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

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

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

body {
    background: var(--canvas);
    color: var(--body);
    font-family: var(--font-sans);
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    min-height: 100vh;
}

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

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

.sf-nav {
    background: var(--canvas);
    border-bottom: 1px solid var(--hairline);
    position: sticky;
    top: 0;
    z-index: 100;
    height: 64px;
}

.sf-nav__inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    align-items: center;
    gap: 32px;
}

.sf-nav__logo {
    font-size: 18px;
    font-weight: 600;
    color: var(--ink);
    letter-spacing: -0.3px;
    flex-shrink: 0;
}

.sf-nav__menu {
    display: flex;
    align-items: center;
    gap: 4px;
    margin-left: auto;
}

.sf-nav__link {
    font-size: 14px;
    font-weight: 500;
    color: var(--body);
    padding: 8px 12px;
    border-radius: var(--r-sm);
    display: flex;
    align-items: center;
    gap: 4px;
    transition: color 0.15s, background 0.15s;
    white-space: nowrap;
}

.sf-nav__link:hover {
    color: var(--ink);
    background: var(--surface-strong);
}

.sf-nav__has-drop { position: relative; }

.sf-nav__drop {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    left: 0;
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-lg);
    padding: 8px;
    min-width: 260px;
    box-shadow: 0 4px 16px rgba(38,37,30,0.08);
}

.sf-nav__has-drop:hover .sf-nav__drop,
.sf-nav__has-drop.is-open .sf-nav__drop { display: block; }

.sf-nav__drop-link {
    display: block;
    font-size: 14px;
    color: var(--body);
    padding: 8px 12px;
    border-radius: var(--r-sm);
}

.sf-nav__drop-link:hover { background: var(--canvas); color: var(--ink); }

.sf-nav__burger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    margin-left: auto;
}

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

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

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

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

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

.sf-btn--secondary:hover { background: var(--canvas); }

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

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

.sf-hero {
    padding: 80px 24px;
    max-width: 1200px;
    margin: 0 auto;
}

.sf-hero__label {
    display: inline-flex;
    align-items: center;
    background: var(--surface-strong);
    color: var(--ink);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    padding: 4px 10px;
    border-radius: var(--r-pill);
    margin-bottom: 24px;
}

.sf-hero__title {
    font-size: 56px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -1.5px;
    color: var(--ink);
    max-width: 820px;
    margin-bottom: 20px;
}

.sf-hero__sub {
    font-size: 18px;
    color: var(--body);
    max-width: 560px;
    line-height: 1.5;
    margin-bottom: 40px;
}

.sf-hero__img {
    width: 100%;
    border-radius: var(--r-lg);
    border: 1px solid var(--hairline);
    overflow: hidden;
    margin-top: 48px;
    max-height: 480px;
    object-fit: cover;
}

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

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

.sf-section--alt { background: var(--canvas-soft); }

.sf-section__label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 16px;
}

.sf-section__title {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--ink);
    margin-bottom: 16px;
}

.sf-section__sub {
    font-size: 16px;
    color: var(--body);
    max-width: 620px;
    line-height: 1.5;
}

.sf-grid { display: grid; gap: 16px; }
.sf-grid--3 { grid-template-columns: repeat(3, 1fr); }
.sf-grid--2 { grid-template-columns: repeat(2, 1fr); }

.sf-card {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-lg);
    padding: 24px;
}

.sf-card__img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--r-md);
    margin-bottom: 16px;
}

.sf-card__label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 8px;
}

.sf-card__title {
    font-size: 18px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.3;
    margin-bottom: 12px;
}

.sf-card__body {
    font-size: 14px;
    color: var(--body);
    line-height: 1.5;
    margin-bottom: 16px;
}

.sf-card__link {
    font-size: 14px;
    font-weight: 500;
    color: var(--primary);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.sf-card__link:hover { color: var(--primary-active); }

.sf-article {
    max-width: 720px;
    margin: 0 auto;
    padding: var(--section) 24px;
}

.sf-article__header { margin-bottom: 40px; }

.sf-article__label {
    display: inline-flex;
    background: var(--surface-strong);
    color: var(--ink);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    padding: 4px 10px;
    border-radius: var(--r-pill);
    margin-bottom: 16px;
}

.sf-article__title {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--ink);
    margin-bottom: 16px;
}

.sf-article__meta {
    font-size: 13px;
    color: var(--muted);
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.sf-article__hero-img {
    width: 100%;
    border-radius: var(--r-lg);
    margin-bottom: 40px;
    max-height: 400px;
    object-fit: cover;
}

.sf-article__body h2 {
    font-size: 26px;
    font-weight: 400;
    letter-spacing: -0.325px;
    color: var(--ink);
    line-height: 1.25;
    margin: 40px 0 16px;
}

.sf-article__body h3 {
    font-size: 22px;
    font-weight: 400;
    letter-spacing: -0.11px;
    color: var(--ink);
    line-height: 1.3;
    margin: 32px 0 12px;
}

.sf-article__body p {
    color: var(--body);
    font-size: 16px;
    line-height: 1.7;
    margin-bottom: 20px;
}

.sf-article__body ul, .sf-article__body ol {
    margin: 0 0 20px 20px;
    color: var(--body);
    font-size: 16px;
    line-height: 1.7;
}

.sf-article__body ul li { list-style: disc; }
.sf-article__body ol li { list-style: decimal; }

.sf-article__body a { color: var(--primary); text-decoration: underline; }
.sf-article__body a:hover { color: var(--primary-active); }

.sf-article__body figure {
    margin: 32px 0;
}

.sf-article__body figure img {
    width: 100%;
    border-radius: var(--r-md);
    border: 1px solid var(--hairline);
}

.sf-article__body figcaption {
    font-size: 13px;
    color: var(--muted);
    margin-top: 8px;
    line-height: 1.4;
}

.sf-infobox {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-left: 3px solid var(--primary);
    border-radius: var(--r-md);
    padding: 20px 24px;
    margin: 28px 0;
}

.sf-infobox__title {
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.88px;
    color: var(--muted);
    margin-bottom: 8px;
}

.sf-infobox p { font-size: 15px; color: var(--body); margin: 0; }

.sf-related {
    border-top: 1px solid var(--hairline);
    padding-top: 40px;
    margin-top: 40px;
}

.sf-related__title {
    font-size: 22px;
    font-weight: 400;
    color: var(--ink);
    margin-bottom: 20px;
}

.sf-related__list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }

.sf-related__item {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-lg);
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.sf-related__item-label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
}

.sf-related__item-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.3;
}

.sf-related__item-link {
    font-size: 13px;
    color: var(--primary);
    margin-top: auto;
}

.sf-form {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--r-lg);
    padding: 40px;
}

.sf-form__title {
    font-size: 26px;
    font-weight: 400;
    letter-spacing: -0.325px;
    color: var(--ink);
    margin-bottom: 8px;
}

.sf-form__sub {
    font-size: 15px;
    color: var(--body);
    margin-bottom: 28px;
}

.sf-form__group { margin-bottom: 20px; }

.sf-form__label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--ink);
    margin-bottom: 6px;
}

.sf-form__input {
    width: 100%;
    background: var(--canvas);
    border: 1px solid var(--hairline-strong);
    border-radius: var(--r-md);
    padding: 12px 16px;
    height: 44px;
    font-family: var(--font-sans);
    font-size: 16px;
    color: var(--ink);
    transition: border-color 0.15s;
}

.sf-form__input:focus {
    outline: none;
    border-color: var(--primary);
}

.sf-form__input::placeholder { color: var(--muted-soft); }

.sf-form__input--error { border-color: var(--semantic-error); }

.sf-form__error {
    display: none;
    font-size: 13px;
    color: var(--semantic-error);
    margin-top: 4px;
}

.sf-form__error.is-visible { display: block; }

.sf-form__success {
    display: none;
    background: #e8f5f0;
    border: 1px solid #9fd4c0;
    border-radius: var(--r-md);
    padding: 16px 20px;
    font-size: 15px;
    color: var(--semantic-success);
    margin-top: 20px;
}

.sf-form__success.is-visible { display: block; }

.sf-form__loading {
    display: none;
    font-size: 14px;
    color: var(--muted);
    margin-top: 12px;
}

.sf-form__loading.is-visible { display: block; }

.sf-cookie {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--surface-card);
    border-top: 1px solid var(--hairline);
    z-index: 999;
    padding: 20px 24px;
}

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

.sf-cookie__inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 24px;
    flex-wrap: wrap;
}

.sf-cookie__text {
    flex: 1;
    font-size: 14px;
    color: var(--body);
    min-width: 240px;
}

.sf-cookie__text a { color: var(--primary); text-decoration: underline; }

.sf-cookie__actions { display: flex; gap: 8px; flex-shrink: 0; }

.sf-footer {
    background: var(--canvas);
    border-top: 1px solid var(--hairline);
    padding: 64px 24px 48px;
}

.sf-footer__inner {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 48px;
}

.sf-footer__logo {
    font-size: 18px;
    font-weight: 600;
    color: var(--ink);
    display: block;
    margin-bottom: 12px;
    letter-spacing: -0.3px;
}

.sf-footer__tagline {
    font-size: 14px;
    color: var(--muted);
    line-height: 1.5;
}

.sf-footer__col-title {
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.88px;
    color: var(--muted);
    margin-bottom: 16px;
}

.sf-footer__links li { margin-bottom: 8px; }

.sf-footer__links a {
    font-size: 14px;
    color: var(--body);
}

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

.sf-footer__contact p {
    font-size: 14px;
    color: var(--body);
    line-height: 1.6;
    margin-bottom: 8px;
}

.sf-footer__contact a { color: var(--primary); }

.sf-footer__bottom {
    max-width: 1200px;
    margin: 0 auto;
    border-top: 1px solid var(--hairline);
    padding-top: 24px;
    display: flex;
    justify-content: space-between;
    gap: 16px;
    flex-wrap: wrap;
}

.sf-footer__copy, .sf-footer__disclaimer {
    font-size: 13px;
    color: var(--muted);
}

.sf-page-header {
    padding: 64px 24px 40px;
    max-width: 1200px;
    margin: 0 auto;
    border-bottom: 1px solid var(--hairline);
    margin-bottom: 48px;
}

.sf-page-header__label {
    display: inline-flex;
    background: var(--surface-strong);
    color: var(--ink);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    padding: 4px 10px;
    border-radius: var(--r-pill);
    margin-bottom: 16px;
}

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

.sf-page-header__meta {
    font-size: 13px;
    color: var(--muted);
    margin-top: 12px;
}

.sf-prose {
    max-width: 720px;
    margin: 0 auto;
    padding: 0 24px 80px;
}

.sf-prose h2 {
    font-size: 26px;
    font-weight: 400;
    letter-spacing: -0.325px;
    color: var(--ink);
    margin: 40px 0 16px;
}

.sf-prose h3 {
    font-size: 20px;
    font-weight: 600;
    color: var(--ink);
    margin: 28px 0 12px;
}

.sf-prose p {
    font-size: 16px;
    color: var(--body);
    line-height: 1.7;
    margin-bottom: 20px;
}

.sf-prose ul {
    margin: 0 0 20px 20px;
    font-size: 16px;
    color: var(--body);
    line-height: 1.7;
}

.sf-prose ul li { list-style: disc; }
.sf-prose a { color: var(--primary); text-decoration: underline; }

.sf-updated {
    font-size: 13px;
    color: var(--muted);
    border-top: 1px solid var(--hairline);
    padding-top: 16px;
    margin-top: 48px;
}

@media (max-width: 1024px) {
    .sf-grid--3 { grid-template-columns: repeat(2, 1fr); }
    .sf-footer__inner { grid-template-columns: repeat(2, 1fr); }
    .sf-hero__title { font-size: 44px; }
}

@media (max-width: 768px) {
    .sf-nav__menu {
        display: none;
        flex-direction: column;
        align-items: flex-start;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--canvas);
        border-bottom: 1px solid var(--hairline);
        padding: 16px 24px 24px;
        gap: 4px;
    }
    .sf-nav__menu.is-open { display: flex; }
    .sf-nav__burger { display: flex; }
    .sf-nav__has-drop { width: 100%; }
    .sf-nav__drop { position: static; box-shadow: none; border: none; padding: 0 0 0 16px; display: none; }
    .sf-nav__has-drop.is-open .sf-nav__drop { display: block; }
    .sf-nav__link { width: 100%; }
    .sf-hero__title { font-size: 32px; }
    .sf-hero { padding: 48px 24px; }
    .sf-section__title { font-size: 28px; }
    .sf-grid--3, .sf-grid--2 { grid-template-columns: 1fr; }
    .sf-footer__inner { grid-template-columns: 1fr 1fr; }
    .sf-related__list { grid-template-columns: 1fr; }
    .sf-article__title { font-size: 28px; }
}

@media (max-width: 480px) {
    .sf-footer__inner { grid-template-columns: 1fr; }
    .sf-hero__title { font-size: 28px; }
    .sf-form { padding: 24px; }
}