:root {
    --bg: #f1ece4;
    --bg-strong: #e5ddd1;
    --panel: rgba(255, 255, 255, 0.58);
    --panel-strong: rgba(255, 255, 255, 0.74);
    --text: #111216;
    --muted: #5d5954;
    --line: rgba(17, 18, 22, 0.12);
    --line-strong: rgba(17, 18, 22, 0.24);
    --accent: #1f46ff;
    --accent-soft: rgba(31, 70, 255, 0.1);
    --accent-2: #8d59ff;
    --shadow: 0 24px 70px rgba(21, 18, 14, 0.08);
    --shell: min(1180px, calc(100vw - 56px));
    --display: "Inter Tight", "Noto Sans SC", sans-serif;
    --body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --serif: "Noto Serif SC", serif;
    --mono: "IBM Plex Mono", monospace;
    --radius-sm: 6px;
    --radius-md: 10px;
}

:root[data-theme="dark"] {
    --bg: #0c0e12;
    --bg-strong: #141821;
    --panel: rgba(255, 255, 255, 0.04);
    --panel-strong: rgba(255, 255, 255, 0.08);
    --text: #ece8e1;
    --muted: #9c978f;
    --line: rgba(255, 255, 255, 0.1);
    --line-strong: rgba(255, 255, 255, 0.22);
    --accent: #8ca2ff;
    --accent-soft: rgba(140, 162, 255, 0.12);
    --accent-2: #c39cff;
    --shadow: 0 30px 80px rgba(0, 0, 0, 0.34);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: var(--body);
    color: var(--text);
    background:
        radial-gradient(circle at 12% 0%, rgba(31, 70, 255, 0.08), transparent 36%),
        radial-gradient(circle at 100% 20%, rgba(141, 89, 255, 0.1), transparent 32%),
        linear-gradient(180deg, var(--bg), var(--bg-strong));
    transition: background-color 240ms ease, color 240ms ease;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: -2;
    background-image:
        linear-gradient(var(--line) 1px, transparent 1px),
        linear-gradient(90deg, var(--line) 1px, transparent 1px);
    background-size: 36px 36px;
    mask-image: radial-gradient(circle at center, black 44%, transparent 100%);
    opacity: 0.45;
}

::selection {
    background: var(--accent);
    color: #fff;
}

button,
input,
a {
    font: inherit;
}

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

.shell {
    width: var(--shell);
    margin: 0 auto;
}

.page-noise,
.page-glow {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: -1;
}

.page-noise {
    background-image: radial-gradient(rgba(17, 18, 22, 0.04) 0.6px, transparent 0.6px);
    background-size: 8px 8px;
    opacity: 0.22;
    mix-blend-mode: multiply;
}

:root[data-theme="dark"] .page-noise {
    mix-blend-mode: screen;
    opacity: 0.09;
}

.page-glow {
    background:
        radial-gradient(600px 320px at 80% 8%, rgba(31, 70, 255, 0.14), transparent 60%),
        radial-gradient(480px 260px at 16% 28%, rgba(141, 89, 255, 0.12), transparent 62%);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    backdrop-filter: blur(18px);
    background: color-mix(in srgb, var(--bg) 76%, transparent);
    border-bottom: 1px solid var(--line);
}

.header-inner {
    min-height: 72px;
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: 18px;
    align-items: center;
}

.brand {
    display: inline-flex;
    align-items: baseline;
    gap: 12px;
    font-family: var(--display);
}

.brand-code {
    font-family: var(--mono);
    font-size: 0.78rem;
    letter-spacing: 0.16em;
    color: var(--accent);
}

.brand-name {
    font-size: 1.05rem;
    font-weight: 600;
    letter-spacing: -0.03em;
}

.header-nav {
    display: inline-flex;
    gap: 18px;
    align-items: center;
}

.nav-link {
    position: relative;
    font-size: 0.95rem;
    color: var(--muted);
    padding: 6px 0;
    transition: color 200ms ease;
}

.nav-link::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 1px;
    background: var(--text);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 220ms ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text);
}

.nav-link:hover::after,
.nav-link.active::after {
    transform: scaleX(1);
}

.menu-toggle,
.theme-toggle,
.reader-close {
    border: 1px solid var(--line);
    background: var(--panel);
    color: var(--text);
}

.theme-toggle,
.reader-close {
    min-width: 64px;
    height: 38px;
    padding: 0 14px;
    cursor: pointer;
    transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.theme-toggle:hover,
.reader-close:hover {
    transform: translateY(-1px);
    border-color: var(--line-strong);
}

.menu-toggle {
    display: none;
    width: 40px;
    height: 40px;
    padding: 10px;
    cursor: pointer;
    align-items: center;
    justify-content: center;
    gap: 5px;
}

.menu-toggle span {
    display: block;
    width: 100%;
    height: 1px;
    background: currentColor;
}

.hero {
    padding: 52px 0 32px;
}

.hero-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.18fr) minmax(320px, 0.82fr);
    gap: 52px;
    align-items: start;
}

.section-kicker {
    margin: 0 0 14px;
    font-family: var(--mono);
    font-size: 0.74rem;
    letter-spacing: 0.18em;
    color: var(--accent);
}

.hero h1 {
    margin: 0;
    font-family: var(--display);
    font-size: clamp(3.2rem, 10vw, 7.6rem);
    line-height: 0.92;
    letter-spacing: -0.07em;
    max-width: 8ch;
}

.hero-summary {
    max-width: 36ch;
    margin: 20px 0 0;
    font-size: clamp(1rem, 1.6vw, 1.16rem);
    line-height: 1.9;
    color: var(--muted);
}

.hero-actions {
    margin-top: 28px;
    display: flex;
    gap: 22px;
    flex-wrap: wrap;
}

.action-link {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 12px;
    font-size: 0.95rem;
    color: var(--muted);
    transition: color 200ms ease;
}

.action-link::after {
    content: "↗";
    font-family: var(--mono);
    font-size: 0.8rem;
}

.action-link:hover,
.action-link-primary {
    color: var(--text);
}

.hero-metrics {
    margin-top: 48px;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    padding: 18px 0;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.hero-metrics article {
    min-width: 0;
}

.metric-label {
    display: block;
    margin-bottom: 12px;
    font-family: var(--mono);
    font-size: 0.72rem;
    letter-spacing: 0.14em;
    color: var(--muted);
}

.hero-metrics strong {
    font-family: var(--display);
    font-size: clamp(1.65rem, 4vw, 2.4rem);
    letter-spacing: -0.05em;
}

.hero-rail {
    display: grid;
    gap: 18px;
}

.hero-feature,
.selected-primary .feature-panel {
    position: relative;
    overflow: hidden;
    padding: 28px;
    clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
    border: 1px solid var(--line-strong);
    background:
        linear-gradient(180deg, color-mix(in srgb, var(--panel-strong) 92%, transparent), color-mix(in srgb, var(--panel) 90%, transparent));
    box-shadow: var(--shadow);
}

.hero-feature::before,
.selected-primary .feature-panel::before {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, transparent 48%, var(--accent) 50%, var(--accent-2) 100%);
    opacity: 0.85;
}

.feature-tag {
    display: inline-block;
    margin-bottom: 18px;
    font-family: var(--mono);
    font-size: 0.72rem;
    letter-spacing: 0.14em;
    color: var(--accent);
}

.feature-title {
    margin: 0;
    font-family: var(--display);
    font-size: clamp(1.6rem, 3vw, 2.5rem);
    line-height: 1.05;
    letter-spacing: -0.05em;
}

.feature-excerpt {
    margin: 16px 0 0;
    line-height: 1.9;
    color: var(--muted);
}

.feature-foot {
    margin-top: 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
}

.feature-foot time,
.headline-meta,
.archive-meta,
.archive-side,
.band-count,
.reader-meta {
    font-family: var(--mono);
    font-size: 0.78rem;
    letter-spacing: 0.04em;
    color: var(--muted);
}

.text-button {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    border: 0;
    padding: 0;
    background: transparent;
    color: var(--text);
    cursor: pointer;
}

.text-button::after {
    content: "→";
    transition: transform 180ms ease;
}

.text-button:hover::after {
    transform: translateX(4px);
}

.hero-note {
    display: grid;
    gap: 12px;
    padding-top: 8px;
    border-top: 1px solid var(--line);
    color: var(--muted);
    line-height: 1.8;
}

.section {
    padding: 40px 0 56px;
}

.section-head {
    display: grid;
    grid-template-columns: auto 1fr;
    align-items: end;
    gap: 20px;
    margin-bottom: 24px;
}

.section-head h2 {
    margin: 6px 0 0;
    font-family: var(--display);
    font-size: clamp(1.8rem, 4vw, 3rem);
    letter-spacing: -0.05em;
}

.section-index {
    font-family: var(--mono);
    font-size: 0.8rem;
    letter-spacing: 0.16em;
    color: var(--muted);
    padding-bottom: 14px;
}

.section-head-archive {
    grid-template-columns: 1fr auto;
    align-items: end;
}

.selected-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.02fr) minmax(320px, 0.98fr);
    gap: 34px;
}

.selected-list,
.archive-list {
    border-top: 1px solid var(--line);
}

.headline-item,
.archive-row {
    position: relative;
    display: grid;
    gap: 18px;
    padding: 18px 0;
    border-bottom: 1px solid var(--line);
    transition: transform 180ms ease, background 180ms ease;
}

.headline-item {
    grid-template-columns: 72px minmax(0, 1fr);
}

.headline-item:hover,
.archive-row:hover {
    transform: translateX(6px);
}

.headline-open,
.archive-open {
    border: 0;
    padding: 0;
    background: transparent;
    color: inherit;
    cursor: pointer;
    text-align: left;
}

.headline-open {
    display: grid;
    gap: 8px;
}

.headline-title {
    font-family: var(--display);
    font-size: 1.18rem;
    line-height: 1.35;
    letter-spacing: -0.03em;
}

.spectrum-grid {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.band {
    padding: 24px 18px 28px 0;
    border-right: 1px solid var(--line);
}

.band:last-child {
    border-right: 0;
}

.band-index {
    margin: 0 0 22px;
    font-family: var(--mono);
    font-size: 0.72rem;
    letter-spacing: 0.16em;
    color: var(--muted);
}

.band h3 {
    margin: 0;
    font-family: var(--display);
    font-size: 1.4rem;
    letter-spacing: -0.04em;
}

.band p {
    margin: 12px 0 0;
    color: var(--muted);
    line-height: 1.8;
}

.band-count {
    margin-top: 18px;
    display: inline-block;
    color: var(--accent);
}

.search-box {
    display: inline-flex;
    align-items: center;
    gap: 14px;
    padding: 10px 14px;
    border: 1px solid var(--line);
    background: var(--panel);
    min-width: min(100%, 300px);
}

.search-box span {
    font-family: var(--mono);
    font-size: 0.74rem;
    letter-spacing: 0.16em;
    color: var(--muted);
}

.search-box input {
    width: 220px;
    border: 0;
    outline: none;
    background: transparent;
    color: var(--text);
}

.filter-tabs {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    margin: 0 0 10px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--line);
}

.filter-btn {
    border: 0;
    padding: 0;
    background: transparent;
    color: var(--muted);
    cursor: pointer;
    font-family: var(--mono);
    font-size: 0.78rem;
    letter-spacing: 0.12em;
    transition: color 180ms ease;
}

.filter-btn.active,
.filter-btn:hover {
    color: var(--text);
}

.archive-row {
    grid-template-columns: 120px minmax(0, 1fr) 120px;
    align-items: start;
}

.archive-main h3 {
    margin: 0;
    font-family: var(--display);
    font-size: clamp(1.15rem, 2vw, 1.48rem);
    letter-spacing: -0.04em;
}

.archive-main p {
    margin: 10px 0 0;
    color: var(--muted);
    line-height: 1.8;
}

.archive-side {
    display: grid;
    justify-items: end;
    gap: 14px;
    text-align: right;
}

.archive-open {
    font-family: var(--mono);
    font-size: 0.78rem;
    letter-spacing: 0.12em;
}

.archive-open::after {
    content: " ↗";
}

.empty-state {
    padding: 32px 0;
    color: var(--muted);
    line-height: 1.8;
}

.method-grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr);
    gap: 42px;
    padding-top: 24px;
    border-top: 1px solid var(--line);
}

.method-lead h2 {
    margin: 8px 0 0;
    font-family: var(--display);
    font-size: clamp(2rem, 5vw, 4.2rem);
    line-height: 0.98;
    letter-spacing: -0.06em;
    max-width: 8ch;
}

.method-quote {
    margin: 22px 0 0;
    font-family: var(--serif);
    font-size: clamp(1.1rem, 2vw, 1.4rem);
    line-height: 1.9;
}

.method-copy {
    padding-top: 10px;
    color: var(--muted);
    line-height: 1.9;
}

.method-copy ul {
    margin: 18px 0 0;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 12px;
}

.method-copy li {
    padding-top: 12px;
    border-top: 1px solid var(--line);
}

.site-footer {
    padding: 22px 0 28px;
    border-top: 1px solid var(--line);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    color: var(--muted);
    font-size: 0.92rem;
}

.footer-meta,
.footer-links {
    display: flex;
    align-items: center;
    gap: 18px;
    flex-wrap: wrap;
}

.footer-meta p {
    margin: 0;
}

.footer-record,
.footer-link {
    position: relative;
    transition: color 180ms ease;
}

.footer-record::after,
.footer-link::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 100%;
    height: 1px;
    background: currentColor;
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 180ms ease;
    opacity: 0.7;
}

.footer-record:hover,
.footer-link:hover {
    color: var(--text);
}

.footer-record:hover::after,
.footer-link:hover::after {
    transform: scaleX(1);
}

.reader {
    position: fixed;
    inset: 0;
    display: grid;
    place-items: center;
    padding: 16px;
    z-index: 60;
    opacity: 0;
    visibility: hidden;
    transition: opacity 220ms ease, visibility 220ms ease;
}

.reader.active {
    opacity: 1;
    visibility: visible;
}

.reader-backdrop {
    position: absolute;
    inset: 0;
    border: 0;
    background: rgba(10, 11, 14, 0.62);
    backdrop-filter: blur(10px);
    cursor: pointer;
}

.reader-panel {
    position: relative;
    width: min(1080px, calc(100vw - 24px));
    height: min(88vh, 980px);
    display: grid;
    grid-template-rows: auto auto 1fr;
    border: 1px solid var(--line-strong);
    background: color-mix(in srgb, var(--bg) 92%, transparent);
    box-shadow: var(--shadow);
}

.reader-progress {
    height: 2px;
    background: var(--line);
}

.reader-progress span {
    display: block;
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.reader-head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 20px;
    padding: 22px 24px 18px;
    border-bottom: 1px solid var(--line);
}

.reader-head-main {
    min-width: 0;
}

.reader-head h3 {
    margin: 6px 0 0;
    font-family: var(--display);
    font-size: clamp(1.45rem, 2.5vw, 2.1rem);
    letter-spacing: -0.05em;
}

.reader-body {
    overflow: auto;
    padding: 26px 24px 34px;
}

.markdown-body {
    max-width: 760px;
    margin: 0 auto;
    color: var(--text);
    line-height: 1.95;
    word-break: break-word;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4 {
    font-family: var(--display);
    line-height: 1.2;
    letter-spacing: -0.04em;
}

.markdown-body h1 {
    font-size: clamp(2rem, 4vw, 3rem);
}

.markdown-body p {
    margin: 0 0 1.05em;
}

.markdown-body blockquote {
    margin: 1.2em 0;
    padding: 0.7em 0 0.7em 1em;
    border-left: 2px solid var(--accent);
    color: var(--muted);
}

.markdown-body code {
    font-family: var(--mono);
    font-size: 0.92em;
    background: var(--accent-soft);
    padding: 0.12em 0.34em;
}

.markdown-body pre {
    padding: 14px;
    overflow: auto;
    border: 1px solid var(--line);
    background: var(--panel);
}

.markdown-body img {
    max-width: 100%;
    height: auto;
}

.reveal {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 700ms cubic-bezier(0.2, 0.9, 0.2, 1), transform 700ms cubic-bezier(0.2, 0.9, 0.2, 1);
    transition-delay: var(--delay, 0ms);
}

.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 980px) {
    .hero-grid,
    .selected-layout,
    .method-grid {
        grid-template-columns: 1fr;
    }

    .spectrum-grid {
        grid-template-columns: 1fr 1fr;
        gap: 0;
    }

    .band:nth-child(2n) {
        border-right: 0;
        padding-right: 0;
        padding-left: 18px;
    }

    .band:nth-child(2n+1) {
        padding-right: 18px;
    }

    .archive-row {
        grid-template-columns: 100px 1fr;
    }

    .archive-side {
        grid-column: 2;
        justify-items: start;
        text-align: left;
    }
}

@media (max-width: 780px) {
    .shell {
        width: min(100vw - 28px, 1180px);
    }

    .header-inner {
        grid-template-columns: 1fr auto auto;
    }

    .menu-toggle {
        display: inline-flex;
    }

    .header-nav {
        position: absolute;
        top: calc(100% + 8px);
        right: 14px;
        min-width: 180px;
        padding: 12px;
        flex-direction: column;
        align-items: stretch;
        border: 1px solid var(--line);
        background: color-mix(in srgb, var(--bg) 92%, transparent);
        opacity: 0;
        pointer-events: none;
        transform: translateY(-6px);
        transition: opacity 180ms ease, transform 180ms ease;
    }

    .header-nav.open {
        opacity: 1;
        pointer-events: auto;
        transform: translateY(0);
    }

    .hero {
        padding-top: 28px;
    }

    .hero-metrics {
        grid-template-columns: 1fr;
        gap: 14px;
    }

    .section-head,
    .section-head-archive {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .section-index {
        padding-bottom: 0;
    }

    .search-box {
        min-width: 100%;
    }

    .search-box input {
        width: 100%;
    }

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

    .band,
    .band:nth-child(2n),
    .band:nth-child(2n+1) {
        padding-left: 0;
        padding-right: 0;
        border-right: 0;
        border-bottom: 1px solid var(--line);
    }

    .archive-row,
    .headline-item {
        grid-template-columns: 1fr;
    }

    .reader-panel {
        height: min(92vh, 980px);
    }

    .reader-head {
        padding: 18px 18px 16px;
    }

    .reader-body {
        padding: 20px 18px 28px;
    }

    .footer-inner {
        flex-direction: column;
        align-items: flex-start;
    }

    .footer-meta,
    .footer-links {
        align-items: flex-start;
        gap: 10px 16px;
        flex-direction: column;
    }
}

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

    *, *::before, *::after {
        animation: none !important;
        transition: none !important;
    }
}