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

:root {
    --navy-zrv: #1c2b3a;
    --steel-zrv: #476b8c;
    --sky-zrv: #2f7fe0;
    --ink-zrv: #16222e;
    --fog-zrv: #f1f4f8;
    --card-zrv: #ffffff;
    --slate-zrv: #4d6478;
    --edge-zrv: #d8e0ea;
    --body-zrv: "Tahoma", "Segoe UI", Geneva, sans-serif;
    --head-zrv: "Georgia", "Times New Roman", serif;
    --arc-zrv: 8px;
    --arc-lg-zrv: 14px;
    --cast1-zrv: 0 6px 16px rgba(22, 34, 46, .07);
    --cast2-zrv: 0 14px 32px rgba(22, 34, 46, .12);
}

html { scroll-behavior: smooth; }

body {
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    font-family: var(--body-zrv);
    background:
        linear-gradient(180deg, rgba(71, 107, 140, .1) 0%, rgba(241, 244, 248, 0) 46%),
        var(--fog-zrv);
    color: var(--ink-zrv);
    line-height: 1.72;
    font-size: 16px;
}

a {
    color: var(--steel-zrv);
    text-decoration: underline;
    text-underline-offset: 3px;
    transition: color .2s ease;
}
a:hover { color: var(--sky-zrv); }

/* ---------- top bar ---------- */
.bar-zrv {
    padding: 22px 20px 20px;
    background: rgba(28, 43, 58, .97);
    backdrop-filter: blur(10px);
    border-bottom: 3px solid var(--sky-zrv);
}
.bar-inner-zrv {
    max-width: 1100px;
    margin: 0 auto;
    text-align: center;
}
.bar-brand-zrv {
    display: inline-block;
    font-family: var(--head-zrv);
    font-size: 22px;
    font-weight: 700;
    letter-spacing: .22em;
    text-indent: .22em;
    color: #ffffff;
    text-decoration: none;
}
.bar-brand-zrv:hover { color: var(--sky-zrv); }

/* ---------- doc header ---------- */
.head-zrv {
    max-width: 860px;
    margin: 0 auto;
    padding: 52px 22px 24px;
    text-align: center;
}
.head-h1-zrv {
    font-family: var(--head-zrv);
    font-size: clamp(27px, 4.4vw, 42px);
    font-weight: 700;
    line-height: 1.24;
    color: var(--navy-zrv);
}
.head-sub-zrv {
    display: block;
    margin: 14px auto 0;
    max-width: 620px;
    font-size: 16px;
    color: var(--slate-zrv);
}
.head-stamp-zrv {
    display: inline-block;
    margin-top: 20px;
    padding: 7px 16px;
    border-radius: 999px;
    background: rgba(47, 127, 224, .12);
    border: 1px solid rgba(47, 127, 224, .45);
    font-size: 13px;
    font-weight: 700;
    color: var(--ink-zrv);
}

/* ---------- cards with corner badge ---------- */
.body-zrv {
    max-width: 820px;
    width: 100%;
    margin: 0 auto;
    padding: 18px 22px 70px;
    display: grid;
    gap: 18px;
}
.card-zrv {
    position: relative;
    background: var(--card-zrv);
    border: 1px solid var(--edge-zrv);
    border-radius: var(--arc-lg-zrv);
    box-shadow: var(--cast1-zrv);
    padding: 24px 26px;
}
.card-badge-zrv {
    position: absolute;
    top: -12px;
    right: 20px;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-family: var(--head-zrv);
    font-size: 16px;
    font-weight: 700;
    color: #ffffff;
    background: var(--sky-zrv);
    border: 3px solid var(--fog-zrv);
    box-shadow: 0 4px 10px rgba(47, 127, 224, .35);
}
.card-title-zrv {
    font-family: var(--head-zrv);
    font-size: clamp(19px, 2.4vw, 23px);
    font-weight: 700;
    line-height: 1.3;
    color: var(--navy-zrv);
    margin-bottom: 10px;
    padding-right: 44px;
}
.card-body-zrv p { margin-bottom: 12px; color: var(--slate-zrv); }
.card-body-zrv p:last-child { margin-bottom: 0; }
.card-body-zrv strong { color: var(--ink-zrv); }
.card-body-zrv ul,
.card-body-zrv ol {
    margin: 0 0 12px;
    padding-left: 0;
    list-style: none;
    color: var(--slate-zrv);
}
.card-body-zrv ol { counter-reset: zrvOrd; }
.card-body-zrv li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 8px;
}
.card-body-zrv ul > li::before {
    content: "";
    position: absolute;
    left: 3px;
    top: .58em;
    width: 8px;
    height: 8px;
    background: var(--sky-zrv);
    transform: rotate(45deg);
}
.card-body-zrv ol > li {
    counter-increment: zrvOrd;
    padding-left: 30px;
}
.card-body-zrv ol > li::before {
    content: counter(zrvOrd);
    position: absolute;
    left: 0;
    top: -.05em;
    width: 21px;
    height: 21px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-size: 11px;
    font-weight: 700;
    color: #fff;
    background: var(--steel-zrv);
}

/* ---------- accents ---------- */
.note-zrv {
    margin: 14px 0 4px;
    padding: 16px 18px;
    border-left: 4px solid var(--sky-zrv);
    border-radius: 0 var(--arc-zrv) var(--arc-zrv) 0;
    background: rgba(47, 127, 224, .09);
}
.note-zrv p { color: var(--ink-zrv); margin: 0; font-size: 15px; }

.pairs-zrv {
    margin: 12px 0;
    display: grid;
    gap: 10px;
}
.pair-zrv {
    display: grid;
    grid-template-columns: minmax(140px, 34%) 1fr;
    gap: 4px 16px;
    padding: 12px 14px;
    background: var(--fog-zrv);
    border: 1px solid var(--edge-zrv);
    border-radius: var(--arc-zrv);
    font-size: 15px;
}
.pair-k-zrv { font-weight: 700; color: var(--navy-zrv); }
.pair-v-zrv { color: var(--slate-zrv); }
@media (max-width: 560px) {
    .pair-zrv { grid-template-columns: 1fr; }
}

.grid-zrv {
    width: 100%;
    border-collapse: collapse;
    margin: 14px 0;
    font-size: 15px;
    background: var(--card-zrv);
    border: 1px solid var(--edge-zrv);
    border-radius: var(--arc-zrv);
    overflow: hidden;
}
.grid-zrv th {
    background: var(--navy-zrv);
    color: #ffffff;
    text-align: left;
    padding: 12px 14px;
    font-size: 14px;
    font-weight: 700;
}
.grid-zrv td {
    padding: 11px 14px;
    border-top: 1px solid var(--edge-zrv);
    color: var(--slate-zrv);
}
.grid-zrv tr:nth-child(even) td { background: rgba(71, 107, 140, .05); }

.tags-zrv {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 12px 0;
}
.tag-zrv {
    display: inline-block;
    padding: 5px 12px;
    border-radius: 999px;
    border: 1px solid var(--edge-zrv);
    background: var(--fog-zrv);
    font-size: 13px;
    font-weight: 700;
    color: var(--navy-zrv);
}

.close-zrv {
    max-width: 820px;
    margin: 0 auto;
    padding: 0 22px 60px;
}
.close-inner-zrv {
    padding: 20px 22px;
    border: 1px dashed rgba(71, 107, 140, .45);
    border-radius: var(--arc-lg-zrv);
    background: rgba(255, 255, 255, .7);
    font-size: 15px;
    color: var(--slate-zrv);
    text-align: center;
}

@media (max-width: 620px) {
    .card-zrv { padding: 22px 18px; }
    .head-zrv { padding-top: 40px; }
}

/* ---------- footer ---------- */
.end-zrv {
    margin-top: auto;
    flex-shrink: 0;
    background: var(--navy-zrv);
    color: #c1cddb;
    padding: 26px 20px 24px;
    text-align: center;
    border-top: 3px solid var(--sky-zrv);
}
.end-inner-zrv {
    max-width: 900px;
    margin: 0 auto;
}
.end-nav-zrv {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px 22px;
    margin-bottom: 14px;
}
.end-nav-zrv a {
    color: #c1cddb;
    font-size: 12px;
    text-decoration: none;
    border-bottom: 1px solid rgba(47, 127, 224, .5);
    padding-bottom: 2px;
}
.end-nav-zrv a:hover { color: var(--sky-zrv); }
.end-line-zrv {
    font-size: 12px;
    color: #c1cddb;
    margin-bottom: 10px;
}
.end-legal-zrv {
    font-size: 11px;
    line-height: 1.7;
    color: #99aabb;
    max-width: 760px;
    margin: 0 auto;
}