:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #f472b6;
    --accent: #34d399;
    --bg: #ffffff;
    --bg-card: #f8fafc;
    --bg-hover: #f1f5f9;
    --text: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border: #e2e8f0;
    --border-focus: #6366f1;
    --success: #10b981;
    --error: #ef4444;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px 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);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --bg: #0f172a;
    --bg-card: #1e293b;
    --bg-hover: #334155;
    --text: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --border: #334155;
    --border-focus: #818cf8;
    --error: #f87171;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: var(--transition);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: rgba(255, 255, 255, 0.8);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

[data-theme="dark"] .header {
    background-color: rgba(15, 23, 42, 0.9);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
}

.logo-icon {
    width: 28px;
    height: 28px;
    color: var(--primary);
}

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

.nav-link {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    font-size: 0.875rem;
}

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

.nav-link.active {
    color: var(--primary);
    background-color: rgba(99, 102, 241, 0.1);
}

.mobile-menu-btn {
    display: none;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-sm);
    background-color: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    transition: var(--transition);
}

.mobile-menu-btn:hover {
    background-color: var(--bg-hover);
    color: var(--text);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background-color: currentColor;
    border-radius: 1px;
    transition: all 0.3s ease;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

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

.theme-toggle {
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-sm);
    background-color: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.theme-toggle:hover {
    background-color: var(--bg-hover);
    color: var(--text);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    position: absolute;
    transition: opacity 0.2s;
}

.sun-icon {
    opacity: 1;
}

[data-theme="dark"] .sun-icon {
    opacity: 0;
}

.moon-icon {
    opacity: 0;
}

[data-theme="dark"] .moon-icon {
    opacity: 1;
}

.hero {
    min-height: 25vh;
    max-height: 280px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 32px 24px;
    text-align: center;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -25%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -20%;
    width: 80%;
    height: 80%;
    background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 60%);
    pointer-events: none;
}

.hero .container {
    position: relative;
    z-index: 1;
    max-width: 800px;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 700;
    line-height: 1.15;
    margin-bottom: 20px;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: clamp(1rem, 2.5vw, 1.375rem);
    font-weight: 400;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

.section {
    padding: 16px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.section-description {
    font-size: 1rem;
    color: var(--text-secondary);
}

.tool-intro {
    max-width: 700px;
    margin: 0 auto 32px;
}

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

.guide-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.guide-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    font-size: 0.875rem;
    font-weight: 600;
    flex-shrink: 0;
}

.guide-item h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--text-primary);
}

.guide-item p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.card {
    background-color: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: var(--transition);
    width: 100%;
    max-width: 912px;
}

.card:hover {
    box-shadow: var(--shadow-lg);
}

.calculator {
    max-width: 480px;
    margin: 0 auto;
}

.input-group {
    margin-bottom: 24px;
}

.input-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.input-wrapper {
    display: flex;
    align-items: center;
    background-color: var(--bg);
    border: 2px solid var(--border);
    border-radius: var(--radius);
    padding: 4px;
    transition: var(--transition);
}

.input-wrapper:focus-within {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.input-prefix,
.input-suffix {
    padding: 12px 16px;
    color: var(--text-muted);
    font-weight: 500;
}

.input {
    flex: 1;
    padding: 12px 16px;
    background-color: transparent;
    border: none;
    outline: none;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text);
}

.input::placeholder {
    color: var(--text-muted);
}

.tip-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    margin-bottom: 16px;
}

.tip-btn {
    padding: 12px 8px;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    background-color: var(--bg);
    color: var(--text);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: var(--transition);
}

.tip-btn:hover {
    border-color: var(--primary);
    background-color: rgba(99, 102, 241, 0.05);
}

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

.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background-color: var(--border);
    appearance: none;
    cursor: pointer;
    margin-bottom: 8px;
}

.slider::-webkit-slider-thumb {
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--primary);
    cursor: pointer;
    transition: var(--transition);
}

.slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.slider-value {
    display: block;
    text-align: right;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--primary);
}

.results {
    background-color: var(--bg);
    border-radius: var(--radius);
    padding: 24px;
    margin-top: 8px;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.result-item:last-child {
    border-bottom: none;
}

.result-item.total {
    padding-top: 16px;
    margin-top: 8px;
    border-top: 2px solid var(--primary);
}

.result-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.result-value {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
}

.result-item.total .result-value {
    font-size: 1.5rem;
    color: var(--primary);
}

.result-item.highlight {
    background-color: rgba(99, 102, 241, 0.08);
    border-radius: var(--radius-sm);
    margin: 0 -12px;
    padding: 12px;
}

.result-item.highlight .result-value {
    font-size: 1.5rem;
    color: var(--primary);
}

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

.json-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.control-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 10px 16px;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    background-color: var(--bg);
    color: var(--text);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: var(--transition);
}

.control-btn:hover {
    border-color: var(--primary);
    background-color: rgba(99, 102, 241, 0.05);
}

.control-btn svg {
    width: 16px;
    height: 16px;
}

.json-panels {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    min-height: 450px;
}

.json-panel {
    display: flex;
    flex-direction: column;
    gap: 8px;
    min-height: 450px;
}

.panel-label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    flex-shrink: 0;
}

.json-textarea {
    flex: 1;
    min-height: 400px;
    padding: 16px;
    background-color: var(--bg);
    border: 2px solid var(--border);
    border-radius: var(--radius);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    font-size: 0.875rem;
    color: var(--text);
    line-height: 1.6;
    resize: vertical;
    transition: var(--transition);
}

.json-textarea:focus {
    outline: none;
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.json-textarea::placeholder {
    color: var(--text-muted);
}

.json-output {
    flex: 1;
    min-height: 400px;
    padding: 16px;
    background-color: var(--bg);
    border: 2px solid var(--border);
    border-radius: var(--radius);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    font-size: 0.875rem;
    color: var(--text);
    line-height: 1.6;
    overflow: auto;
    white-space: pre-wrap;
    word-break: break-all;
}

.json-output .json-key {
    color: #f472b6;
}

.json-output .json-string {
    color: #34d399;
}

.json-output .json-number {
    color: #60a5fa;
}

.json-output .json-boolean {
    color: #a78bfa;
}

.json-output .json-null {
    color: #94a3b8;
}

.error-message {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    background-color: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: var(--error);
    font-size: 0.875rem;
    display: none;
}

.error-message.show {
    display: block;
}

.footer {
    padding: 32px 0;
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.tools-section {
    padding: 32px 0;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}

.tool-card {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 28px;
    background-color: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    text-decoration: none;
    color: var(--text);
    transition: var(--transition);
}

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

.tool-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
}

.tip-icon {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
}

.json-icon {
    background: linear-gradient(135deg, #34d399 0%, #10b981 100%);
    color: white;
}

.annuity-icon {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
    color: white;
}

.savings-icon {
    background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
    color: white;
}

.tool-icon svg {
    width: 28px;
    height: 28px;
}

.tool-info {
    flex: 1;
}

.tool-name {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 4px;
}

.tool-description {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.tool-arrow {
    color: var(--text-muted);
    transition: var(--transition);
}

.tool-card:hover .tool-arrow {
    color: var(--primary);
    transform: translateX(4px);
}

.tool-arrow svg {
    width: 20px;
    height: 20px;
}

.features-section {
    padding: 48px 0;
    background-color: var(--bg-card);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    min-height: 160px;
}

.feature-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius);
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon svg {
    width: 24px;
    height: 24px;
}

.feature-item h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
}

.feature-item p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.disclaimer-section {
    padding: 32px 0;
    background-color: var(--bg-card);
}

.disclaimer-card {
    background-color: var(--bg);
    border-radius: var(--radius-lg);
    padding: 28px;
    border: 1px solid var(--border);
    max-width: 960px;
    margin: 0 auto;
}

.disclaimer-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 16px;
}

.disclaimer-card p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 12px;
}

.disclaimer-card p:last-child {
    margin-bottom: 0;
}

.disclaimer-important {
    font-weight: 600;
    color: var(--primary);
    background-color: rgba(99, 102, 241, 0.08);
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    margin-top: 16px !important;
}

.formula-box {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin-top: 8px;
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    font-size: 0.8125rem;
    line-height: 1.8;
}

.formula-box p {
    margin-bottom: 6px;
    color: var(--text-secondary);
}

.formula-box p:last-child {
    margin-bottom: 0;
}

.formula-box strong {
    color: var(--primary);
}

.content-card h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
    margin-top: 24px;
    margin-bottom: 12px;
}

.content-card h2:first-child {
    margin-top: 0;
}

.content-card p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
}

.content-card a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
}

.content-card a:hover {
    text-decoration: underline;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin: 24px 0;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 16px;
    background-color: var(--bg-card);
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.contact-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-icon svg {
    width: 24px;
    height: 24px;
}

.contact-item h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 4px;
}

.contact-item p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0 !important;
}

.last-updated {
    font-size: 0.8125rem;
    color: var(--text-muted);
    font-style: italic;
    margin-top: 24px !important;
    padding-top: 16px;
    border-top: 1px solid var(--border);
}

.footer .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    font-size: 0.8125rem;
    color: var(--text-muted);
    text-decoration: none;
    transition: var(--transition);
}

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

.ad-section {
    padding: 16px 0;
    flex-shrink: 0;
    background: linear-gradient(180deg, transparent 0%, rgba(99, 102, 241, 0.03) 50%, transparent 100%);
}

.ad-section .container {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    max-width: 728px;
    margin: 0 auto;
    padding: 0;
}

.ad-unit {
    width: 100%;
    max-width: 728px;
    margin: 0 auto;
    display: flex;
    justify-content: center;
    align-items: center;
    max-height: 300px;
    overflow: hidden;
}

.ad-banner {
    width: 100%;
    max-width: 728px;
    flex-shrink: 0;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: box-shadow 0.3s ease;
}

.ad-banner:hover {
    box-shadow: var(--shadow-lg);
}

.ad-banner .adsbygoogle {
    display: block;
    width: 100%;
}

.ad-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 14px;
    width: 100%;
    max-width: 728px;
    height: 90px;
    max-height: 90px;
    border-radius: var(--radius-lg);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(99, 102, 241, 0.05) 100%);
    border: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    flex-shrink: 0;
    position: relative;
    overflow: hidden;
}

.ad-placeholder::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.1), transparent);
    transition: left 0.6s ease;
}

.ad-placeholder:hover::before {
    left: 100%;
}

.ad-placeholder:hover {
    border-color: var(--primary);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(99, 102, 241, 0.08) 100%);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.1);
    color: var(--text-secondary);
}

.ad-placeholder svg {
    width: 26px;
    height: 26px;
    transition: transform 0.3s ease;
}

.ad-placeholder:hover svg {
    transform: scale(1.1);
}

.ad-label {
    position: absolute;
    top: 6px;
    right: 12px;
    font-size: 0.625rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.main {
    display: flex;
    flex-direction: column;
    min-height: calc(100vh - 64px);
}

.main > section:not(.ad-section):not(.hero) {
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.section .container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.card {
    flex-shrink: 0;
}

.calculator,
.json-tool {
    display: flex;
    flex-direction: column;
    min-height: 0;
}

.json-panels {
    flex: 1;
    min-height: 350px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.json-panel {
    display: flex;
    flex-direction: column;
    min-height: 350px;
}

.json-textarea,
.json-output {
    flex: 1;
    min-height: 300px;
}

@media (max-width: 768px) {
    .tools-grid {
        grid-template-columns: 1fr;
        gap: 16px;
        max-width: 100%;
    }
    
    .tool-card {
        padding: 20px;
        gap: 16px;
    }
    
    .tool-icon {
        width: 48px;
        height: 48px;
    }
    
    .tool-icon svg {
        width: 24px;
        height: 24px;
    }
    
    .tool-name {
        font-size: 1.125rem;
    }
    
    .tool-description {
        font-size: 0.8125rem;
    }
    
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
        max-width: 100%;
    }
    
    .feature-item {
        gap: 8px;
        justify-content: center;
        min-height: 120px;
    }
    
    .feature-icon {
        width: 40px;
        height: 40px;
    }
    
    .feature-icon svg {
        width: 20px;
        height: 20px;
    }
    
    .feature-item h4 {
        font-size: 0.875rem;
    }
    
    .feature-item p {
        font-size: 0.75rem;
    }
    
    .ad-section {
        padding: 12px 0;
    }
    
    .ad-banner {
        max-height: 150px;
    }
    
    .ad-placeholder {
        height: 60px;
        max-height: 60px;
        font-size: 0.75rem;
        gap: 10px;
    }
    
    .ad-placeholder svg {
        width: 18px;
        height: 18px;
    }
    
    .ad-label {
        font-size: 0.5625rem;
        top: 4px;
        right: 8px;
    }
    
    .section {
        padding: 16px 0;
    }
    
    .hero {
        min-height: 22vh;
        max-height: 220px;
        padding: 24px 16px;
    }
    
    .hero-title {
        font-size: clamp(2rem, 5vw, 3rem);
    }
    
    .hero-subtitle {
        font-size: clamp(0.875rem, 2.5vw, 1.125rem);
    }
    
    .section {
        padding: 16px 0;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .card {
        padding: 20px;
    }
    
    .tip-buttons {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .json-panels {
        grid-template-columns: 1fr;
        min-height: 300px;
    }
    
    .json-panel {
        min-height: 300px;
    }
    
    .json-textarea,
    .json-output {
        min-height: 250px;
    }
    
    .json-controls {
        flex-wrap: wrap;
        gap: 8px;
    }
    
    .control-btn {
        flex: 1;
        min-width: calc(33.333% - 5px);
        padding: 10px 12px;
        font-size: 0.8125rem;
    }
    
    .control-btn svg {
        width: 16px;
        height: 16px;
    }
    
    .tip-buttons {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
    }
    
    .tip-btn {
        padding: 12px 8px;
        font-size: 0.875rem;
    }
    
    .input-group {
        margin-bottom: 20px;
    }
    
    .input-wrapper {
        padding: 3px;
    }
    
    .input-prefix,
    .input-suffix {
        padding: 10px 12px;
        font-size: 0.875rem;
    }
    
    .input {
        padding: 10px 12px;
        font-size: 1rem;
    }
    
    .results {
        padding: 16px;
        margin-top: 16px;
    }
    
    .result-item {
        padding: 12px 0;
    }
    
    .result-label {
        font-size: 0.75rem;
    }
    
    .result-value {
        font-size: 1.125rem;
    }
    
    .tool-intro {
        margin-bottom: 24px;
    }
    
    .tool-guide {
        gap: 16px;
    }
    
    .guide-item {
        gap: 12px;
    }
    
    .guide-number {
        width: 32px;
        height: 32px;
        font-size: 0.75rem;
    }
    
    .guide-item h4 {
        font-size: 0.9375rem;
    }
    
    .guide-item p {
        font-size: 0.8125rem;
    }
    
    .nav {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background-color: var(--bg);
        flex-direction: column;
        padding: 16px;
        gap: 8px;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
        transform: translateY(-150%);
        z-index: 100;
        -webkit-backdrop-filter: blur(12px);
        backdrop-filter: blur(12px);
        opacity: 0;
        transition: all 0.3s ease;
    }

    .nav.active {
        transform: translateY(0);
        opacity: 1;
    }

    .nav-link {
        padding: 12px 16px;
        width: 100%;
        text-align: left;
        font-size: 0.9375rem;
    }

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

@media (max-width: 480px) {
    .ad-section {
        padding: 12px 0;
    }
    
    .ad-section .container {
        max-width: 100%;
        padding: 0 16px;
    }
    
    .ad-unit {
        max-width: 100%;
    }
    
    .ad-placeholder {
        height: 50px;
        max-height: 50px;
        font-size: 0.7rem;
        gap: 8px;
    }
    
    .ad-placeholder svg {
        width: 16px;
        height: 16px;
    }
    
    .ad-label {
        font-size: 0.5rem;
        top: 3px;
        right: 6px;
    }
    
    .container {
        padding: 0 16px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
        gap: 16px;
        max-width: 100%;
    }
    
    .feature-item {
        flex-direction: row;
        align-items: center;
        gap: 16px;
        text-align: left;
        padding: 12px 0;
        border-bottom: 1px solid var(--border);
    }
    
    .feature-item:last-child {
        border-bottom: none;
    }
    
    .feature-icon {
        width: 44px;
        height: 44px;
        flex-shrink: 0;
    }
    
    .feature-icon svg {
        width: 22px;
        height: 22px;
    }
    
    .feature-item h4 {
        font-size: 0.9375rem;
        margin-bottom: 2px;
    }
    
    .feature-item p {
        font-size: 0.8125rem;
    }
    
    .hero {
        min-height: 20vh;
        max-height: 180px;
        padding: 20px 16px;
    }
    
    .hero-title {
        font-size: clamp(1.5rem, 5vw, 2.25rem);
    }
    
    .hero-subtitle {
        font-size: clamp(0.8125rem, 2.5vw, 0.9375rem);
    }
    
    .card {
        padding: 16px;
        border-radius: var(--radius);
    }
    
    .section {
        padding: 16px 0;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .control-btn {
        min-width: calc(50% - 4px);
    }
    
    .json-textarea,
    .json-output {
        padding: 12px;
        font-size: 0.75rem;
        min-height: 200px;
    }
    
    .footer {
        padding: 24px 0;
    }
    
    .footer-links {
        gap: 16px;
    }
    
    .footer-links a {
        font-size: 0.75rem;
    }
}