/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #1a1a2e;
    background: #f8f9fa;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ===== Container ===== */
.container { max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }

/* ===== Breadcrumb ===== */
.breadcrumb {
    background: linear-gradient(135deg, #16213e 0%, #22314e 100%);
    padding: 0.7rem 0;
    font-size: 0.85rem;
    border-bottom: 1px solid rgba(255, 209, 102, 0.18);
}
.breadcrumb a {
    color: #fff2c7;
    text-decoration: none;
    font-weight: 500;
}
.breadcrumb a:hover { color: #ffd166; }
.breadcrumb span { color: #d6dfef; }

/* ===== Highlight Box (Articles) ===== */
.highlight-box {
    background: #fffcf0;
    border-left: 4px solid #ffd166;
    padding: 1rem 1.25rem;
    margin: 1.5rem 0;
    border-radius: 0 8px 8px 0;
}
.highlight-box p { margin: 0; font-size: 0.9rem; color: #555; }

/* ===== Header ===== */
.header {
    background: #1a1a2e;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}
.header .container { display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; }
.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: #fff;
    text-decoration: none;
    letter-spacing: -0.5px;
}
.logo span { color: #ffd166; }
.nav { display: flex; align-items: center; gap: 1.5rem; }
.nav a {
    color: #ccc;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.2s;
}
.nav a:hover, .nav a.active { color: #ffd166; }
.nav-dropdown {
    position: relative;
}
.nav-dropdown summary {
    list-style: none;
    color: #ccc;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: color 0.2s;
}
.nav-dropdown summary::-webkit-details-marker { display: none; }
.nav-dropdown summary::after {
    content: '▾';
    margin-left: 0.4rem;
    font-size: 0.75rem;
}
.nav-dropdown summary:hover,
.nav-dropdown[open] summary,
.nav-dropdown summary.active {
    color: #ffd166;
}
.nav-dropdown-menu {
    position: absolute;
    top: calc(100% + 0.75rem);
    right: 0;
    min-width: 220px;
    background: #10182d;
    border: 1px solid rgba(255, 209, 102, 0.15);
    border-radius: 12px;
    box-shadow: 0 12px 32px rgba(0,0,0,0.24);
    padding: 0.6rem;
    display: grid;
    gap: 0.2rem;
    z-index: 120;
}
.nav-dropdown-menu a {
    display: block;
    padding: 0.55rem 0.75rem;
    border-radius: 8px;
    color: #d6dfef;
}
.nav-dropdown-menu a:hover,
.nav-dropdown-menu a.active {
    background: rgba(255, 209, 102, 0.12);
    color: #ffd166;
}

/* ===== Hero ===== */
.hero {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #fff;
    padding: 4rem 0;
    text-align: center;
}
.hero h1 { font-size: 2.5rem; font-weight: 800; margin-bottom: 1rem; }
.hero p { font-size: 1.15rem; color: #f2f6ff; font-weight: 500; max-width: 650px; margin: 0 auto; line-height: 1.7; }
.hero p br { display: block; }
.article-author-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin: 0 0 1.4rem;
}
.article-author-row-footer {
    margin: 2rem 0 0;
    padding-top: 1rem;
    border-top: 1px solid #e6ebf2;
}
.article-author-avatar {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    flex: 0 0 28px;
    border: 1px solid #d8dfeb;
    background: #eef3f9;
}
.article-author-text {
    min-width: 0;
}
.article-author-name,
.article-author-bio {
    margin: 0;
}
.article-author-name {
    color: #1f2937;
    font-size: 0.82rem;
    font-weight: 700;
    line-height: 1.2;
}
.article-author-bio {
    margin-top: 0;
    color: #6b7280;
    font-size: 0.74rem;
    line-height: 1.3;
}

.intro-section,
.audience-section,
.method-section,
.seo-note-section,
.blog-preview-section,
.cta-section {
    padding: 3rem 0;
}
.intro-shell {
    max-width: 900px;
    margin: 0 auto;
}
.intro-shell h2 {
    font-size: 1.75rem;
    margin-bottom: 1rem;
    color: #1a1a2e;
    text-align: center;
}
.intro-shell > p {
    font-size: 1rem;
    line-height: 1.8;
    color: #4d5875;
    text-align: center;
}

/* ===== Tools Grid ===== */
.tools-grid-section { padding: 3rem 0; }
.tools-grid-section h2 { text-align: center; font-size: 1.75rem; margin-bottom: 2rem; color: #1a1a2e; }
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}
.tool-card {
    background: #fff;
    border-radius: 12px;
    padding: 1.75rem;
    text-decoration: none;
    color: inherit;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    transition: transform 0.2s, box-shadow 0.2s;
    position: relative;
    border: 1px solid #eee;
}
.tool-card:hover:not(.disabled) { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(0,0,0,0.1); }
.tool-card.featured { border-color: #ffd166; background: #fffcf0; }
.tool-card.disabled { opacity: 0.6; cursor: default; }
.tool-icon { font-size: 2rem; margin-bottom: 0.75rem; line-height: 1; }
.tool-card h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 0.5rem; }
.tool-card p { font-size: 0.9rem; color: #666; line-height: 1.5; }
.tool-tag {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: #ffd166;
    color: #1a1a2e;
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
}

.audience-section {
    background: #fff;
    border-top: 1px solid #eef1f6;
    border-bottom: 1px solid #eef1f6;
}
.audience-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}
.audience-card {
    background: #ffffff;
    border: 1px solid #e8edf5;
    border-radius: 14px;
    padding: 1.35rem 1.5rem;
    box-shadow: 0 8px 24px rgba(16, 24, 45, 0.04);
}
.audience-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
    color: #1a1a2e;
}
.audience-card p {
    font-size: 0.95rem;
    line-height: 1.7;
    color: #55617d;
    max-width: 28ch;
}

/* ===== Benefits ===== */
.about-section { padding: 3rem 0; background: #fff; }
.about-section h2 { text-align: center; font-size: 1.75rem; margin-bottom: 2rem; }
.benefits { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 2rem; }
.benefit h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 0.5rem; color: #1a1a2e; }
.benefit p { font-size: 0.95rem; color: #555; line-height: 1.6; }
.method-section {
    background: #fff;
    border-top: 1px solid #eef1f6;
}
.method-section .intro-shell {
    max-width: 820px;
}

.blog-preview-section {
    background: linear-gradient(180deg, #f8f9fa 0%, #f1f5fb 100%);
}
.blog-preview-section a {
    color: #1a1a2e;
    font-weight: 700;
}

.cta-section {
    background: #1a1a2e;
}
.cta-section .intro-shell h2 {
    color: #fff;
}
.cta-section .intro-shell > p {
    color: #d8e1f2;
}

/* ===== Footer ===== */
.footer {
    margin-top: auto;
    background: #1a1a2e;
    color: #888;
    padding: 1.5rem 0;
    text-align: center;
    font-size: 0.85rem;
}
.footer-note {
    max-width: 860px;
    margin: 0 auto 1rem;
    font-size: 0.92rem;
    line-height: 1.8;
    color: #c2ccdf;
}
.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    flex-wrap: wrap;
    margin-bottom: 0.75rem;
}
.footer-links a {
    color: #d6dfef;
    text-decoration: none;
}
.footer-links a:hover { color: #ffd166; }

.page-section {
    padding: 3rem 0;
    background: #fff;
}
.page-shell {
    max-width: 820px;
    margin: 0 auto;
}
.page-shell h2 {
    font-size: 1.5rem;
    margin: 2rem 0 0.75rem;
    color: #1a1a2e;
}
.page-shell h2:first-child { margin-top: 0; }
.page-shell p,
.page-shell li {
    font-size: 0.96rem;
    color: #555;
    line-height: 1.75;
}
.page-shell p { margin-bottom: 1rem; }
.page-shell ul {
    margin: 0 0 1rem 1.25rem;
}
.contact-card {
    background: #fffcf0;
    border: 1px solid #f1df9c;
    border-radius: 12px;
    padding: 1.25rem;
    margin: 1.5rem 0;
}
.contact-card a {
    color: #1a1a2e;
    font-weight: 700;
}

/* ===== Calculator Page ===== */
.calc-hero {
    background: linear-gradient(135deg, #1a1a2e 0%, #243b55 100%);
    color: #fff;
    padding: 2.5rem 0;
    text-align: center;
}
.calc-hero h1 { font-size: 2rem; font-weight: 800; margin-bottom: 0.5rem; }
.calc-hero p { color: #b0b8d1; font-size: 1rem; }

.calc-section { padding: 2.5rem 0; }
.calc-wrapper {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
    justify-content: center;
    align-items: flex-start;
}
.calc-form,
.calc-results {
    flex: 1 1 360px;
    max-width: 520px;
}
@media (max-width: 768px) {
    .calc-wrapper { display: grid; grid-template-columns: 1fr; }
    .calc-form,
    .calc-results { max-width: none; }
}

/* ===== Calculator Form ===== */
.calc-form {
    background: #fff;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    border: 1px solid #eee;
}
.calc-form h2 { font-size: 1.3rem; margin-bottom: 1.25rem; color: #1a1a2e; }
.form-group { margin-bottom: 1.25rem; }
.form-group label {
    display: block;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 0.4rem;
    color: #333;
}
.form-group input, .form-group select {
    width: 100%;
    padding: 0.7rem 0.9rem;
    border: 1.5px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.2s;
    background: #fafafa;
}
.form-group input:focus, .form-group select:focus {
    outline: none;
    border-color: #ffd166;
    background: #fff;
}
.form-group .unit-hint { font-size: 0.8rem; color: #888; margin-top: 0.2rem; }
.calc-btn {
    width: 100%;
    padding: 0.85rem;
    background: #ffd166;
    color: #1a1a2e;
    border: none;
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 700;
    cursor: pointer;
    transition: background 0.2s;
}
.calc-btn:hover { background: #f0c04d; }
.reset-btn {
    width: 100%;
    padding: 0.6rem;
    margin-top: 0.6rem;
    background: transparent;
    color: #888;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s;
}
.reset-btn:hover { background: #f5f5f5; color: #333; }

/* ===== Results ===== */
.calc-results {
    background: #fff;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    border: 1px solid #eee;
}
.calc-results h2 { font-size: 1.3rem; margin-bottom: 1.25rem; color: #1a1a2e; }
.result-grid { display: grid; gap: 1rem; }
.result-item {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 1rem 1.25rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.result-item .label { font-size: 0.9rem; color: #555; font-weight: 500; }
.result-item .value { font-size: 1.2rem; font-weight: 700; color: #1a1a2e; }
.result-item.highlight { background: #fffcf0; border: 1px solid #ffd166; }
.result-item.highlight .value { color: #1a1a2e; font-size: 1.4rem; }
.result-note { font-size: 0.85rem; color: #888; margin-top: 1rem; line-height: 1.5; }

/* ===== SEO Content ===== */
.content-section { padding: 3rem 0; background: #fff; }
.content-section h2 { font-size: 1.5rem; margin-bottom: 1rem; color: #1a1a2e; }
.content-section h3 { font-size: 1.15rem; margin: 1.5rem 0 0.75rem; color: #333; }
.content-section p { font-size: 0.95rem; color: #555; line-height: 1.7; margin-bottom: 1rem; }
.content-section ul,
.content-section ol {
    margin: 0 0 1rem 1.5rem;
    padding-left: 1.25rem;
}
.content-section ol {
    list-style-position: outside;
}
.content-section li {
    font-size: 0.95rem;
    color: #555;
    line-height: 1.7;
    margin-bottom: 0.3rem;
    padding-left: 0.2rem;
}
.content-section > .container { max-width: 980px; }

.faq-item {
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #eee;
}
.faq-item:last-child { border-bottom: none; }
.faq-item h3 { font-size: 1.05rem; margin: 0 0 0.4rem 0; color: #1a1a2e; cursor: pointer; }
.faq-item p { font-size: 0.92rem; color: #555; }
.disclaimer {
    margin-top: 1.75rem;
    padding: 1rem 1.2rem;
    background: #fffcf0;
    border: 1px solid #f1df9c;
    border-radius: 10px;
    font-size: 0.9rem;
    line-height: 1.7;
    color: #5f5640;
}

/* ===== Comparison Table ===== */
.comparison-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    font-size: 0.9rem;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 1px 6px rgba(0,0,0,0.06);
}
.comparison-table thead {
    background: #1a1a2e;
    color: #fff;
}
.comparison-table th {
    padding: 0.75rem 0.8rem;
    text-align: left;
    font-weight: 600;
    font-size: 0.85rem;
    white-space: nowrap;
}
.comparison-table td {
    padding: 0.7rem 0.8rem;
    border-bottom: 1px solid #eee;
    color: #444;
}
.comparison-table tbody tr:hover {
    background: #f8f9fa;
}
.comparison-table tbody tr:last-child td {
    border-bottom: none;
}
@media (max-width: 768px) {
    .comparison-table { font-size: 0.8rem; }
    .comparison-table th,
    .comparison-table td { padding: 0.5rem 0.4rem; }
    .comparison-table th { white-space: normal; }
}

/* ===== Responsive ===== */
@media (max-width: 600px) {
    .hero h1 { font-size: 1.75rem; }
    .hero { padding: 2.5rem 0; }
    .article-author-row {
        gap: 0.65rem;
        margin-bottom: 1.2rem;
    }
    .article-author-avatar {
        width: 22px;
        height: 22px;
        flex-basis: 22px;
    }
    .tools-grid { grid-template-columns: 1fr; }
    .header .container { flex-direction: column; gap: 0.75rem; }
    .nav { flex-wrap: wrap; justify-content: center; }
    .nav-dropdown-menu {
        position: static;
        margin-top: 0.6rem;
        min-width: 100%;
    }
}