:root {
    --blue-950: #0f172a;
    --blue-900: #172554;
    --blue-800: #1e3a8a;
    --indigo-600: #4f46e5;
    --emerald-500: #10b981;
    --slate-600: #475569;
    --slate-100: #f1f5f9;
    --line: #dbe3ef;
    --paper: #ffffff;
    --radius: 8px;
    --shadow: 0 20px 60px rgba(15, 23, 42, 0.16);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: "Inter", system-ui, sans-serif;
    color: var(--blue-950);
    background: linear-gradient(135deg, #eef2ff, #ecfeff 48%, #f8fafc);
}

h1,
h2,
.auth-brand {
    font-family: "Manrope", "Inter", sans-serif;
    letter-spacing: 0;
}

a {
    color: var(--indigo-600);
    text-decoration: none;
    font-weight: 700;
}

a:hover {
    color: var(--blue-900);
    text-decoration: underline;
}

a:focus-visible,
button:focus-visible,
.form-control:focus-visible {
    outline: 3px solid var(--emerald-500);
    outline-offset: 2px;
}

.auth-shell {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.2rem;
}

.auth-shell.spacious {
    align-items: flex-start;
    padding: 2rem 1.2rem;
}

.auth-card,
.register-card {
    width: min(1080px, 100%);
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--paper);
    box-shadow: var(--shadow);
}

.register-card {
    grid-template-columns: 0.8fr 1.2fr;
}

.auth-side {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    min-height: 620px;
    padding: 2.2rem;
    color: #fff;
    background:
        linear-gradient(160deg, rgba(15, 23, 42, 0.96), rgba(30, 58, 138, 0.94)),
        url("../assets/img/hero-learning-analytics.png");
    background-size: cover;
    background-position: center;
}

.auth-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    color: #fff;
    font-weight: 800;
}

.auth-brand.dark {
    color: var(--blue-900);
}

.auth-brand span {
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius);
    color: #fff;
    background: linear-gradient(135deg, var(--indigo-600), var(--emerald-500));
}

.auth-side h1,
.register-intro h1 {
    margin: 0.8rem 0;
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    line-height: 1.02;
}

.auth-side p {
    color: rgba(255, 255, 255, 0.78);
}

.auth-footnote {
    color: rgba(255, 255, 255, 0.74);
    border-top: 1px solid rgba(255, 255, 255, 0.18);
    padding-top: 1rem;
}

.section-label {
    margin: 0;
    color: var(--emerald-500);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.auth-form-panel,
.register-form-panel,
.register-intro {
    padding: clamp(1.35rem, 4vw, 2.4rem);
}

.auth-form-panel h2 {
    margin: 0.3rem 0;
    font-size: 1.8rem;
    font-weight: 800;
}

.form-copy,
.switch-link,
.register-intro p {
    color: var(--slate-600);
}

.form-control {
    border-color: var(--line);
    border-radius: var(--radius);
    padding: 0.75rem 0.85rem;
}

.form-control:focus {
    border-color: var(--indigo-600);
    box-shadow: 0 0 0 0.2rem rgba(79, 70, 229, 0.14);
}

.btn-edupredict {
    --bs-btn-color: #fff;
    --bs-btn-bg: var(--blue-900);
    --bs-btn-border-color: var(--blue-900);
    --bs-btn-hover-color: #fff;
    --bs-btn-hover-bg: var(--indigo-600);
    --bs-btn-hover-border-color: var(--indigo-600);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.45rem;
    border-radius: var(--radius);
    padding: 0.82rem 1rem;
    font-weight: 800;
}

.switch-link {
    margin: 1.3rem 0 0;
    text-align: center;
}

.register-intro {
    background: #f8fafc;
    border-right: 1px solid var(--line);
}

.alert {
    border-radius: var(--radius);
}

@media (max-width: 991.98px) {
    .auth-card,
    .register-card {
        grid-template-columns: 1fr;
    }

    .auth-side {
        min-height: 420px;
    }

    .register-intro {
        border-right: 0;
        border-bottom: 1px solid var(--line);
    }
}

@media (max-width: 575.98px) {
    .auth-shell {
        padding: 0;
    }

    .auth-card,
    .register-card {
        min-height: 100vh;
        border-radius: 0;
    }
}