/* === Color Variables and Dark Mode === */
:root {
    --bg-color: #ffffff;
    --text-color: #333333;
    --nav-bg: #f0f0f0;
    --nav-text: #333333;
    --nav-hover: #007bff;
    --nav-active-bg: rgba(0, 123, 255, 0.1);
    --link-color: #007bff;
    --border-color: rgba(0, 0, 0, 0.08);
    --caption-color: #555555;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #2a2a2a;
        --text-color: #e0e0e0;
        --nav-bg: #3a3a3a;
        --nav-text: #e0e0e0;
        --nav-hover: #66b3ff;
        --nav-active-bg: rgba(102, 179, 255, 0.2);
        --link-color: #66b3ff;
        --border-color: rgba(255, 255, 255, 0.1);
        --caption-color: #b0b0b0;
    }
}

/* Manual light mode override */
body:not(.dark-mode) {
    --bg-color: #ffffff;
    --text-color: #333333;
    --nav-bg: #f0f0f0;
    --nav-text: #333333;
    --nav-hover: #007bff;
    --nav-active-bg: rgba(0, 123, 255, 0.1);
    --link-color: #007bff;
    --border-color: rgba(0, 0, 0, 0.08);
    --caption-color: #555555;
}

/* Manual dark mode override */
body.dark-mode {
    --bg-color: #2a2a2a;
    --text-color: #e0e0e0;
    --nav-bg: #3a3a3a;
    --nav-text: #e0e0e0;
    --nav-hover: #66b3ff;
    --nav-active-bg: rgba(102, 179, 255, 0.2);
    --link-color: #66b3ff;
    --border-color: rgba(255, 255, 255, 0.1);
    --caption-color: #b0b0b0;
}

/* === Base Layout === */
body {
    margin: 0;
    font-family: sans-serif;
    display: flex;
    flex-direction: column;
    height: 100vh;
    height: 100dvh;
    /* Dynamic viewport height for mobile browsers */
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow: hidden;
}

main {
    flex: 1;
    padding: 1rem;
    padding-bottom: calc(2.1rem + env(safe-area-inset-bottom));
    overflow-y: auto;
    width: 100%;
    box-sizing: border-box;
    min-width: 200px;
}

/* Ensure proper spacing for desktop */
@media (min-width: 769px) {
    main {
        padding-bottom: calc(3rem + env(safe-area-inset-bottom));
    }
}

.content-container {
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
}

html {
    scroll-behavior: smooth;
}

a {
    color: var(--link-color);
}

/* === Navigation === */
.main-nav {
    background-color: var(--nav-bg);
    min-width: 200px;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.2rem;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    height: 50px;
    padding: 0.1rem;
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: stretch;
    flex: 1;
    width: 100%;
    max-width: 800px;
    height: 100%;
    margin: 0 auto;
}

.main-nav li {
    margin: 0;
    flex: 1;
    text-align: center;
    min-width: 0;
    display: flex;
    align-items: stretch;
    height: 100%;
}

.main-nav li:nth-child(1),
.main-nav li:nth-child(2) {
    flex: 0.95;
}

.main-nav li:nth-child(3) {
    flex: 1.2;
}

.main-nav li:nth-child(4) {
    flex: 1.45;
}

.main-nav a {
    text-decoration: none;
    color: var(--nav-text);
    font-weight: 500;
    padding: 0.1rem 0.3rem;
    border-radius: 4px;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    box-sizing: border-box;
    white-space: normal;
    word-wrap: break-word;
    line-height: 1.2;
    text-align: center;
}

.main-nav a:hover {
    background-color: var(--nav-hover);
    color: white;
}

.main-nav a.active {
    background-color: var(--nav-active-bg);
    color: var(--nav-hover);
}

/* === Typography & Spacing === */
h1 {
    margin-top: 0.7rem;
    margin-bottom: 0.3rem;
}

h2 {
    padding-top: 0.7rem;
    margin-top: 0.2rem;
    margin-bottom: 0.3rem;
}

p {
    margin-bottom: 0.75rem;
    line-height: 1.5;
}

li {
    margin-bottom: 0.4rem;
}

section {
    margin-bottom: 1.5rem;
}

/* === Flex Layout for Side-by-Side Content === */
.flex-row {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
    margin-bottom: 1.5rem;
    flex-wrap: nowrap;
    flex-direction: column;
}

.logo-row {
    display: flex;
    justify-content: space-around;
    align-items: stretch;
    flex-direction: row;
    gap: 1rem;
    flex: 1;
    max-width: none;
}

.logo-image-container {
    padding: 1px;
    max-width: 300px;
    flex: 1;
}

.logo-image {
    width: auto;
    height: auto;
    min-width: 100px;
    min-height: 100px;
    max-width: 300px;
    max-height: 300px;
}

.flex-row .image-container img {
    width: 100%;
    height: auto;
}

.img-caption,
.img-caption-default {
    display: block;
    margin-top: 0.25rem;
    text-align: center;
    color: var(--caption-color);
    font-size: 22px;
}

.img-caption-default {
    font-size: 18px;
}

.img-container {
    max-width: 800px;
    padding: 4px;
    height: auto;
    display: block;
}

.img-header {
    margin-left: -4px;
    margin-right: -4px;
    padding-bottom: -0.3rem;
    height: auto;
    width: 100%;
}

img {
    max-width: 100%;
    height: auto;
}

/* === Navigation Buttons Container === */
.nav-buttons {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    position: absolute;
    bottom: 100%;
    gap: 0.2rem;
    right: calc(0.5rem + env(safe-area-inset-right));
    margin-bottom: 0.2rem;
}

/* === Language Toggle Button === */
.language-toggle {
    background: none;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    line-height: 1;
    text-align: center;
    width: 36px;
    height: 36px;
    flex-shrink: 0;
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.language-toggle:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    border-color: var(--nav-hover);
}

.language-toggle:focus {
    outline: none;
    box-shadow: 0 0 0 3px var(--link-color);
}

/* === Dark Mode Toggle Button === */
.dark-mode-toggle {
    background: none;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    line-height: 1;
    text-align: center;
    width: 36px;
    height: 36px;
    flex-shrink: 0;
}

.dark-mode-toggle:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.dark-mode-toggle:focus {
    outline: none;
    box-shadow: 0 0 0 3px var(--link-color);
}

body {
    font-size: 18px;
}

@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    h2 {
        padding-top: 0.7rem;
        font-size: 18px;
    }

    .img-caption {
        font-size: 19px;
    }

    .img-caption-default {
        font-size: 16px;
    }

    .language-toggle {
        width: 42px;
        height: 42px;
        font-size: 0.85rem;
    }

    .dark-mode-toggle {
        width: 42px;
        height: 42px;
        font-size: 1.1rem;
    }

    .main-nav {
        padding: 0.1rem;
        padding-bottom: calc(0.1rem + max(env(safe-area-inset-bottom), 10px));
        height: 40px;
    }

    main {
        padding-bottom: calc(4.0rem + max(env(safe-area-inset-bottom), 10px));
    }
}

@media (max-width: 400px) {
    .img-caption {
        font-size: 18px;
    }

    .img-caption-default {
        font-size: 15px;
    }

    .main-nav a {
        font-size: 0.85rem;
        padding: 0.1rem 0.2rem;
    }

    main {
        padding-bottom: calc(4.0rem + max(env(safe-area-inset-bottom), 10px));
    }
}

/* Narrow screens like Samsung Galaxy S8 (360px width) */
@media (max-width: 360px) {
    h2 {
        font-size: 15px;
    }

    body {
        font-size: 15px;
    }

    .img-caption {
        font-size: 18px;
    }

    .main-nav a {
        font-size: 0.7rem;
        padding: 0.1rem 0.2rem;
    }

    .language-toggle {
        width: 40px;
        height: 40px;
        font-size: 0.8rem;
    }

    .dark-mode-toggle {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }

    main {
        padding-bottom: calc(4.0rem + max(env(safe-area-inset-bottom), 10px));
    }
}