:root {
    --canvas: #f7f7f4;
    --canvas-soft: #fafaf7;
    --surface-card: #ffffff;
    --surface-strong: #e6e5e0;
    --primary: #f54e00;
    --primary-active: #d04200;
    --ink: #26251e;
    --body: #5a5852;
    --body-strong: #26251e;
    --muted: #807d72;
    --muted-soft: #a09c92;
    --on-primary: #ffffff;
    --hairline: #e6e5e0;
    --hairline-soft: #efeee8;
    --hairline-strong: #cfcdc4;
    --success: #1f8a65;
    --error: #cf2d56;
    --rounded-xs: 4px;
    --rounded-sm: 6px;
    --rounded-md: 8px;
    --rounded-lg: 12px;
    --rounded-xl: 16px;
    --rounded-pill: 9999px;
    --spacing-xxs: 4px;
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-base: 16px;
    --spacing-md: 20px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    --spacing-section: 80px;
    --font-main: 'Inter', system-ui, 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    background-color: var(--canvas);
    color: var(--body);
    font-family: var(--font-main);
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--ink);
    text-decoration: none;
}

a:hover {
    color: var(--primary);
}

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

ul {
    list-style: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.site-nav {
    background-color: var(--canvas);
    border-bottom: 1px solid var(--hairline);
    position: sticky;
    top: 0;
    z-index: 100;
    height: 64px;
    display: flex;
    align-items: center;
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
}

.nav-logo {
    text-decoration: none;
    flex-shrink: 0;
}

.logo-text {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: -0.3px;
    color: var(--ink);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    flex-wrap: nowrap;
}

.nav-link {
    font-size: 14px;
    font-weight: 500;
    line-height: 1.4;
    color: var(--body);
    text-decoration: none;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--rounded-sm);
    border: none;
    background: transparent;
    cursor: pointer;
    transition: color 0.15s ease, background-color 0.15s ease;
    white-space: nowrap;
}

.nav-link:hover,
.nav-link--active {
    color: var(--ink);
    background-color: var(--surface-strong);
}

.nav-dropdown {
    position: relative;
}

.nav-dropdown-toggle {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-arrow {
    font-size: 10px;
    transition: transform 0.2s ease;
}

.nav-dropdown-toggle[aria-expanded="true"] .nav-arrow {
    transform: rotate(180deg);
}

.nav-dropdown-menu {
    display: none;
    position: absolute;
    top: calc(100% + 4px);
    left: 0;
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--rounded-lg);
    padding: var(--spacing-xs);
    min-width: 220px;
    box-shadow: 0 4px 16px rgba(38, 37, 30, 0.08);
    z-index: 200;
}

.nav-dropdown-menu.is-open {
    display: block;
}

.nav-dropdown-menu .nav-link {
    display: block;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--rounded-sm);
}

.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
    border-radius: var(--rounded-sm);
}

.nav-hamburger span {
    display: block;
    width: 22px;
    height: 2px;
    background-color: var(--ink);
    border-radius: 2px;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-main);
    font-size: 14px;
    font-weight: 500;
    line-height: 1;
    text-decoration: none;
    border: none;
    cursor: pointer;
    border-radius: var(--rounded-md);
    padding: 10px 18px;
    height: 40px;
    transition: background-color 0.15s ease, color 0.15s ease;
    white-space: nowrap;
}

.btn--primary {
    background-color: var(--primary);
    color: var(--on-primary);
}

.btn--primary:hover {
    background-color: var(--primary-active);
    color: var(--on-primary);
}

.btn--secondary {
    background-color: var(--surface-card);
    color: var(--ink);
    border: 1px solid var(--hairline-strong);
}

.btn--secondary:hover {
    background-color: var(--surface-strong);
}

.btn--download {
    background-color: var(--ink);
    color: var(--canvas);
    padding: 12px 20px;
    height: 44px;
}

.btn--download:hover {
    background-color: #3a3930;
    color: var(--canvas);
}

.hero {
    background-color: var(--canvas);
    padding: var(--spacing-section) 0 var(--spacing-xxl);
    border-bottom: 1px solid var(--hairline);
}

.hero-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.hero-label {
    display: inline-block;
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    background-color: var(--surface-strong);
    color: var(--ink);
    border-radius: var(--rounded-pill);
    padding: 4px 10px;
    margin-bottom: var(--spacing-lg);
}

.hero-title {
    font-size: 72px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -2.16px;
    color: var(--ink);
    max-width: 800px;
    margin-bottom: var(--spacing-lg);
}

.hero-desc {
    font-size: 18px;
    font-weight: 400;
    line-height: 1.6;
    color: var(--body);
    max-width: 560px;
    margin-bottom: var(--spacing-xl);
}

.hero-image {
    margin-top: var(--spacing-xxl);
    border-radius: var(--rounded-lg);
    overflow: hidden;
    border: 1px solid var(--hairline);
    max-height: 480px;
}

.hero-image img {
    width: 100%;
    height: 480px;
    object-fit: cover;
}

.section {
    padding: var(--spacing-section) 0;
}

.section--alt {
    background-color: var(--canvas-soft);
    border-top: 1px solid var(--hairline);
    border-bottom: 1px solid var(--hairline);
}

.section-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.section-label {
    display: inline-block;
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: var(--spacing-base);
}

.section-title {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--ink);
    margin-bottom: var(--spacing-base);
}

.section-desc {
    font-size: 16px;
    line-height: 1.6;
    color: var(--body);
    max-width: 600px;
    margin-bottom: var(--spacing-xxl);
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

.card {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--rounded-lg);
    padding: var(--spacing-lg);
    transition: border-color 0.15s ease;
}

.card:hover {
    border-color: var(--hairline-strong);
}

.card--article {
    padding: 0;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.card--article .card-image {
    height: 200px;
    overflow: hidden;
}

.card--article .card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.card--article:hover .card-image img {
    transform: scale(1.03);
}

.card--article .card-body {
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.card-category {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: var(--spacing-xs);
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.3;
    color: var(--ink);
    margin-bottom: var(--spacing-xs);
}

.card-excerpt {
    font-size: 14px;
    line-height: 1.5;
    color: var(--body);
    flex: 1;
    margin-bottom: var(--spacing-base);
}

.card-link {
    font-size: 14px;
    font-weight: 500;
    color: var(--ink);
    border-bottom: 1px solid var(--hairline);
    padding-bottom: 2px;
    display: inline-block;
    align-self: flex-start;
}

.card-link:hover {
    color: var(--primary);
    border-color: var(--primary);
}

.card-icon {
    width: 40px;
    height: 40px;
    background-color: var(--canvas);
    border-radius: var(--rounded-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-base);
    font-size: 20px;
}

.card-title--sm {
    font-size: 16px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--ink);
    margin-bottom: var(--spacing-xs);
}

.card-text {
    font-size: 14px;
    line-height: 1.5;
    color: var(--body);
}

.article-header {
    background-color: var(--canvas);
    padding: var(--spacing-xxl) 0;
    border-bottom: 1px solid var(--hairline);
}

.article-header-inner {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.article-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-base);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.article-category {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    background-color: var(--surface-strong);
    color: var(--ink);
    border-radius: var(--rounded-pill);
    padding: 4px 10px;
}

.article-date {
    font-size: 13px;
    color: var(--muted);
}

.article-title {
    font-size: 48px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -1.2px;
    color: var(--ink);
    margin-bottom: var(--spacing-lg);
}

.article-lead {
    font-size: 18px;
    line-height: 1.6;
    color: var(--body);
}

.article-image-hero {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-xxl) var(--spacing-xl) 0;
}

.article-image-hero img {
    width: 100%;
    height: 420px;
    object-fit: cover;
    border-radius: var(--rounded-lg);
    border: 1px solid var(--hairline);
}

.article-body {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-section) var(--spacing-xl);
}

.article-body h2 {
    font-size: 26px;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: -0.325px;
    color: var(--ink);
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-base);
}

.article-body h3 {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--ink);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-xs);
}

.article-body p {
    margin-bottom: var(--spacing-base);
    line-height: 1.7;
    letter-spacing: 0.08px;
}

.article-body ul,
.article-body ol {
    margin-bottom: var(--spacing-base);
    padding-left: var(--spacing-xl);
}

.article-body ul {
    list-style: disc;
}

.article-body ol {
    list-style: decimal;
}

.article-body li {
    margin-bottom: var(--spacing-xs);
    line-height: 1.6;
}

.article-body a {
    color: var(--ink);
    border-bottom: 1px solid var(--hairline-strong);
    padding-bottom: 1px;
}

.article-body a:hover {
    color: var(--primary);
    border-color: var(--primary);
}

.article-body figure {
    margin: var(--spacing-xxl) 0;
}

.article-body figure img {
    width: 100%;
    border-radius: var(--rounded-lg);
    border: 1px solid var(--hairline);
}

.article-body figcaption {
    font-size: 13px;
    color: var(--muted);
    margin-top: var(--spacing-xs);
    text-align: center;
}

.infobox {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-left: 3px solid var(--ink);
    border-radius: 0 var(--rounded-md) var(--rounded-md) 0;
    padding: var(--spacing-lg);
    margin: var(--spacing-xl) 0;
}

.infobox-title {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: var(--spacing-xs);
}

.infobox p {
    margin-bottom: 0;
    font-size: 14px;
    line-height: 1.6;
}

.related-articles {
    background-color: var(--canvas-soft);
    border-top: 1px solid var(--hairline);
    padding: var(--spacing-section) 0;
}

.related-articles-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.contact-section {
    padding: var(--spacing-section) 0;
    background-color: var(--canvas);
}

.contact-inner {
    max-width: 680px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--ink);
    margin-bottom: var(--spacing-xs);
}

.form-input,
.form-textarea {
    width: 100%;
    background-color: var(--surface-card);
    color: var(--ink);
    font-family: var(--font-main);
    font-size: 16px;
    line-height: 1.5;
    border: 1px solid var(--hairline-strong);
    border-radius: var(--rounded-md);
    padding: 12px 16px;
    height: 44px;
    outline: none;
    transition: border-color 0.15s ease;
    -webkit-appearance: none;
}

.form-textarea {
    height: auto;
    min-height: 120px;
    resize: vertical;
}

.form-input:focus,
.form-textarea:focus {
    border-color: var(--ink);
}

.form-input.is-invalid,
.form-textarea.is-invalid {
    border-color: var(--error);
}

.form-error {
    display: none;
    font-size: 13px;
    color: var(--error);
    margin-top: var(--spacing-xxs);
}

.form-error.is-visible {
    display: block;
}

.form-success {
    display: none;
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--rounded-lg);
    padding: var(--spacing-lg);
    text-align: center;
    color: var(--success);
    font-size: 16px;
    margin-top: var(--spacing-base);
}

.form-success.is-visible {
    display: block;
}

.btn--loading {
    position: relative;
    color: transparent;
    pointer-events: none;
}

.btn--loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255,255,255,0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.page-header {
    background-color: var(--canvas);
    padding: var(--spacing-xxl) 0;
    border-bottom: 1px solid var(--hairline);
}

.page-header-inner {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.page-title {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--ink);
    margin-bottom: var(--spacing-base);
}

.page-body {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-section) var(--spacing-xl);
}

.page-body h2 {
    font-size: 22px;
    font-weight: 400;
    line-height: 1.3;
    letter-spacing: -0.11px;
    color: var(--ink);
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-sm);
}

.page-body h3 {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--ink);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-xs);
}

.page-body p {
    margin-bottom: var(--spacing-base);
    line-height: 1.7;
}

.page-body ul,
.page-body ol {
    margin-bottom: var(--spacing-base);
    padding-left: var(--spacing-xl);
}

.page-body ul {
    list-style: disc;
}

.page-body ol {
    list-style: decimal;
}

.page-body li {
    margin-bottom: var(--spacing-xs);
    line-height: 1.6;
}

.page-body a {
    color: var(--ink);
    border-bottom: 1px solid var(--hairline-strong);
}

.page-body a:hover {
    color: var(--primary);
}

.updated-date {
    font-size: 13px;
    color: var(--muted);
    margin-bottom: var(--spacing-base);
}

.cookie-banner {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: var(--surface-card);
    border-top: 1px solid var(--hairline);
    z-index: 9999;
    padding: var(--spacing-lg) 0;
}

.cookie-banner.is-visible {
    display: block;
}

.cookie-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.cookie-text {
    font-size: 14px;
    color: var(--body);
    flex: 1;
    min-width: 260px;
}

.cookie-text a {
    color: var(--ink);
    border-bottom: 1px solid var(--hairline-strong);
}

.cookie-actions {
    display: flex;
    gap: var(--spacing-xs);
    flex-shrink: 0;
}

.site-footer {
    background-color: var(--canvas);
    border-top: 1px solid var(--hairline);
    padding: 64px 0 48px;
}

.footer-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--spacing-xxl);
    margin-bottom: var(--spacing-xxl);
}

.footer-logo {
    font-size: 16px;
    font-weight: 600;
    color: var(--ink);
    text-decoration: none;
    display: inline-block;
    margin-bottom: var(--spacing-sm);
}

.footer-tagline {
    font-size: 14px;
    color: var(--body);
    line-height: 1.5;
}

.footer-heading {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: var(--spacing-base);
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.footer-links a {
    font-size: 14px;
    color: var(--body);
    text-decoration: none;
}

.footer-links a:hover {
    color: var(--ink);
}

.footer-bottom {
    border-top: 1px solid var(--hairline);
    padding-top: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.footer-copy,
.footer-disclaimer {
    font-size: 14px;
    color: var(--muted);
}

.breadcrumb {
    font-size: 13px;
    color: var(--muted);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.breadcrumb a {
    color: var(--muted);
    text-decoration: none;
}

.breadcrumb a:hover {
    color: var(--ink);
}

.breadcrumb-sep {
    color: var(--muted-soft);
}

@media (max-width: 1024px) {
    .hero-title {
        font-size: 56px;
        letter-spacing: -1.4px;
    }

    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }

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

@media (max-width: 768px) {
    .container,
    .nav-inner,
    .hero-inner,
    .section-inner,
    .footer-inner,
    .contact-inner,
    .page-header-inner,
    .page-body,
    .article-header-inner,
    .article-body,
    .article-image-hero,
    .related-articles-inner {
        padding-left: var(--spacing-base);
        padding-right: var(--spacing-base);
    }

    .nav-hamburger {
        display: flex;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background-color: var(--surface-card);
        border-top: 1px solid var(--hairline);
        border-bottom: 1px solid var(--hairline);
        flex-direction: column;
        align-items: stretch;
        padding: var(--spacing-xs);
        gap: 2px;
        z-index: 100;
    }

    .nav-menu.is-open {
        display: flex;
    }

    .nav-dropdown-menu {
        position: static;
        box-shadow: none;
        background-color: var(--canvas-soft);
        border: none;
        border-radius: var(--rounded-sm);
        padding: 0 0 0 var(--spacing-base);
        min-width: auto;
    }

    .hero-title {
        font-size: 32px;
        letter-spacing: -0.8px;
    }

    .hero-desc {
        font-size: 16px;
    }

    .article-title {
        font-size: 32px;
        letter-spacing: -0.8px;
    }

    .section-title {
        font-size: 26px;
        letter-spacing: -0.325px;
    }

    .grid-3,
    .grid-2 {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }

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

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

    .hero-image img {
        height: 240px;
    }

    .article-image-hero img {
        height: 240px;
    }

    .card--article .card-image {
        height: 180px;
    }
}

@media (max-width: 640px) {
    .section {
        padding: var(--spacing-xxl) 0;
    }

    .hero {
        padding: var(--spacing-xxl) 0;
    }
}