/* ===== Theme ===== */
:root {
    --bg: #0b1020;
    --fg: #eaf0ff;
    --muted: #b9c3e6;
    --card: #121735;
    --accent: #6fa8ff;
    --accent2: #7ef0c2;
    --warn: #ffcc66;
    --danger: #ff7a7a;
    --shadow: 0 10px 30px rgba(0, 0, 0, .35)
}

* {
    box-sizing: border-box
}

html,
body {
    margin: 0;
    padding: 0;
    background: var(--bg);
    color: var(--fg);
    font: 16px/1.6 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji"
}

a {
    color: var(--accent)
}

a:hover {
    color: #a9caff
}

/* ===== Header & Nav ===== */
header {
    position: sticky;
    top: 0;
    z-index: 10;
    backdrop-filter: saturate(140%) blur(8px);
    background: rgba(11, 16, 32, .85);
    border-bottom: 1px solid rgba(255, 255, 255, .06)
}

.wrap {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 64px;
    flex-wrap: wrap
}

.brand img {
    padding-top: 5px;
    height: 85px;
    width: auto
}

@media (max-width:780px) {
    .brand img {
        height: 32px
    }
}

.navlinks {
    display: flex;
    flex-wrap: wrap;
    gap: 6px
}

.navlinks a {
    margin: 0 4px;
    text-decoration: none;
    font-weight: 600;
    color: var(--fg);
    padding: 8px 10px;
    border-radius: 8px
}

.menu-toggle {
    display: none;
    background: transparent;
    border: 1px solid rgba(255, 255, 255, .2);
    color: var(--fg);
    padding: 8px 10px;
    border-radius: 10px
}

@media (max-width:780px) {
    .menu-toggle {
        display: inline-flex;
        align-items: center;
        gap: 8px
    }

    .navlinks {
        display: none;
        width: 100%;
        flex-direction: column;
        padding: 10px 0
    }

    .nav.open .navlinks {
        display: flex
    }
}

/* ===== Sections & Cards ===== */
section {
    padding: 32px 0
}

h2 {
    font-size: clamp(22px, 3vw, 28px);
    margin: 0 0 16px
}

.grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 16px
}

.card {
    grid-column: span 12;
    background: var(--card);
    padding: 18px;
    border-radius: 14px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(255, 255, 255, .06)
}

.card2 {
    margin-top: 16px;
}

@media (min-width:720px) {
    .card.half {
        grid-column: span 6
    }
}

.card h3 {
    margin: 0 0 8px
}

.pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 10px;
    border-radius: 999px;
    font-size: 14px;
    background: rgba(255, 255, 255, .06);
    border: 1px solid rgba(255, 255, 255, .08)
}

.list {
    padding-left: 18px;
    margin: 10px 0
}

.kbd {
    display: inline-block;
    padding: .15em .45em;
    border: 1px solid rgba(255, 255, 255, .25);
    border-bottom-width: 2px;
    border-radius: 6px;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace
}

/* ===== Hero ===== */
.hero {
    padding: 70px 0 30px;
    background:
        radial-gradient(1200px 400px at 10% -10%, rgba(111, 168, 255, .15), transparent 60%),
        radial-gradient(900px 300px at 110% -20%, rgba(126, 240, 194, .12), transparent 60%)
}

.hero h1 {
    font-size: clamp(28px, 4vw, 42px);
    margin: 0 0 12px
}

.hero p {
    color: var(--muted);
    margin: 0;
    max-width: 70ch
}

.cta {
    display: flex;
    gap: 12px;
    margin-top: 18px;
    flex-wrap: wrap
}

.btn {
    background: var(--accent);
    color: #081028;
    border: none;
    padding: 12px 16px;
    border-radius: 10px;
    font-weight: 700;
    cursor: pointer;
    box-shadow: var(--shadow)
}

.btn.secondary {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, .15);
    color: var(--fg)
}

/* ===== Notices & Quiz ===== */
details {
    background: var(--card);
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, .06);
    padding: 12px 14px
}

details+details {
    margin-top: 10px
}

details summary {
    cursor: pointer;
    font-weight: 700
}

.notice {
    padding: 12px 14px;
    border-left: 4px solid var(--warn);
    background: rgba(255, 204, 102, .08);
    border-radius: 10px
}

.danger {
    border-left-color: var(--danger);
    background: rgba(255, 122, 122, .08)
}

.quiz {
    background: var(--card);
    padding: 18px;
    border-radius: 14px;
    border: 1px solid rgba(255, 255, 255, .06)
}

.quiz .q {
    margin: 16px 0
}

.quiz button {
    margin-top: 8px
}

.score {
    font-weight: 800
}

/* ===== Footer ===== */
footer {
    margin-top: 40px;
    padding: 24px 0 50px;
    color: var(--muted);
    border-top: 1px solid rgba(255, 255, 255, .08);
    text-align: center
}

.small {
    font-size: 14px;
    color: var(--muted)
}

@media (prefers-reduced-motion:reduce) {
    * {
        scroll-behavior: auto
    }
}