:root {
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-tertiary: #06b6d4;
    --border-color: rgba(0, 0, 0, 0.1);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    color: var(--text-primary);
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    margin-left: 1rem;
}

.search-input {
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    width: 300px;
}

.home-page {
    flex: 1;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.category-section {
    margin-bottom: 3rem;
}

.category-title {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
}

.tool-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.5rem;
}

.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.tool-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.tool-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.tool-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
    text-align: center;
}

.tool-page {
    flex: 1;
    padding: 2rem;
    max-width: 900px;
    margin: 0 auto;
    width: 100%;
}

.tool-title {
    font-size: 2rem;
    margin-bottom: 2rem;
}

.tool-content {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-sm);
}

.input-section, .output-section {
    margin-bottom: 1.5rem;
}

.input-box, .output-box {
    width: 100%;
    min-height: 200px;
    padding: 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: 'Fira Code', monospace;
    font-size: 1rem;
    resize: vertical;
}

.tool-buttons {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.btn {
    padding: 0.75rem 1.5rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    cursor: pointer;
}

.btn-primary {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: #fff;
}

.btn-secondary {
    background: var(--accent-secondary);
    border-color: var(--accent-secondary);
    color: #fff;
}

.color-preview, .gradient-preview {
    width: 100%;
    height: 150px;
    border-radius: var(--radius-md);
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

.color-inputs, .color-stops, .gradient-controls, .unit-converter, .base-converter {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.color-input-group, .color-stop, .unit-input-group, .base-input-group {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.color-input-group input, .base-input-group input {
    flex: 1;
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
}

.unit-inputs {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.unit-input-group input {
    width: 150px;
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
}

.password-display {
    font-size: 1.5rem;
    font-family: monospace;
    padding: 1.5rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    word-break: break-all;
}

.qr-display {
    display: flex;
    justify-content: center;
    padding: 2rem;
}

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 1.5rem;
    text-align: center;
    color: var(--text-muted);
}

input[type="text"],
input[type="number"],
textarea,
select {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

input[type="range"] {
    accent-color: var(--accent-primary);
}

input[type="checkbox"],
input[type="radio"] {
    accent-color: var(--accent-primary);
}