:root {
    --bg: #0f0f1a;
    --bg-card: #1a1a2e;
    --bg-input: #16213e;
    --text: #e0e0e0;
    --text-muted: #8888aa;
    --primary: #6c63ff;
    --primary-hover: #5a52d9;
    --primary-light: rgba(108, 99, 255, 0.1);
    --success: #4ade80;
    --warning: #fbbf24;
    --danger: #ef4444;
    --border: #2a2a4a;
    --radius: 12px;
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
    --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --mono: 'SF Mono', 'Fira Code', 'Monaco', monospace;
}

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

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

/* Navbar */
.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.nav-logo {
    font-size: 1.2rem;
    font-weight: 700;
    text-decoration: none;
    color: var(--text);
    white-space: nowrap;
}

.nav-links {
    display: flex;
    gap: 0.3rem;
    flex-wrap: wrap;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    padding: 0.4rem 0.8rem;
    border-radius: 8px;
    font-size: 0.85rem;
    transition: all 0.2s;
    white-space: nowrap;
}

.nav-links a:hover { color: var(--text); background: var(--primary-light); }
.nav-links a.active { color: var(--primary); background: var(--primary-light); font-weight: 600; }

/* Container */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

/* Tool header */
.tool-header { text-align: center; margin-bottom: 2rem; }
.tool-header h1 { font-size: 2rem; margin-bottom: 0.5rem; }
.subtitle { color: var(--text-muted); font-size: 1.1rem; }

/* Tool card */
.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    margin-bottom: 1.5rem;
}

/* Upload zone */
.upload-zone {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
}

.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.upload-zone.dragover { transform: scale(1.02); }

.upload-icon { color: var(--text-muted); margin-bottom: 1rem; }

.upload-text { font-size: 1.1rem; margin-bottom: 0.5rem; }
.upload-text .link { color: var(--primary); text-decoration: underline; }

.upload-hint { color: var(--text-muted); font-size: 0.85rem; }

.upload-zone.compact { padding: 1.5rem; }
.upload-zone.compact .upload-icon { width: 32px; height: 32px; }

/* Tool options */
.tool-options { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 2rem; margin-bottom: 1.5rem; }

.option-group { margin-bottom: 1.5rem; }
.option-group label { display: block; margin-bottom: 0.5rem; font-weight: 500; font-size: 0.9rem; }

.quality-buttons { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.quality-btn {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border);
    background: var(--bg-input);
    color: var(--text-muted);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
    min-width: 100px;
}
.quality-btn:hover { border-color: var(--primary); color: var(--text); }
.quality-btn.active { background: var(--primary); color: white; border-color: var(--primary); }

/* Inputs */
.text-input {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-size: 1rem;
    font-family: var(--font);
    transition: border-color 0.2s;
}
.text-input:focus { outline: none; border-color: var(--primary); }

.color-input { width: 100%; height: 44px; border: 1px solid var(--border); border-radius: 8px; cursor: pointer; background: var(--bg-input); padding: 4px; }

select.text-input { cursor: pointer; }

.text-area {
    width: 100%;
    padding: 1rem;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-size: 1rem;
    font-family: var(--font);
    resize: vertical;
    min-height: 150px;
    transition: border-color 0.2s;
}
.text-area:focus { outline: none; border-color: var(--primary); }

/* Buttons */
.btn-primary {
    display: block;
    width: 100%;
    padding: 0.9rem 1.5rem;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}
.btn-primary:hover:not(:disabled) { background: var(--primary-hover); transform: translateY(-1px); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }

.btn-download {
    display: block;
    text-align: center;
    padding: 0.9rem 1.5rem;
    background: var(--success);
    color: #0f0f1a;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 700;
    font-size: 1rem;
    margin: 1rem 0;
    transition: all 0.2s;
}
.btn-download:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(74, 222, 128, 0.3); }

.btn-secondary {
    display: block;
    width: 100%;
    padding: 0.75rem;
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
}
.btn-secondary:hover { color: var(--text); border-color: var(--primary); }

/* Result */
.result-section { animation: fadeIn 0.3s ease; }
.result-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 2rem; text-align: center; }
.result-card h3 { color: var(--success); margin-bottom: 1.5rem; font-size: 1.3rem; }

.result-stats { display: flex; justify-content: center; gap: 1rem; margin-bottom: 1.5rem; flex-wrap: wrap; }
.stat { background: var(--bg-input); padding: 1rem 1.5rem; border-radius: 8px; min-width: 100px; }
.stat-label { display: block; color: var(--text-muted); font-size: 0.8rem; margin-bottom: 0.25rem; }
.stat-value { display: block; font-size: 1.2rem; font-weight: 700; }
.stat.highlight .stat-value { color: var(--success); }

.image-preview img { max-width: 100%; border-radius: 8px; margin: 1rem 0; }
.qr-preview { text-align: center; margin: 1.5rem 0; }

/* Stats grid (contador palabras) */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(100px, 1fr)); gap: 1rem; margin-top: 1.5rem; }
.stat-box { background: var(--bg-input); border-radius: 8px; padding: 1rem; text-align: center; }
.stat-box .stat-num { display: block; font-size: 1.8rem; font-weight: 700; color: var(--primary); }
.stat-box .stat-label { display: block; font-size: 0.75rem; color: var(--text-muted); margin-top: 0.25rem; }

/* Keywords */
.keywords-section { margin-top: 2rem; }
.keywords-section h3 { margin-bottom: 0.75rem; }
.keywords-list { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.keyword-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg-input);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-size: 0.85rem;
}
.keyword-word { font-weight: 600; }
.keyword-count { color: var(--text-muted); }
.keyword-density { color: var(--primary); font-weight: 600; }

/* File list */
.file-list-section h3 { margin-bottom: 1rem; }
.file-list { list-style: none; margin-bottom: 1.5rem; }
.file-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--bg-input);
    border-radius: 8px;
    margin-bottom: 0.5rem;
    border: 1px solid var(--border);
}
.file-item .file-icon { font-size: 1.2rem; }
.file-item .file-name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-item .file-size { color: var(--text-muted); font-size: 0.85rem; }
.file-item .file-remove { background: none; border: none; color: var(--danger); cursor: pointer; font-size: 1.1rem; padding: 0.25rem 0.5rem; }

/* Form helpers */
.form-group { margin-bottom: 1rem; }
.form-group label { display: block; margin-bottom: 0.4rem; font-weight: 500; font-size: 0.9rem; }
.form-row { display: flex; gap: 1rem; flex-wrap: wrap; }
.form-row .form-group { flex: 1; min-width: 120px; }

/* SEO content */
.seo-content { margin-top: 3rem; line-height: 1.7; }
.seo-content h2 { font-size: 1.5rem; margin: 2rem 0 0.75rem; }
.seo-content h3 { font-size: 1.2rem; margin: 1.5rem 0 0.5rem; color: var(--primary); }
.seo-content p { margin-bottom: 1rem; color: var(--text-muted); }
.seo-content ul { margin-bottom: 1rem; padding-left: 1.5rem; }
.seo-content li { margin-bottom: 0.4rem; color: var(--text-muted); }
.seo-content strong { color: var(--text); }

/* Footer */
.footer { text-align: center; padding: 2rem; color: var(--text-muted); border-top: 1px solid var(--border); margin-top: 3rem; }

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    z-index: 1000;
    opacity: 0;
    transition: all 0.3s;
}
.toast.show { transform: translateX(-50%) translateY(0); opacity: 1; }

/* Animations */
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

/* Tools grid (landing page) */
.section-title {
    font-size: 1.3rem;
    margin: 2.5rem 0 1rem;
    color: var(--primary);
}
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
    margin-bottom: 1rem;
}
.tool-card-link {
    text-decoration: none;
    color: inherit;
}
.tool-card-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: all 0.3s;
    height: 100%;
}
.tool-card-link:hover .tool-card-item {
    border-color: var(--primary);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(108, 99, 255, 0.15);
}
.tool-card-item .tool-icon {
    font-size: 2rem;
    display: block;
    margin-bottom: 0.75rem;
}
.tool-card-item h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}
.tool-card-item p {
    color: var(--text-muted);
    font-size: 0.85rem;
    line-height: 1.5;
}

/* Responsive */
@media (max-width: 640px) {
    .tool-header h1 { font-size: 1.5rem; }
    .subtitle { font-size: 0.95rem; }
    .tool-card, .tool-options, .result-card { padding: 1.25rem; }
    .quality-btn { min-width: 80px; font-size: 0.8rem; }
    .result-stats { gap: 0.5rem; }
    .stat { min-width: 80px; padding: 0.75rem; }
    .nav-links a { padding: 0.3rem 0.5rem; font-size: 0.8rem; }
}