/* ============================================
   CSS Custom Properties
   ============================================ */
:root {
    --color-primary: #880000;
    --color-primary-light: rgba(255, 255, 255, 0.15);
    --color-text: #000;
    --color-text-light: #f9f9f9;
    --color-text-muted: #555;
    --color-bg: #fff;
    --color-link: #1a0dab;
    --color-link-dark: #ffcccc;
    --color-link-dark-hover: #ffeaea;
    --color-border: rgba(255, 255, 255, 0.1);
    --font-body: 'Open Sans', Arial, sans-serif;
    --font-display: 'Caveat', cursive;
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 40px;
    --spacing-2xl: 60px;
    --max-width: 80%;
    --header-height: 64px;
    --transition-speed: 0.2s;
}

/* Dark mode */
[data-theme="dark"] {
    --color-primary: #4a0000;
    --color-text: #e0e0e0;
    --color-text-light: #f0f0f0;
    --color-text-muted: #aaa;
    --color-bg: #1a1a1a;
    --color-link: #6db3f2;
    --color-link-dark: #ffaaaa;
    --color-link-dark-hover: #ffcccc;
    --color-border: rgba(255, 255, 255, 0.15);
}

/* ============================================
   Base Styles
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.75;
    color: var(--color-text);
    background: var(--color-primary);
    transition: background var(--transition-speed), color var(--transition-speed);
}

a {
    color: var(--color-link);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

img {
    max-width: 100%;
    display: block;
}

/* Skip to content link */
.skip-to-content {
    position: absolute;
    top: -100%;
    left: var(--spacing-lg);
    background: var(--color-primary);
    color: var(--color-text-light);
    padding: var(--spacing-xs) var(--spacing-md);
    z-index: 200;
    border-radius: 0 0 4px 4px;
    font-size: 14px;
    transition: top 0.2s;
}

.skip-to-content:focus {
    top: 0;
    text-decoration: none;
}

/* ============================================
   Header
   ============================================ */
.site-header {
    background-color: var(--color-primary);
    color: var(--color-text-light);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background-color var(--transition-speed);
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: var(--header-height);
    flex-wrap: wrap;
}

.site-title {
    font-size: 24px;
    font-weight: 600;
    padding: var(--spacing-sm) 0;
    text-decoration: none;
    color: inherit;
    font-family: var(--font-display);
    letter-spacing: 1px;
}

.site-title:hover {
    text-decoration: none;
    color: inherit;
}

.site-nav {
    display: flex;
    align-items: center;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 0;
    flex-wrap: wrap;
}

.nav-links li a {
    display: block;
    padding: 20px var(--spacing-md);
    color: var(--color-text-light);
    font-size: 14px;
    font-weight: 400;
    text-decoration: none;
    transition: background var(--transition-speed);
}

.nav-links li a:hover,
.nav-links li a.active {
    background: var(--color-primary-light);
    text-decoration: none;
}

.nav-links li a:focus-visible {
    outline: 2px solid var(--color-text-light);
    outline-offset: -2px;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--color-text-light);
    font-size: 24px;
    cursor: pointer;
    padding: var(--spacing-xs);
}

/* Dark mode toggle */
.theme-toggle {
    background: none;
    border: 2px solid rgba(255, 255, 255, 0.3);
    color: var(--color-text-light);
    font-size: 18px;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
    margin-left: var(--spacing-sm);
    transition: border-color var(--transition-speed), background var(--transition-speed);
    line-height: 1;
}

.theme-toggle:hover {
    border-color: rgba(255, 255, 255, 0.6);
    background: rgba(255, 255, 255, 0.1);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--color-text-light);
    outline-offset: 2px;
}

/* ============================================
   Dark Background Content (Home Page)
   ============================================ */
.dark-bg {
    background: var(--color-primary);
    color: var(--color-text-light);
    max-width: 100%;
    padding: var(--spacing-xl) 0 var(--spacing-2xl);
    transition: background var(--transition-speed);
}

.dark-bg .content-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg) var(--spacing-2xl);
}

.dark-bg h1,
.dark-bg h2,
.dark-bg h3 {
    color: var(--color-text-light);
}

.dark-bg a {
    color: var(--color-link-dark);
    text-decoration: underline;
}

.dark-bg a:hover {
    color: var(--color-link-dark-hover);
    opacity: 0.85;
}

.dark-bg ol,
.dark-bg ul {
    color: var(--color-text-light);
}

.page-section {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg) var(--spacing-xl);
}

/* ============================================
   Intro Section (Home Page)
   ============================================ */
.intro-section {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg) 20px;
}

.intro-layout {
    display: flex;
    gap: var(--spacing-xl);
    align-items: flex-start;
}

.intro-text {
    flex: 1;
}

.intro-text p {
    margin-bottom: var(--spacing-xs);
    line-height: 1.7;
}

.intro-photo {
    flex-shrink: 0;
    padding-top: 10px;
}

.intro-photo img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
}

.handwritten {
    font-family: var(--font-display);
    font-size: 42px;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-light);
}

.dark-bg .section {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg) var(--spacing-xl);
}

.skills-line {
    margin-top: 20px;
    font-size: 16px;
    font-weight: 500;
}

/* ============================================
   News Section
   ============================================ */
.news-section {
    padding-top: var(--spacing-xl);
}

.news-title {
    text-align: center;
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 28px;
    color: var(--color-text-light);
}

.news-year {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

.news-section p {
    margin-bottom: 14px;
    line-height: 1.8;
}

/* News year filter */
.news-filter {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.news-filter-btn {
    background: rgba(255, 255, 255, 0.1);
    color: var(--color-text-light);
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 6px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    font-family: var(--font-body);
    transition: background var(--transition-speed), border-color var(--transition-speed);
}

.news-filter-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.5);
}

.news-filter-btn.active {
    background: rgba(255, 255, 255, 0.25);
    border-color: var(--color-text-light);
    font-weight: 600;
}

.news-filter-btn:focus-visible {
    outline: 2px solid var(--color-text-light);
    outline-offset: 2px;
}

.news-year-group {
    transition: opacity 0.3s ease;
}

.news-year-group.hidden {
    display: none;
}

/* ============================================
   Main Content (Other Pages)
   ============================================ */
.content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg) var(--spacing-2xl);
}

.section {
    margin-bottom: var(--spacing-xl);
}

h1 {
    font-size: 28px;
    font-weight: 400;
    color: var(--color-text);
    margin-bottom: 20px;
}

h2 {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: 18px;
    font-weight: 400;
    color: var(--color-text);
    margin-bottom: var(--spacing-sm);
}

p {
    margin-bottom: var(--spacing-sm);
}

ul, ol {
    margin-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

li {
    margin-bottom: 6px;
}

/* Focus visible for all interactive elements */
a:focus-visible {
    outline: 2px solid currentColor;
    outline-offset: 2px;
}

/* ============================================
   Resume Page
   ============================================ */
.resume-section {
    max-width: 100%;
    padding: 0;
}

.resume-embed {
    width: 100%;
    height: 90vh;
    border: none;
    display: block;
}

/* ============================================
   Hobby Page
   ============================================ */
.race-results {
    margin-bottom: var(--spacing-lg);
}

.race-results li {
    margin-bottom: 4px;
}

.personal-records {
    margin-bottom: var(--spacing-lg);
}

.personal-records li {
    margin-bottom: 4px;
}

.hobby-images {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.hobby-images img {
    max-width: 100%;
    border-radius: 2px;
}

/* ============================================
   Project Page
   ============================================ */
.project-list {
    list-style: none;
    margin-left: 0;
}

.project-list li {
    margin-bottom: var(--spacing-sm);
}

.project-list li a {
    font-size: 15px;
}

.project-list li .project-desc {
    color: var(--color-text-muted);
    font-size: 13px;
    margin-top: 2px;
}

/* ============================================
   Link Page
   ============================================ */
.link-section {
    margin-bottom: 32px;
}

.link-section h3 {
    margin-bottom: var(--spacing-sm);
}

.link-list {
    list-style: none;
    margin-left: 0;
}

.link-list li {
    margin-bottom: var(--spacing-xs);
}

.link-list li a {
    font-size: 15px;
}

.link-list li .link-desc {
    color: var(--color-text-muted);
    font-size: 13px;
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
    background: var(--color-primary);
    color: var(--color-text-light);
    text-align: center;
    padding: 20px var(--spacing-lg);
    font-size: 13px;
    transition: background var(--transition-speed);
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 768px) {
    :root {
        --max-width: 92%;
    }

    .nav-toggle {
        display: block;
    }

    .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        background: var(--color-primary);
    }

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

    .nav-links li a {
        padding: var(--spacing-sm) var(--spacing-md);
        border-top: 1px solid var(--color-border);
    }

    .header-inner {
        flex-wrap: wrap;
    }

    .site-nav {
        width: 100%;
        flex-direction: column;
        align-items: flex-end;
    }

    .nav-toggle {
        position: absolute;
        right: var(--spacing-lg);
        top: 18px;
    }

    .theme-toggle {
        position: absolute;
        right: 60px;
        top: 20px;
    }

    .handwritten {
        font-size: 32px;
    }

    .intro-layout {
        flex-direction: column-reverse;
        align-items: center;
        gap: var(--spacing-lg);
    }

    .intro-photo img {
        width: 160px;
        height: 160px;
    }
}