/* ===== CSS Variables / Theme ===== */
:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --primary-light: #eef2ff;
    --secondary: #0ea5e9;
    --success: #22c55e;
    --warning: #f59e0b;
    --error: #ef4444;
    --bg: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: #ffffff;
    --text: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border: #e2e8f0;
    --border-light: #f1f5f9;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --max-width: 1200px;
}

/* ===== Reset ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

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

img {
    max-width: 100%;
    height: auto;
}

/* ===== Layout ===== */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== Header ===== */
.header {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--primary);
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 18px;
}

.nav {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav a {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.2s;
}

.nav a:hover {
    background: var(--bg-secondary);
    color: var(--text);
}

.nav a.active {
    background: var(--primary-light);
    color: var(--primary);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--text);
}

/* ===== Hero Section ===== */
.hero {
    text-align: center;
    padding: 60px 20px;
    background: linear-gradient(135deg, var(--primary-light), #f0f9ff);
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 16px;
}

.hero p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 24px;
}

.hero-badges {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    background: var(--bg);
    border-radius: 100px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    box-shadow: var(--shadow);
}

/* ===== Tools Grid ===== */
.tools-section {
    padding: 48px 0;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text);
}

.section-desc {
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-size: 0.95rem;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    transition: all 0.2s ease;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.tool-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.tool-card-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.tool-card-icon.image { background: #fef3c7; }
.tool-card-icon.pdf { background: #fee2e2; }
.tool-card-icon.convert { background: #dbeafe; }
.tool-card-icon.text { background: #d1fae5; }
.tool-card-icon.dev { background: #ede9fe; }
.tool-card-icon.qr { background: #dbeafe; }

.tool-card h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
}

.tool-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.tool-card-tag {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 100px;
    font-size: 11px;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text-muted);
    align-self: flex-start;
}

/* ===== Ad Banner ===== */
.ad-banner {
    background: var(--bg);
    border: 1px dashed var(--border);
    border-radius: var(--radius);
    padding: 20px;
    text-align: center;
    margin: 32px 0;
    color: var(--text-muted);
    font-size: 13px;
    min-height: 90px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.ad-sidebar {
    background: var(--bg);
    border: 1px dashed var(--border);
    border-radius: var(--radius);
    padding: 16px;
    text-align: center;
    color: var(--text-muted);
    font-size: 12px;
    min-height: 250px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ===== Tool Page Layout ===== */
.tool-page {
    padding: 32px 0;
}

.tool-page-header {
    text-align: center;
    margin-bottom: 32px;
}

.tool-page-header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.tool-page-header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

.tool-workspace {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 24px;
    align-items: start;
}

.tool-main {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
}

.tool-sidebar {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* ===== Drop Zone ===== */
.drop-zone {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 48px 24px;
    text-align: center;
    transition: all 0.2s;
    cursor: pointer;
}

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

.drop-zone-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.drop-zone h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.drop-zone p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.2s;
}

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

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

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text);
    border: 1px solid var(--border);
}

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

.btn-lg {
    padding: 14px 28px;
    font-size: 16px;
    border-radius: var(--radius);
}

.btn-block {
    width: 100%;
}

/* ===== Settings Panel ===== */
.settings-panel {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px;
}

.settings-panel h3 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text);
}

.setting-group {
    margin-bottom: 16px;
}

.setting-group label {
    display: block;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.setting-group select,
.setting-group input[type="number"],
.setting-group input[type="text"] {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--text);
    background: var(--bg);
}

.setting-group select:focus,
.setting-group input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* ===== File List ===== */
.file-list {
    margin-top: 24px;
}

.file-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    margin-bottom: 8px;
}

.file-item-thumb {
    width: 40px;
    height: 40px;
    border-radius: 6px;
    object-fit: cover;
    background: var(--bg-secondary);
}

.file-item-info {
    flex: 1;
}

.file-item-name {
    font-size: 13px;
    font-weight: 500;
    color: var(--text);
}

.file-item-size {
    font-size: 11px;
    color: var(--text-muted);
}

.file-item-status {
    font-size: 12px;
    font-weight: 500;
}

.file-item-status.done { color: var(--success); }
.file-item-status.processing { color: var(--warning); }

.file-item-remove {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 18px;
    padding: 4px;
}

.file-item-remove:hover {
    color: var(--error);
}

/* ===== Progress Bar ===== */
.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--border-light);
    border-radius: 100px;
    overflow: hidden;
    margin: 8px 0;
}

.progress-bar-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 100px;
    transition: width 0.3s ease;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg);
    border-top: 1px solid var(--border);
    padding: 48px 0 24px;
    margin-top: 64px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: 12px;
    line-height: 1.6;
}

.footer-col h4 {
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.footer-col a {
    display: block;
    font-size: 14px;
    color: var(--text-secondary);
    padding: 4px 0;
    transition: color 0.2s;
}

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

.footer-bottom {
    border-top: 1px solid var(--border-light);
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .header .container {
        height: 56px;
    }

    .nav {
        display: none;
    }

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

    .hero h1 {
        font-size: 1.8rem;
    }

    .hero {
        padding: 40px 20px;
    }

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

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

    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 24px;
    }
}

@media (max-width: 480px) {
    .hero-badges {
        flex-direction: column;
        align-items: center;
    }

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