:root {
    --blue: #2563eb;
    --blue-dark: #1d4ed8;
    --blue-soft: #eaf1ff;
    --text: #0f172a;
    --muted: #64748b;
    --border: #dbe4f0;
    --surface: #ffffff;
    --background: #f6f8fc;
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    color: var(--text);
    background: var(--background);
}

button, input { font: inherit; }

.app-shell {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 250px 1fr;
}

.sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    padding: 24px 18px;
    background: var(--surface);
    border-right: 1px solid var(--border);
}

.brand {
    display: flex;
    gap: 12px;
    align-items: center;
    padding: 0 4px 24px;
    border-bottom: 1px solid var(--border);
}

.brand-mark {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    color: #fff;
    background: var(--blue);
    font-weight: 800;
}

.brand strong, .brand span { display: block; }
.brand strong { font-size: 1.1rem; }
.brand span {
    margin-top: 2px;
    color: var(--muted);
    font-size: .72rem;
    text-transform: uppercase;
    letter-spacing: .06em;
}

nav {
    display: grid;
    gap: 7px;
    margin-top: 24px;
}

.nav-item {
    padding: 12px 14px;
    border-radius: 10px;
    color: #475569;
    text-decoration: none;
    font-weight: 600;
}

.nav-item:hover, .nav-item.active {
    color: var(--blue-dark);
    background: var(--blue-soft);
}

.sidebar-footer {
    margin-top: auto;
    padding: 18px 8px 0;
    color: var(--muted);
    font-size: .8rem;
}

.content { padding: 44px 5vw 60px; }

.hero {
    width: min(860px, 100%);
    margin: 0 auto;
    text-align: center;
}

.badge {
    display: inline-flex;
    padding: 7px 13px;
    border-radius: 999px;
    color: var(--blue-dark);
    background: var(--blue-soft);
    font-size: .82rem;
    font-weight: 700;
}

h1 {
    margin: 18px 0 8px;
    font-size: clamp(2rem, 4vw, 3.25rem);
    letter-spacing: -.04em;
}

.hero > p {
    margin: 0;
    color: var(--muted);
    font-size: 1.05rem;
}

.search-tabs {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin: 30px 0 12px;
}

.tab {
    border: 0;
    padding: 10px 16px;
    border-radius: 999px;
    color: var(--muted);
    background: transparent;
    font-weight: 700;
}

.tab.active {
    color: #fff;
    background: var(--blue);
    box-shadow: 0 8px 20px rgba(37, 99, 235, .24);
}

.tab:disabled { opacity: .55; }

.search-box {
    display: flex;
    gap: 10px;
    padding: 8px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.search-box input {
    width: 100%;
    min-width: 0;
    border: 0;
    outline: 0;
    padding: 12px 14px;
    background: transparent;
}

.search-box button {
    border: 0;
    padding: 12px 22px;
    border-radius: 10px;
    color: #fff;
    background: var(--blue);
    font-weight: 800;
    cursor: pointer;
}

.search-box button:hover { background: var(--blue-dark); }

.status {
    min-height: 24px;
    margin-top: 13px !important;
    font-size: .84rem !important;
}

.feature-grid {
    width: min(1000px, 100%);
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 55px auto 0;
}

.feature-card {
    padding: 28px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: 0 8px 22px rgba(15, 23, 42, .04);
    text-align: center;
}

.icon {
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    margin: 0 auto 16px;
    border-radius: 12px;
    color: var(--blue-dark);
    background: var(--blue-soft);
    font-size: 1.25rem;
    font-weight: 900;
}

.feature-card h2 {
    margin: 0 0 9px;
    font-size: 1rem;
}

.feature-card p {
    margin: 0;
    color: var(--muted);
    font-size: .9rem;
    line-height: 1.65;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

@media (max-width: 820px) {
    .app-shell { grid-template-columns: 1fr; }
    .sidebar {
        position: static;
        height: auto;
        padding: 14px;
    }
    nav {
        display: flex;
        overflow-x: auto;
        margin-top: 14px;
    }
    .nav-item { white-space: nowrap; }
    .sidebar-footer { display: none; }
    .content { padding: 30px 18px 45px; }
    .feature-grid { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
    .search-box { flex-direction: column; }
    .search-box button { width: 100%; }
    .search-tabs { flex-wrap: wrap; }
}