.hidden {
    display: none !important;
}

.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;
}

.error-message {
    background: rgba(239, 68, 68, 0.08);
    color: #991b1b;
    padding: 1rem 1.25rem;
    border-radius: 0.75rem;
    margin-bottom: 1.5rem;
    border-left: 3px solid var(--danger-color);
    font-size: 0.875rem;
    line-height: 1.6;
}

.field-error {
    display: block;
    font-size: 0.875rem;
    color: var(--danger-color, #991b1b);
    margin-top: 0.25rem;
}

.success-message {
    background: var(--success-color);
    color: white;
}

.loading {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--text-secondary);
    font-size: 1rem;
}

.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    background: var(--bg-color);
    border-radius: 1.25rem;
    box-shadow: var(--shadow-sm);
    border: 2px dashed var(--border-color);
    transition: all 0.2s ease;
}

.empty-state:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

.empty-state p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: 0.5rem;
}

.empty-state a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.2s ease;
}

.empty-state a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

.status-badge {
    display: inline-block;
    padding: 0.375rem 0.875rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: all 0.2s ease;
}

.status-draft {
    background: #fef3c7;
    color: #92400e;
}

.status-submitted {
    background: #dbeafe;
    color: #1e40af;
}

.status-approved {
    background: #d1fae5;
    color: #065f46;
}

.status-rejected {
    background: #fee2e2;
    color: #991b1b;
}

.status-changes_requested {
    background: #fed7aa;
    color: #9a3412;
}

.status-withdrawn {
    background: #f1f5f9;
    color: #475569;
}

.role-badge {
    display: inline-block;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: capitalize;
}

.role-student {
    background-color: #dbeafe;
    color: #1e40af;
}

.role-instructor {
    background: #f5e6c7;
    color: #8a6a3a;
}

.role-admin {
    background: #b8e6e6;
    color: #2a6a6a;
}

.toast {
    position: fixed;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%) translateY(100%);
    padding: 0.75rem 1.25rem;
    background: var(--text-color);
    color: var(--bg-color);
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
}

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

.toast-error {
    background: var(--danger-color);
}

.toast-success {
    background: var(--success-color);
}