:root {
    /* Cores principais - azul e verde harmoniosos */
    --primary-blue: hsl(210, 75%, 45%);
    --primary-green: hsl(140, 60%, 45%);
    --light-blue: hsl(210, 75%, 95%);
    --light-green: hsl(140, 60%, 95%);
    --dark-blue: hsl(210, 75%, 25%);
    --dark-green: hsl(140, 60%, 25%);
    
    /* Cores complementares */
    --white: hsl(0, 0%, 100%);
    --light-gray: hsl(210, 11%, 98%);
    --gray: hsl(210, 7%, 56%);
    --dark-gray: hsl(210, 9%, 31%);
    --shadow: hsla(210, 75%, 25%, 0.1);
    
    /* Gradientes */
    --gradient-primary: linear-gradient(135deg, var(--primary-blue), var(--primary-green));
    --gradient-light: linear-gradient(135deg, var(--light-blue), var(--light-green));
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background: var(--light-gray);
    color: var(--dark-gray);
    line-height: 1.6;
}

/* Header */
.header-section {
    background: var(--gradient-primary);
    color: var(--white);
    padding: 2rem 0;
    box-shadow: 0 4px 6px var(--shadow);
}

.main-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.subtitle {
    font-size: 1.1rem;
    margin: 0.5rem 0 0 0;
    opacity: 0.9;
}

/* Main Content */
.main-content {
    padding: 3rem 0;
    min-height: calc(100vh - 200px);
}

/* Form Card */
.form-card {
    background: var(--white);
    border-radius: 12px;
    box-shadow: 0 8px 25px var(--shadow);
    margin-bottom: 2rem;
    overflow: hidden;
    border: 1px solid hsla(210, 75%, 45%, 0.1);
}

.form-card .card-header {
    background: var(--gradient-light);
    padding: 1.5rem;
    border-bottom: 1px solid hsla(210, 75%, 45%, 0.1);
}

.form-card .card-header h2,
.form-card .card-header h3 {
    color: var(--dark-blue);
    margin: 0;
    font-weight: 600;
}

.form-card .card-body {
    padding: 2rem;
}

/* Form Elements */
.form-label {
    font-weight: 600;
    color: var(--dark-gray);
    margin-bottom: 0.5rem;
}

.form-label.required::after {
    content: ' *';
    color: #dc3545;
}

.form-control {
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: var(--white);
}

.form-control:focus {
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 0.2rem hsla(210, 75%, 45%, 0.25);
    outline: none;
}

.form-control:invalid {
    border-color: #dc3545;
}

.form-control:valid {
    border-color: var(--primary-green);
}

/* Upload Area */
.upload-area {
    position: relative;
    border: 2px dashed var(--primary-blue);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    background: var(--light-blue);
    transition: all 0.3s ease;
}

.upload-area:hover {
    border-color: var(--dark-blue);
    background: hsl(210, 75%, 92%);
}

.upload-area input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.upload-info {
    pointer-events: none;
}

.upload-info i {
    font-size: 3rem;
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

.upload-info p {
    font-size: 1.1rem;
    color: var(--dark-blue);
    margin: 0.5rem 0;
    font-weight: 600;
}

.upload-info small {
    color: var(--gray);
    font-size: 0.9rem;
}

/* Buttons */
.btn-primary {
    background: var(--gradient-primary);
    border: none;
    border-radius: 8px;
    padding: 0.75rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--shadow);
    background: linear-gradient(135deg, var(--dark-blue), var(--dark-green));
}

.btn-outline-light {
    border: 2px solid var(--white);
    color: var(--white);
    border-radius: 8px;
    padding: 0.5rem 1.5rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-outline-light:hover {
    background: var(--white);
    color: var(--primary-blue);
    transform: translateY(-1px);
}

.btn-outline-primary {
    border: 2px solid var(--primary-blue);
    color: var(--primary-blue);
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-outline-primary:hover {
    background: var(--primary-blue);
    color: var(--white);
    transform: translateY(-1px);
}

/* Alerts */
.alert {
    border-radius: 8px;
    border: none;
    padding: 1rem 1.5rem;
    margin-bottom: 2rem;
    font-weight: 500;
}

.alert-success {
    background: var(--light-green);
    color: var(--dark-green);
    border-left: 4px solid var(--primary-green);
}

.alert-danger {
    background: hsl(0, 75%, 95%);
    color: hsl(0, 75%, 25%);
    border-left: 4px solid #dc3545;
}

/* Statistics */
.stat-item {
    padding: 1rem;
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-blue);
    margin: 0;
}

.stat-label {
    color: var(--gray);
    font-weight: 600;
    margin: 0.5rem 0 0 0;
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.5px;
}

/* Table */
.table {
    margin: 0;
}

.table th {
    background: var(--light-blue);
    color: var(--dark-blue);
    font-weight: 600;
    border: none;
    padding: 1rem;
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.5px;
}

.table td {
    padding: 1rem;
    border-top: 1px solid #e9ecef;
    vertical-align: middle;
}

.table-striped tbody tr:nth-of-type(odd) {
    background-color: hsl(210, 75%, 98%);
}

/* Footer */
.footer-section {
    background: var(--dark-gray);
    color: var(--white);
    padding: 1.5rem 0;
    margin-top: 2rem;
}

.footer-section p {
    margin: 0;
    opacity: 0.8;
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-title {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .form-card .card-body {
        padding: 1.5rem;
    }
    
    .upload-area {
        padding: 1.5rem;
    }
    
    .btn-primary {
        width: 100%;
    }
    
    .stat-number {
        font-size: 2rem;
    }
}

@media (max-width: 576px) {
    .header-section {
        padding: 1.5rem 0;
    }
    
    .main-content {
        padding: 2rem 0;
    }
    
    .form-card .card-body {
        padding: 1rem;
    }
    
    .upload-area {
        padding: 1rem;
    }
    
    .upload-info i {
        font-size: 2rem;
    }
    
    .upload-info p {
        font-size: 1rem;
    }
}

/* Animações */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.form-card {
    animation: fadeIn 0.6s ease-out;
}

/* Melhorias de acessibilidade */
.form-control:focus {
    outline: 3px solid hsla(210, 75%, 45%, 0.3);
    outline-offset: 2px;
}

.btn:focus {
    outline: 3px solid hsla(210, 75%, 45%, 0.3);
    outline-offset: 2px;
}

/* Estados de loading */
.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.loading {
    position: relative;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid transparent;
    border-top: 2px solid var(--white);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Estilo específico para alertas persistentes */
.persistent-alert {
    position: relative;
    animation: none !important;
    transition: none !important;
}

.persistent-alert.show {
    opacity: 1 !important;
    display: block !important;
}

.persistent-alert .btn-close {
    display: none !important;
}