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

:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --primary-dark: #2563eb;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --background-color: #f8fafc;
    --text-color: #1e293b;
    --text-light: #64748b;
    --border-color: #e2e8f0;
    --white: #ffffff;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

.header {
    background-color: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo h1 {
    font-size: 1.25rem;
    color: var(--primary-color);
    font-weight: 600;
    margin: 0;
}

.logo-link {
    text-decoration: none;
    color: inherit;
    transition: opacity 0.2s;
}

.logo-link:hover {
    opacity: 0.8;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.auth-buttons {
    display: flex;
    gap: 0.5rem;
}

.btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.25rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    display: inline-block;
    font-size: 0.875rem;
}

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

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

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

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

.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

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

.btn-danger {
    background-color: #ef4444;
    color: var(--white);
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-full {
    width: 100%;
}

.intro {
    padding: 3rem 0;
    background-color: var(--white);
    border-bottom: 1px solid var(--border-color);
}

.intro-title {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.intro-description {
    color: var(--text-light);
    font-size: 1rem;
}

.tools {
    padding: 2rem 0;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.tool-card {
    background-color: var(--white);
    padding: 1.5rem;
    border-radius: 0.375rem;
    border: 1px solid var(--border-color);
    transition: box-shadow 0.2s;
}

.tool-card:hover {
    box-shadow: var(--shadow-lg);
}

.tool-icon {
    font-size: 2rem;
    margin-bottom: 0.75rem;
}

.tool-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.tool-description {
    color: var(--text-light);
    font-size: 0.875rem;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.tool-btn {
    margin-top: 0.5rem;
    font-size: 0.875rem;
}

.auth-badge {
    display: inline-block;
    background-color: #f59e0b;
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.footer {
    background-color: var(--white);
    color: var(--text-light);
    padding: 1.5rem 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.875rem;
}

.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.2s;
}

.modal.show {
    display: flex;
    justify-content: center;
    align-items: center;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.modal-content {
    background-color: var(--white);
    padding: 1.5rem;
    border-radius: 0.375rem;
    width: 90%;
    max-width: 380px;
    position: relative;
    animation: slideIn 0.2s;
}

@keyframes slideIn {
    from {
        transform: translateY(-30px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-close {
    position: absolute;
    right: 1rem;
    top: 1rem;
    font-size: 1.25rem;
    cursor: pointer;
    color: var(--text-light);
    transition: color 0.2s;
}

.modal-close:hover {
    color: var(--text-color);
}

.modal-title {
    text-align: center;
    margin-bottom: 1.25rem;
    color: var(--text-color);
    font-size: 1.25rem;
    font-weight: 600;
}

.auth-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 500;
    color: var(--text-color);
    font-size: 0.875rem;
}

.form-group input {
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
    font-size: 0.875rem;
    transition: border-color 0.2s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.auth-switch {
    text-align: center;
    margin-top: 0.75rem;
    color: var(--text-light);
    font-size: 0.875rem;
}

.auth-switch a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.auth-switch a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .tools-grid {
        grid-template-columns: 1fr;
    }
}