@charset "UTF-8";

/* ==========================================================================
   技術コラムアーカイブ
   ========================================================================== */


/* ---------- リード文 ---------- */

.column-archive__lead {
	max-width: var(--content-narrow);
	margin: 0 auto 48px;
	text-align: center;
	font-size: 0.9375rem;
	line-height: 1.8;
	color: var(--color-text-light);
}


/* ---------- カテゴリフィルター ---------- */

.column-filter {
	margin-bottom: 48px;
}

.column-filter__tabs {
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	gap: 8px;
}

.column-filter__btn {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	padding: 10px 24px;
	font-size: 0.875rem;
	font-weight: 500;
	letter-spacing: 0.03em;
	color: var(--color-text);
	background-color: var(--color-bg);
	border: 1px solid var(--color-border);
	border-radius: var(--radius);
	text-decoration: none;
	transition: background-color var(--transition), color var(--transition), border-color var(--transition);
	white-space: nowrap;
}

.column-filter__btn:hover {
	border-color: var(--color-primary);
	color: var(--color-primary);
}

.column-filter__btn.is-active {
	background-color: var(--color-primary);
	border-color: var(--color-primary);
	color: var(--color-text-on-dark);
}


/* ---------- カードグリッド ---------- */

.column-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 32px 24px;
}

.column-card {
	background-color: var(--color-bg);
	border: 1px solid var(--color-border);
	border-radius: var(--radius);
	overflow: hidden;
	transition: transform var(--transition), box-shadow var(--transition);
}

.column-card:hover {
	transform: translateY(-4px);
	box-shadow: 0 10px 24px rgba(28, 53, 87, 0.08);
}

.column-card__link {
	display: block;
	color: inherit;
	text-decoration: none;
}

.column-card__image {
	position: relative;
	aspect-ratio: 3 / 2;
	overflow: hidden;
	background-color: var(--color-bg-alt);
}

.column-card__image img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	transition: transform 0.4s ease;
}

.column-card:hover .column-card__image img {
	transform: scale(1.05);
}

.column-card__tag {
	position: absolute;
	top: 12px;
	left: 12px;
	padding: 4px 12px;
	font-size: 0.75rem;
	font-weight: 500;
	color: var(--color-text-on-dark);
	background-color: var(--color-primary);
	border-radius: var(--radius);
}

.column-card__body {
	padding: 20px;
}

.column-card__date {
	display: block;
	font-family: var(--font-number);
	font-size: 0.8125rem;
	color: var(--color-text-light);
	letter-spacing: 0.05em;
	margin-bottom: 8px;
}

.column-card__title {
	font-size: 1.0625rem;
	font-weight: 700;
	line-height: 1.6;
	color: var(--color-primary);
	margin-bottom: 10px;
}

.column-card__excerpt {
	font-size: 0.875rem;
	line-height: 1.7;
	color: var(--color-text-light);
}


/* ---------- 空状態 ---------- */

.column-archive__empty {
	text-align: center;
	padding: 64px 0;
	color: var(--color-text-light);
}


/* ---------- SP ---------- */

@media (max-width: 768px) {
	.column-archive__lead {
		margin-bottom: 32px;
		font-size: 0.875rem;
		text-align: left;
	}

	.column-filter {
		margin-bottom: 32px;
	}

	.column-filter__tabs {
		justify-content: flex-start;
		flex-wrap: nowrap;
		overflow-x: auto;
		padding-bottom: 4px;
		-webkit-overflow-scrolling: touch;
	}

	.column-filter__btn {
		padding: 8px 18px;
		font-size: 0.8125rem;
	}

	.column-grid {
		grid-template-columns: 1fr;
		gap: 24px;
	}

	.column-card__body {
		padding: 16px;
	}

	.column-card__title {
		font-size: 1rem;
	}
}