*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

/* ── Skip link ── */
.skip-link {
    position: absolute;
    top: -100%;
    left: 0;
    background: var(--verde);
    color: #fff;
    padding: 0.5rem 1rem;
    z-index: 9999;
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 0 0 var(--radius, 8px) 0;
    transition: top 0.1s;
}
.skip-link:focus {
    top: 0;
}

/* ── Screen-reader only ── */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
    border: 0;
}

:root {
    --verde: #2e7d32;
    --verde-scuro: #1b5e20;
    --verde-chiaro: #e8f5e9;
    --arancio: #e65100;
    --grigio: #546e7a;
    --grigio-chiaro: #eceff1;
    --testo: #212121;
    --bianco: #ffffff;
    --errore: #c62828;
    --bordo: #cfd8dc;
    --radius: 8px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.12);
}

body {
    font-family: 'Segoe UI', system-ui, sans-serif;
    background-color: var(--verde-chiaro);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.login-card {
    background: var(--bianco);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 420px;
    padding: 2.5rem 2rem;
}

.login-card__header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-card__logo {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.login-card__title {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--verde-scuro);
    margin-bottom: 0.25rem;
}

.login-card__subtitle {
    font-size: 0.85rem;
    color: var(--grigio);
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--testo);
    margin-bottom: 0.4rem;
}

.form-group input {
    width: 100%;
    padding: 0.65rem 0.85rem;
    border: 1px solid #6b6b6b;
    border-radius: var(--radius);
    font-size: 0.95rem;
    color: var(--testo);
    transition: border-color 0.2s;
    outline: none;
}

.form-group input:focus {
    border-color: var(--verde);
    box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.25);
}

.form-check {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1.25rem;
}

.form-check input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    accent-color: var(--verde);
    cursor: pointer;
    flex-shrink: 0;
}

.form-check label {
    font-size: 0.85rem;
    color: var(--grigio);
    cursor: pointer;
    user-select: none;
}

.btn-login {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--verde);
    color: var(--bianco);
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
    margin-top: 0.5rem;
}

.btn-login:hover:not(:disabled) {
    background-color: var(--verde-scuro);
}

.btn-login:focus-visible {
    outline: 3px solid var(--verde-scuro);
    outline-offset: 2px;
}

.btn-login:disabled {
    opacity: 0.65;
    cursor: not-allowed;
}

.alert {
    padding: 0.75rem 1rem;
    border-radius: var(--radius);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    animation: alert-fadein 0.2s ease;
}

.alert:empty {
    display: none;
    margin: 0;
    padding: 0;
    border: none;
    animation: none;
}

@keyframes alert-fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

.alert--errore {
    background-color: #ffebee;
    color: var(--errore);
    border: 1px solid #ef9a9a;
}

.spinner {
    display: inline-block;
    width: 1em;
    height: 1em;
    border: 2px solid rgba(255,255,255,0.4);
    border-top-color: var(--bianco);
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    vertical-align: middle;
    margin-right: 0.4rem;
}

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

.login-card__footer {
    text-align: center;
    margin-top: 1.5rem;
    font-size: 0.8rem;
    color: var(--grigio);
}

.alert--successo {
    background-color: #e8f5e9;
    color: #2e7d32;
    border: 1px solid #a5d6a7;
}

.link-reset {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.85rem;
}

.link-reset a {
    color: var(--verde);
    text-decoration: none;
}

.link-reset a:hover {
    text-decoration: underline;
}

.link-reset a:focus-visible {
    outline: 3px solid var(--verde);
    outline-offset: 2px;
    border-radius: 2px;
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}