidden; }
    .nb-page-num { margin-top: 4px; padding-top: 6px; }

    /* 控制栏与进度条 */
    .nb-controls { margin-top: 18px; gap: 10px; }
    .nb-btn { padding: 9px 16px; font-size: 14px; }
    .nb-pageinfo { min-width: 90px; font-size: 14px; padding: 6px 12px; }
    .nb-pagejump { width: 56px; padding: 6px 8px; font-size: 13px; }
}

/* =========================================================
   图片大图查看（lightbox）
   ========================================================= */
.nb-lightbox {
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0, 0, 0, 0.88);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    cursor: zoom-out;
    animation: nbFadeIn 0.2s ease;
}
.nb-lightbox-img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 6px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.6);
    cursor: default;
}
.nb-lightbox-close {
    position: absolute;
    top: 16px;
    right: 20px;
    width: 40px;
    height: 40px;
    line-height: 40px;
    text-align: center;
    font-size: 24px;
    color: #fff;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 50%;
    cursor: pointer;
    user-select: none;
    transition: background 0.2s ease;
}
.nb-lightbox-close:hover {
    background: rgba(255, 255, 255, 0.3);
}