:root {
    /* Light theme variables */
    --color-bg: #ffffff;
    --color-text: #333333;
    --color-primary: #ff8c00;
    --color-secondary: #f5f5f5;
    --color-accent: #ff6b6b;
    --color-border: #e0e0e0;
    --color-card: #ffffff;
    --color-card-hover: #f8f9fa;
    --color-success: #28a745;
    --color-warning: #ffc107;
    --color-danger: #dc3545;
    --color-info: #ff8c00;
}

[data-theme="dark"] {
    --color-bg: #1a1a1a;
    --color-text: #e0e0e0;
    --color-primary: #ffa500;
    --color-secondary: #2d2d2d;
    --color-accent: #ff8a8a;
    --color-border: #404040;
    --color-card: #2d2d2d;
    --color-card-hover: #363636;
    --color-success: #4caf50;
    --color-warning: #ffb74d;
    --color-danger: #f44336;
    --color-info: #ffa500;
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    margin-bottom: 1rem;
    line-height: 1.2;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
}

/* Links */
a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color 0.3s;
}

a:hover {
    color: var(--color-accent);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    border: none;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

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

.btn-primary:hover {
    background-color: var(--color-accent);
}

/* Cards */
.card {
    background-color: var(--color-card);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* Forms */
input, select, textarea {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    background-color: var(--color-bg);
    color: var(--color-text);
    transition: border-color 0.3s;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--color-primary);
}

/* Layout */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Grid system */
.grid {
    display: grid;
    gap: 1rem;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Utility classes */
.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.mb-1 { margin-bottom: 1rem; }
.ml-1 { margin-left: 1rem; }
.mr-1 { margin-right: 1rem; }
.p-1 { padding: 1rem; }
.p-2 { padding: 2rem; }

/* Responsive design */
@media (max-width: 768px) {
    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }
    
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    h3 { font-size: 1.5rem; }
}