/* ============================================
   FLASHLEARN NAVIGATION STYLES
   ============================================ */

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header Styles */
header {
    text-align: center;
    padding: 30px 20px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    margin-bottom: 30px;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 15px;
}

.logo-icon {
    font-size: 48px;
}

h1 {
    font-size: 2.8em;
    color: #2c3e50;
    font-weight: 700;
}

.tagline {
    font-size: 1.2em;
    color: #3498db;
    margin-bottom: 8px;
    font-weight: 500;
}

.sub-tagline {
    font-size: 1em;
    color: #7f8c8d;
}

/* Main Content */
main {
    flex: 1;
}

h2 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 30px;
    font-size: 1.8em;
}

/* Class Grid */
.class-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 25px;
    margin-bottom: 40px;
}

.class-card {
    background: white;
    border-radius: 15px;
    padding: 30px 20px;
    text-decoration: none;
    color: #333;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 3px solid transparent;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    min-height: 180px;
}

.class-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
    border-color: #3498db;
}

.class-number {
    font-size: 3.5em;
    font-weight: bold;
    color: #3498db;
    margin-bottom: 10px;
    line-height: 1;
}

.class-label {
    font-size: 1.3em;
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 8px;
}

.subject-count {
    font-size: 0.9em;
    color: #7f8c8d;
    background: #f8f9fa;
    padding: 4px 12px;
    border-radius: 20px;
}

/* Subject Grid */
.subject-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 25px;
    margin: 30px 0;
}

.subject-card {
    background: white;
    border-radius: 15px;
    padding: 25px 20px;
    text-decoration: none;
    color: #333;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 3px solid transparent;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    min-height: 200px;
}

.subject-card:hover:not(.coming-soon) {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
}

.subject-icon {
    font-size: 3em;
    margin-bottom: 15px;
}

.subject-name {
    font-size: 1.4em;
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 10px;
}

.subject-description {
    font-size: 0.9em;
    color: #7f8c8d;
    margin-bottom: 15px;
}

.subject-status {
    font-size: 0.9em;
    font-weight: 600;
    padding: 6px 15px;
    border-radius: 20px;
    display: inline-block;
}

/* Available Subjects */
.subject-card:not(.coming-soon) {
    border-color: #2ecc71;
}

.subject-card:not(.coming-soon):hover {
    border-color: #27ae60;
}

.subject-card:not(.coming-soon) .subject-status {
    background: #2ecc71;
    color: white;
}

/* Coming Soon Subjects */
.subject-card.coming-soon {
    opacity: 0.7;
    cursor: not-allowed;
    border-color: #f39c12;
}

.subject-card.coming-soon:hover {
    transform: none;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.subject-card.coming-soon .subject-status {
    background: #f39c12;
    color: white;
}

/* Back Button */
.back-button {
    display: inline-block;
    margin-bottom: 25px;
    padding: 10px 20px;
    background: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 25px;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid #3498db;
}

.back-button:hover {
    background: white;
    color: #3498db;
}

/* Footer */
footer {
    text-align: center;
    padding: 25px;
    color: #7f8c8d;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    margin-top: 30px;
}

/* Loading State */
.loading {
    grid-column: 1 / -1;
    text-align: center;
    padding: 40px;
    color: #7f8c8d;
    font-style: italic;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header {
        padding: 20px 15px;
    }
    
    h1 {
        font-size: 2.2em;
    }
    
    .class-grid,
    .subject-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 15px;
    }
    
    .class-card,
    .subject-card {
        padding: 20px 15px;
        min-height: 160px;
    }
    
    .class-number {
        font-size: 2.8em;
    }
    
    .subject-icon {
        font-size: 2.5em;
    }
}

@media (max-width: 480px) {
    .class-grid,
    .subject-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    h1 {
        font-size: 1.8em;
    }
    
    .tagline {
        font-size: 1em;
    }
}