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

:root {
    --primary: #FF6B35;
    --primary-dark: #E55A2B;
    --secondary: #00B894;
    --secondary-dark: #00A381;
    --accent: #0984E3;
    --accent-dark: #0770C2;
    --dark: #2D3436;
    --gray: #636E72;
    --light-gray: #DFE6E9;
    --bg-light: #F8F9FA;
    --white: #FFFFFF;
    --shadow: 0 4px 15px rgba(0,0,0,0.1);
    --shadow-hover: 0 8px 25px rgba(0,0,0,0.15);
    --radius: 12px;
    --radius-sm: 8px;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: var(--bg-light);
    min-height: 100vh;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Header & Navigation */
header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

nav {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo span {
    color: var(--secondary);
}

.nav-links {
    display: flex;
    gap: 35px;
    list-style: none;
}

.nav-links a {
    font-weight: 500;
    color: var(--gray);
    transition: color 0.3s;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s;
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: var(--dark);
    border-radius: 2px;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: var(--white);
    padding: 80px 20px;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.95;
    max-width: 700px;
    margin: 0 auto 30px;
}

.hero-btn {
    display: inline-block;
    background: var(--white);
    color: var(--primary);
    padding: 15px 40px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: transform 0.3s, box-shadow 0.3s;
}

.hero-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

/* Container */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 60px 20px;
}

/* Section Headers */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 2.2rem;
    color: var(--dark);
    margin-bottom: 15px;
}

.section-header p {
    color: var(--gray);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* Tool Cards */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 25px;
}

.tool-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 30px;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
    border: 2px solid transparent;
}

.tool-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary);
}

.tool-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    margin-bottom: 20px;
}

.tool-icon.text { background: #FFF3E0; color: var(--primary); }
.tool-icon.image { background: #E8F5E9; color: var(--secondary); }
.tool-icon.encoding { background: #E3F2FD; color: var(--accent); }
.tool-icon.convert { background: #FCE4EC; color: #E91E63; }
.tool-icon.color { background: #F3E5F5; color: #9C27B0; }
.tool-icon.number { background: #E0F7FA; color: #00BCD4; }
.tool-icon.date { background: #FBE9E7; color: #FF5722; }
.tool-icon.seo { background: #E8EAF6; color: #3F51B5; }
.tool-icon.dev { background: #F1F8E9; color: #689F38; }

.tool-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--dark);
}

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

/* Category Tabs */
.category-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: center;
    margin-bottom: 40px;
}

.category-tab {
    padding: 12px 25px;
    border-radius: 50px;
    background: var(--white);
    color: var(--gray);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid var(--light-gray);
}

.category-tab:hover,
.category-tab.active {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

/* Article Cards */
.article-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.article-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.article-card .content {
    padding: 25px;
}

.article-card .category {
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: 10px;
}

.article-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--dark);
}

.article-card p {
    color: var(--gray);
    font-size: 0.95rem;
    margin-bottom: 15px;
}

.article-card .read-more {
    color: var(--primary);
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

/* Tool Page Styles */
.tool-page {
    background: var(--white);
    border-radius: var(--radius);
    padding: 40px;
    box-shadow: var(--shadow);
}

.tool-page h1 {
    font-size: 2rem;
    margin-bottom: 10px;
    color: var(--dark);
}

.tool-page .tool-description {
    color: var(--gray);
    font-size: 1.1rem;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--light-gray);
}

.tool-input {
    width: 100%;
    padding: 15px;
    border: 2px solid var(--light-gray);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s;
    resize: vertical;
}

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

.tool-output {
    background: var(--bg-light);
    border-radius: var(--radius-sm);
    padding: 15px;
    margin-top: 20px;
    min-height: 100px;
    font-family: 'Courier New', monospace;
    word-break: break-all;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    border: none;
    font-size: 1rem;
}

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

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

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

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

.btn-group {
    display: flex;
    gap: 15px;
    margin-top: 20px;
    flex-wrap: wrap;
}

/* Form Styles */
.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--dark);
}

.form-control {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid var(--light-gray);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s;
}

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

/* Article Page */
.article-content {
    max-width: 800px;
    margin: 0 auto;
    background: var(--white);
    padding: 60px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.article-content h1 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--dark);
}

.article-content .meta {
    color: var(--gray);
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--light-gray);
}

.article-content h2 {
    font-size: 1.8rem;
    margin: 35px 0 15px;
    color: var(--dark);
}

.article-content h3 {
    font-size: 1.4rem;
    margin: 25px 0 10px;
    color: var(--dark);
}

.article-content p {
    margin-bottom: 20px;
    line-height: 1.8;
}

.article-content ul, .article-content ol {
    margin-bottom: 20px;
    padding-left: 25px;
}

.article-content li {
    margin-bottom: 10px;
}

.article-content img {
    max-width: 100%;
    border-radius: var(--radius-sm);
    margin: 25px 0;
}

.article-content code {
    background: var(--bg-light);
    padding: 3px 8px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    color: var(--primary);
}

.article-content pre {
    background: var(--dark);
    color: var(--white);
    padding: 20px;
    border-radius: var(--radius-sm);
    overflow-x: auto;
    margin: 20px 0;
}

.related-articles {
    margin-top: 60px;
    padding-top: 40px;
    border-top: 2px solid var(--light-gray);
}

/* Footer */
footer {
    background: var(--dark);
    color: var(--white);
    padding: 60px 20px;
    margin-top: 80px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
}

.footer-section h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--primary);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section a {
    color: var(--light-gray);
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    margin-top: 40px;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: var(--gray);
}

/* Page Headers */
.page-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: var(--white);
    padding: 60px 20px;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.page-header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* 404 Page */
.error-page {
    text-align: center;
    padding: 100px 20px;
}

.error-page h1 {
    font-size: 8rem;
    color: var(--primary);
    margin-bottom: 20px;
}

.error-page h2 {
    font-size: 2rem;
    margin-bottom: 20px;
}

.error-page p {
    color: var(--gray);
    margin-bottom: 30px;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        gap: 15px;
        box-shadow: var(--shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero h1 {
        font-size: 2rem;
    }

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

    .section-header h2 {
        font-size: 1.8rem;
    }

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

    .container {
        padding: 40px 15px;
    }

    .tool-page {
        padding: 25px;
    }

    .article-content {
        padding: 30px 20px;
    }

    .article-content h1 {
        font-size: 1.8rem;
    }
}

/* Utility Classes */
.text-center { text-align: center; }
.mt-20 { margin-top: 20px; }
.mt-30 { margin-top: 30px; }
.mb-20 { margin-bottom: 20px; }
.mb-30 { margin-bottom: 30px; }
.hidden { display: none; }

/* Color Picker Preview */
.color-preview {
    width: 100%;
    height: 80px;
    border-radius: var(--radius-sm);
    margin-top: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-weight: 600;
    font-size: 1.2rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

/* Table Styles */
.result-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.result-table th,
.result-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--light-gray);
}

.result-table th {
    background: var(--bg-light);
    font-weight: 600;
}

.result-table tr:hover {
    background: var(--bg-light);
}

/* JSON Editor */
.json-editor {
    font-family: 'Courier New', monospace;
    min-height: 300px;
    background: #1E1E1E;
    color: #D4D4D4;
    padding: 20px;
    border-radius: var(--radius-sm);
    overflow: auto;
}

/* Loading Spinner */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--light-gray);
    border-radius: 50%;
    border-top-color: var(--primary);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--dark);
    color: var(--white);
    padding: 15px 25px;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-hover);
    z-index: 9999;
    animation: slideIn 0.3s ease;
}

.toast.success { background: var(--secondary); }
.toast.error { background: #E74C3C; }

@keyframes slideIn {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.stat-item {
    background: var(--bg-light);
    padding: 20px;
    border-radius: var(--radius-sm);
    text-align: center;
}

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

.stat-item .label {
    color: var(--gray);
    font-size: 0.9rem;
}