/* Main shared styles for hongq00.com */

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

h1 {
    font-size: 2.5rem;
    font-weight: 300;
}

h2 {
    font-size: 2rem;
    font-weight: 400;
}

h3 {
    font-size: 1.5rem;
    font-weight: 500;
}

p {
    margin-bottom: 1rem;
    color: #555;
}

/* Layout Components */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.header {
    background: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 1rem 0;
    margin-bottom: 2rem;
}

.header h1 {
    text-align: center;
    margin: 0;
}

.main-content {
    min-height: calc(100vh - 200px);
    padding: 2rem 0;
}

.footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}

/* Navigation Components */
.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    padding: 2rem 0;
}

.app-card {
    background: white;
    border-radius: 8px;
    padding: 2rem;
    text-decoration: none;
    color: inherit;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    border: 1px solid #e9ecef;
}

.app-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.15);
}

.app-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.app-card p {
    color: #6c757d;
    margin: 0;
}

/* Button Components */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.2s ease;
}

.btn:hover {
    background: #2980b9;
}

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

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

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

/* Loading and Error States */
.loading {
    text-align: center;
    padding: 2rem;
    color: #6c757d;
}

.error {
    background: #f8d7da;
    color: #721c24;
    padding: 1rem;
    border-radius: 4px;
    border: 1px solid #f5c6cb;
    margin: 1rem 0;
}

.success {
    background: #d4edda;
    color: #155724;
    padding: 1rem;
    border-radius: 4px;
    border: 1px solid #c3e6cb;
    margin: 1rem 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }

    .app-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .app-card {
        padding: 1.5rem;
    }

    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    h3 {
        font-size: 1.25rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 10px;
    }

    .app-card {
        padding: 1rem;
    }

    h1 {
        font-size: 1.75rem;
    }
}