/* ── Base ─────────────────────────────────────────── */
:root {
    --blue-50: #eff6ff;
    --blue-100: #dbeafe;
    --blue-200: #bfdbfe;
    --blue-400: #60a5fa;
    --blue-500: #3b82f6;
    --blue-600: #2563eb;
    --blue-700: #1d4ed8;
    --blue-800: #1e40af;
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-700: #374151;
    --gray-900: #111827;
    --radius: .75rem;
    --shadow: 0 4px 24px rgba(0, 0, 0, .06);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, .08);
    --transition: all .25s ease;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--gray-50);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
    margin: 0;
    height: auto;
}

/* ── Card wrapper ────────────────────────────────── */
.auth-card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    max-width: 460px;
    width: 100%;
    overflow: hidden;
    border: 1px solid var(--gray-200);
}

/* ── Header / logo area ──────────────────────────── */
.auth-header {
    background: linear-gradient(135deg, var(--blue-600), var(--blue-800));
    padding: 1rem 2rem 2.5rem;
    text-align: center;
    position: relative;
}

.auth-header::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 24px;
    background: var(--white);
    border-radius: 1.5rem 1.5rem 0 0;
}

/* ── Logo above header ────────────────────────── */
.auth-logo {
    text-align: center;
    padding: 1.5rem 2rem 1rem;
    background: var(--white);
}

.auth-logo img {
    max-width: 100%;
    height: auto;
}

.auth-header h4 {
    color: var(--white);
    font-weight: 700;
    font-size: 1.25rem;
    margin: 0;
    letter-spacing: -.25px;
}

.auth-header p {
    color: var(--blue-200);
    font-size: .85rem;
    margin: .25rem 0 0;
}

/* ── Tab nav ─────────────────────────────────────── */
.auth-body {
    padding: .5rem 2rem 2rem;
}

.auth-tabs {
    display: flex;
    border-bottom: 2px solid var(--gray-200);
    margin-bottom: 1.5rem;
}

.auth-tabs .tab-btn {
    flex: 1;
    text-align: center;
    padding: .75rem 0;
    font-weight: 600;
    font-size: .9rem;
    color: var(--gray-500);
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    cursor: pointer;
    transition: var(--transition);
    outline: none;
}

.auth-tabs .tab-btn:hover {
    color: var(--blue-600);
}

.auth-tabs .tab-btn.active {
    color: var(--blue-600);
    border-bottom-color: var(--blue-600);
}

/* ── Form panels ─────────────────────────────────── */
.tab-panel {
    display: none;
}

.tab-panel.active {
    display: block;
    animation: fadeUp .3s ease;
}

@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(8px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ── Form styling ────────────────────────────────── */
.form-group label {
    font-weight: 500;
    font-size: .85rem;
    color: var(--gray-700);
    margin-bottom: .35rem;
}

.form-control {
    border: 1px solid var(--gray-300);
    border-radius: .5rem;
    padding: .6rem .85rem;
    font-size: .9rem;
    transition: var(--transition);
    background: var(--white);
}

.form-control:focus {
    border-color: var(--blue-500);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, .15);
}

.form-control.is-invalid {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, .1);
}

.invalid-feedback {
    font-size: .8rem;
}

/* ── Buttons ─────────────────────────────────────── */
.btn-auth {
    background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
    color: var(--white);
    border: none;
    border-radius: .5rem;
    padding: .65rem 1rem;
    font-weight: 600;
    font-size: .95rem;
    width: 100%;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 2px 8px rgba(37, 99, 235, .25);
}

.btn-auth:hover {
    background: linear-gradient(135deg, var(--blue-600), var(--blue-800));
    box-shadow: 0 4px 14px rgba(37, 99, 235, .35);
    transform: translateY(-1px);
    color: var(--white);
}

.btn-auth:active {
    transform: translateY(0);
}

/* ── Input groups with icons ─────────────────────── */
.input-icon-wrap {
    position: relative;
}

.input-icon-wrap .bi {
    position: absolute;
    left: .85rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-500);
    font-size: 1rem;
    pointer-events: none;
    transition: var(--transition);
}

.input-icon-wrap .form-control {
    padding-left: 2.5rem;
}

.input-icon-wrap .form-control:focus~.bi,
.input-icon-wrap .form-control:not(:placeholder-shown)~.bi {
    color: var(--blue-500);
}

/* ── Divider ─────────────────────────────────────── */
.divider {
    display: flex;
    align-items: center;
    margin: 1.25rem 0;
    color: var(--gray-500);
    font-size: .8rem;
}

.divider::before,
.divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--gray-200);
}

.divider span {
    padding: 0 .75rem;
}

/* ── Switch link ─────────────────────────────────── */
.switch-text {
    text-align: center;
    font-size: .85rem;
    color: var(--gray-500);
    margin-top: 1rem;
}

.switch-text a {
    color: var(--blue-600);
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
}

.switch-text a:hover {
    color: var(--blue-700);
    text-decoration: underline;
}

/* ── Alert (success / error) ─────────────────────── */
.auth-alert {
    display: none;
    border-radius: .5rem;
    padding: .6rem 1rem;
    font-size: .85rem;
    font-weight: 500;
    margin-bottom: 1rem;
    animation: fadeUp .3s ease;
}

.auth-alert.success {
    display: block;
    background: #ecfdf5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.auth-alert.error {
    display: block;
    background: #fef2f2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

/* ── Footer ──────────────────────────────────────── */
.auth-footer {
    text-align: center;
    padding: 1rem 2rem 1.25rem;
    border-top: 1px solid var(--gray-100);
    font-size: .78rem;
    color: var(--gray-500);
}