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

body {
    font-family: 'Inter', sans-serif;
    background: #f5f5f7;
    color: #1d1d1f;
    min-height: 100vh;
}

/* ── Header ── */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(245, 245, 247, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    padding: 0 32px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 14px;
}

.header-left img {
    height: 28px;
}

.header-title {
    font-size: 13px;
    font-weight: 500;
    color: rgba(0, 0, 0, 0.45);
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.header-sep {
    width: 1px;
    height: 18px;
    background: rgba(0, 0, 0, 0.15);
}

.back-link {
    font-size: 13px;
    color: rgba(0, 0, 0, 0.45);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 5px;
    transition: color 0.15s;
}

.back-link:hover {
    color: rgba(0, 0, 0, 0.75);
}

/* ── Layout ── */
.layout {
    display: flex;
    max-width: 1100px;
    margin: 0 auto;
    padding: 40px 24px 80px;
    gap: 40px;
}

/* ── Sidebar ── */
.sidebar {
    width: 200px;
    flex-shrink: 0;
}

.sidebar-inner {
    position: sticky;
    top: 76px;
}

.sidebar-label {
    font-size: 10px;
    font-weight: 600;
    color: rgba(0, 0, 0, 0.35);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 10px;
    padding-left: 10px;
}

.nav-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.nav-list a {
    display: block;
    padding: 7px 10px;
    border-radius: 8px;
    font-size: 14px;
    color: rgba(0, 0, 0, 0.55);
    text-decoration: none;
    transition: background 0.15s, color 0.15s;
}

.nav-list a:hover,
.nav-list a.active {
    background: rgba(0, 0, 0, 0.06);
    color: rgba(0, 0, 0, 0.85);
}

/* ── Content ── */
.content {
    flex: 1;
    min-width: 0;
}

.section {
    margin-bottom: 64px;
    scroll-margin-top: 76px;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.section-number {
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.07);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    font-weight: 600;
    color: rgba(0, 0, 0, 0.45);
    flex-shrink: 0;
}

.section h2 {
    font-size: 20px;
    font-weight: 600;
    color: #1d1d1f;
}

.section p {
    font-size: 15px;
    line-height: 1.75;
    color: rgba(0, 0, 0, 0.65);
    margin-bottom: 16px;
}

.section p:last-child {
    margin-bottom: 0;
}

.section strong {
    color: rgba(0, 0, 0, 0.82);
}

/* ── Images ── */
.img-wrap {
    margin: 24px 0;
    text-align: center;
}

.img-wrap img {
    max-width: 100%;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12), 0 0 0 1px rgba(0, 0, 0, 0.05);
}

.img-wrap img.no-shadow {
    box-shadow: none;
    border-radius: 0;
}

img.flat {
    border-radius: 0 !important;
}

.img-row {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    margin: 24px 0;
    flex-wrap: wrap;
}

.img-row img {
    border-radius: 10px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1), 0 0 0 1px rgba(0, 0, 0, 0.05);
}

/* ── Button icons ── */
.btn-item {
    display: flex;
    align-items: flex-start;
    gap: 18px;
    margin-bottom: 28px;
}

.btn-item img {
    width: 52px;
    flex-shrink: 0;
    border-radius: 8px;
}

.btn-item-text {
    flex: 1;
}

.btn-item-text h3 {
    font-size: 15px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 4px;
}

.btn-item-text p {
    margin-bottom: 0;
}

/* ── Features list ── */
.features-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.features-list li {
    font-size: 15px;
    color: rgba(0, 0, 0, 0.65);
    line-height: 1.5;
    padding-left: 20px;
    position: relative;
}

.features-list li::before {
    content: '—';
    position: absolute;
    left: 0;
    color: rgba(0, 0, 0, 0.25);
}

/* ── Tables ── */
.table-wrap {
    margin: 20px 0;
    overflow-x: auto;
    border-radius: 10px;
    border: 1px solid rgba(0, 0, 0, 0.08);
}

table.guide-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

table.guide-table th,
table.guide-table td {
    text-align: left;
    padding: 10px 14px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.07);
    color: rgba(0, 0, 0, 0.65);
    line-height: 1.5;
    vertical-align: top;
}

table.guide-table thead th {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: rgba(0, 0, 0, 0.4);
    background: rgba(0, 0, 0, 0.03);
}

table.guide-table tbody tr:last-child td {
    border-bottom: none;
}

table.guide-table td:first-child {
    font-weight: 500;
    color: rgba(0, 0, 0, 0.8);
    white-space: nowrap;
}

table.guide-table strong {
    color: rgba(0, 0, 0, 0.82);
}

kbd {
    display: inline-block;
    font-family: 'Inter', sans-serif;
    font-size: 12px;
    font-weight: 600;
    color: rgba(0, 0, 0, 0.72);
    background: rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(0, 0, 0, 0.12);
    border-radius: 5px;
    padding: 1px 7px;
    line-height: 1.6;
    white-space: nowrap;
}

/* ── Callout ── */
.callout {
    background: rgba(0, 0, 0, 0.04);
    border-left: 3px solid rgba(0, 0, 0, 0.12);
    border-radius: 0 8px 8px 0;
    padding: 14px 18px;
    margin: 16px 0;
    font-size: 14px;
    color: rgba(0, 0, 0, 0.6);
    line-height: 1.65;
}

/* ── Footer ── */
.guide-footer {
    text-align: center;
    padding: 32px;
    font-size: 12px;
    color: rgba(0, 0, 0, 0.3);
    border-top: 1px solid rgba(0, 0, 0, 0.07);
}

.guide-footer a {
    color: inherit;
}

/* ── Mobile ── */
@media (max-width: 720px) {
    .sidebar {
        display: none;
    }

    .layout {
        padding: 24px 16px 60px;
    }

    .site-header {
        padding: 0 16px;
    }

    .img-wrap img {
        max-width: 100% !important;
    }
}