/* ============================================================
   变量 / 基础
   ============================================================ */
:root {
    --reading-size: 1.125rem;

    --paper: #f4f3ef;
    --ink: #1a1a1a;
    --slate: #5c5d5e;
    --crimson: #8b2626;

    --w-wide: 64rem;
    --w-narrow: 48rem;

    color-scheme: light;
}

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

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--paper);
    color: var(--ink);
    font-family: 'Noto Serif SC', serif;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1,
h2,
h3,
p {
    margin: 0;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font: inherit;
    color: inherit;
    background: none;
    border: none;
    padding: 0;
    cursor: pointer;
}

.container {
    max-width: var(--w-wide);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ============================================================
   导航栏
   ============================================================ */
.site-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 40;

    background: rgba(244, 243, 239, 0.85);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);

    border-bottom: 1px solid rgba(26, 26, 26, 0.06);

    transition: padding-right 0.2s ease;
}

.nav-inner {
    position: relative;

    display: flex;
    justify-content: space-between;
    align-items: center;

    gap: 1rem;

    padding-top: 1rem;
    padding-bottom: 1rem;
}

/* ============================================================
   返回
   ============================================================ */
.nav-back {
    display: flex;
    align-items: center;
    gap: 0.5rem;

    flex-shrink: 0;

    font-size: 0.875rem;
    line-height: 1.25rem;
    letter-spacing: 0.1em;

    color: var(--slate);

    transition:
            color 0.3s ease,
            opacity 0.3s ease;
}

.nav-back:hover {
    color: var(--ink);
}

.nav-back-arrow {
    font-size: 1rem;
    line-height: 1;
}

.nav-back-label {
    display: none;
}

/* ============================================================
   Picker
   ============================================================ */
.picker {
    position: relative;
}

.picker-trigger {
    position: relative;

    display: inline-flex;
    align-items: center;

    gap: 0.5rem;

    padding: 0.15rem 0.05rem 0.35rem;

    font-size: 0.75rem;
    line-height: 1.2;
    letter-spacing: 0.25em;

    color: var(--slate);
    white-space: nowrap;

    transition: color 0.3s ease;
}

.picker-trigger::after {
    content: "";

    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;

    height: 1px;

    background: rgba(26, 26, 26, 0.15);
}

.picker-trigger::before {
    content: "";

    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;

    height: 1px;

    background: var(--crimson);

    transform: scaleX(0);
    transform-origin: left center;

    transition:
            transform 0.45s cubic-bezier(.25, .46, .45, .94);

    z-index: 1;
}

.picker:hover .picker-trigger::before,
.picker.is-open .picker-trigger::before {
    transform: scaleX(1);
}

.picker:hover .picker-trigger,
.picker.is-open .picker-trigger {
    color: var(--ink);
}

/* ============================================================
   箭头
   ============================================================ */
.picker-caret {
    width: 5px;
    height: 5px;

    margin-top: -2px;

    border-right: 1.2px solid currentColor;
    border-bottom: 1.2px solid currentColor;

    transform: rotate(45deg);

    transition:
            transform 0.3s ease,
            border-color 0.3s ease;
}

.picker.is-open .picker-caret {
    transform: rotate(-135deg);
    margin-top: 2px;

    border-color: var(--crimson);
}

/* ============================================================
   Picker 面板
   ============================================================ */
.picker-panel {
    --tx: 0;

    position: absolute;

    top: calc(100% + 0.75rem);

    min-width: 9.5rem;

    padding: 0.35rem;

    background: #fbfaf7;

    border: 1px solid rgba(26, 26, 26, 0.08);

    box-shadow:
            0 18px 40px -14px rgba(26, 26, 26, 0.22),
            0 4px 12px -4px rgba(26, 26, 26, 0.08),
            0 0 0 1px rgba(244, 243, 239, 0.6);

    opacity: 0;
    visibility: hidden;

    transform: translate(var(--tx), -8px) scale(0.98);

    transform-origin: top right;

    transition:
            opacity 0.22s ease,
            transform 0.22s cubic-bezier(.25, .46, .45, .94),
            visibility 0s linear 0.22s;

    z-index: 50;
}

.picker.is-open .picker-panel {
    opacity: 1;
    visibility: visible;

    transform: translate(var(--tx), 0) scale(1);

    transition:
            opacity 0.25s ease,
            transform 0.25s cubic-bezier(.25, .46, .45, .94),
            visibility 0s;
}

.picker-panel::before {
    content: "";

    position: absolute;
    top: -5px;

    width: 8px;
    height: 8px;

    background: #fbfaf7;

    border-top: 1px solid rgba(26, 26, 26, 0.08);
    border-left: 1px solid rgba(26, 26, 26, 0.08);

    transform: rotate(45deg);
}

/* ============================================================
   Picker option
   ============================================================ */
.picker-option {
    position: relative;

    display: flex;
    align-items: center;

    width: 100%;

    padding: 0.5rem 0.8rem 0.5rem 0.9rem;

    font-size: 0.75rem;
    line-height: 1.2;
    letter-spacing: 0.12em;

    color: var(--slate);
    text-align: left;
    white-space: nowrap;

    transition:
            background-color 0.2s ease,
            color 0.2s ease;
}

.picker-option::before {
    content: "";

    position: absolute;

    left: 0;
    top: 7px;
    bottom: 7px;

    width: 2px;

    background: var(--crimson);

    transform: scaleY(0);
    transform-origin: center;

    transition:
            transform 0.28s cubic-bezier(.25, .46, .45, .94);
}

.picker-option:hover {
    background: rgba(139, 38, 38, 0.045);
    color: var(--ink);
}

.picker-option.is-selected {
    color: var(--crimson);
}

.picker-option.is-selected::before {
    transform: scaleY(1);
}

.picker-option + .picker-option {
    border-top: 1px dashed rgba(26, 26, 26, 0.06);
}

/* ============================================================
   隐藏原生 select
   ============================================================ */
.picker-native {
    position: absolute;

    width: 1px;
    height: 1px;

    padding: 0;
    margin: -1px;

    overflow: hidden;

    clip: rect(0, 0, 0, 0);

    white-space: nowrap;

    border: 0;

    pointer-events: none;
}

/* ============================================================
   章节 Picker
   ============================================================ */
.chapter-picker {
    position: absolute;

    left: 50%;
    top: 50%;

    transform: translate(-50%, -50%);

    z-index: 45;
}

.chapter-picker .picker-panel {
    --tx: -50%;

    left: 50%;

    transform-origin: top center;
}

.chapter-picker .picker-panel::before {
    left: 50%;
    margin-left: -4px;
}

/* ============================================================
   译者 Picker
   ============================================================ */
.translator-picker .picker-panel {
    right: 0;
}

.translator-picker .picker-panel::before {
    right: 1.5rem;
}

.translator-picker .picker-trigger {
    gap: 0.55rem;

    font-size: 0.8125rem;
    letter-spacing: 0.12em;
}

/* ============================================================
   右侧工具
   ============================================================ */
.nav-tools {
    display: flex;
    align-items: center;

    gap: 0.75rem;

    flex-shrink: 0;

    font-size: 0.75rem;
    letter-spacing: 0.1em;

    color: var(--slate);
}

.nav-tools .divider {
    width: 1px;
    height: 0.75rem;

    background: rgba(26, 26, 26, 0.15);
}

.size-btn {
    opacity: 0.6;

    transition:
            color 0.3s ease,
            opacity 0.3s ease;
}

.size-btn:hover {
    opacity: 1;
    color: var(--ink);
}

/* ============================================================
   阅读进度条
   ============================================================ */
.progress-bar {
    position: absolute;

    left: 0;
    bottom: 0;

    height: 2px;
    width: 0;

    background: var(--crimson);

    transition: width 0.08s linear;
}

/* ============================================================
   文章
   ============================================================ */
.article {
    padding: 9rem 1.5rem 6rem;
}

.article-inner {
    max-width: var(--w-narrow);

    margin: 0 auto;
}

/* ============================================================
   正文
   ============================================================ */
.reading-body {
    opacity: 1;
    transform: none;
}

.reading-body p {
    font-size: var(--reading-size);
    line-height: 2;

    letter-spacing: 0.04em;

    text-indent: 2em;

    margin-bottom: 2rem;

    color: #262626;

    font-weight: 300;

    text-align: justify;

    word-break: break-word;
}

/* ============================================================
   首字下沉
   ============================================================ */
.drop-cap::first-letter {
    float: left;

    font-size: 3.6em;
    line-height: 0.9;

    padding-right: 0.12em;
    padding-top: 0.05em;

    color: var(--crimson);

    font-weight: 400;
}

/* ============================================================
   章节上下页
   ============================================================ */
.chapter-nav {
    margin-top: 7rem;

    padding-top: 3rem;

    border-top: 1px solid rgba(26, 26, 26, 0.1);
}

.chapter-nav-inner {
    display: flex;

    flex-direction: column;

    justify-content: space-between;

    align-items: center;

    gap: 1.5rem;

    font-size: 0.875rem;

    letter-spacing: 0.1em;

    color: var(--slate);
}

.chapter-link {
    position: relative;

    color: var(--slate);

    transition:
            color 0.3s ease,
            opacity 0.3s ease;
}

.chapter-link:hover {
    color: var(--ink);
}

.chapter-link::after {
    content: "";

    position: absolute;

    left: 0;
    bottom: -4px;

    width: 0;
    height: 1px;

    background: var(--crimson);

    transition:
            width 0.4s ease;
}

.chapter-link:hover::after {
    width: 100%;
}

/* Java 隐藏上下章时 */
.chapter-link[hidden] {
    display: none !important;
}

/* 第一章：只有下一章，放左边 */
.chapter-nav-inner.only-next {
    justify-content: flex-start;
}

/* 最后一章：只有上一章，放右边 */
.chapter-nav-inner.only-previous {
    justify-content: flex-end;
}

/* 没有对应章节的占位链接 */
.chapter-link-placeholder {
    visibility: hidden;
    pointer-events: none;
    user-select: none;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
    border-top: 1px solid rgba(26, 26, 26, 0.1);

    background: rgba(236, 235, 230, 0.5);

    padding: 3rem 1.5rem;
}

.footer-inner {
    max-width: var(--w-wide);

    margin: 0 auto;

    display: flex;

    flex-direction: column;

    justify-content: space-between;

    align-items: center;

    gap: 1.5rem;
}

.footer-brand {
    display: flex;
    align-items: center;

    gap: 1rem;
}

.footer-brand-text {
    font-size: 0.875rem;
    letter-spacing: 0.1em;

    color: var(--slate);
}

.footer-copy {
    font-size: 0.75rem;

    letter-spacing: 0.1em;

    color: var(--slate);

    opacity: 0.6;
}

/* ============================================================
   印章
   ============================================================ */
.hanko {
    display: inline-block;

    padding: 4px 8px;

    border: 2px solid var(--crimson);

    border-radius: 2px;

    color: var(--crimson);

    font-size: 0.9rem;

    font-weight: 700;

    letter-spacing: 2px;

    writing-mode: vertical-rl;

    text-orientation: upright;
}

/* ============================================================
   注释
   ============================================================ */
.note {
    position: relative;

    border-bottom: 1px dashed var(--crimson);

    cursor: pointer;

    transition:
            border-color 0.2s ease,
            color 0.2s ease;
}

.note:hover {
    border-bottom-color: var(--ink);

    color: var(--crimson);
}

.note:focus-visible {
    outline: 2px solid var(--crimson);
    outline-offset: 3px;
}

.note.is-empty {
    border-bottom: 0;

    cursor: inherit;
}

.note.is-empty:hover {
    color: inherit;
}

.note.is-open::after,
.note.is-open::before {
    opacity: 0 !important;
    visibility: hidden !important;
}

/* ============================================================
   注释悬浮提示
   ============================================================ */
.note::after {
    content: attr(data-note);

    position: absolute;

    left: 50%;
    bottom: calc(100% + 10px);

    transform:
            translateX(-50%)
            translateY(4px);

    /*
     * 不再固定 3 行。
     * 给提示框一个比较舒服的最大宽度，让中文自然换行。
     */
    width: max-content;
    max-width: 36rem;

    /*
     * 防止长注释被裁掉。
     */
    box-sizing: border-box;

    padding: 0.7rem 1rem;

    background: #fbfaf7;

    border: 1px solid rgba(26, 26, 26, 0.08);
    border-left: 2px solid var(--crimson);

    box-shadow:
            0 12px 28px -10px rgba(26, 26, 26, 0.22),
            0 2px 8px -4px rgba(26, 26, 26, 0.08);

    font-size: 0.9rem;

    /*
     * 比之前稍微紧一点。
     */
    line-height: 1.55;

    letter-spacing: 0.03em;

    color: var(--ink);

    text-align: left;
    text-indent: 0;

    white-space: normal;
    overflow-wrap: break-word;
    word-break: break-word;

    opacity: 0;
    visibility: hidden;
    pointer-events: none;

    transition:
            opacity 0.2s ease,
            transform 0.2s ease,
            visibility 0s linear 0.2s;

    z-index: 100;
}

.note::before {
    content: "";

    position: absolute;

    left: 50%;
    bottom: calc(100% + 4px);

    margin-left: -5px;

    width: 10px;
    height: 10px;

    background: #fbfaf7;

    border-top: 1px solid rgba(26, 26, 26, 0.08);
    border-left: 1px solid rgba(26, 26, 26, 0.08);

    transform:
            rotate(45deg)
            translateY(4px);

    opacity: 0;

    visibility: hidden;

    pointer-events: none;

    transition:
            opacity 0.2s ease,
            transform 0.2s ease,
            visibility 0s linear 0.2s;

    z-index: 99;
}

.note:hover::after,
.note:focus-visible::after {
    opacity: 1;

    visibility: visible;

    transform:
            translateX(-50%)
            translateY(0);

    transition:
            opacity 0.2s ease,
            transform 0.2s ease,
            visibility 0s;
}

.note:hover::before,
.note:focus-visible::before {
    opacity: 1;

    visibility: visible;

    transform:
            rotate(45deg)
            translateY(0);

    transition:
            opacity 0.2s ease,
            transform 0.2s ease,
            visibility 0s;
}

/* ============================================================
   滚动锁定
   ============================================================ */
html.is-scroll-locked {
    overflow: hidden;
}

html.is-scroll-locked body {
    padding-right: var(--scrollbar-w, 0);
}

html.is-scroll-locked .site-nav {
    padding-right: var(--scrollbar-w, 0);
}

/* ============================================================
   注释弹窗
   JS 动态创建
   ============================================================ */
.note-modal {
    position: fixed;

    inset: 0;

    z-index: 200;

    display: flex;

    align-items: center;
    justify-content: center;

    padding: 1.5rem;

    /*
     * 关键改动：
     * 父级只负责显隐，不做 opacity 过渡。
     * 淡入淡出完全交给 backdrop 和 card 各自处理，
     * 避免双层 opacity 叠加导致背景模糊滞后。
     */
    visibility: hidden;

    pointer-events: none;

    /* 关闭时，等子元素淡出完再隐藏 */
    transition: visibility 0s linear 0.38s;
}

.note-modal.is-open {
    visibility: visible;

    pointer-events: auto;

    transition: visibility 0s;
}

.note-modal-backdrop {
    position: absolute;

    inset: 0;

    background: rgba(26, 26, 26, 0.38);

    /*
     * 让模糊从 0 开始过渡，
     * 避免 Chrome 在 backdrop-filter 淡入时慢半拍。
     */
    -webkit-backdrop-filter: blur(0px);
    backdrop-filter: blur(0px);

    opacity: 0;

    will-change: opacity, backdrop-filter;

    transition:
            opacity 0.28s ease,
            -webkit-backdrop-filter 0.28s ease,
            backdrop-filter 0.28s ease;
}

.note-modal.is-open .note-modal-backdrop {
    opacity: 1;

    -webkit-backdrop-filter: blur(6px);
    backdrop-filter: blur(6px);
}

.note-modal-card {
    position: relative;

    width: min(30rem, 100%);

    max-height: min(72vh, 34rem);

    overflow-y: auto;

    padding: 2rem 2rem 1.9rem;

    background: #fbfaf7;

    border: 1px solid rgba(26, 26, 26, 0.08);

    border-top: 2px solid var(--crimson);

    box-shadow:
            0 30px 70px -20px rgba(26, 26, 26, 0.38),
            0 4px 14px -6px rgba(26, 26, 26, 0.12);

    opacity: 0;

    transform:
            translateY(16px)
            scale(0.97);

    transition:
            opacity 0.28s ease,
            transform 0.38s cubic-bezier(.25, .46, .45, .94);
}

.note-modal.is-open .note-modal-card {
    opacity: 1;

    transform:
            translateY(0)
            scale(1);
}

.note-modal-term {
    margin-bottom: 0.9rem;

    font-size: 1.4rem;

    line-height: 1.4;

    letter-spacing: 0.3em;

    color: var(--crimson);
}

.note-modal-text {
    font-size: 1rem;

    line-height: 2;

    letter-spacing: 0.04em;

    color: #262626;

    font-weight: 300;

    text-align: justify;

    word-break: break-word;
}

.note-modal-close {
    position: absolute;

    top: 0.75rem;
    right: 0.75rem;

    display: flex;

    align-items: center;
    justify-content: center;

    width: 2rem;
    height: 2rem;

    color: var(--slate);

    opacity: 0.5;

    transition:
            opacity 0.25s ease,
            color 0.25s ease,
            transform 0.3s ease;
}

.note-modal-close:hover {
    opacity: 1;

    color: var(--crimson);

    transform: rotate(90deg);
}

.note-modal-close span {
    position: relative;

    width: 14px;
    height: 14px;
}

.note-modal-close span::before,
.note-modal-close span::after {
    content: "";

    position: absolute;

    left: 50%;
    top: 50%;

    width: 14px;
    height: 1px;

    background: currentColor;
}

.note-modal-close span::before {
    transform:
            translate(-50%, -50%)
            rotate(45deg);
}

.note-modal-close span::after {
    transform:
            translate(-50%, -50%)
            rotate(-45deg);
}

.note-modal-card::-webkit-scrollbar {
    width: 6px;
}

.note-modal-card::-webkit-scrollbar-track {
    background: transparent;
}

.note-modal-card::-webkit-scrollbar-thumb {
    background: rgba(26, 26, 26, 0.18);

    border-radius: 3px;
}

/* ============================================================
   兼容模板中原本存在的 reveal class
   不再隐藏任何内容
   ============================================================ */
@keyframes reveal-up {
    from {
        opacity: 0;
        transform: translateY(24px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 正文进入 */
.reading-body.reveal {
    animation:
            reveal-up 1s cubic-bezier(.25, .46, .45, .94)
            both;
}

/* 正文稍微延迟一点 */
.reading-body.reveal-delay-1 {
    animation-delay: 0.15s;
}

/* 上下章导航比正文晚一点出现 */
.chapter-nav.reveal {
    animation:
            reveal-up 0.9s cubic-bezier(.25, .46, .45, .94)
            0.35s both;
}

/* 减少动态效果的系统设置 */
@media (prefers-reduced-motion: reduce) {
    .reading-body.reveal,
    .chapter-nav.reveal {
        animation: none;
        opacity: 1;
        transform: none;
    }
}

/* ============================================================
   滚动条
   ============================================================ */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--paper);
}

::-webkit-scrollbar-thumb {
    background: var(--slate);

    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--ink);
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 480px) {
    .chapter-picker .picker-trigger {
        gap: 0.35rem;

        font-size: 0.6875rem;

        letter-spacing: 0.15em;
    }

    .chapter-picker .picker-panel {
        min-width: 9rem;
    }

    .note::after {
        max-width: min(20rem, calc(100vw - 2rem));
    }

    .note-modal {
        padding: 1rem;
    }

    .note-modal-card {
        padding: 1.6rem 1.25rem 1.5rem;

        max-height: 76vh;
    }

    .note-modal-text {
        font-size: 0.9375rem;

        line-height: 1.95;
    }
}

@media (min-width: 640px) {
    .nav-back-label {
        display: inline;
    }

    .chapter-picker .picker-trigger {
        font-size: 0.875rem;
    }

    .chapter-nav-inner {
        flex-direction: row;
    }
}

@media (min-width: 768px) {
    .article {
        padding-top: 11rem;
    }

    .footer-inner {
        flex-direction: row;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    .picker-panel,
    .picker-trigger::before,
    .picker-caret,
    .note::after,
    .note::before,
    .note-modal,
    .note-modal-backdrop,
    .note-modal-card,
    .chapter-link::after {
        transition: none !important;
    }
}