/* ===================================
   CORSO JAVA - Stile Principale
   =================================== */

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
    overflow: hidden;
}

/* Header */
header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.1em;
    opacity: 0.95;
}

/* Navigazione */
nav {
    background: #f8f9fa;
    padding: 15px 30px;
    border-bottom: 3px solid #667eea;
}

nav a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    margin-right: 20px;
    transition: color 0.3s;
}

nav a:hover {
    color: #764ba2;
}

/* Contenuto principale */
main {
    padding: 40px;
}

h2 {
    color: #667eea;
    font-size: 2em;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 3px solid #667eea;
}

h3 {
    color: #764ba2;
    font-size: 1.5em;
    margin-top: 30px;
    margin-bottom: 15px;
}

h4 {
    color: #555;
    font-size: 1.2em;
    margin-top: 20px;
    margin-bottom: 10px;
}

p {
    margin-bottom: 15px;
    text-align: justify;
}

/* Box informativi */
.info-box {
    background: #e3f2fd;
    border-left: 5px solid #2196F3;
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
}

.warning-box {
    background: #fff3cd;
    border-left: 5px solid #ffc107;
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
}

.success-box {
    background: #d4edda;
    border-left: 5px solid #28a745;
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
}

.confronto-box {
    background: #f3e5f5;
    border-left: 5px solid #9c27b0;
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
}

/* Codice */
pre {
    background: #282c34;
    color: #abb2bf;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 20px 0;
    border-left: 5px solid #61dafb;
}

code {
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.95em;
}

.inline-code {
    background: #f4f4f4;
    color: #d63384;
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9em;
}

/* Liste */
ul, ol {
    margin: 15px 0 15px 30px;
}

li {
    margin-bottom: 10px;
}

/* Griglia lezioni */
.lezioni-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.lezione-card {
    background: white;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    padding: 25px;
    transition: all 0.3s;
    cursor: pointer;
    text-decoration: none;
    color: inherit;
    display: block;
}

.lezione-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.15);
    border-color: #667eea;
}

.lezione-numero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5em;
    font-weight: bold;
    margin-bottom: 15px;
}

.lezione-card h3 {
    color: #333;
    margin-top: 0;
    font-size: 1.3em;
}

.lezione-card p {
    color: #666;
    font-size: 0.95em;
    text-align: left;
}

/* Esercizi */
.esercizio {
    background: #f8f9fa;
    border-radius: 10px;
    padding: 20px;
    margin: 25px 0;
    border-left: 5px solid #28a745;
}

.esercizio h4 {
    color: #28a745;
    margin-top: 0;
}

.esercizio-difficolta {
    display: inline-block;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.85em;
    font-weight: bold;
    margin-bottom: 10px;
}

.facile {
    background: #d4edda;
    color: #155724;
}

.medio {
    background: #fff3cd;
    color: #856404;
}

.difficile {
    background: #f8d7da;
    color: #721c24;
}

/* Pulsanti */
.btn {
    display: inline-block;
    padding: 12px 25px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    margin: 10px 5px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
}

/* Footer */
footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px;
    margin-top: 40px;
}

/* Navigazione lezioni */
.nav-lezioni {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 30px;
    border-top: 2px solid #e0e0e0;
}

/* Responsive */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    main {
        padding: 20px;
    }
    
    header h1 {
        font-size: 1.8em;
    }
    
    .lezioni-grid {
        grid-template-columns: 1fr;
    }
    
    nav a {
        display: block;
        margin: 10px 0;
    }
    
    .nav-lezioni {
        flex-direction: column;
        gap: 10px;
    }
}

/* Tabelle */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

table th {
    background: #667eea;
    color: white;
    padding: 12px;
    text-align: left;
}

table td {
    padding: 10px;
    border-bottom: 1px solid #e0e0e0;
}

table tr:hover {
    background: #f8f9fa;
}

/* Output console */
.output {
    background: #1e1e1e;
    color: #d4d4d4;
    padding: 15px;
    border-radius: 5px;
    font-family: 'Courier New', Courier, monospace;
    margin: 15px 0;
    border-left: 5px solid #4ec9b0;
}

.output::before {
    content: "Output:";
    display: block;
    color: #4ec9b0;
    font-weight: bold;
    margin-bottom: 10px;
}