:root {
    --navy-950: #081722;
    --navy-900: #0d2438;
    --navy-800: #153752;
    --teal-500: #1fc7a6;
    --teal-600: #10a98a;
    --ink: #172b3a;
    --muted: #6d7c88;
    --line: #dfe7ec;
}

* {
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    margin: 0;
    color: var(--ink);
    background:
        radial-gradient(circle at 15% 18%, rgba(31, 199, 166, 0.16), transparent 30%),
        radial-gradient(circle at 85% 80%, rgba(66, 138, 202, 0.2), transparent 34%),
        linear-gradient(145deg, var(--navy-950), var(--navy-800));
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.auth-shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 32px 18px;
}

.auth-card {
    width: min(100%, 460px);
    padding: 40px;
    border: 1px solid rgba(255, 255, 255, 0.55);
    border-radius: 24px;
    background: rgba(255, 255, 255, 0.97);
    box-shadow: 0 28px 75px rgba(4, 20, 32, 0.32);
}

.brand-mark {
    width: 54px;
    height: 54px;
    display: grid;
    place-items: center;
    margin-bottom: 26px;
    border-radius: 17px;
    color: var(--navy-950);
    background: var(--teal-500);
    font-size: 1.6rem;
    font-weight: 900;
    box-shadow: 0 10px 24px rgba(31, 199, 166, 0.32);
}

.eyebrow {
    margin: 0 0 8px;
    color: var(--teal-600);
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 0.12em;
}

h1 {
    margin: 0;
    color: var(--navy-900);
    font-size: clamp(1.75rem, 5vw, 2.25rem);
    font-weight: 800;
    letter-spacing: -0.04em;
}

.subtitle {
    margin: 10px 0 28px;
    color: var(--muted);
    line-height: 1.55;
}

.form-label {
    color: var(--ink);
    font-size: 0.86rem;
    font-weight: 700;
}

.form-control {
    min-height: 48px;
    border: 1px solid var(--line);
    border-radius: 11px;
    color: var(--ink);
}

.form-control:focus {
    border-color: var(--teal-500);
    box-shadow: 0 0 0 4px rgba(31, 199, 166, 0.13);
}

.btn-primary {
    min-height: 50px;
    border: 0;
    border-radius: 11px;
    color: white;
    background: var(--navy-900);
    font-weight: 750;
}

.btn-primary:hover,
.btn-primary:focus {
    background: var(--navy-800);
    box-shadow: 0 8px 24px rgba(13, 36, 56, 0.22);
}

.alert {
    border: 0;
    border-radius: 12px;
    font-size: 0.9rem;
}

@media (max-width: 520px) {
    .auth-card {
        padding: 30px 24px;
        border-radius: 20px;
    }
}