/* ============================================================
   bellup — 「校閲される一枚の原稿」
   紙(生成り) × 墨 × 朱(校正印)。散らばったメモが、
   事実確認済みの一通に揃うまでを、紙の上で見せる。
   ============================================================ */

:root {
	color-scheme: light;
	--paper: #f7f4ed;
	--sheet: #fffdf8;
	--ink: #211d17;
	--ink-muted: #5f5749;
	--shu: #c73a20;
	--shu-deep: #a02c15;
	--shu-soft: rgba(199, 58, 32, 0.16);
	--hair: #ddd5c6;
	--ink-bg: #1d1a15;
	--paper-on-ink: #f2eee4;
	--muted-on-ink: #b3aa98;

	font-family: "Helvetica Neue", Helvetica, Arial, "Hiragino Kaku Gothic ProN",
		"Hiragino Sans", "Noto Sans JP", sans-serif;
	background: var(--paper);
	color: var(--ink);
}

* {
	box-sizing: border-box;
}

body {
	margin: 0;
	min-height: 100vh;
	line-height: 2;
	overflow-x: hidden;
}

/* --- 紙の空気: 穏やかに漂う多色の淡い光 + グレイン --- */
body::before {
	content: "";
	position: fixed;
	inset: -40%;
	z-index: -1;
	pointer-events: none;
	background: radial-gradient(
			42% 36% at 22% 24%,
			rgba(199, 58, 32, 0.07),
			transparent 70%
		),
		radial-gradient(
			46% 40% at 80% 18%,
			rgba(212, 164, 62, 0.09),
			transparent 70%
		),
		radial-gradient(
			50% 44% at 70% 82%,
			rgba(63, 96, 138, 0.07),
			transparent 70%
		);
	animation: drift 48s ease-in-out infinite alternate;
}

body::after {
	content: "";
	position: fixed;
	inset: 0;
	z-index: 40;
	pointer-events: none;
	background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.045'/%3E%3C/svg%3E");
}

@keyframes drift {
	from {
		transform: translate3d(-3%, -2%, 0) scale(1);
	}
	to {
		transform: translate3d(3%, 3%, 0) scale(1.06);
	}
}

a {
	color: inherit;
	text-decoration: none;
}

::selection {
	background: var(--shu-soft);
}

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

/* ---------- Typography ---------- */
h1,
h2,
h3,
p {
	margin: 0;
}

h1 {
	font-size: clamp(2.375rem, 5.6vw, 4.25rem);
	font-weight: 700;
	line-height: 1.28;
	letter-spacing: 0.01em;
}

h2 {
	font-size: clamp(1.5rem, 3vw, 2.25rem);
	font-weight: 700;
	line-height: 1.45;
	letter-spacing: 0.01em;
}

h3 {
	font-size: 1.125rem;
	font-weight: 700;
	line-height: 1.6;
}

.lead {
	font-size: 1.0625rem;
	font-weight: 400;
	line-height: 2.1;
	color: var(--ink-muted);
}

.caption {
	font-size: 0.8125rem;
	line-height: 1.7;
	color: var(--ink-muted);
}

.eyebrow {
	display: inline-flex;
	align-items: center;
	gap: 14px;
	font-size: 0.75rem;
	font-weight: 700;
	letter-spacing: 0.24em;
	text-transform: uppercase;
	color: var(--shu-deep);
}

.eyebrow::before {
	content: "";
	width: 36px;
	height: 1px;
	background: var(--shu);
	flex: none;
}

/* 朱のマーカー(校閲の傍線) */
.hl {
	background: linear-gradient(
		transparent 58%,
		var(--shu-soft) 58%,
		var(--shu-soft) 94%,
		transparent 94%
	);
}

.center {
	text-align: center;
}

.measure {
	max-width: 720px;
	margin-inline: auto;
}

/* ---------- Header ---------- */
.site-header {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 16px;
	height: 84px;
	max-width: 1080px;
	margin-inline: auto;
	padding-inline: 28px;
}

.brand {
	font-size: 1.375rem;
	font-weight: 700;
	letter-spacing: -0.01em;
}

/* 朱肉の検印スタンプ */
.status-badge {
	border: 1.5px solid var(--shu-deep);
	border-radius: 3px;
	color: var(--shu-deep);
	font-size: 0.75rem;
	font-weight: 700;
	letter-spacing: 0.1em;
	padding: 5px 12px;
	transform: rotate(-3deg);
}

/* ---------- Sections base ---------- */
section {
	padding: 128px 28px;
}

section > * + * {
	margin-top: 28px;
}

.section {
	border-top: 1px solid var(--hair);
	max-width: 1080px;
	margin-inline: auto;
}

.hero {
	max-width: 1080px;
	margin-inline: auto;
	padding-top: clamp(72px, 12vh, 144px);
	padding-bottom: 128px;
	text-align: left;
}

.hero h1 {
	max-width: 18em;
}

.hero .lead {
	max-width: 36em;
}

.cta-row {
	display: flex;
	gap: 12px;
	padding-top: 12px;
}

.cta-row.center {
	justify-content: center;
}

.cta-note {
	margin-top: 12px;
}

/* ---------- Button ---------- */
.button {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	border-radius: 3px;
	padding: 15px 34px;
	font-family: inherit;
	font-size: 0.9375rem;
	font-weight: 700;
	letter-spacing: 0.08em;
	line-height: 1;
	border: 1px solid transparent;
	cursor: pointer;
}

.button.disabled,
.button[aria-disabled="true"] {
	background: transparent;
	border: 1px dashed var(--ink-muted);
	color: var(--ink-muted);
	cursor: default;
}

.button:focus-visible {
	outline: 2px solid var(--shu-deep);
	outline-offset: 2px;
}

/* ---------- 4-2 課題: 机に散らばったメモ ---------- */
.problem {
	text-align: left;
}

.problem .measure {
	margin-inline: 0;
	max-width: 640px;
}

.chip-list {
	display: flex;
	flex-wrap: wrap;
	gap: 20px 24px;
	max-width: 720px;
	margin: 56px 0 0;
	padding: 0;
	list-style: none;
}

.chip {
	background: var(--sheet);
	border: 1px solid var(--hair);
	border-radius: 2px;
	padding: 14px 22px;
	font-size: 0.9375rem;
	line-height: 1;
	box-shadow: 0 10px 24px rgba(33, 29, 23, 0.09);
}

.chip:nth-child(1) {
	transform: rotate(-3.5deg) translateY(4px);
	background: #fdf8ea;
}

.chip:nth-child(2) {
	transform: rotate(2deg) translateY(-8px);
}

.chip:nth-child(3) {
	transform: rotate(-1.5deg) translateY(10px);
	background: #f2f4f8;
}

.chip:nth-child(4) {
	transform: rotate(3deg) translateY(-4px);
	background: #faf1ec;
}

/* ---------- 4-2.5 返信依頼の流れ ---------- */
.workflow .measure {
	max-width: 760px;
}

.workflow-steps {
	display: grid;
	grid-template-columns: repeat(3, minmax(0, 1fr));
	gap: 32px;
	margin: 64px 0 0;
}

.workflow-step {
	border-top: 1px solid var(--ink);
	padding-top: 20px;
}

.workflow-step > * + * {
	margin-top: 12px;
}

.step-number {
	font-family: ui-monospace, "SF Mono", Menlo, monospace;
	font-size: 0.75rem;
	letter-spacing: 0.12em;
	color: var(--shu-deep);
}

.workflow-step p {
	color: var(--ink-muted);
	font-size: 0.9375rem;
	line-height: 1.8;
}

.reply-ui {
	max-width: 860px;
	margin: 72px auto 0;
	padding: 0;
	background: #292b2c;
	border: 1px solid #737575;
	border-radius: 18px;
	box-shadow: 0 24px 60px rgba(33, 29, 23, 0.2);
	color: #f4f2ed;
	overflow: hidden;
}

.reply-ui-topbar {
	display: flex;
	align-items: center;
	justify-content: space-between;
	padding: 20px 28px;
	border-bottom: 1px solid rgba(244, 242, 237, 0.16);
	color: #c9c7c2;
}

.reply-ui-back {
	font-size: 2rem;
	font-weight: 300;
	line-height: 0.6;
}

.reply-ui-title {
	font-size: 0.875rem;
	font-weight: 700;
	letter-spacing: 0.08em;
}

.reply-ui-brand {
	font-size: 0.8125rem;
	font-weight: 700;
	color: #f4f2ed;
}

.reply-ui-body {
	display: grid;
	grid-template-columns: 150px 1fr;
	gap: 28px;
	align-items: start;
	padding: 48px 56px 28px;
}

.reply-ui-label {
	padding-top: 12px;
	color: #b4b2ae;
	font-size: 0.875rem;
	font-weight: 700;
}

.reply-ui-message {
	border: 2px solid #777978;
	border-radius: 16px;
	padding: 20px 26px;
	font-size: 1.05rem;
	line-height: 1.7;
}

.reply-ui-message strong {
	display: block;
	font-size: 1.05rem;
}

.reply-ui-message strong span {
	font-weight: 400;
	color: #b4b2ae;
	font-size: 0.875rem;
}

.reply-ui-message p {
	margin-top: 6px;
}

.reply-ui-context {
	display: flex;
	flex-wrap: wrap;
	gap: 8px;
	padding: 0 56px 28px 234px;
	color: #d3d0c9;
	font-size: 0.75rem;
}

.reply-ui-context span:not(.context-label) {
	padding: 5px 9px;
	border: 1px solid rgba(244, 242, 237, 0.25);
	border-radius: 3px;
}

.context-label {
	width: 100%;
	color: #b4b2ae;
	font-weight: 700;
}

.reply-ui-task {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 20px;
	margin: 0 56px;
	padding: 18px 20px;
	border-left: 2px solid var(--shu);
	background: rgba(199, 58, 32, 0.1);
}

.task-kicker {
	font-size: 0.7rem;
	font-weight: 700;
	letter-spacing: 0.12em;
	color: #e78b78;
}

.reply-ui-task p {
	margin-top: 4px;
	font-size: 0.875rem;
	color: #ede9e0;
}

.task-status {
	flex: none;
	font-size: 0.75rem;
	color: #e78b78;
}

.reply-ui-actions {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 20px;
	padding: 28px 56px 36px;
}

.reply-ui-hint {
	color: #aaa7a1;
	font-size: 0.75rem;
}

.reply-ui-button {
	display: inline-flex;
	align-items: center;
	gap: 12px;
	padding: 12px 18px;
	border: 1px solid #5b5d5d;
	border-radius: 999px;
	font-size: 0.8125rem;
	font-weight: 700;
}

.reply-ui-button span {
	color: #aaa7a1;
	font-size: 0.7rem;
}

/* ---------- 4-3 答え: 校閲済みの一枚 ---------- */
.answer .measure {
	display: flex;
	flex-direction: column;
	gap: 20px;
	align-items: center;
}

.mock {
	max-width: 640px;
	margin: 56px auto 0;
	background: var(--sheet);
	border: 1px solid var(--hair);
	border-radius: 2px;
	box-shadow: 0 24px 60px rgba(33, 29, 23, 0.12);
	padding: 44px 48px 48px;
	position: relative;
}

.mock::before {
	content: "";
	position: absolute;
	top: 0;
	left: 48px;
	right: 48px;
	height: 1px;
	background: var(--shu);
	opacity: 0.55;
}

.mock-facts {
	display: flex;
	flex-wrap: wrap;
	gap: 12px;
}

.fact-chip {
	display: inline-flex;
	align-items: center;
	gap: 8px;
	background: transparent;
	color: var(--shu-deep);
	border: 1.5px solid var(--shu-deep);
	border-radius: 3px;
	padding: 7px 14px;
	font-size: 0.8125rem;
	font-weight: 700;
	letter-spacing: 0.06em;
	line-height: 1;
}

.fact-chip:nth-child(1) {
	transform: rotate(-1.5deg);
}

.fact-chip:nth-child(2) {
	transform: rotate(1deg);
}

.fact-chip .ic {
	width: 14px;
	height: 14px;
}

.mock-reply {
	margin-top: 28px;
	border-left: 2px solid var(--shu);
	padding-left: 24px;
}

.mock-reply p {
	font-size: 1rem;
	line-height: 2.2;
}

/* ---------- 4-4 理由: 罫線だけの三段組 ---------- */
.card-grid {
	display: grid;
	grid-template-columns: repeat(3, minmax(0, 1fr));
	gap: 48px;
	margin-top: 64px;
}

.reason-card {
	border-top: 1px solid var(--ink);
	padding-top: 28px;
}

.reason-card > * + * {
	margin-top: 14px;
}

.reason-ic {
	display: inline-flex;
	color: var(--shu-deep);
}

.reason-ic svg {
	width: 24px;
	height: 24px;
}

.reason-card p {
	color: var(--ink-muted);
	font-size: 0.9375rem;
}

/* ---------- 4-5 クロージング: 墨 ---------- */
.closing {
	background: var(--ink-bg);
	color: var(--paper-on-ink);
	padding: 152px 28px;
	text-align: center;
}

.closing .measure > * + * {
	margin-top: 28px;
}

.closing p {
	color: var(--muted-on-ink);
}

.closing .button.disabled,
.closing .button[aria-disabled="true"] {
	border-color: var(--muted-on-ink);
	color: var(--paper-on-ink);
}

.closing .button:focus-visible {
	outline-color: var(--paper-on-ink);
}

/* ---------- Footer ---------- */
footer {
	background: var(--ink-bg);
	color: var(--muted-on-ink);
	text-align: center;
	padding: 48px 28px 56px;
	border-top: 1px solid rgba(242, 238, 228, 0.14);
}

footer > * + * {
	margin-top: 8px;
}

.footer-brand {
	font-size: 1rem;
	font-weight: 700;
	color: var(--paper-on-ink);
}

footer .caption {
	color: var(--muted-on-ink);
}

/* ---------- Responsive ---------- */
@media (max-width: 767px) {
	section {
		padding: 88px 22px;
	}

	.hero {
		padding-top: 48px;
		padding-bottom: 88px;
	}

	.site-header {
		height: 72px;
		padding-inline: 22px;
	}

	.chip-list {
		gap: 16px 14px;
		margin-top: 40px;
	}

	.mock {
		padding: 32px 26px 36px;
	}

	.mock::before {
		left: 26px;
		right: 26px;
	}

	.card-grid {
		grid-template-columns: 1fr;
		gap: 36px;
		margin-top: 48px;
	}

	.workflow-steps {
		grid-template-columns: 1fr;
		gap: 28px;
		margin-top: 48px;
	}

	.reply-ui {
		margin-top: 48px;
		border-radius: 12px;
	}

	.reply-ui-topbar {
		padding: 16px 18px;
	}

	.reply-ui-body {
		display: block;
		padding: 32px 20px 20px;
	}

	.reply-ui-label {
		padding-top: 0;
		margin-bottom: 12px;
	}

	.reply-ui-message {
		padding: 16px 18px;
		font-size: 0.9375rem;
	}

	.reply-ui-context {
		padding: 0 20px 20px;
	}

	.reply-ui-task {
		align-items: flex-start;
		flex-direction: column;
		gap: 8px;
		margin: 0 20px;
	}

	.reply-ui-actions {
		align-items: flex-start;
		flex-direction: column;
		padding: 24px 20px 28px;
	}

	.closing {
		padding: 104px 22px;
	}
}

@media (prefers-reduced-motion: reduce) {
	body::before {
		animation: none;
	}

	* {
		transition-duration: 0ms !important;
		animation-duration: 0.01ms !important;
	}
}