/* --- Global Styles & Variables --- */
:root {
    --primary: #0077ff;
    --primary-hover: #0056b3;
    --secondary: #28a745;
    --danger: #dc3545;
    --bg-main: #f4f7fa;
    --card-bg: #ffffff;
    --text-dark: #1d1d1f;
    --text-muted: #636e72;
    --border-color: #e2e8f0;
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
}

* {
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Plus Jakarta Sans', 'Inter', system-ui, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-dark);
    line-height: 1.6;
}

/* --- Navigation --- */
.nav-bar {
    background: #ffffff;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.brand {
    font-weight: 800;
    font-size: 1.4rem;
    text-decoration: none;
    color: var(--text-dark);
}

.brand span { color: var(--primary); }

/* --- Layout Container --- */
.container {
    max-width: 1000px;
    margin: 40px auto;
    padding: 0 20px;
}

.tool-wrapper {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 24px;
    box-shadow: var(--shadow);
    text-align: center;
}

/* --- Header --- */
.main-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 10px;
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
    margin-bottom: 40px;
}

/* --- Upload Area --- */
.upload-area {
    border: 2px dashed #cbd5e1;
    background: #f8fafc;
    padding: 60px 20px;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s ease-in-out;
    position: relative;
    margin-bottom: 30px;
}

.upload-area:hover, .upload-area.drag-over {
    border-color: var(--primary);
    background: #f0f7ff;
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 15px;
    display: block;
}

input[type="file"] {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

/* --- Buttons --- */
.action-buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin: 30px 0;
    flex-wrap: wrap;
}

.btn {
    padding: 14px 28px;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    border: none;
    transition: 0.2s transform active;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 1rem;
}

.btn:disabled { opacity: 0.6; cursor: not-allowed; }
.btn-primary { background: var(--primary); color: white; box-shadow: 0 4px 14px rgba(0, 119, 255, 0.3); }
.btn-primary:hover { background: var(--primary-hover); }
.btn-danger { background: var(--danger); color: white; }
.btn-outline { background: transparent; border: 2px solid var(--border-color); color: var(--primary); }

/* --- Preview & Output --- */
#previewCanvas {
    max-width: 250px;
    height: auto;
    border-radius: 12px;
    margin: 20px auto;
    box-shadow: 0 10px 15px -3px rgba(0,0,0,0.1);
}

.output-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 25px;
    margin-top: 40px;
}

.page-card {
    background: white;
    border: 1px solid var(--border-color);
    padding: 12px;
    border-radius: 16px;
    transition: 0.3s;
}

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

.page-card img {
    width: 100%;
    border-radius: 10px;
    margin-bottom: 12px;
}

.card-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.btn-sm {
    text-decoration: none;
    background: #f1f5f9;
    color: var(--primary);
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 0.8rem;
    font-weight: 700;
}

/* --- Loader Spinner --- */
.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

/* --- SEO Content Section --- */
.content-section {
    margin-top: 60px;
    padding-top: 40px;
    border-top: 1px solid var(--border-color);
}

.step-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 30px 0;
}

.step {
    background: white;
    padding: 20px;
    border-radius: 15px;
    text-align: center;
}

.step span {
    display: inline-block;
    width: 30px; height: 30px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    line-height: 30px;
    font-weight: bold;
    margin-bottom: 10px;
}

/* --- Ads & Footer --- */
.ad-slot {
    margin: 30px 0;
    background: #ebeef2;
    border-radius: 12px;
    min-height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #a0aec0;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

footer {
    background: #fff;
    padding: 40px 0;
    margin-top: 80px;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-links a {
    margin: 0 10px;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
}

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

/* --- Responsive --- */
@media (max-width: 768px) {
    .step-grid { grid-template-columns: 1fr; }
    .main-header h1 { font-size: 1.8rem; }
    .tool-wrapper { padding: 25px 15px; }
}