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

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

html { scroll-behavior: smooth; }
body { background: var(--canvas); color: var(--body); font-family: var(--font-sans); font-size: 16px; line-height: 1.5; }

a { color: inherit; text-decoration: none; }
a:hover { color: var(--ink); }
img { display: block; max-width: 100%; height: auto; }
ul { list-style: none; }

.rh-container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

.rh-nav {
    position: sticky; top: 0; z-index: 100;
    background: var(--canvas);
    border-bottom: 1px solid var(--hairline);
    height: 64px;
}
.rh-nav__inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px;
}
.rh-nav__logo {
    font-family: var(--font-sans); font-size: 18px; font-weight: 600;
    color: var(--ink); letter-spacing: -0.3px;
}
.rh-nav__menu {
    display: flex; gap: 32px; align-items: center;
}
.rh-nav__menu a {
    font-size: 14px; font-weight: 500; color: var(--body); line-height: 1.4;
    transition: color 0.15s;
}
.rh-nav__menu a:hover,
.rh-nav__menu a[aria-current="page"] { color: var(--ink); }
.rh-nav__burger {
    display: none; flex-direction: column; gap: 5px; background: none; border: none;
    cursor: pointer; padding: 4px;
}
.rh-nav__burger span {
    display: block; width: 22px; height: 2px; background: var(--ink); border-radius: 2px;
    transition: transform 0.2s, opacity 0.2s;
}

.rh-hero {
    padding: 80px 0 64px;
    border-bottom: 1px solid var(--hairline);
}
.rh-hero__label {
    display: inline-block; font-size: 11px; font-weight: 600; letter-spacing: 0.88px;
    text-transform: uppercase; color: var(--muted);
    background: var(--surface-strong); border-radius: var(--rounded-pill);
    padding: 4px 10px; margin-bottom: 24px;
}
.rh-hero__title {
    font-size: 56px; font-weight: 400; line-height: 1.1; letter-spacing: -1.5px;
    color: var(--ink); max-width: 760px; margin-bottom: 20px;
}
.rh-hero__lead {
    font-size: 18px; color: var(--body); max-width: 600px; line-height: 1.6;
    margin-bottom: 40px;
}
.rh-hero__img {
    width: 100%; max-height: 480px; object-fit: cover;
    border-radius: var(--rounded-lg); border: 1px solid var(--hairline);
    margin-top: 48px;
}

.rh-section { padding: 80px 0; }
.rh-section--alt { background: var(--canvas-soft); }
.rh-section__label {
    font-size: 11px; font-weight: 600; letter-spacing: 0.88px; text-transform: uppercase;
    color: var(--muted); margin-bottom: 12px;
}
.rh-section__title {
    font-size: 36px; font-weight: 400; line-height: 1.2; letter-spacing: -0.72px;
    color: var(--ink); margin-bottom: 16px;
}
.rh-section__lead {
    font-size: 16px; color: var(--body); max-width: 580px; margin-bottom: 48px;
}

.rh-grid { display: grid; gap: 24px; }
.rh-grid--3 { grid-template-columns: repeat(3, 1fr); }
.rh-grid--2 { grid-template-columns: repeat(2, 1fr); }

.rh-card {
    background: var(--surface-card); border: 1px solid var(--hairline);
    border-radius: var(--rounded-lg); overflow: hidden;
}
.rh-card__img { width: 100%; height: 200px; object-fit: cover; }
.rh-card__body { padding: 24px; }
.rh-card__label {
    font-size: 11px; font-weight: 600; letter-spacing: 0.88px; text-transform: uppercase;
    color: var(--muted); margin-bottom: 8px;
}
.rh-card__title {
    font-size: 18px; font-weight: 600; color: var(--ink); line-height: 1.4;
    margin-bottom: 10px;
}
.rh-card__text { font-size: 14px; color: var(--body); line-height: 1.5; margin-bottom: 16px; }
.rh-card__link {
    font-size: 14px; font-weight: 500; color: var(--primary);
}
.rh-card__link:hover { color: var(--primary-active); }

.rh-article-grid { display: grid; grid-template-columns: 1fr 320px; gap: 48px; }

.rh-article__header { margin-bottom: 40px; padding-bottom: 32px; border-bottom: 1px solid var(--hairline); }
.rh-article__label {
    font-size: 11px; font-weight: 600; letter-spacing: 0.88px; text-transform: uppercase;
    color: var(--muted); margin-bottom: 12px;
}
.rh-article__title {
    font-size: 42px; font-weight: 400; line-height: 1.15; letter-spacing: -0.84px;
    color: var(--ink); margin-bottom: 16px;
}
.rh-article__meta { font-size: 13px; color: var(--muted); }
.rh-article__img {
    width: 100%; max-height: 440px; object-fit: cover;
    border-radius: var(--rounded-lg); border: 1px solid var(--hairline); margin-bottom: 40px;
}
.rh-article__body { font-size: 16px; color: var(--body); line-height: 1.7; }
.rh-article__body h2 {
    font-size: 26px; font-weight: 400; letter-spacing: -0.325px; color: var(--ink);
    margin: 40px 0 16px;
}
.rh-article__body h3 {
    font-size: 20px; font-weight: 600; color: var(--ink); margin: 28px 0 12px;
}
.rh-article__body p { margin-bottom: 16px; }
.rh-article__body ul, .rh-article__body ol {
    margin: 0 0 16px 24px; list-style: disc;
}
.rh-article__body ol { list-style: decimal; }
.rh-article__body li { margin-bottom: 6px; }
.rh-article__body a { color: var(--primary); text-decoration: underline; }
.rh-article__body a:hover { color: var(--primary-active); }
.rh-article__body .rh-note {
    background: var(--canvas-soft); border: 1px solid var(--hairline);
    border-left: 3px solid var(--primary); border-radius: var(--rounded-sm);
    padding: 16px 20px; margin: 24px 0; font-size: 15px; color: var(--ink);
}
.rh-article__body table {
    width: 100%; border-collapse: collapse; margin: 24px 0; font-size: 14px;
}
.rh-article__body th {
    text-align: left; font-weight: 600; color: var(--ink); background: var(--surface-strong);
    padding: 10px 14px; border: 1px solid var(--hairline);
}
.rh-article__body td {
    padding: 10px 14px; border: 1px solid var(--hairline); color: var(--body);
}

.rh-sidebar { position: sticky; top: 80px; align-self: start; }
.rh-sidebar__card {
    background: var(--surface-card); border: 1px solid var(--hairline);
    border-radius: var(--rounded-lg); padding: 24px; margin-bottom: 24px;
}
.rh-sidebar__title { font-size: 13px; font-weight: 600; color: var(--ink); letter-spacing: 0.4px; text-transform: uppercase; margin-bottom: 16px; }
.rh-sidebar__list li { margin-bottom: 10px; }
.rh-sidebar__list a { font-size: 14px; color: var(--body); }
.rh-sidebar__list a:hover { color: var(--primary); }
.rh-sidebar__toc li { counter-increment: toc-counter; }
.rh-sidebar__toc a { font-size: 13px; color: var(--muted); }
.rh-sidebar__toc a:hover { color: var(--ink); }

.rh-btn {
    display: inline-flex; align-items: center; justify-content: center;
    font-family: var(--font-sans); font-size: 14px; font-weight: 500;
    line-height: 1; cursor: pointer; border: none; border-radius: var(--rounded-md);
    padding: 10px 18px; height: 40px; transition: background 0.15s, color 0.15s;
}
.rh-btn--primary { background: var(--primary); color: var(--on-primary); }
.rh-btn--primary:hover { background: var(--primary-active); color: var(--on-primary); }
.rh-btn--secondary {
    background: var(--surface-card); color: var(--ink);
    border: 1px solid var(--hairline-strong);
}
.rh-btn--secondary:hover { background: var(--surface-strong); }
.rh-btn--lg { padding: 12px 24px; height: 48px; font-size: 15px; }

.rh-form { background: var(--surface-card); border: 1px solid var(--hairline); border-radius: var(--rounded-lg); padding: 40px; }
.rh-form__title { font-size: 26px; font-weight: 400; letter-spacing: -0.325px; color: var(--ink); margin-bottom: 8px; }
.rh-form__desc { font-size: 15px; color: var(--body); margin-bottom: 32px; }
.rh-form__group { margin-bottom: 20px; }
.rh-form__label { display: block; font-size: 14px; font-weight: 500; color: var(--ink); margin-bottom: 6px; }
.rh-form__input, .rh-form__textarea {
    width: 100%; background: var(--canvas); color: var(--ink); font-family: var(--font-sans); font-size: 16px;
    border: 1px solid var(--hairline-strong); border-radius: var(--rounded-md);
    padding: 12px 16px; outline: none; transition: border-color 0.15s;
}
.rh-form__input:focus, .rh-form__textarea:focus { border-color: var(--ink); }
.rh-form__textarea { resize: vertical; min-height: 120px; height: auto; }
.rh-form__note { font-size: 12px; color: var(--muted); margin-top: 6px; }
.rh-form__msg { display: none; padding: 14px 18px; border-radius: var(--rounded-md); font-size: 15px; margin-top: 16px; }
.rh-form__msg--success { background: #e8f5f1; color: var(--semantic-success); border: 1px solid #b8ddd4; }
.rh-form__spinner { display: none; width: 18px; height: 18px; border: 2px solid rgba(255,255,255,0.4); border-top-color: #fff; border-radius: 50%; animation: spin 0.6s linear infinite; margin-left: 8px; }
@keyframes spin { to { transform: rotate(360deg); } }

.rh-page-header { padding: 64px 0 48px; border-bottom: 1px solid var(--hairline); }
.rh-page-header__title { font-size: 42px; font-weight: 400; letter-spacing: -0.84px; color: var(--ink); margin-bottom: 12px; }
.rh-page-header__sub { font-size: 16px; color: var(--body); }

.rh-page-body { padding: 64px 0; font-size: 16px; color: var(--body); line-height: 1.7; }
.rh-page-body h2 { font-size: 26px; font-weight: 400; color: var(--ink); margin: 40px 0 16px; letter-spacing: -0.325px; }
.rh-page-body h3 { font-size: 20px; font-weight: 600; color: var(--ink); margin: 28px 0 10px; }
.rh-page-body p { margin-bottom: 16px; }
.rh-page-body ul { margin: 0 0 16px 24px; list-style: disc; }
.rh-page-body li { margin-bottom: 6px; }
.rh-page-body a { color: var(--primary); text-decoration: underline; }
.rh-page-body a:hover { color: var(--primary-active); }

.rh-footer {
    background: var(--canvas); border-top: 1px solid var(--hairline); padding: 64px 0 0;
}
.rh-footer__inner {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 48px; padding-bottom: 48px;
}
.rh-footer__brand { font-size: 16px; font-weight: 600; color: var(--ink); margin-bottom: 6px; }
.rh-footer__tagline { font-size: 13px; color: var(--muted); }
.rh-footer__heading { font-size: 11px; font-weight: 600; letter-spacing: 0.88px; text-transform: uppercase; color: var(--muted); margin-bottom: 14px; }
.rh-footer ul li { margin-bottom: 8px; }
.rh-footer ul a { font-size: 14px; color: var(--body); }
.rh-footer ul a:hover { color: var(--ink); }
.rh-footer p { font-size: 14px; color: var(--body); }
.rh-footer__bottom {
    border-top: 1px solid var(--hairline); padding: 24px 0;
}
.rh-footer__bottom .rh-container { display: flex; flex-direction: column; gap: 6px; }
.rh-footer__bottom p { font-size: 13px; color: var(--muted); }
.rh-footer__disclaimer { font-size: 12px; color: var(--muted-soft); }

.rh-cookie {
    display: none; position: fixed; bottom: 0; left: 0; right: 0; z-index: 999;
    background: var(--ink); color: var(--canvas); padding: 20px 24px;
}
.rh-cookie__inner {
    max-width: 1200px; margin: 0 auto;
    display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap;
}
.rh-cookie p { font-size: 14px; }
.rh-cookie a { color: var(--primary); text-decoration: underline; }
.rh-cookie__actions { display: flex; gap: 12px; flex-shrink: 0; }
.rh-cookie .rh-btn--secondary { background: transparent; color: var(--canvas); border-color: rgba(255,255,255,0.3); }
.rh-cookie .rh-btn--secondary:hover { background: rgba(255,255,255,0.1); }

.rh-breadcrumb { padding: 16px 0; font-size: 13px; color: var(--muted); }
.rh-breadcrumb a { color: var(--muted); }
.rh-breadcrumb a:hover { color: var(--ink); }
.rh-breadcrumb span { margin: 0 6px; }

.rh-related { padding: 64px 0; border-top: 1px solid var(--hairline); }
.rh-related__title { font-size: 22px; font-weight: 400; color: var(--ink); margin-bottom: 32px; letter-spacing: -0.11px; }

@media (max-width: 1024px) {
    .rh-hero__title { font-size: 42px; }
    .rh-article-grid { grid-template-columns: 1fr; }
    .rh-sidebar { position: static; }
    .rh-grid--3 { grid-template-columns: repeat(2, 1fr); }
    .rh-footer__inner { grid-template-columns: repeat(2, 1fr); gap: 32px; }
}
@media (max-width: 768px) {
    .rh-nav__menu { display: none; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: var(--canvas); border-bottom: 1px solid var(--hairline); padding: 16px 24px; gap: 16px; }
    .rh-nav__menu.is-open { display: flex; }
    .rh-nav__burger { display: flex; }
    .rh-nav { position: relative; }
    .rh-hero__title { font-size: 32px; letter-spacing: -0.8px; }
    .rh-section__title { font-size: 28px; }
    .rh-article__title { font-size: 30px; }
    .rh-grid--3, .rh-grid--2 { grid-template-columns: 1fr; }
    .rh-footer__inner { grid-template-columns: 1fr; gap: 24px; }
    .rh-form { padding: 24px; }
    .rh-page-header__title { font-size: 30px; }
}
@media (max-width: 640px) {
    .rh-hero { padding: 48px 0 40px; }
    .rh-section { padding: 48px 0; }
}