/* Global Resets, Typography, and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette - Modern Earthy */
    --bg-color: #fcfbf8;

    /* Soft cream/off-white */
    --bg-header: rgb(255 255 255 / 85%);

    /* Translucent white for glassmorphism */
    --bg-card: #fff;

    /* Text Colors */
    --text-main: #2d2a26;

    /* Deep charcoal/brown */
    --text-secondary: #5e5b55;

    /* Muted earth tone */
    --text-heading: #1a1917;

    /* Almost black */
    --traffic-hotspot-text-color: #2d2a26;

    /* Accent Colors */
    --accent: #c2794d;

    /* Terracotta/Burnt Orange */
    --accent-hover: #a8653e;
    --accent-light: #f0e6df;

    /* Light accent background */
    --accent-button: #c2794d;
    --accent-button-hover: #a8653e;

    /* Borders & Shadows */
    --border-color: #e6e2dd;
    --border-secondary: #dcd6ce;
    --shadow-sm: 0 2px 4px rgb(45 42 38 / 5%);
    --shadow-md: 0 4px 12px rgb(45 42 38 / 8%);
    --shadow-lg: 0 8px 24px rgb(45 42 38 / 12%);

    /* Typography */
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
    --font-heading: 'Noto Sans TC', 'Inter', sans-serif;

    /* Tool wrapper themes (kept for compatibility) */
    --tool-dark-page-bg: #020617;
    --tool-dark-text: #e2e8f0;
    --tool-dark-paragraph: #cbd5f5;
    --tool-dark-frame-bg: #030712;
    --tool-dark-frame-border: #1f2937;
    --tool-light-page-bg: #f7f5f2;
    --tool-light-text: #0f172a;
    --tool-light-paragraph: #4b5563;
    --tool-light-frame-border: #d4d4d8;
    --airplane-alert-bg: var(--tool-dark-frame-bg);
    --airplane-alert-heading: #f8fafc;
    --airplane-alert-paragraph: #94a3b8;

    /* Tool embed base palettes (kept for compatibility) */
    --tool-embed-idle-rgb: 148, 163, 184;
    --tool-embed-monitor-rgb: 59, 130, 246;
    --tool-embed-monitor-border-rgb: 96, 165, 250;
    --tool-embed-monitor-strong-rgb: 37, 99, 235;
    --tool-embed-warning-rgb: 234, 179, 8;
    --tool-embed-warning-soft-rgb: 250, 204, 21;
    --tool-embed-warning-strong-rgb: 217, 119, 6;
    --tool-embed-critical-rgb: 248, 113, 113;
    --tool-embed-critical-strong-rgb: 220, 38, 38;
    --tool-embed-pass-accent-rgb: 252, 165, 165;
    --tool-embed-card-bg-dark: #ffffff0a;
    --tool-embed-card-border-dark: rgb(255 255 255 / 10%);
    --tool-embed-card-shadow-dark: #0f172a40;
    --tool-embed-pass-divider-dark: rgb(255 255 255 / 8%);
    --tool-embed-pass-meta-dark: #ffffffb8;
    --tool-embed-pill-bg: #6366f133;
    --tool-embed-pill-text: #a5b4fc;
    --tool-embed-alert-text-dark: #e2e8f0d9;
    --tool-embed-alert-idle-bg: rgb(var(--tool-embed-idle-rgb) / 14%);
    --tool-embed-alert-idle-border: rgb(var(--tool-embed-idle-rgb) / 28%);
    --tool-embed-alert-monitor-bg: rgb(var(--tool-embed-monitor-rgb) / 16%);
    --tool-embed-alert-monitor-border: rgb(var(--tool-embed-monitor-border-rgb) / 45%);
    --tool-embed-alert-warning-bg: rgb(var(--tool-embed-warning-rgb) / 22%);
    --tool-embed-alert-warning-border: rgb(var(--tool-embed-warning-rgb) / 50%);
    --tool-embed-alert-warning-shadow: rgb(var(--tool-embed-warning-rgb) / 20%);
    --tool-embed-alert-critical-bg: rgb(var(--tool-embed-critical-rgb) / 25%);
    --tool-embed-alert-critical-border: rgb(var(--tool-embed-critical-rgb) / 60%);
    --tool-embed-alert-critical-shadow: rgb(var(--tool-embed-critical-rgb) / 28%);
    --tool-embed-alert-active-outline: rgb(var(--tool-embed-critical-rgb) / 30%);
    --tool-embed-alert-active-shadow: rgb(var(--tool-embed-critical-rgb) / 35%);
    --tool-embed-pass-primary-border: rgb(var(--tool-embed-monitor-border-rgb) / 40%);
    --tool-embed-pass-primary-bg-start: rgb(var(--tool-embed-monitor-rgb) / 16%);
    --tool-embed-pass-primary-bg-end: rgb(var(--tool-embed-monitor-rgb) / 5%);
    --tool-embed-pass-active-border: rgb(var(--tool-embed-critical-rgb) / 60%);
    --tool-embed-pass-active-bg-start: rgb(var(--tool-embed-critical-rgb) / 18%);
    --tool-embed-pass-active-bg-end: rgb(var(--tool-embed-pass-accent-rgb) / 10%);
    --tool-embed-link: #646cff;
    --tool-embed-link-hover: #535bf2;
    --tool-embed-button-bg: #1a1a1a;
    --tool-embed-button-hover-border: #646cff;
    --tool-embed-card-bg-light: #ffffffe6;
    --tool-embed-card-border-light: #0f172a14;
    --tool-embed-card-text-light: #0f172a;
    --tool-embed-pass-meta-light: #0f172ab3;
    --tool-embed-alert-text-light: #0f172ab8;
    --tool-embed-alert-idle-bg-light: rgb(var(--tool-embed-idle-rgb) / 20%);
    --tool-embed-alert-idle-border-light: rgb(var(--tool-embed-idle-rgb) / 45%);
    --tool-embed-alert-monitor-bg-light: rgb(var(--tool-embed-monitor-rgb) / 18%);
    --tool-embed-alert-monitor-border-light: rgb(var(--tool-embed-monitor-strong-rgb) / 45%);
    --tool-embed-alert-warning-bg-light: rgb(var(--tool-embed-warning-soft-rgb) / 28%);
    --tool-embed-alert-warning-border-light: rgb(var(--tool-embed-warning-strong-rgb) / 50%);
    --tool-embed-alert-warning-shadow-light: rgb(var(--tool-embed-warning-strong-rgb) / 20%);
    --tool-embed-alert-critical-bg-light: rgb(var(--tool-embed-critical-rgb) / 28%);
    --tool-embed-alert-critical-border-light: rgb(var(--tool-embed-critical-strong-rgb) / 55%);
    --tool-embed-alert-critical-shadow-light: rgb(var(--tool-embed-critical-strong-rgb) / 28%);
    --tool-embed-alert-active-outline-light: rgb(var(--tool-embed-critical-strong-rgb) / 25%);
    --tool-embed-alert-active-shadow-light: rgb(var(--tool-embed-critical-strong-rgb) / 32%);
    --tool-embed-button-bg-light: #f9f9f9;
    --tool-embed-link-hover-light: #747bff;
}

/* Layout & Global Styles */
body {
    font-family: var(--font-main);
    line-height: 1.7;
    color: var(--text-main);
    background-color: var(--bg-color);
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-heading);
    color: var(--text-heading);
    font-weight: 700;
    line-height: 1.3;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s ease;
    font-weight: 500;
}

a:hover {
    color: var(--accent-hover);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
    max-width: 1200px;
    margin: 0 auto;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-heading);
    letter-spacing: -0.02em;
}

/* Hidden but accessible headings */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
    border: 0;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2.5rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

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

/* Hero Section */
.hero {
    text-align: center;
    padding: 6rem 1rem;
    background: linear-gradient(135deg, #fdfbf7 0%, #f5efe6 100%);
    border-radius: 24px;
    margin-bottom: 4rem;
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgb(194 121 77 / 3%) 0%, rgb(255 255 255 / 0%) 70%);
    pointer-events: none;
}

.hero h1 {
    font-size: 3rem;
    color: var(--text-heading);
    margin-bottom: 1.5rem;
    letter-spacing: -0.03em;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Section Styling */
section {
    margin-bottom: 5rem;
    animation: fade-in 0.8s ease-out forwards;
    opacity: 0;
}

section:nth-child(1) {
    animation-delay: 0.1s;
}

section:nth-child(2) {
    animation-delay: 0.2s;
}

section:nth-child(3) {
    animation-delay: 0.3s;
}

@keyframes fade-in {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

section h2 {
    font-size: 1.75rem;
    margin-bottom: 2rem;
    position: relative;
    padding-left: 1rem;
    border-left: 4px solid var(--accent);
}

/* Topics Grid */
.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.topic-card {
    display: flex;
    flex-direction: column;
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s cubic-bezier(0.4, 0, 0.2, 1), border-color 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    height: 100%;
}

.topic-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-light);
}

.topic-card h2 {
    font-size: 1.25rem;
    color: var(--text-heading);
    margin-bottom: 0.75rem;
    border: none;
    padding: 0;
}

.topic-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Knowledge Highlight */
.knowledge-highlight {
    background: var(--bg-card);
    padding: 3rem;
    border-radius: 16px;
    text-align: center;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.knowledge-highlight .topic-card {
    max-width: 400px;
    margin: 0 auto;
    box-shadow: none;
    border: 1px solid var(--border-secondary);
}

/* Chart container */
.chart-container {
    position: relative;
    height: 400px;
    width: 100%;
    max-width: 800px;
    margin: auto;
}

/* Article Page Styling */
.article {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
}

.article h1 {
    font-size: 2.5rem;
    margin-bottom: 2rem;
    color: var(--text-heading);
}

.article h2 {
    font-size: 1.75rem;
    margin: 2.5rem 0 1.5rem;
    color: var(--text-heading);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.article p {
    margin: 1.25rem 0;
    color: var(--text-secondary);
    font-size: 1.05rem;
}

/* Tech news cards */
.cards img {
    width: 100%;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    border-radius: 12px;
}

.pre-line-text {
    white-space: pre-line;
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 0;
    margin-top: 6rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive Design */
@media (width <= 768px) {
    .menu-toggle {
        display: block;
    }

    nav {
        flex-direction: column;
        align-items: flex-start;
        padding: 1rem;
    }

    .nav-links {
        display: none;
        flex-direction: column;
        width: 100%;
        gap: 1rem;
        margin-top: 1.5rem;
        padding-top: 1rem;
        border-top: 1px solid var(--border-color);
    }

    nav.nav-open .nav-links {
        display: flex;
    }

    .hero {
        padding: 4rem 1rem;
    }

    .hero h1 {
        font-size: 2.25rem;
    }

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

    .article {
        padding: 1rem 0;
    }
}

@media (width <= 600px) {
    body {
        padding: 0 16px;
    }
}

/* Utilities */
.image-gallery {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    margin: 2rem 0;
}

.image-gallery img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
}

.rates-table {
    width: 100%;
    max-width: 500px;
    margin: 2rem auto;
    border-collapse: separate;
    border-spacing: 0;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
}

.rates-table th,
.rates-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.rates-table th {
    background-color: #f9f7f4;
    font-weight: 600;
    text-align: left;
}

.rates-table td:last-child {
    text-align: right;
    font-variant-numeric: tabular-nums;
    font-weight: 500;
}

.rates-table tr:last-child td {
    border-bottom: none;
}