/* ============================================================
   PURECOLOR · 章节页（02 中华传统色 / 03 生日色）
   与 index 共用 style.css 的变量与报头，这里只加章节版式
   ============================================================ */

/* --- 章节标题区 --- */
.chapter-head {
    padding: 54px 0 40px;
    border-bottom: 1px solid var(--ink);
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 40px;
    align-items: end;
}

.chapter-head h1 {
    font-family: var(--serif);
    font-weight: 600;
    font-size: clamp(40px, 5.4vw, 68px);
    line-height: 1.05;
    letter-spacing: -0.02em;
    margin-bottom: 18px;
}

.chapter-head .dek {
    margin-bottom: 0;
    max-width: 34em;
}

.chapter-meta {
    display: flex;
    gap: 36px;
    padding-bottom: 6px;
}

.chapter-meta div {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.chapter-meta dt {
    font-family: var(--mono);
    font-size: 9px;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--ink-3);
}

.chapter-meta dd {
    font-family: var(--mono);
    font-size: 13px;
    color: var(--ink);
    letter-spacing: 0.04em;
}

/* --- 章节主体：左索引 + 右色谱 --- */
.chapter-body {
    display: grid;
    grid-template-columns: 176px minmax(0, 1fr);
    gap: 52px;
    align-items: start;
    padding: 34px 0 40px;
}

.chapter-main,
.chapter-index,
.nav-scroll {
    min-width: 0;
}

.chapter-index {
    position: sticky;
    top: 0;
    padding-top: 6px;
    max-height: 100vh;
    overflow-y: auto;
    scrollbar-width: thin;
}

.chapter-index .side-label {
    margin-bottom: 12px;
}

.nav-scroll {
    display: flex;
    flex-direction: column;
}

.nav-item {
    font-family: var(--sans);
    font-size: 13px;
    color: var(--ink-2);
    padding: 7px 10px 7px 12px;
    border-left: 2px solid transparent;
    border-bottom: 1px solid var(--rule);
    cursor: pointer;
    transition: color 0.15s ease, border-color 0.15s ease, background 0.15s ease;
    white-space: nowrap;
}

.nav-item:last-child {
    border-bottom: 0;
}

.nav-item:hover {
    background: var(--paper-2);
    color: var(--ink);
}

.nav-item.active {
    border-left-color: var(--accent);
    color: var(--ink);
    background: var(--paper-2);
}

/* --- 节气 / 月份标题 --- */
.traditional-colors-list,
.birthday-colors-list {
    counter-reset: section;
}

.season-title,
.month-title {
    counter-increment: section;
    display: flex;
    align-items: baseline;
    gap: 14px;
    font-family: var(--serif);
    font-size: clamp(22px, 2.4vw, 28px);
    font-weight: 600;
    letter-spacing: 0.04em;
    color: var(--ink);
    padding-bottom: 10px;
    border-bottom: 1px solid var(--ink);
    margin: 0 0 24px;
    scroll-margin-top: 24px;
}

.season-title::before,
.month-title::before {
    content: counter(section, decimal-leading-zero);
    font-family: var(--mono);
    font-size: 10.5px;
    font-weight: 400;
    letter-spacing: 0.12em;
    color: var(--accent);
}

/* --- 色谱网格 --- */
.season-colors,
.birthday-colors-grid {
    counter-reset: swatch;
    display: grid;
    /* 一行最多 6 个、最少 3 个 */
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 30px 18px;
    margin-bottom: 66px;
}

@media (max-width: 1300px) {

    .season-colors,
    .birthday-colors-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

@media (max-width: 860px) {

    .season-colors,
    .birthday-colors-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

/* 色票：方块 + 细线说明 */
.color-card,
.bday-color-card {
    counter-increment: swatch;
    display: grid;
    grid-template-rows: auto 1fr;
    gap: 10px;
    align-content: start;
}

.color-preview,
.bday-color-preview {
    aspect-ratio: 1 / 1;
    cursor: pointer;
    border: 1px solid rgba(128, 128, 128, 0.28);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    position: relative;
}

.color-preview:hover,
.bday-color-preview:hover {
    transform: translateY(-3px);
    box-shadow: 4px 4px 0 var(--rule);
}

.color-info {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 2px 10px;
    align-items: baseline;
    border-top: 1px solid var(--rule);
    padding-top: 9px;
}

.color-info::before {
    content: counter(swatch, decimal-leading-zero);
    font-family: var(--mono);
    font-size: 9px;
    letter-spacing: 0.1em;
    color: var(--ink-3);
}

.color-name {
    font-family: var(--serif);
    font-size: 16.5px;
    letter-spacing: 0.05em;
    color: var(--ink);
    line-height: 1.3;
}

.color-pinyin {
    /* 数据里 457 色只有 73 条带拼音，缺的会留空行、把色值推下去。
       统一不显示，保证每行色值对齐。 */
    display: none;
}

.color-actions,
.bday-color-card .color-actions {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    margin-top: 7px;
}

.color-hex,
.bday-color-hex {
    font-family: var(--mono);
    font-size: 11px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--ink-2);
}

/* 下载按钮 */
.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 4px 7px;
    border: 1px solid var(--rule);
    border-radius: 0;
    background: transparent;
    color: var(--ink-3);
    font-family: var(--mono);
    font-size: 9px;
    letter-spacing: 0.1em;
    opacity: 0;
    transition: opacity 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.download-btn svg {
    width: 13px;
    height: 13px;
    display: block;
}

.color-card:hover .download-btn,
.bday-color-card:hover .download-btn,
.color-card:focus-within .download-btn,
.bday-color-card:focus-within .download-btn {
    opacity: 1;
}

.download-btn:hover {
    border-color: var(--ink);
    color: var(--ink);
}

@media (hover: none) {

    .download-btn {
        opacity: 1;
    }
}

/* --- 生日色：日期 / 名字 / 描述 --- */
.bday-color-info {
    display: grid;
    gap: 5px;
    border-top: 1px solid var(--rule);
    padding-top: 9px;
}

.bday-color-header {
    display: flex;
    flex-direction: column-reverse;
    align-items: flex-start;
    gap: 2px;
}

.bday-color-date {
    font-family: var(--mono);
    font-size: 9px;
    letter-spacing: 0.12em;
    color: var(--accent);
    white-space: nowrap;
}

.bday-color-name {
    font-family: var(--serif);
    font-size: 17px;
    letter-spacing: 0.05em;
}

.bday-color-desc {
    font-size: 12px;
    line-height: 1.75;
    min-height: 3.5em;
    color: var(--ink-2);
    letter-spacing: 0.01em;
}

.bday-color-card .color-actions {
    margin-top: 2px;
}

/* --- 响应式 --- */
@media (max-width: 1000px) {
    .chapter-body {
        grid-template-columns: minmax(0, 1fr);
        gap: 26px;
        padding-top: 22px;
    }

    .chapter-index {
        position: sticky;
        top: 0;
        z-index: 30;
        max-height: none;
        overflow: visible;
        padding: 10px 0;
        background: var(--paper);
        border-bottom: 1px solid var(--rule);
    }

    .chapter-index .side-label {
        display: none;
    }

    .nav-scroll {
        flex-direction: row;
        overflow-x: auto;
        gap: 4px;
        scrollbar-width: none;
    }

    .nav-scroll::-webkit-scrollbar {
        display: none;
    }

    .nav-item {
        border-bottom: 0;
        border-left: 0;
        border-bottom: 2px solid transparent;
        padding: 6px 10px;
    }

    .nav-item.active {
        border-left-color: transparent;
        border-bottom-color: var(--accent);
        background: transparent;
    }

    .chapter-head {
        grid-template-columns: 1fr;
        gap: 22px;
        padding: 38px 0 26px;
    }

    .chapter-meta {
        gap: 26px;
    }

    .season-colors,
    .birthday-colors-grid {
        gap: 24px 14px;
        margin-bottom: 46px;
    }
}

@media (max-width: 680px) {
    .birthday-colors-grid {
        gap: 22px 12px;
    }

    .bday-color-name {
        font-size: 15px;
    }

    .bday-color-desc {
        font-size: 11px;
        line-height: 1.6;
    }

    .bday-color-hex {
        font-size: 10px;
    }

    /* 三列时按钮只留图标，省出宽度给色值 */
    .download-btn {
        font-size: 0;
        padding: 4px 5px;
    }
}

@media (max-width: 560px) {

    .color-name {
        font-size: 15px;
    }
}

/* 主题图标：浅色显示月亮，深色显示太阳 */
.theme-tgl .sun-ic {
    display: none;
}

[data-theme="dark"] .theme-tgl .sun-ic {
    display: block;
}

[data-theme="dark"] .theme-tgl .moon-ic {
    display: none;
}