:root {
    --primary: #4361ee;
    --secondary: #3a0ca3;
    --success: #4cc9f0;
    --danger: #f72585;
    --warning: #fca311;
    --light: #f8f9fa;
    --dark: #212529;
    --gray: #6c757d;
    --background: #ffffff;
    --card-bg: #ffffff;
    --text: #333333;
    --border: #dee2e6;
    --card-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --card-hover-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
}

.dark-mode {
    --primary: #4cc9f0;
    --secondary: #4361ee;
    --background: #121212;
    --card-bg: #1e1e1e;
    --text: #f8f9fa;
    --border: #343a40;
    --card-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    --card-hover-shadow: 0 6px 16px rgba(0, 0, 0, 0.4);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    transition: background-color 0.3s, color 0.3s, box-shadow 0.3s, transform 0.2s;
}

body {
    background-color: var(--background);
    color: var(--text);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid var(--border);
    margin-bottom: 30px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text);
    cursor: pointer;
    font-size: 20px;
    padding: 8px;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    background-color: rgba(0, 0, 0, 0.05);
}

.dark-mode .theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.add-task-form {
    background-color: var(--card-bg);
    padding: 25px;
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    margin-bottom: 30px;
}

.add-task-form h2 {
    margin-bottom: 20px;
    color: var(--primary);
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text);
}

input, textarea {
    width: 100%;
    padding: 14px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background-color: var(--background);
    color: var(--text);
    font-size: 16px;
    transition: border-color 0.3s;
}

input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
}

textarea {
    min-height: 100px;
    resize: vertical;
}

button {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 14px 24px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.form-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

button:hover {
    background-color: var(--secondary);
    transform: translateY(-2px);
}

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

.btn-danger:hover {
    background-color: #d1144a;
    transform: translateY(-2px);
}

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

.btn-success:hover {
    background-color: #3aa8d0;
    transform: translateY(-2px);
}

.filters {
    display: flex;
    gap: 12px;
    margin-bottom: 25px;
    flex-wrap: wrap;
}

.filter-btn {
    background-color: var(--card-bg);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 10px 20px;
}

.filter-btn.active {
    background-color: var(--primary);
    color: white;
    border-color: var(--primary);
}

.tarefas-container {
    margin-bottom: 40px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.tarefa-card {
    background-color: var(--card-bg);
    border-radius: 16px;
    padding: 0;
    box-shadow: var(--card-shadow);
    overflow: hidden;
    transition: all 0.3s;
    border-left: 4px solid var(--primary);
}

.tarefa-card:hover {
    box-shadow: var(--card-hover-shadow);
    transform: translateY(-2px);
}

.tarefa-concluida {
    opacity: 0.8;
    border-left-color: var(--success);
}

.tarefa-concluida .tarefa-titulo {
    text-decoration: line-through;
    color: var(--gray);
}

.tarefa-header {
    padding: 20px 20px 0;
    display: flex;
    align-items: flex-start;
    gap: 12px;
    cursor: pointer;
}

.tarefa-status {
    font-size: 20px;
    margin-top: 4px;
    flex-shrink: 0;
    color: var(--gray);
    transition: color 0.2s;
}

.tarefa-status:hover {
    color: var(--success);
}

.tarefa-titulo {
    font-size: 18px;
    font-weight: 600;
    margin: 0;
    flex: 1;
    word-break: break-word;
}

.tarefa-body {
    padding: 10px 20px 0;
}

.tarefa-descricao {
    color: var(--gray);
    margin-bottom: 10px;
    font-size: 15px;
    line-height: 1.5;
    word-break: break-word;
}

.tarefa-descricao.vazio {
    font-style: italic;
    opacity: 0.7;
}

.tarefa-footer {
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    background-color: rgba(0, 0, 0, 0.02);
    border-top: 1px solid var(--border);
}

.dark-mode .tarefa-footer {
    background-color: rgba(255, 255, 255, 0.03);
}

.tarefa-data {
    font-size: 13px;
    color: var(--gray);
}

.tarefa-acoes {
    display: flex;
    gap: 8px;
}

.action-btn {
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--gray);
}

.empty-state i {
    font-size: 64px;
    margin-bottom: 20px;
    color: var(--border);
    opacity: 0.5;
}

.empty-state h3 {
    margin-bottom: 10px;
    font-weight: 600;
}

footer {
    text-align: center;
    padding: 20px;
    margin-top: auto;
    color: var(--gray);
    font-size: 14px;
    border-top: 1px solid var(--border);
}

/* Animações */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
    from { 
        opacity: 0; 
        transform: translateX(100%); 
    }
    to { 
        opacity: 1; 
        transform: translateX(0); 
    }
}

@keyframes slideOut {
    from { 
        opacity: 1; 
        transform: translateX(0); 
    }
    to { 
        opacity: 0; 
        transform: translateX(100%); 
    }
}

.tarefa-card {
    animation: fadeIn 0.3s ease-out;
}

/* Responsividade */
@media (max-width: 600px) {
    .container {
        padding: 15px;
    }
    
    .tarefa-footer {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .tarefa-acoes {
        width: 100%;
        justify-content: flex-end;
    }
    
    .filters {
        justify-content: center;
    }
    
    .add-task-form {
        padding: 20px;
    }
}