/* =========================================================================
   百香集 · 香源考（index）
   页面级排版：香源总论 / 香源产地 / 香路纪年
   ========================================================================= */

/* ---------- 香源总论 ---------- */
.section-intro { overflow: hidden; }

.intro-layout {
    display: grid;
    grid-template-columns: minmax(0, 748px) 232px;
    gap: 60px;
    align-items: start;
    max-width: 1040px;
    margin: 0 auto;
}

.intro-body .lead {
    padding-left: 24px;
    border-left: 2px solid var(--accent);
    font-size: 17px;
    line-height: 2;
    color: var(--ink);
    letter-spacing: .4px;
    text-align: justify;
}

.intro-columns {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 38px;
}

.intro-columns p {
    font-size: 14px;
    line-height: 2.15;
    color: var(--ink-2);
    text-align: justify;
}

.intro-aside {
    position: sticky;
    top: calc(var(--nav-h-sm) + 48px);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding-top: 4px;
}

.intro-mark {
    font-family: var(--font-title);
    font-size: clamp(120px, 12vw, 176px);
    line-height: .9;
    color: rgba(140, 90, 58, .10);
    user-select: none;
}

.intro-vertical {
    writing-mode: vertical-rl;
    font-family: var(--font-deco);
    font-size: 14px;
    line-height: 2.2;
    letter-spacing: 8px;
    color: var(--ink-3);
    text-align: center;
}

.intro-aside::before {
    content: "";
    width: 1px;
    height: 64px;
    background: linear-gradient(180deg, rgba(140, 90, 58, 0), rgba(140, 90, 58, .45), rgba(140, 90, 58, 0));
}

/* ---------- 香源产地 ---------- */
.origin-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 38px 36px;
}

.origin-card {
    position: relative;
    display: flex;
    flex-direction: column;
    background: var(--card);
    border: 1px solid var(--line);
    overflow: hidden;
    transition: transform .45s var(--ease), box-shadow .45s var(--ease),
                border-color .45s var(--ease);
}

.origin-card::after {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    transform: scaleX(0);
    transform-origin: left center;
    transition: transform .5s var(--ease);
    z-index: 3;
}

.origin-card:hover {
    transform: translateY(-6px);
    border-color: rgba(140, 90, 58, .5);
    box-shadow: var(--shadow-hover);
}

.origin-card:hover::after { transform: scaleX(1); }

.origin-media {
    position: relative;
    aspect-ratio: 16 / 10;
    overflow: hidden;
    background: var(--paper-alt);
    border-bottom: 1px solid var(--line);
    cursor: zoom-in;
}

.origin-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform .8s var(--ease-out);
}

.origin-card:hover .origin-media img { transform: scale(1.05); }

.origin-media::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(0deg, rgba(61, 50, 38, .16), rgba(61, 50, 38, 0) 42%);
    opacity: 0;
    transition: opacity .45s var(--ease);
}

.origin-card:hover .origin-media::after { opacity: 1; }

.origin-body {
    position: relative;
    flex: 1;
    padding: 28px 32px 32px;
}

.origin-index {
    position: absolute;
    top: 14px;
    right: 24px;
    font-family: var(--font-title);
    font-size: 40px;
    line-height: 1;
    letter-spacing: 1px;
    color: rgba(140, 90, 58, .16);
    transition: color .4s var(--ease);
    user-select: none;
}

.origin-card:hover .origin-index { color: rgba(166, 61, 47, .28); }

.origin-body h3 {
    position: relative;
    margin-bottom: 14px;
    padding-bottom: 12px;
    padding-right: 64px;
    font-family: var(--font-title);
    font-weight: 400;
    font-size: 22px;
    line-height: 1.5;
    letter-spacing: 3px;
    color: var(--ink);
}

.origin-body h3::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 46px;
    height: 1px;
    background: var(--accent);
    opacity: .6;
}

.origin-char {
    margin-bottom: 10px;
    font-size: 13.5px;
    line-height: 1.9;
    color: var(--ink-2);
}

.origin-char b {
    margin-right: 9px;
    padding-bottom: 1px;
    font-weight: 400;
    letter-spacing: 2px;
    color: var(--accent);
    border-bottom: 1px solid rgba(140, 90, 58, .38);
}

.origin-note {
    font-size: 14px;
    line-height: 2.05;
    color: var(--ink-2);
    text-align: justify;
}

/* ---------- 香路纪年 ---------- */
.timeline {
    position: relative;
    max-width: 1020px;
    margin: 0 auto;
    padding-top: 6px;
}

.timeline-rail {
    position: absolute;
    left: 151px;
    top: 10px;
    bottom: 10px;
    width: 2px;
    background: var(--line-soft);
    border-radius: 2px;
    overflow: hidden;
}

.timeline-fill {
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    height: var(--fill, 0%);
    background: linear-gradient(180deg, var(--accent), var(--accent-2));
    border-radius: 2px;
    transition: height .2s linear;
}

.route-node {
    position: relative;
    display: grid;
    grid-template-columns: 120px 1fr;
    column-gap: 62px;
    padding-bottom: 22px;
}

.route-node::before {
    content: "";
    position: absolute;
    left: 146px;
    top: 20px;
    z-index: 1;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--paper);
    border: 2px solid var(--line);
    transition: background .35s var(--ease), border-color .35s var(--ease),
                transform .35s var(--ease), box-shadow .35s var(--ease);
}

.route-node.is-active::before {
    background: var(--accent-2);
    border-color: var(--accent-2);
    transform: scale(1.12);
    box-shadow: 0 0 0 5px rgba(166, 61, 47, .12);
}

.route-era {
    justify-self: end;
    align-self: start;
    margin-top: 13px;
    padding-bottom: 3px;
    font-family: var(--font-deco);
    font-size: 15px;
    letter-spacing: 4px;
    color: var(--ink-3);
    border-bottom: 1px solid var(--line);
    transition: color .35s var(--ease), border-color .35s var(--ease);
}

.route-node.is-active .route-era {
    color: var(--accent-2);
    border-color: var(--accent-2);
}

.route-body {
    position: relative;
    padding: 22px 56px 22px 26px;
    background: var(--card);
    border: 1px solid var(--line);
    border-left: 2px solid transparent;
    cursor: pointer;
    transition: border-color .35s var(--ease), box-shadow .35s var(--ease),
                transform .35s var(--ease), background .35s var(--ease);
}

.route-body:hover {
    border-color: rgba(140, 90, 58, .45);
    box-shadow: var(--shadow-2);
}

.route-node.is-active .route-body {
    border-left-color: var(--accent-2);
    background: #FCF8F0;
}

.route-body:focus-visible { outline-offset: 2px; }

.route-body h3 {
    margin-bottom: 7px;
    font-family: var(--font-title);
    font-weight: 400;
    font-size: 20px;
    line-height: 1.6;
    letter-spacing: 3px;
    color: var(--ink);
}

.route-desc {
    font-size: 14px;
    line-height: 1.95;
    color: var(--ink-2);
}

.route-detail {
    max-height: 0;
    margin-top: 0;
    padding-top: 0;
    overflow: hidden;
    font-size: 13px;
    line-height: 1.95;
    color: var(--accent);
    border-top: 1px dashed transparent;
    opacity: 0;
    transition: max-height .5s var(--ease), opacity .4s var(--ease),
                margin-top .5s var(--ease), padding-top .5s var(--ease);
}

.route-node.is-open .route-detail {
    max-height: 260px;
    margin-top: 12px;
    padding-top: 12px;
    border-top-color: var(--line);
    opacity: 1;
}

.route-caret {
    position: absolute;
    right: 24px;
    top: 30px;
    width: 7px;
    height: 7px;
    border-right: 1.4px solid var(--ink-3);
    border-bottom: 1.4px solid var(--ink-3);
    transform: rotate(45deg);
    transition: transform .35s var(--ease), border-color .35s var(--ease);
}

.route-node.is-open .route-caret {
    transform: rotate(225deg);
    border-color: var(--accent-2);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1180px) {
    .intro-layout { grid-template-columns: minmax(0, 1fr) 180px; gap: 44px; }
    .origin-grid { gap: 28px; }
    .origin-body { padding: 24px 26px 28px; }
    .origin-index { font-size: 34px; right: 20px; }
    .timeline-rail { left: 121px; }
    .route-node { grid-template-columns: 96px 1fr; column-gap: 46px; }
    .route-node::before { left: 115px; }
}

@media (max-width: 900px) {
    .intro-layout { grid-template-columns: 1fr; gap: 34px; }
    .intro-aside {
        position: static;
        flex-direction: row;
        justify-content: flex-start;
        gap: 18px;
        padding: 0;
    }
    .intro-aside::before { width: 42px; height: 1px; background: var(--line); }
    .intro-mark { font-size: 88px; }
    .intro-vertical { writing-mode: horizontal-tb; letter-spacing: 4px; line-height: 1.9; }

    .intro-columns { grid-template-columns: 1fr; gap: 20px; margin-top: 28px; }
    .intro-body .lead { font-size: 16px; }

    .origin-grid { grid-template-columns: 1fr; gap: 24px; }

    /* 时间轴改为左侧细轴 */
    .timeline { padding-left: 0; }
    .timeline-rail { left: 7px; top: 6px; bottom: 6px; }
    .route-node {
        grid-template-columns: 1fr;
        padding: 0 0 18px 34px;
    }
    .route-node::before { left: 2px; top: 8px; width: 10px; height: 10px; }
    .route-era {
        justify-self: start;
        margin: 0 0 8px;
        font-size: 14px;
        letter-spacing: 3px;
    }
    .route-body { padding: 20px 46px 20px 20px; }
    .route-body h3 { font-size: 18px; }
    .route-caret { top: 26px; right: 18px; }
}

@media (max-width: 600px) {
    .origin-body { padding: 22px 20px 24px; }
    .origin-body h3 { font-size: 20px; padding-right: 54px; }
    .origin-note { font-size: 13.5px; }
    .intro-mark { font-size: 68px; }
    .intro-vertical { font-size: 12.5px; letter-spacing: 2px; }
}