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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --success-color: #10b981;
    --error-color: #ef4444;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    box-shadow: var(--shadow-sm);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover {
    color: var(--primary-color);
}

/* Main Container */
main {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 3rem 1.5rem;
    width: 100%;
}

/* Homepage Hero */
.hero {
    text-align: center;
    margin-bottom: 4rem;
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Tool Grid */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.tool-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
    box-shadow: var(--shadow-sm);
}

.tool-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
    border-color: var(--primary-color);
}

.tool-card h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.tool-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

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

/* Tool Page Layout */
.tool-page {
    max-width: 900px;
    margin: 0 auto;
}

.breadcrumb {
    margin-bottom: 2rem;
    font-size: 0.9rem;
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

.breadcrumb span {
    color: var(--text-secondary);
    margin: 0 0.5rem;
}

.tool-header {
    margin-bottom: 2rem;
}

.tool-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
}

.tool-header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* Tool Container */
.tool-container {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-md);
    margin-bottom: 3rem;
}

/* Form Elements */
.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

textarea,
input[type="text"],
input[type="number"],
select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 0.95rem;
    background: var(--bg-primary);
    transition: border-color 0.2s, box-shadow 0.2s;
}

textarea {
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    resize: vertical;
    min-height: 200px;
}

textarea:focus,
input:focus,
select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Buttons */
.btn-group {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

button,
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    background: var(--primary-color);
    color: white;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

button:hover,
.btn:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

button:active,
.btn:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

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

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

.btn-success:hover {
    background: #059669;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Output Area */
.output-area {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    margin-top: 1rem;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    white-space: pre-wrap;
    word-break: break-all;
    min-height: 100px;
}

/* Stats Display */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 1.5rem;
}

.stat-card {
    background: var(--bg-secondary);
    padding: 1rem;
    border-radius: var(--radius-md);
    text-align: center;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* List Items */
.uuid-list {
    list-style: none;
    margin-top: 1.5rem;
}

.uuid-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem;
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
    margin-bottom: 0.5rem;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
}

.uuid-item button {
    padding: 0.375rem 0.75rem;
    font-size: 0.85rem;
}

/* Color Preview */
.color-preview {
    width: 100%;
    height: 100px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-top: 1rem;
}

/* Cron Expression Display */
.cron-display {
    background: var(--bg-secondary);
    border: 2px solid var(--primary-color);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    margin: 1.5rem 0;
    text-align: center;
}

.cron-expression {
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.cron-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Preset Buttons */
.preset-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.preset-btn {
    padding: 0.625rem 1rem;
    font-size: 0.875rem;
}

/* Diff Checker */
.diff-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.diff-output {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.8;
    white-space: pre-wrap;
    word-break: break-all;
}

.diff-added {
    background-color: #d1fae5;
    color: #065f46;
}

.diff-removed {
    background-color: #fee2e2;
    color: #991b1b;
}

.diff-line {
    padding: 0.125rem 0.5rem;
    margin: 0.125rem 0;
}

/* Alert Messages */
.alert {
    padding: 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    border-left: 4px solid;
}

.alert-error {
    background: #fef2f2;
    border-color: var(--error-color);
    color: #991b1b;
}

.alert-success {
    background: #f0fdf4;
    border-color: var(--success-color);
    color: #065f46;
}

/* FAQ Section */
.faq-section {
    margin-top: 4rem;
}

.faq-section h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
}

.faq-item {
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow-sm);
}

.faq-item h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.faq-item p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Footer */
footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    margin-top: auto;
    padding: 2rem 0;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    text-align: center;
}

.footer-links {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
}

.footer-links a:hover {
    color: var(--primary-color);
}

.copyright {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .tool-grid {
        grid-template-columns: 1fr;
    }

    .tool-header h1 {
        font-size: 2rem;
    }

    .diff-container {
        grid-template-columns: 1fr;
    }

    nav ul {
        gap: 1rem;
    }

    .header-container {
        flex-direction: column;
        gap: 1rem;
    }

    .btn-group {
        flex-direction: column;
    }

    button,
    .btn {
        width: 100%;
        justify-content: center;
    }

    .preset-group {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    main {
        padding: 2rem 1rem;
    }

    .tool-container {
        padding: 1.5rem;
    }

    .stats {
        grid-template-columns: 1fr 1fr;
    }
}

/* Loading State */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

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

.mt-1 {
    margin-top: 0.5rem;
}

.mt-2 {
    margin-top: 1rem;
}

.mb-1 {
    margin-bottom: 0.5rem;
}

.mb-2 {
    margin-bottom: 1rem;
}

.hidden {
    display: none;
}