:root {
    --kf-primary: #2563eb;
    --kf-bg: #f8fafc;
    --kf-card: #ffffff;
    --kf-text: #0f172a;
    --kf-muted: #64748b;
    --kf-border: #e2e8f0;
    --kf-danger: #dc2626;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    min-height: 100vh;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    color: var(--kf-text);
    background: radial-gradient(circle at top, rgba(37, 99, 235, 0.12), transparent 32rem), var(--kf-bg);
}

.kf-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 1.5rem;
}

.kf-card {
    width: 100%;
    max-width: 420px;
    padding: 2rem;
    border: 1px solid var(--kf-border);
    border-radius: 1.25rem;
    background: var(--kf-card);
    box-shadow: 0 24px 80px rgba(15, 23, 42, 0.12);
}

.kf-logo {
    display: flex;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.kf-logo img {
    max-width: 180px;
    max-height: 64px;
}

h1 {
    margin: 0 0 1.5rem;
    font-size: 1.5rem;
    text-align: center;
}

.kf-form {
    display: grid;
    gap: 1rem;
}

.kf-field {
    display: grid;
    gap: 0.4rem;
    font-size: 0.95rem;
}

.kf-field span { color: var(--kf-muted); }

.kf-field input {
    width: 100%;
    padding: 0.8rem 0.9rem;
    border: 1px solid var(--kf-border);
    border-radius: 0.75rem;
    font: inherit;
}

.kf-button {
    border: 0;
    border-radius: 0.75rem;
    padding: 0.85rem 1rem;
    background: var(--kf-primary);
    color: white;
    font: inherit;
    font-weight: 600;
    cursor: pointer;
}

.kf-alert {
    padding: 0.8rem 0.9rem;
    border-radius: 0.75rem;
    margin-bottom: 1rem;
}

.kf-alert-error {
    color: var(--kf-danger);
    background: rgba(220, 38, 38, 0.08);
}

@media (max-width: 480px) {
    .kf-page { align-items: stretch; padding: 0; }
    .kf-card {
        min-height: 100vh;
        max-width: none;
        border-radius: 0;
        border: 0;
        box-shadow: none;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }
}