:root {
    --brand: #FF5A36;
    --brand-strong: #E0431F;
    --ink: #1B1F3B;
    --muted: #5A5F7D;
    --bg: #FFF8F2;
    --surface: #FFFFFF;
    --border: #F0E2D6;
    --ok-bg: #E8F6EE;
    --ok-ink: #1C6B3D;
    --err-bg: #FDECEA;
    --err-ink: #A3261A;
    color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
    :root {
        --brand: #FF7A5C;
        --brand-strong: #FF9478;
        --ink: #F2F2F8;
        --muted: #A9ABC3;
        --bg: #12131F;
        --surface: #1C1E2E;
        --border: #2C2F45;
        --ok-bg: #16352A;
        --ok-ink: #9BE3B8;
        --err-bg: #3D1C1A;
        --err-ink: #FFB4A8;
    }
}

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

html {
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
    font-size: 16px;
    line-height: 1.65;
}

.wrap {
    max-width: 760px;
    margin: 0 auto;
    padding: 0 16px;
}

.site-header {
    border-bottom: 1px solid var(--border);
    background: var(--surface);
}

.site-header .wrap {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 8px 16px;
    padding-top: 14px;
    padding-bottom: 14px;
}

.logo {
    font-weight: 700;
    font-size: 17px;
    color: var(--ink);
    text-decoration: none;
    letter-spacing: -0.01em;
}

.logo span {
    color: var(--brand);
}

.lang-switch {
    display: flex;
    gap: 6px;
    font-size: 14px;
}

.lang-switch a {
    display: inline-block;
    padding: 4px 10px;
    border: 1px solid var(--border);
    border-radius: 999px;
    color: var(--ink);
    text-decoration: none;
}

.lang-switch a:hover,
.lang-switch a:focus-visible {
    border-color: var(--brand);
    color: var(--brand);
}

main {
    padding-top: 24px;
    padding-bottom: 40px;
}

h1 {
    font-size: 30px;
    line-height: 1.25;
    margin: 8px 0 4px;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 21px;
    line-height: 1.3;
    margin: 32px 0 8px;
    padding-left: 10px;
    border-left: 4px solid var(--brand);
}

h3 {
    font-size: 17px;
    margin: 22px 0 6px;
}

p,
ul,
ol {
    margin: 0 0 12px;
}

ul,
ol {
    padding-left: 22px;
}

li {
    margin-bottom: 6px;
}

a {
    color: var(--brand);
    text-underline-offset: 2px;
}

a:hover {
    color: var(--brand-strong);
}

.meta {
    color: var(--muted);
    font-size: 14px;
    margin-bottom: 16px;
}

.lang-section {
    padding-top: 8px;
    scroll-margin-top: 12px;
}

.lang-section + .lang-section {
    margin-top: 40px;
    border-top: 2px solid var(--border);
    padding-top: 24px;
}

.lang-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--brand);
}

.toc {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 12px 16px;
    margin: 16px 0 8px;
    font-size: 15px;
}

.toc ol {
    margin: 0;
}

.note {
    background: var(--surface);
    border: 1px solid var(--border);
    border-left: 4px solid var(--brand);
    border-radius: 8px;
    padding: 12px 14px;
    margin: 16px 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 8px 0 16px;
    font-size: 15px;
}

th,
td {
    text-align: left;
    vertical-align: top;
    padding: 8px 10px;
    border: 1px solid var(--border);
}

th {
    background: var(--surface);
}

.table-scroll {
    overflow-x: auto;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 18px 16px;
    margin: 16px 0 8px;
}

.card h2 {
    margin-top: 0;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 6px;
}

input[type="email"] {
    width: 100%;
    font: inherit;
    color: var(--ink);
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 10px 12px;
}

input[type="email"]:focus {
    outline: 2px solid var(--brand);
    outline-offset: 1px;
}

button {
    font: inherit;
    font-weight: 600;
    margin-top: 12px;
    padding: 10px 18px;
    border: 0;
    border-radius: 10px;
    background: var(--brand);
    color: #FFFFFF;
    cursor: pointer;
}

button:hover {
    background: var(--brand-strong);
}

button:disabled {
    opacity: 0.6;
    cursor: default;
}

button.danger {
    background: #C62828;
}

button.danger:hover {
    background: #A51F1F;
}

.form-msg {
    margin-top: 12px;
    padding: 10px 12px;
    border-radius: 10px;
}

.form-msg.ok {
    background: var(--ok-bg);
    color: var(--ok-ink);
}

.form-msg.err {
    background: var(--err-bg);
    color: var(--err-ink);
}

.form-msg span {
    display: block;
}

[hidden] {
    display: none !important;
}

.site-footer {
    border-top: 1px solid var(--border);
    background: var(--surface);
    color: var(--muted);
    font-size: 14px;
}

.site-footer .wrap {
    padding-top: 18px;
    padding-bottom: 24px;
}

.site-footer nav {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 16px;
    margin-bottom: 8px;
}

.site-footer p {
    margin: 4px 0;
}

@media (max-width: 480px) {
    h1 {
        font-size: 25px;
    }

    h2 {
        font-size: 19px;
    }
}