:root {
    --bg: #eef1f6;
    --bg-grad-a: #eef1f6;
    --bg-grad-b: #e4eaf6;
    --surface: #ffffff;
    --surface-alt: #f4f6fa;
    --border: #e1e5ec;
    --text: #161a22;
    --text-muted: #6b7280;
    --text-faint: #9aa1ad;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --accent-soft: #eaf0ff;
    --accent-text: #2354d6;
    --success: #16a34a;
    --danger: #e1493f;
    --danger-soft: #fdecea;
    --shadow: 0 20px 45px -10px rgba(30, 41, 80, 0.16);
    --shadow-sm: 0 4px 14px rgba(30, 41, 80, 0.08);
    --radius-lg: 22px;
    --radius-md: 13px;
    --radius-sm: 10px;
    --transition: 0.18s ease;
    --whatsapp-color: #25d366;
}

[data-theme="dark"] {
    --bg: #0d0f14;
    --bg-grad-a: #0d0f14;
    --bg-grad-b: #11162a;
    --surface: #161922;
    --surface-alt: #1c2029;
    --border: #272b36;
    --text: #f1f2f5;
    --text-muted: #9da1ac;
    --text-faint: #686c78;
    --accent: #4d7dff;
    --accent-hover: #6e93ff;
    --accent-soft: #1c2747;
    --accent-text: #8caaff;
    --success: #34d878;
    --danger: #f0635a;
    --danger-soft: #2c1e22;
    --shadow: 0 20px 45px -10px rgba(0, 0, 0, 0.55);
    --shadow-sm: 0 4px 14px rgba(0, 0, 0, 0.35);
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    padding: 0;
    height: 100%;
}

body {
    background: radial-gradient(circle at 20% 0%, var(--bg-grad-b) 0%, var(--bg-grad-a) 55%);
    color: var(--text);
    font-family: "Inter", "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
    transition: background var(--transition), color var(--transition);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

* {
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
}

/* ── Tema toggle ── */
.theme-toggle {
    position: fixed;
    top: 18px;
    right: 18px;
    z-index: 50;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-sm);
    transition: background var(--transition), border-color var(--transition), transform 0.15s ease;
}

.theme-toggle:hover {
    transform: translateY(-2px);
    border-color: var(--accent);
    color: var(--accent);
}

.theme-toggle svg {
    width: 19px;
    height: 19px;
}

.theme-toggle .icon-moon {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
    display: block;
}

/* ── Card ── */
.login-card {
    width: 100%;
    max-width: 380px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    padding: 36px 30px 30px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    position: relative;
    overflow: hidden;
    animation: cardIn 0.5s cubic-bezier(.22, 1, .36, 1);
}

.login-card::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), #60a5fa);
}

@keyframes cardIn {
    from {
        opacity: 0;
        transform: translateY(10px) scale(.98);
    }

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

.brand-banner {
    align-self: center;
    font-size: 14.5px;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: #fff;
    background: linear-gradient(135deg, var(--accent), #1d4ed8);
    padding: 7px 20px;
    border-radius: 999px;
    box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
    margin-bottom: 22px;
}

/* ── Pasos (uno visible a la vez) ── */
.reg-step {
    display: none;
    flex-direction: column;
    gap: 12px;
    animation: stepIn 0.25s ease;
}

.reg-step.is-active {
    display: flex;
}

@keyframes stepIn {
    from {
        opacity: 0;
        transform: translateY(6px);
    }

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

.reg-head {
    text-align: left;
    margin-bottom: 4px;
}

.reg-title {
    margin: 0 0 4px;
    font-size: 1.32rem;
    font-weight: 800;
    letter-spacing: -0.01em;
    color: var(--text);
}

.reg-sub {
    margin: 0;
    font-size: 13.5px;
    color: var(--text-muted);
}

.reg-back {
    align-self: flex-start;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--surface-alt);
    color: var(--text-muted);
    font-size: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background var(--transition), color var(--transition);
    margin-bottom: 6px;
}

.reg-back:hover {
    background: var(--accent-soft);
    color: var(--accent-text);
}

/* ── Botón Google ── */
.btn-google {
    width: 100%;
    padding: 13px 16px;
    border-radius: var(--radius-md);
    border: 1.5px solid var(--border);
    background: var(--surface);
    color: var(--text);
    font-size: 14.5px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: border-color var(--transition), background var(--transition),
        transform 0.12s ease, box-shadow var(--transition);
}

.btn-google:hover {
    border-color: var(--accent);
    background: var(--accent-soft);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.btn-google:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* ── Divisor "o" ── */
.reg-divider {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-faint);
    font-size: 12px;
    margin: 4px 0;
}

.reg-divider::before,
.reg-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: var(--border);
}

/* ── Inputs ── */
.field-label {
    font-size: 12px;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin: 4px 0 -4px;
}

.field-input {
    width: 100%;
    padding: 13px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-md);
    background: var(--surface-alt);
    color: var(--text);
    font-size: 15px;
    letter-spacing: 0.01em;
    outline: none;
    transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
}

.field-input:focus {
    border-color: var(--accent);
    background: var(--surface);
    box-shadow: 0 0 0 4px var(--accent-soft);
}

.pin-eye {
    position: absolute;
    right: 10px;
    cursor: pointer;
    opacity: 0.5;
    user-select: none;
}

/* ── Botón primario ── */
.btn-primary {
    width: 100%;
    padding: 14px 16px;
    border: none;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--accent), var(--accent-hover));
    color: #fff;
    font-size: 15px;
    font-weight: 700;
    letter-spacing: 0.01em;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    box-shadow: 0 10px 24px -6px rgba(37, 99, 235, 0.5);
    transition: filter var(--transition), transform 0.12s ease, box-shadow var(--transition);
}

.btn-primary:hover {
    filter: brightness(1.07);
    transform: translateY(-1px);
    box-shadow: 0 14px 28px -6px rgba(37, 99, 235, 0.6);
}

.btn-primary:active {
    transform: scale(0.98);
}

.btn-primary:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.btn-spinner {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    border: 2px solid rgba(255, 255, 255, 0.4);
    border-top-color: #fff;
    animation: spin 0.7s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ── Link volver a login ── */
.reg-link-back {
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
    text-decoration: none;
    margin-top: 8px;
    padding: 4px;
    transition: color var(--transition);
}

.reg-link-back:hover {
    color: var(--accent-text);
}

/* ── Error ── */
.reg-error {
    margin: 4px 0 0;
    font-size: 13.5px;
    color: var(--danger);
    background: var(--danger-soft);
    border-radius: var(--radius-sm);
    padding: 10px 12px;
}

/* ── Éxito ── */
.reg-success-icon {
    align-self: center;
    width: 58px;
    height: 58px;
    border-radius: 50%;
    background: var(--success);
    color: #fff;
    font-size: 28px;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 6px auto 4px;
    animation: popIn 0.4s cubic-bezier(.34, 1.56, .64, 1);
}

@keyframes popIn {
    from {
        transform: scale(0.5);
        opacity: 0;
    }

    to {
        transform: scale(1);
        opacity: 1;
    }
}

/* ── Snackbar ── */
.snackbar {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--danger);
    color: #fff;
    padding: 14px 28px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 14px;
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.4s ease, opacity 0.4s ease, visibility 0.4s ease;
    z-index: 999;
    max-width: 90%;
    text-align: center;
    pointer-events: none;
}

.snackbar.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
    visibility: visible;
}

@media (max-width: 480px) {
    body {
        padding: 16px;
    }

    .login-card {
        padding: 30px 22px 24px;
    }

    .theme-toggle {
        top: 12px;
        right: 12px;
        width: 38px;
        height: 38px;
    }

    .snackbar {
        bottom: 20px;
        padding: 12px 20px;
        font-size: 13px;
    }
}