:root {
    --rss-navy: #0f1f3d;
    --rss-blue: #1d4ed8;
    --rss-soft: #eef4ff;
    --rss-border: #dbe4f0;
    --rss-text: #172033;
}

body {
    min-height: 100vh;
    margin: 0;
    background: radial-gradient(circle at top, #edf5ff 0, #f5f7fb 42%, #e8edf5 100%);
    color: var(--rss-text);
    font-family: Tahoma, Arial, sans-serif;
}

.installer-shell {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 32px 16px;
}

.installer-card {
    width: min(880px, 100%);
    overflow: hidden;
    border: 1px solid var(--rss-border);
    border-radius: 24px;
    background: #fff;
    box-shadow: 0 28px 70px rgba(15, 31, 61, .14);
}

.installer-header {
    padding: 34px 42px;
    color: #fff;
    background: linear-gradient(135deg, var(--rss-navy), #142f62 58%, var(--rss-blue));
}

.installer-header h1 {
    margin: 10px 0;
    font-size: 28px;
    font-weight: 800;
}

.installer-header p {
    margin: 0;
    opacity: .86;
}

.product-code {
    display: inline-flex;
    padding: 6px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,.14);
    font-size: 13px;
}

.stepper {
    display: flex;
    justify-content: center;
    gap: 14px;
    padding: 22px;
    background: var(--rss-soft);
    border-bottom: 1px solid var(--rss-border);
}

.step {
    width: 38px;
    height: 38px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    color: #64748b;
    background: #fff;
    border: 1px solid var(--rss-border);
    font-weight: 800;
}

.step.active {
    color: #fff;
    background: var(--rss-blue);
    border-color: var(--rss-blue);
}

.step.done {
    color: #fff;
    background: #16a34a;
    border-color: #16a34a;
}

.installer-body {
    padding: 38px 42px 42px;
}

.installer-body h2 {
    margin-bottom: 8px;
    font-size: 22px;
    font-weight: 800;
}

.btn-primary {
    background: var(--rss-blue);
    border-color: var(--rss-blue);
}

.form-control {
    min-height: 46px;
    border-color: var(--rss-border);
}