:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --bg-dark: #0b1120;
    --bg-card: #151f32;
    --bg-card-hover: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #27354f;
    --accent: #10b981;
    --accent-purple: #8b5cf6;
    --ad-bg: rgba(30, 41, 59, 0.5);
    --ad-border: #3b4c68;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header & Navigation */
header {
    background-color: rgba(11, 17, 32, 0.95);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(12px);
}

.nav-container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0.8rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 1.4rem;
    font-weight: 800;
    color: #fff;
    text-decoration: none;
}

.logo-badge {
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    color: white;
    padding: 0.25rem 0.65rem;
    border-radius: 8px;
    font-size: 0.85rem;
    font-weight: 900;
    letter-spacing: 0.5px;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.35);
}

.nav-links {
    display: flex;
    gap: 1.4rem;
    align-items: center;
    list-style: none;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s ease;
}

.nav-links a:hover, .nav-links a.active {
    color: #fff;
}

.btn-header {
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    color: #fff !important;
    padding: 0.5rem 1.1rem;
    border-radius: 8px;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-header:hover {
    filter: brightness(1.1);
}

/* Ads Container Slot (AdSense Placeholder) */
.ad-slot {
    margin: 1.2rem auto;
    max-width: 1200px;
    min-height: 90px;
    background-color: var(--ad-bg);
    border: 1px dashed var(--ad-border);
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    text-align: center;
    padding: 0.8rem;
    backdrop-filter: blur(4px);
}

.ad-slot .ad-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    opacity: 0.7;
    margin-bottom: 4px;
    color: #64748b;
}

/* Main Container */
main {
    flex: 1;
    max-width: 1440px;
    width: 100%;
    margin: 0 auto;
    padding: 1rem 1.5rem 2rem;
}

/* Tool Navigation Switcher (Horizontal Scrolling Tabs) */
.tool-switcher-container {
    margin-bottom: 1.5rem;
}

.tool-switcher {
    display: flex;
    gap: 0.6rem;
    overflow-x: auto;
    padding-bottom: 0.6rem;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.tool-tab {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 0.65rem 1.2rem;
    border-radius: 9999px;
    font-size: 0.92rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.25s ease;
}

.tool-tab:hover {
    background-color: var(--bg-card-hover);
    color: #fff;
    border-color: #475569;
    transform: translateY(-1px);
}

.tool-tab.active {
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    color: #fff;
    border-color: #3b82f6;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.4);
}

/* Editor Fullscreen Frame */
.editor-wrapper {
    background-color: #1e1e1e;
    border: 1px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.7);
    height: 860px;
    width: 100%;
    position: relative;
}

.editor-wrapper iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

/* Utility Tools Layout (Compressor, Converter, Resizer, Filters, Watermark) */
.tool-card {
    background: linear-gradient(180deg, #151f32 0%, #101827 100%);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 10px 30px -10px rgba(0,0,0,0.5);
}

.tool-card h2 {
    font-size: 1.8rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 0.5rem;
}

.tool-card .tool-desc {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 2rem;
}

.upload-area {
    border: 2px dashed #3b4c68;
    border-radius: 14px;
    padding: 3.5rem 1.5rem;
    text-align: center;
    cursor: pointer;
    background-color: rgba(11, 17, 32, 0.4);
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.upload-area:hover, .upload-area.dragover {
    border-color: var(--primary-color);
    background-color: rgba(59, 130, 246, 0.08);
    transform: scale(0.995);
}

.upload-icon {
    font-size: 3.2rem;
    margin-bottom: 0.8rem;
    display: inline-block;
}

.upload-area h3 {
    font-size: 1.25rem;
    color: #f1f5f9;
}

.control-panel {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    align-items: flex-end;
}

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

.form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-main);
    display: flex;
    justify-content: space-between;
}

.form-group select, .form-group input[type="text"], .form-group input[type="number"], .form-group input[type="color"] {
    background-color: #0b1120;
    border: 1px solid var(--border-color);
    color: #fff;
    padding: 0.75rem 1rem;
    border-radius: 8px;
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

.form-group select:focus, .form-group input:focus {
    border-color: var(--primary-color);
}

.form-group input[type="range"] {
    accent-color: var(--primary-color);
    cursor: pointer;
    height: 6px;
    border-radius: 4px;
    background: #27354f;
}

.btn-primary {
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    color: #fff;
    border: none;
    padding: 0.85rem 1.8rem;
    border-radius: 10px;
    font-weight: 600;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
}

.btn-secondary {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    color: #fff;
    padding: 0.75rem 1.4rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

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

/* Action tool buttons grid (Rotate, Flip, Invert) */
.btn-grid-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    margin-top: 1.5rem;
}

/* Preview Grid & Container */
.preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.preview-box {
    background-color: #0b1120;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

.preview-box h4 {
    color: #94a3b8;
    margin-bottom: 1rem;
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.preview-box img, .preview-box canvas {
    max-width: 100%;
    max-height: 300px;
    border-radius: 8px;
    object-fit: contain;
    margin-bottom: 1rem;
    border: 1px solid var(--border-color);
    background-image: 
        linear-gradient(45deg, #1e293b 25%, transparent 25%), 
        linear-gradient(-45deg, #1e293b 25%, transparent 25%), 
        linear-gradient(45deg, transparent 75%, #1e293b 75%), 
        linear-gradient(-45deg, transparent 75%, #1e293b 75%);
    background-size: 16px 16px;
    background-position: 0 0, 0 8px, 8px -8px, -8px 0px;
}

/* SEO Content Section */
.seo-section {
    background: linear-gradient(180deg, #151f32 0%, #101827 100%);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2.5rem;
    margin-top: 2.5rem;
}

.seo-section h1, .seo-section h2, .seo-section h3 {
    color: #fff;
    margin-bottom: 1rem;
}

.seo-section h2 {
    margin-top: 2.2rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.6rem;
}

.seo-section p, .seo-section ul, .seo-section ol {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 1.2rem;
}

.seo-section ul, .seo-section ol {
    padding-left: 1.5rem;
}

.seo-section li {
    margin-bottom: 0.5rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.feature-item {
    background-color: #0b1120;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
}

.feature-item h4 {
    color: #fff;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
}

/* Footer */
footer {
    background-color: #080c16;
    border-top: 1px solid var(--border-color);
    padding: 3.5rem 1.5rem 1.5rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1440px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2.5rem;
    margin-bottom: 2.5rem;
}

.footer-col h5 {
    color: #fff;
    font-size: 1.15rem;
    margin-bottom: 1.2rem;
}

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

.footer-col ul li {
    margin-bottom: 0.7rem;
}

.footer-col ul li a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.2s;
}

.footer-col ul li a:hover {
    color: #fff;
}

.footer-bottom {
    max-width: 1440px;
    margin: 0 auto;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
}

@media (max-width: 768px) {
    .editor-wrapper {
        height: 600px;
    }
    .nav-links {
        display: none;
    }
    .control-panel {
        grid-template-columns: 1fr;
    }
}