:root {
    --paper: #f2f1e9;
    --paper-deep: #d9d8d0;
    --ink: #3d3d3b;
    --ink-soft: #77756f;
    --wood: #58463c;
    --line: rgba(61, 61, 59, 0.2);
    --white: #fff;
    --serif: "Noto Serif TC", "Source Han Serif TC", "PMingLiU", serif;
    --sans: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", sans-serif;
    --page-pad: clamp(20px, 4vw, 64px);
    --section-space: clamp(104px, 14vw, 220px);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--paper);
    font-family: var(--sans);
    font-size: 15px;
    font-weight: 300;
    line-height: 1.9;
    letter-spacing: 0.06em;
}

body,
a,
button {
    color: var(--ink);
}

a {
    text-decoration: none;
}

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

button {
    font: inherit;
}

.skip-link {
    position: fixed;
    top: 10px;
    left: 10px;
    z-index: 100;
    padding: 8px 14px;
    background: var(--paper);
    transform: translateY(-160%);
}

.skip-link:focus {
    transform: translateY(0);
}

.reference-header {
    position: fixed;
    inset: 0 0 auto;
    z-index: 20;
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    min-height: 72px;
    padding: 0 var(--page-pad);
    border-bottom: 1px solid rgba(255, 255, 255, 0.36);
    color: var(--white);
    background: linear-gradient(to bottom, rgba(23, 26, 23, 0.34), transparent);
    transition: color 0.5s ease, background-color 0.5s ease;
}

.reference-header a {
    color: inherit;
}

.reference-brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    justify-self: start;
    font-family: var(--serif);
    font-size: 17px;
    letter-spacing: 0.13em;
}

.reference-brand__mark {
    display: block;
    width: 9px;
    height: 9px;
    border: 1px solid currentColor;
    border-radius: 50%;
}

.reference-nav {
    display: flex;
    gap: clamp(18px, 3vw, 42px);
    font-size: 11px;
    letter-spacing: 0.14em;
}

.reference-nav a,
.reference-back {
    position: relative;
}

.reference-nav a::after,
.reference-back::after {
    position: absolute;
    right: 0;
    bottom: -6px;
    left: 0;
    height: 1px;
    background: currentColor;
    content: "";
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.45s ease;
}

.reference-nav a:hover::after,
.reference-nav a:focus-visible::after,
.reference-back:hover::after,
.reference-back:focus-visible::after {
    transform: scaleX(1);
    transform-origin: left;
}

.reference-back {
    justify-self: end;
    font-size: 11px;
    letter-spacing: 0.1em;
}

.hero {
    position: relative;
    display: grid;
    align-items: center;
    min-height: 100svh;
    overflow: hidden;
    color: var(--white);
}

.hero__image,
.hero__veil {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

.hero__image {
    object-fit: cover;
    object-position: 56% center;
    filter: saturate(0.62) contrast(0.9) brightness(0.82) sepia(0.08);
    animation: hero-breathe 16s ease-in-out infinite alternate;
}

.hero__veil {
    background:
        linear-gradient(90deg, rgba(25, 27, 24, 0.3), transparent 48%),
        linear-gradient(0deg, rgba(25, 27, 24, 0.44), transparent 52%);
}

.hero__eyebrow,
.hero__title-wrap,
.hero__note,
.hero__scroll {
    position: absolute;
    z-index: 2;
}

.hero__eyebrow {
    top: 104px;
    left: var(--page-pad);
    margin: 0;
    font-size: 10px;
    letter-spacing: 0.2em;
}

.hero__title-wrap {
    left: clamp(24px, 12vw, 180px);
    bottom: clamp(120px, 18vh, 200px);
}

.hero__kicker {
    margin: 0 0 22px;
    font-family: var(--serif);
    font-size: 13px;
    letter-spacing: 0.2em;
}

.hero h1 {
    margin: 0;
    font-family: var(--serif);
    font-size: clamp(42px, 6.4vw, 94px);
    font-weight: 400;
    line-height: 1.35;
    letter-spacing: 0.08em;
    text-shadow: 0 2px 22px rgba(0, 0, 0, 0.12);
}

.hero__note {
    right: var(--page-pad);
    bottom: 64px;
    width: min(390px, 42vw);
    margin: 0;
    padding-left: 20px;
    border-left: 1px solid rgba(255, 255, 255, 0.55);
    font-family: var(--serif);
    font-size: 13px;
    line-height: 2;
}

.hero__scroll {
    bottom: 52px;
    left: var(--page-pad);
    display: flex;
    align-items: center;
    gap: 14px;
    color: var(--white);
    font-size: 9px;
    letter-spacing: 0.2em;
    writing-mode: vertical-rl;
}

.hero__scroll-line {
    width: 1px;
    height: 48px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.4);
}

.hero__scroll-line::after {
    display: block;
    width: 100%;
    height: 55%;
    background: var(--white);
    content: "";
    animation: scroll-line 2.4s ease-in-out infinite;
}

.section-index {
    display: flex;
    align-items: flex-start;
    gap: 18px;
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
}

.section-index span {
    display: grid;
    place-items: center;
    width: 36px;
    height: 36px;
    border: 1px solid var(--line);
    border-radius: 50%;
    font-size: 10px;
}

.section-index p {
    margin: 5px 0 0;
}

.section-index--light span {
    border-color: rgba(255, 255, 255, 0.38);
}

.eyebrow {
    margin: 0 0 22px;
    font-size: 10px;
    letter-spacing: 0.24em;
}

.principles {
    display: grid;
    grid-template-columns: minmax(160px, 0.75fr) minmax(0, 2.25fr);
    gap: clamp(30px, 7vw, 110px);
    padding: var(--section-space) var(--page-pad);
}

.principles__content {
    max-width: 980px;
}

.principles h2,
.components h2,
.specs h2 {
    margin: 0;
    font-family: var(--serif);
    font-size: clamp(32px, 4.3vw, 66px);
    font-weight: 400;
    line-height: 1.55;
    letter-spacing: 0.07em;
}

.principles__lead {
    width: min(620px, 100%);
    margin: clamp(44px, 7vw, 92px) 0 0 auto;
    color: var(--ink-soft);
    font-size: 14px;
    line-height: 2.15;
}

.principle-list {
    margin: clamp(70px, 9vw, 130px) 0 0;
    border-top: 1px solid var(--line);
}

.principle-list > div {
    display: grid;
    grid-template-columns: 76px 1fr;
    padding: 26px 0;
    border-bottom: 1px solid var(--line);
}

.principle-list dt {
    font-family: var(--serif);
    font-size: 12px;
}

.principle-list dd {
    display: grid;
    grid-template-columns: minmax(150px, 0.55fr) minmax(0, 1.45fr);
    gap: 30px;
    margin: 0;
}

.principle-list strong {
    font-family: var(--serif);
    font-size: 18px;
    font-weight: 400;
    letter-spacing: 0.08em;
}

.principle-list span {
    color: var(--ink-soft);
    font-size: 13px;
}

.layout-study {
    padding: var(--section-space) 0;
    color: var(--paper);
    background: #333732;
}

.layout-study__heading {
    display: grid;
    grid-template-columns: minmax(160px, 0.75fr) minmax(0, 2.25fr);
    gap: clamp(30px, 7vw, 110px);
    padding: 0 var(--page-pad) clamp(70px, 9vw, 130px);
}

.layout-study__heading h2 {
    margin: 0;
    font-family: var(--serif);
    font-size: clamp(34px, 5vw, 74px);
    font-weight: 400;
    letter-spacing: 0.08em;
}

.feature-story {
    margin: 0;
}

.feature-story__image-wrap {
    height: clamp(440px, 69vw, 900px);
    overflow: hidden;
}

.feature-story__image-wrap img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: saturate(0.58) contrast(0.92) brightness(0.76) sepia(0.07);
    transition: transform 1.2s cubic-bezier(0.22, 1, 0.36, 1), filter 1.2s ease;
}

.feature-story:hover img {
    filter: saturate(0.7) contrast(0.95) brightness(0.8);
    transform: scale(1.018);
}

.feature-story figcaption {
    display: grid;
    grid-template-columns: 0.5fr 0.9fr 1.7fr 1.2fr;
    gap: clamp(20px, 3vw, 48px);
    align-items: start;
    padding: 42px var(--page-pad) 0;
}

.feature-story__number,
.feature-story__meta {
    font-size: 10px;
    letter-spacing: 0.15em;
}

.feature-story__meta {
    margin: 0;
}

.feature-story h3 {
    margin: -8px 0 0;
    font-family: var(--serif);
    font-size: clamp(24px, 2.7vw, 40px);
    font-weight: 400;
    line-height: 1.75;
    letter-spacing: 0.07em;
}

.feature-story figcaption > p:last-of-type {
    margin: 0;
    color: rgba(242, 241, 233, 0.7);
    font-size: 13px;
    line-height: 2;
}

.text-link {
    grid-column: 4;
    display: flex;
    justify-content: space-between;
    margin-top: 20px;
    padding: 13px 0;
    border-bottom: 1px solid rgba(242, 241, 233, 0.45);
    color: var(--paper);
    font-size: 11px;
}

.text-link span {
    transition: transform 0.45s ease;
}

.text-link:hover span,
.text-link:focus-visible span {
    transform: translateX(8px);
}

.layout-notes {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    margin: clamp(90px, 12vw, 180px) var(--page-pad) 0;
    border-top: 1px solid rgba(242, 241, 233, 0.2);
}

.layout-notes article {
    min-height: 260px;
    padding: 30px clamp(20px, 3vw, 48px) 0 0;
    border-right: 1px solid rgba(242, 241, 233, 0.2);
}

.layout-notes article + article {
    padding-left: clamp(20px, 3vw, 48px);
}

.layout-notes article:last-child {
    border-right: 0;
}

.layout-notes__label,
.component-card__label {
    font-size: 9px;
    letter-spacing: 0.18em;
}

.layout-notes h3 {
    margin: 54px 0 18px;
    font-family: var(--serif);
    font-size: 22px;
    font-weight: 400;
}

.layout-notes p {
    max-width: 340px;
    margin: 0;
    color: rgba(242, 241, 233, 0.65);
    font-size: 12px;
}

.components,
.specs {
    padding: var(--section-space) var(--page-pad);
}

.components__intro,
.specs__header {
    display: grid;
    grid-template-columns: minmax(160px, 0.75fr) minmax(0, 2.25fr);
    gap: clamp(30px, 7vw, 110px);
}

.component-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin-top: clamp(76px, 10vw, 150px);
    border-top: 1px solid var(--line);
    border-left: 1px solid var(--line);
}

.component-card {
    position: relative;
    min-height: 440px;
    padding: clamp(28px, 4vw, 58px);
    overflow: hidden;
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.component-card > p:last-child {
    position: absolute;
    right: clamp(28px, 4vw, 58px);
    bottom: 34px;
    width: min(390px, calc(100% - 56px));
    margin: 0;
    color: var(--ink-soft);
    font-size: 12px;
}

.component-card blockquote {
    margin: 74px 0 0;
    font-family: var(--serif);
    font-size: clamp(27px, 3.2vw, 48px);
    line-height: 1.8;
    letter-spacing: 0.08em;
}

.vertical-note {
    position: absolute !important;
    top: 50px;
    right: 30px !important;
    bottom: auto !important;
    width: auto !important;
    color: var(--ink) !important;
    font-family: var(--serif);
    font-size: 12px !important;
    letter-spacing: 0.28em;
    writing-mode: vertical-rl;
}

.component-card--navigation {
    background: var(--paper-deep);
}

.nav-demo {
    display: grid;
    grid-template-columns: 1fr repeat(3, auto) auto;
    gap: clamp(12px, 2vw, 30px);
    align-items: center;
    margin-top: 92px;
    padding: 18px 20px;
    border-top: 1px solid var(--ink);
    border-bottom: 1px solid var(--ink);
    font-size: 11px;
}

.nav-demo__logo {
    font-family: var(--serif);
    font-size: 20px;
}

.nav-demo button {
    padding: 10px 16px;
    border: 1px solid var(--wood);
    border-radius: 0;
    color: var(--paper);
    background: var(--wood);
    cursor: pointer;
}

.motion-demo {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 120px;
    padding: 26px 0;
    border-bottom: 1px solid var(--ink);
    font-family: var(--serif);
    font-size: clamp(20px, 3vw, 38px);
    letter-spacing: 0.12em;
}

.motion-demo i {
    position: relative;
    display: block;
    width: 86px;
    height: 1px;
    background: var(--ink);
    transition: width 0.6s ease;
}

.motion-demo i::after {
    position: absolute;
    top: -3px;
    right: 0;
    width: 7px;
    height: 7px;
    border-top: 1px solid var(--ink);
    border-right: 1px solid var(--ink);
    content: "";
    transform: rotate(45deg);
}

.motion-demo:hover i,
.motion-demo:focus-visible i {
    width: 118px;
}

.component-card--tone {
    padding: 0;
    color: var(--paper);
    background: var(--wood);
}

.component-card--tone .component-card__label {
    position: absolute;
    z-index: 2;
    top: clamp(28px, 4vw, 58px);
    left: clamp(28px, 4vw, 58px);
    padding: 6px 10px;
    color: var(--paper);
    background: rgba(37, 32, 28, 0.48);
}

.component-card--tone > p:last-child {
    z-index: 2;
    color: rgba(242, 241, 233, 0.85);
    text-shadow: 0 1px 8px rgba(0, 0, 0, 0.35);
}

.tone-preview,
.tone-preview img {
    width: 100%;
    height: 100%;
}

.tone-preview img {
    object-fit: cover;
    filter: saturate(0.56) contrast(0.86) brightness(0.72) sepia(0.12);
    transition: filter 0.8s ease, transform 0.8s ease;
}

.component-card--tone:hover img {
    filter: saturate(0.72) contrast(0.9) brightness(0.76) sepia(0.06);
    transform: scale(1.015);
}

.specs {
    background: #e5e3da;
}

.specs__grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin-top: clamp(76px, 10vw, 150px);
    border-top: 1px solid var(--line);
    border-left: 1px solid var(--line);
}

.spec-block {
    min-height: 430px;
    padding: clamp(28px, 4vw, 58px);
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.spec-block h3 {
    margin: 0 0 54px;
    font-family: var(--serif);
    font-size: 19px;
    font-weight: 400;
}

.swatches {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
}

.swatches > div {
    display: grid;
    gap: 8px;
}

.swatches span {
    width: 100%;
    aspect-ratio: 1;
    border: 1px solid rgba(61, 61, 59, 0.12);
    background: var(--swatch);
}

.swatches code,
.swatches small,
.type-specimens code,
.space-list code {
    font-family: "Courier New", monospace;
    font-size: 10px;
}

.swatches small {
    color: var(--ink-soft);
}

.type-specimens {
    display: grid;
    gap: 28px;
}

.type-specimens > div {
    display: grid;
    grid-template-columns: 70px 1fr auto;
    gap: 20px;
    align-items: baseline;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--line);
}

.type-specimens span {
    font-size: 10px;
    text-transform: uppercase;
}

.type-specimens p {
    margin: 0;
    font-family: var(--serif);
    font-size: clamp(20px, 2.6vw, 36px);
}

.space-list {
    display: grid;
    gap: 16px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.space-list li {
    display: grid;
    grid-template-columns: 38px 1fr 50px;
    gap: 16px;
    align-items: center;
}

.space-list span {
    font-size: 9px;
}

.space-list i {
    display: block;
    width: var(--space);
    height: 8px;
    background: var(--wood);
}

.rule-columns {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.rule-columns > div > span {
    display: block;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--line);
    font-size: 10px;
    letter-spacing: 0.18em;
}

.rule-columns ul {
    margin: 20px 0 0;
    padding: 0;
    list-style: none;
}

.rule-columns li {
    position: relative;
    padding: 7px 0 7px 18px;
    color: var(--ink-soft);
    font-size: 12px;
}

.rule-columns li::before {
    position: absolute;
    top: 18px;
    left: 0;
    width: 6px;
    height: 1px;
    background: var(--ink);
    content: "";
}

.reference-footer {
    display: grid;
    grid-template-columns: 1fr 1.4fr auto;
    gap: 40px;
    align-items: end;
    padding: 62px var(--page-pad);
    color: rgba(242, 241, 233, 0.72);
    background: #2d2f2b;
    font-size: 11px;
}

.reference-footer p {
    margin: 0;
}

.reference-footer > div p {
    color: var(--paper);
    font-family: var(--serif);
    font-size: 18px;
    letter-spacing: 0.16em;
}

.reference-footer > div span {
    font-size: 9px;
}

.reference-footer a {
    color: var(--paper);
    white-space: nowrap;
}

@keyframes hero-breathe {
    from { transform: scale(1.01); }
    to { transform: scale(1.045); }
}

@keyframes scroll-line {
    0% { transform: translateY(-120%); }
    55%, 100% { transform: translateY(190%); }
}

@media (max-width: 960px) {
    .reference-header {
        grid-template-columns: 1fr auto;
    }

    .reference-nav {
        display: none;
    }

    .principles,
    .layout-study__heading,
    .components__intro,
    .specs__header {
        grid-template-columns: 1fr;
    }

    .section-index {
        margin-bottom: 32px;
    }

    .feature-story figcaption {
        grid-template-columns: 0.45fr 1fr 2fr;
    }

    .feature-story figcaption > p:last-of-type,
    .text-link {
        grid-column: 3;
    }

    .component-grid,
    .specs__grid {
        grid-template-columns: 1fr;
    }

    .reference-footer {
        grid-template-columns: 1fr 1fr;
    }

    .reference-footer > a {
        grid-column: 2;
    }
}

@media (max-width: 680px) {
    :root {
        --page-pad: 20px;
        --section-space: 92px;
    }

    body {
        font-size: 14px;
    }

    .reference-header {
        min-height: 60px;
        background: rgba(42, 45, 40, 0.45);
        backdrop-filter: blur(8px);
    }

    .reference-brand {
        font-size: 14px;
    }

    .reference-back {
        font-size: 9px;
    }

    .hero__eyebrow {
        top: 82px;
    }

    .hero__image {
        object-position: 64% center;
    }

    .hero__title-wrap {
        left: var(--page-pad);
        bottom: 180px;
    }

    .hero h1 {
        font-size: clamp(38px, 13vw, 56px);
        line-height: 1.45;
    }

    .hero__note {
        right: var(--page-pad);
        bottom: 38px;
        width: calc(100% - 86px);
        font-size: 11px;
    }

    .hero__scroll {
        bottom: 34px;
    }

    .principles h2,
    .components h2,
    .specs h2 {
        line-height: 1.5;
    }

    .principles__lead {
        margin-top: 40px;
    }

    .principle-list > div {
        grid-template-columns: 42px 1fr;
    }

    .principle-list dd {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .feature-story__image-wrap {
        height: 74svh;
    }

    .feature-story__image-wrap img {
        object-position: 62% center;
    }

    .feature-story figcaption {
        grid-template-columns: 1fr 2fr;
        padding-top: 28px;
    }

    .feature-story h3,
    .feature-story figcaption > p:last-of-type,
    .text-link {
        grid-column: 1 / -1;
    }

    .feature-story h3 {
        margin-top: 18px;
    }

    .layout-notes {
        grid-template-columns: 1fr;
    }

    .layout-notes article,
    .layout-notes article + article {
        min-height: 0;
        padding: 28px 0 40px;
        border-right: 0;
        border-bottom: 1px solid rgba(242, 241, 233, 0.2);
    }

    .layout-notes h3 {
        margin-top: 26px;
    }

    .component-card,
    .spec-block {
        min-height: 390px;
    }

    .component-card blockquote {
        margin-top: 60px;
        font-size: 25px;
    }

    .nav-demo {
        grid-template-columns: 1fr auto;
        gap: 14px;
        margin-top: 58px;
    }

    .nav-demo a {
        display: none;
    }

    .motion-demo {
        margin-top: 92px;
        font-size: 20px;
    }

    .swatches {
        grid-template-columns: repeat(2, 1fr);
        gap: 24px 14px;
    }

    .type-specimens > div {
        grid-template-columns: 1fr;
        gap: 4px;
    }

    .rule-columns {
        grid-template-columns: 1fr;
    }

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

    .reference-footer > a {
        grid-column: 1;
    }
}

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

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}