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

:root {
    --primary: #4F46E5;
    --primary-hover: #4338CA;
    --primary-light: #EEF2FF;
    --success: #10B981;
    --success-light: #D1FAE5;
    --danger: #EF4444;
    --warning: #F59E0B;
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-500: #6B7280;
    --gray-700: #374151;
    --gray-900: #111827;
    --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 -1px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
    --max-width: 960px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--gray-900);
    background: var(--gray-50);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

/* Header */
header {
    background: #fff;
    border-bottom: 1px solid var(--gray-200);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 0;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 6px;
}

.logo .dot {
    color: var(--success);
}

.nav-links {
    display: flex;
    gap: 20px;
    align-items: center;
}

.nav-links a {
    color: var(--gray-700);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
}

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

.nav-links .nav-tools {
    color: var(--primary);
    font-weight: 600;
}

/* Mobile menu */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    color: var(--gray-700);
}

.menu-toggle svg {
    width: 24px;
    height: 24px;
}

/* Ad Containers */
.ad-container {
    max-width: 728px;
    margin: 16px auto;
    min-height: 90px;
    background: var(--gray-100);
    border: 1px dashed var(--gray-300);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-500);
    font-size: 0.8rem;
    border-radius: var(--radius);
}

.ad-top { min-height: 90px; }
.ad-mid { min-height: 250px; }
.ad-bottom { min-height: 90px; }

/* Hero (shared for tool pages) */
.hero {
    padding: 40px 0 24px;
    text-align: center;
}

.hero h1 {
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 10px;
    color: var(--gray-900);
}

.subtitle {
    font-size: 1.05rem;
    color: var(--gray-500);
    margin-bottom: 28px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Upload Zone (shared for file tools) */
.upload-zone {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius);
    padding: 48px 24px;
    cursor: pointer;
    transition: all 0.2s;
    background: #fff;
}

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

.upload-zone.processing {
    pointer-events: none;
    opacity: 0.7;
}

.upload-icon {
    color: var(--primary);
    margin-bottom: 12px;
}

.upload-text {
    font-size: 1.1rem;
    color: var(--gray-700);
    margin-bottom: 8px;
}

.upload-link {
    color: var(--primary);
    font-weight: 600;
    text-decoration: underline;
}

.upload-hint {
    font-size: 0.85rem;
    color: var(--gray-500);
}

/* Settings panels */
.settings {
    display: flex;
    gap: 24px;
    margin-top: 24px;
    flex-wrap: wrap;
    justify-content: center;
    align-items: flex-end;
}

.setting-group {
    background: #fff;
    padding: 16px 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    flex: 1;
    min-width: 200px;
    max-width: 280px;
}

.setting-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 8px;
}

.setting-group input[type="range"] {
    width: 100%;
    accent-color: var(--primary);
}

.range-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--gray-500);
    margin-top: 4px;
}

.setting-group input[type="number"],
.setting-group input[type="text"],
.setting-group textarea,
.setting-group select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    color: var(--gray-700);
    font-family: inherit;
}

.setting-group textarea {
    resize: vertical;
    min-height: 120px;
}

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

/* Results */
.results {
    margin-top: 32px;
    text-align: left;
}

.results-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
    flex-wrap: wrap;
    gap: 12px;
}

.results-header h2 {
    font-size: 1.3rem;
    font-weight: 700;
}

.results-actions {
    display: flex;
    gap: 8px;
}

.results-summary {
    background: var(--primary-light);
    border: 1px solid #C7D2FE;
    border-radius: var(--radius);
    padding: 16px 20px;
    margin-bottom: 16px;
    font-size: 0.95rem;
    color: var(--primary-hover);
    font-weight: 500;
}

.results-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.result-item {
    background: #fff;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 16px 20px;
    display: flex;
    align-items: center;
    gap: 16px;
    box-shadow: var(--shadow);
}

.result-thumb {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-sm);
    object-fit: cover;
    border: 1px solid var(--gray-200);
    flex-shrink: 0;
}

.result-info {
    flex: 1;
    min-width: 0;
}

.result-name {
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.result-size {
    font-size: 0.8rem;
    color: var(--gray-500);
}

.result-size .arrow {
    margin: 0 6px;
    color: var(--gray-300);
}

.result-savings {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--success);
}

.result-download {
    flex-shrink: 0;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

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

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

.btn-secondary {
    background: var(--primary-light);
    color: var(--primary);
    border: 1px solid #C7D2FE;
}

.btn-secondary:hover {
    background: #E0E7FF;
}

.btn-ghost {
    background: transparent;
    color: var(--gray-500);
    border: 1px solid var(--gray-300);
}

.btn-ghost:hover {
    background: var(--gray-100);
    color: var(--gray-700);
}

.btn-danger {
    background: #FEF2F2;
    color: var(--danger);
    border: 1px solid #FECACA;
}

.btn-danger:hover {
    background: #FEE2E2;
}

.btn-sm {
    padding: 6px 14px;
    font-size: 0.8rem;
}

/* Progress bar */
.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--gray-200);
    border-radius: 3px;
    margin-top: 8px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 3px;
    transition: width 0.3s;
}

/* Tool page content sections */
.content-section {
    padding: 64px 0;
}

.content-section h2 {
    text-align: center;
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 40px;
}

/* How It Works */
.how-it-works .steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.step {
    text-align: center;
}

.step-number {
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 700;
    margin: 0 auto 16px;
}

.step h3 {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.step p {
    font-size: 0.9rem;
    color: var(--gray-500);
}

/* Features */
.features {
    background: #fff;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature {
    text-align: center;
    padding: 24px;
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 12px;
}

.feature h3 {
    font-size: 1.05rem;
    margin-bottom: 8px;
}

.feature p {
    font-size: 0.85rem;
    color: var(--gray-500);
}

/* FAQ */
.faq-list {
    max-width: 720px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    margin-bottom: 8px;
    overflow: hidden;
}

.faq-item summary {
    padding: 16px 20px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.faq-item summary::after {
    content: '+';
    font-size: 1.25rem;
    color: var(--gray-500);
    transition: transform 0.2s;
}

.faq-item[open] summary::after {
    content: '\2212';
}

.faq-item p {
    padding: 0 20px 16px;
    font-size: 0.9rem;
    color: var(--gray-500);
    line-height: 1.7;
}

/* Homepage tool grid */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.tool-card {
    background: #fff;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 28px 24px;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
}

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

.tool-card-icon {
    font-size: 2rem;
    margin-bottom: 12px;
}

.tool-card h3 {
    font-size: 1.05rem;
    margin-bottom: 6px;
    color: var(--gray-900);
}

.tool-card p {
    font-size: 0.85rem;
    color: var(--gray-500);
    flex: 1;
}

.tool-card .tool-tag {
    display: inline-block;
    margin-top: 12px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 3px 8px;
    border-radius: 4px;
    background: var(--primary-light);
    color: var(--primary);
}

.tool-card .tool-tag.dev {
    background: #FEF3C7;
    color: #92400E;
}

.tool-card .tool-tag.pdf {
    background: #FCE7F3;
    color: #9D174D;
}

.tool-card .tool-tag.image {
    background: var(--primary-light);
    color: var(--primary);
}

.tool-card .tool-tag.text {
    background: #D1FAE5;
    color: #065F46;
}

.tool-card .tool-tag.security {
    background: #FEE2E2;
    color: #991B1B;
}

/* Breadcrumb */
.breadcrumb {
    font-size: 0.85rem;
    color: var(--gray-500);
    margin-bottom: 8px;
}

.breadcrumb a {
    color: var(--primary);
    text-decoration: none;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

/* Footer */
footer {
    background: var(--gray-900);
    color: var(--gray-500);
    padding: 40px 0 24px;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 40px;
    margin-bottom: 24px;
    flex-wrap: wrap;
}

.footer-brand .logo {
    display: inline-block;
    margin-bottom: 8px;
    color: #fff;
}

.footer-brand p {
    font-size: 0.85rem;
    max-width: 300px;
}

.footer-links h4 {
    color: #fff;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 12px;
}

.footer-links a {
    display: block;
    color: var(--gray-500);
    text-decoration: none;
    font-size: 0.85rem;
    margin-bottom: 6px;
}

.footer-links a:hover {
    color: #fff;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 16px;
    text-align: center;
    font-size: 0.8rem;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 1.75rem;
    }

    .subtitle {
        font-size: 0.95rem;
    }

    .upload-zone {
        padding: 32px 16px;
    }

    .settings {
        flex-direction: column;
        align-items: center;
    }

    .setting-group {
        max-width: 100%;
    }

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

    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }

    .tools-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    .result-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .result-thumb {
        width: 100%;
        height: 120px;
        object-fit: cover;
    }

    .results-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .ad-container {
        margin: 12px 20px;
    }

    .nav-links {
        display: none;
    }

    .menu-toggle {
        display: block;
    }

    .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: #fff;
        padding: 16px 20px;
        border-bottom: 1px solid var(--gray-200);
        box-shadow: var(--shadow-md);
    }

    .footer-content {
        flex-direction: column;
        gap: 24px;
    }
}

@media (max-width: 480px) {
    .feature-grid,
    .tools-grid {
        grid-template-columns: 1fr;
    }

    .hero h1 {
        font-size: 1.5rem;
    }
}