/* =====================================================================
   Thai Ebook Reader — Eye-Care Design System
   Palette matches the "paper-like" aesthetic: warm cream backgrounds,
   sage green accents, soft ink-brown text — all chosen to minimize
   blue-light glare and eye strain during long reading sessions.
   ===================================================================== */

:root {
	/* --- Reading mode: Light / Paper (default) --- */
	--color-bg: #f2efe6;
	--color-surface: #faf8f2;
	--color-panel: #ece7d9;
	--color-ink: #3a362e;
	--color-ink-soft: #6b6555;
	--color-accent: #6d8a5e;
	--color-accent-dark: #52694a;
	--color-border: #ddd5c2;
	--color-quote-bg: #e5e0d1;

	/* --- Typography --- */
	--font-body: 'Sarabun', 'Noto Sans Thai', 'IBM Plex Sans Thai', system-ui, sans-serif;
	--font-heading: 'Noto Serif Thai', 'Sarabun', serif;

	/* Base reading size, adjustable at runtime via the font-size toolbar (JS sets this var) */
	--reading-scale: 1;
	--font-size-base: calc(18px * var(--reading-scale));
	--font-size-h1: calc(2.1rem * var(--reading-scale));
	--font-size-h2: calc(1.6rem * var(--reading-scale));
	--font-size-h3: calc(1.25rem * var(--reading-scale));

	--content-max-width: 760px; /* narrower measure = easier long-form reading */
	--radius: 12px;
}

/* --- Sepia mode --- */
body.reading-mode-sepia {
	--color-bg: #ece0c8;
	--color-surface: #f5ecd7;
	--color-panel: #e3d5b3;
	--color-ink: #4a3a24;
	--color-ink-soft: #7a6748;
	--color-border: #d8c39c;
	--color-quote-bg: #ddc9a0;
}

/* --- Dark / night mode: still warm, not pure black or blue-white --- */
body.reading-mode-dark {
	--color-bg: #24221d;
	--color-surface: #2c2a23;
	--color-panel: #34312a;
	--color-ink: #e6e0d0;
	--color-ink-soft: #b5ae99;
	--color-accent: #93b481;
	--color-accent-dark: #a9c898;
	--color-border: #45412f;
	--color-quote-bg: #3a372c;
}

body {
	font-size: var(--font-size-base);
	transition: background-color .25s ease, color .25s ease;
}

h1, h2, h3, h4 {
	font-family: var(--font-heading);
	color: var(--color-ink);
	line-height: 1.35;
	font-weight: 700;
}
h1 { font-size: var(--font-size-h1); }
h2 { font-size: var(--font-size-h2); }
h3 { font-size: var(--font-size-h3); }

p { margin: 0 0 1.2em; }

/* =====================================================================
   Header
   ===================================================================== */
.site-header {
	background: var(--color-surface);
	border-bottom: 1px solid var(--color-border);
	position: sticky;
	top: 0;
	z-index: 50;
}
.site-header-inner {
	max-width: 1160px;
	margin: 0 auto;
	padding: 18px 28px;
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 20px;
	flex-wrap: wrap;
}
.site-branding { display: flex; flex-direction: column; }
.site-title {
	font-family: var(--font-heading);
	font-size: 1.5rem;
	margin: 0;
	color: var(--color-ink);
}
.site-title a { color: inherit; text-decoration: none; }
.site-description { font-size: .82rem; color: var(--color-ink-soft); margin-top: 2px; }

.main-navigation ul {
	display: flex;
	gap: 22px;
	list-style: none;
	margin: 0;
	padding: 0;
	flex-wrap: wrap;
}
.main-navigation a {
	color: var(--color-ink);
	font-size: .92rem;
	letter-spacing: .02em;
	text-decoration: none;
	padding-bottom: 3px;
	border-bottom: 2px solid transparent;
}
.main-navigation a:hover,
.main-navigation .current-menu-item > a {
	border-bottom-color: var(--color-accent);
}

.menu-toggle {
	display: none;
	background: none;
	border: 1px solid var(--color-border);
	border-radius: 8px;
	width: 40px;
	height: 40px;
	align-items: center;
	justify-content: center;
	cursor: pointer;
}

/* --- Reading toolbar: font size + mode switch, present on every page --- */
.reading-toolbar {
	display: flex;
	align-items: center;
	gap: 8px;
}
.reading-toolbar button {
	background: var(--color-panel);
	border: 1px solid var(--color-border);
	color: var(--color-ink);
	border-radius: 8px;
	width: 34px;
	height: 34px;
	font-size: 14px;
	cursor: pointer;
	display: inline-flex;
	align-items: center;
	justify-content: center;
	transition: background .15s ease;
}
.reading-toolbar button:hover,
.reading-toolbar button[aria-pressed="true"] {
	background: var(--color-accent);
	color: #fff;
	border-color: var(--color-accent);
}
.reading-toolbar .rt-sep { width: 1px; height: 20px; background: var(--color-border); margin: 0 4px; }

/* =====================================================================
   Layout
   ===================================================================== */
.site-content {
	max-width: 1160px;
	margin: 0 auto;
	padding: 40px 28px 80px;
}
.content-narrow { max-width: var(--content-max-width); margin: 0 auto; }

.torn-divider {
	border: none;
	height: 1px;
	background: var(--color-border);
	margin: 32px 0;
	position: relative;
}

/* Hero (front page) */
.hero-section {
	background: var(--color-surface);
	border-radius: 18px;
	padding: 56px 40px;
	margin-bottom: 48px;
	display: grid;
	grid-template-columns: 1.1fr .9fr;
	gap: 36px;
	align-items: center;
}
.hero-eyebrow {
	text-transform: uppercase;
	letter-spacing: .12em;
	font-size: .78rem;
	color: var(--color-ink-soft);
	margin-bottom: 10px;
}
.hero-section h1 { margin: 0 0 18px; }
.hero-section p { color: var(--color-ink-soft); font-size: 1.02rem; }
.btn {
	display: inline-block;
	background: var(--color-accent);
	color: #fff !important;
	padding: 12px 26px;
	border-radius: 9px;
	font-weight: 600;
	text-decoration: none !important;
	transition: background .15s ease;
}
.btn:hover { background: var(--color-accent-dark); }
.btn-outline {
	background: transparent;
	border: 1px solid var(--color-accent);
	color: var(--color-accent) !important;
}
.hero-media img {
	border-radius: 14px;
	border: 8px solid var(--color-surface);
	box-shadow: 0 18px 40px rgba(0, 0, 0, .12);
}

/* Feature grid */
.feature-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 30px;
	margin: 48px 0;
	text-align: center;
}
.feature-grid .feature-icon {
	width: 52px; height: 52px;
	margin: 0 auto 14px;
	border-radius: 50%;
	background: var(--color-panel);
	display: flex; align-items: center; justify-content: center;
	color: var(--color-accent);
	font-size: 22px;
}
.feature-grid h3 { margin-bottom: 8px; }
.feature-grid p { color: var(--color-ink-soft); font-size: .92rem; }

/* Card / article listing */
.card-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
	gap: 26px;
}
.book-card, .post-card {
	background: var(--color-surface);
	border: 1px solid var(--color-border);
	border-radius: var(--radius);
	overflow: hidden;
	transition: transform .18s ease, box-shadow .18s ease;
}
.book-card:hover, .post-card:hover {
	transform: translateY(-4px);
	box-shadow: 0 14px 30px rgba(0, 0, 0, .1);
}
.book-card img, .post-card img { width: 100%; aspect-ratio: 4/3; object-fit: cover; }
.card-body { padding: 16px 18px 20px; }
.card-body h3 { font-size: 1.05rem; margin: 0 0 8px; }
.card-meta { font-size: .78rem; color: var(--color-ink-soft); margin-bottom: 8px; }
.card-excerpt { font-size: .9rem; color: var(--color-ink-soft); }

/* Reader page (single ebook) */
.reader-header { text-align: center; margin-bottom: 26px; }
.reader-header h1 { margin-bottom: 6px; }
.reader-header .reader-meta { color: var(--color-ink-soft); font-size: .9rem; }

/* Quote block, echoing the "torn paper quote strip" from the brand reference */
.pull-quote {
	background: var(--color-quote-bg);
	border-radius: 10px;
	padding: 28px 34px;
	font-family: var(--font-heading);
	font-size: 1.15rem;
	color: var(--color-ink);
	text-align: center;
	margin: 36px 0;
}

/* Footer */
.site-footer {
	background: var(--color-panel);
	border-top: 1px solid var(--color-border);
	margin-top: 60px;
	padding: 46px 28px 26px;
}
.footer-inner {
	max-width: 1160px;
	margin: 0 auto;
	display: grid;
	grid-template-columns: 1.4fr 1fr 1fr 1fr;
	gap: 30px;
}
.footer-inner h4 { font-size: .95rem; margin-bottom: 12px; }
.footer-inner ul { list-style: none; margin: 0; padding: 0; }
.footer-inner li { margin-bottom: 8px; }
.footer-inner a { color: var(--color-ink-soft); font-size: .88rem; }
.footer-bottom {
	max-width: 1160px;
	margin: 30px auto 0;
	padding-top: 20px;
	border-top: 1px solid var(--color-border);
	font-size: .8rem;
	color: var(--color-ink-soft);
	text-align: center;
}

/* Accessibility: comfortable focus states for keyboard readers */
a:focus-visible, button:focus-visible {
	outline: 2px solid var(--color-accent);
	outline-offset: 2px;
}

/* =====================================================================
   Responsive
   ===================================================================== */
@media (max-width: 880px) {
	.hero-section { grid-template-columns: 1fr; padding: 34px 24px; }
	.feature-grid { grid-template-columns: 1fr; }
	.footer-inner { grid-template-columns: 1fr 1fr; }
	.main-navigation { display: none; width: 100%; order: 3; }
	.main-navigation.is-open { display: block; }
	.main-navigation ul { flex-direction: column; gap: 4px; padding: 14px 0; }
	.menu-toggle { display: inline-flex; }
}
@media (max-width: 560px) {
	.footer-inner { grid-template-columns: 1fr; }
	.site-header-inner { padding: 14px 18px; }
	.site-content { padding: 24px 18px 60px; }
}