/* --- Root Variables (Dark Mode Theme) --- */
:root {
    --bg-dark: #0f0f1a;
    --bg-light: #1a1a2e;
    --text-primary: #f0f0f5;
    --text-secondary: #a0a0b5;
    --accent-glow: rgba(45, 130, 255, 0.6);
    --accent-gradient: linear-gradient(90deg, #6a11cb 0%, #2575fc 100%);
    --border-color: rgba(255, 255, 255, 0.1);
    --accent-blue: #2575fc;
    --success-color: #28a745;
}

/* --- General Reset & Body --- */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-primary);
    margin: 0;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    min-height: 100vh;
    background-image: radial-gradient(circle at top left, var(--bg-light) 0%, var(--bg-dark) 40%);
}

.container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 0 15px;
}

/* --- Header & Footer --- */
header {
    background-color: transparent;
    color: white;
    padding: 20px 0;
    text-align: center;
    width: 100%;
}

header h1 {
    font-size: 2rem;
    margin-bottom: 5px;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

header p {
    color: var(--text-secondary);
}

footer {
    text-align: center;
    padding: 20px 0;
    background-color: transparent;
    color: var(--text-secondary);
    margin-top: 30px;
    font-size: 0.9rem;
}

/* --- Breadcrumb --- */
.breadcrumb {
    padding: 15px;
    background-color: rgba(0,0,0,0.2);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 25px;
    font-size: 0.9rem;
}
.breadcrumb a {
    color: var(--accent-blue);
    text-decoration: none;
}
.breadcrumb a:hover {
    text-decoration: underline;
}
.breadcrumb span {
    color: var(--text-secondary);
}

/* --- Main Tool Container --- */
.tool-container {
    width: 100%;
    background: var(--bg-light);
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4), 0 0 0 1px rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    overflow: hidden; /* To contain the tab borders */
}

/* --- Tab Navigation --- */
.tabs {
    display: flex;
    background-color: var(--bg-dark);
    border-bottom: 1px solid var(--border-color);
}
.tab-link {
    padding: 15px 20px;
    border: none;
    background-color: transparent;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.2s ease-in-out;
    border-bottom: 3px solid transparent;
    flex-grow: 1; /* Makes tabs fill the space */
    text-align: center; /* Centers text in tab */
}
.tab-link:hover {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}
.tab-link.active {
    color: var(--text-primary);
    border-bottom: 3px solid var(--accent-blue);
}

/* --- Tab Content --- */
.tab-content {
    padding: 30px;
    display: none;
}
.tab-content.active {
    display: block;
}
.tab-content h2 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 15px;
    border-left: 3px solid var(--accent-blue);
    padding-left: 10px;
}
.tab-content p {
    margin-bottom: 20px;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

/* --- Form Elements --- */
.form-group {
    margin-bottom: 20px;
}
.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}
input[type="text"],
input[type="number"],
.file-input {
    width: 100%;
    padding: 12px;
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
}
.file-input {
    border-style: dashed;
    color: var(--text-secondary);
    cursor: pointer;
}
.options-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
}

/* --- Buttons --- */
.btn {
    display: block;
    width: 100%;
    padding: 15px;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 700;
    color: #fff;
    text-align: center;
    background: var(--accent-gradient);
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}
.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--accent-glow);
}

.download-btn {
    display: none; /* Hidden by default */
    margin-top: 20px;
    background: var(--success-color);
    color: white;
    padding: 15px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    text-align: center;
    font-size: 1.1rem;
    transition: all 0.3s ease;
}
.download-btn:hover {
    transform: translateY(-2px);
    background-color: #218838;
    box-shadow: 0 6px 20px rgba(40, 167, 69, 0.4);
}

/* --- Loader --- */
.loader {
    width: 30px;
    height: 30px;
    border: 4px solid var(--accent-blue);
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}
@keyframes spin {
    to { transform: rotate(360deg); }
}

/* --- SEO Content Section --- */
.content-section {
    background: var(--bg-light);
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4);
    border: 1px solid var(--border-color);
    padding: 30px;
    margin-top: 30px;
}
.content-section h2, .content-section h3 {
    color: var(--text-primary);
    margin-bottom: 10px;
    border-left: 3px solid var(--accent-blue);
    padding-left: 10px;
}
.content-section p {
    color: var(--text-secondary);
}
.content-section ul {
    margin-left: 20px;
    margin-bottom: 15px;
    color: var(--text-secondary);
}
.content-section li {
    margin-bottom: 8px;
}

/* --- Responsive --- */
@media (max-width: 768px) {
    body { padding: 10px; }
    
    .tabs {
        flex-direction: column;
    }
    .tab-link {
        border-bottom: 1px solid var(--border-color);
        text-align: left;
    }
    .tab-link.active {
        border-bottom: 3px solid var(--accent-blue);
    }
    header h1 {
        font-size: 1.8rem;
    }
    .btn, .download-btn {
        font-size: 1rem;
    }
    
    .tab-content, .content-section {
        padding: 20px;
    }
}