@charset "UTF-8";

/* 练题官网 — 静态 HTML 企业站风格 */

*,
*::before,
*::after {
	box-sizing: border-box;
}

html {
	scroll-behavior: smooth;
	-webkit-text-size-adjust: 100%;
	text-size-adjust: 100%;
}

body {
	margin: 0;
	font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
	font-size: 15px;
	line-height: 1.65;
	color: #1a1d26;
	background: #fff;
	-webkit-tap-highlight-color: transparent;
}

a {
	color: #0d6efd;
	text-decoration: none;
}

a:hover {
	text-decoration: underline;
}

/* Header（窄屏 ≤639px：汉堡菜单，覆盖 iPhone X 375×812 等级机型；配合 viewport-fit=cover 与安全区） */
.site-header {
	position: sticky;
	top: 0;
	z-index: 200;
	background: rgba(255, 255, 255, 0.96);
	border-bottom: 1px solid #e8eaef;
	backdrop-filter: blur(8px);
	padding-top: env(safe-area-inset-top, 0px);
}

.site-header__inner {
	max-width: 1120px;
	margin: 0 auto;
	padding-left: max(20px, env(safe-area-inset-left, 0px));
	padding-right: max(20px, env(safe-area-inset-right, 0px));
	padding-top: 0;
	padding-bottom: 0;
	min-height: 56px;
	height: auto;
	display: flex;
	align-items: center;
	gap: 16px;
	flex-wrap: nowrap;
}

.site-nav__toggle-input {
	position: absolute;
	width: 1px;
	height: 1px;
	padding: 0;
	margin: -1px;
	overflow: hidden;
	clip: rect(0, 0, 0, 0);
	white-space: nowrap;
	border: 0;
	opacity: 0;
	pointer-events: none;
}

.site-nav__toggle {
	display: none;
	align-items: center;
	justify-content: center;
	flex-shrink: 0;
	width: 44px;
	height: 44px;
	margin: -6px -8px -6px 0;
	cursor: pointer;
	border-radius: 10px;
	color: inherit;
}

.site-nav__toggle:hover {
	background: #f3f4f6;
}

.site-nav__toggle:focus-visible {
	outline: 2px solid #0d6efd;
	outline-offset: 2px;
}

.site-nav__burger {
	display: flex;
	flex-direction: column;
	justify-content: center;
	align-items: center;
	gap: 5px;
	width: 22px;
	height: 22px;
}

.site-nav__burger span {
	display: block;
	width: 22px;
	height: 2px;
	background: #111827;
	border-radius: 1px;
	transition: transform 0.22s ease, opacity 0.18s ease;
}

.site-nav__toggle-input:checked + .site-nav__toggle .site-nav__burger span:nth-child(1) {
	transform: translateY(7px) rotate(45deg);
}

.site-nav__toggle-input:checked + .site-nav__toggle .site-nav__burger span:nth-child(2) {
	opacity: 0;
}

.site-nav__toggle-input:checked + .site-nav__toggle .site-nav__burger span:nth-child(3) {
	transform: translateY(-7px) rotate(-45deg);
}

.site-logo {
	display: inline-flex;
	align-items: center;
	gap: 10px;
	font-size: 20px;
	font-weight: 700;
	color: #111827;
	text-decoration: none;
	letter-spacing: 0.02em;
	min-width: 0;
}

.site-logo:hover {
	text-decoration: none;
	color: #0d6efd;
}

.site-logo__img {
	display: none;
	height: 36px;
	width: auto;
	max-width: 120px;
	object-fit: contain;
	border-radius: 8px;
	flex-shrink: 0;
}

.site-logo__img.is-visible {
	display: block;
}

.site-logo__text {
	white-space: nowrap;
	overflow: hidden;
	text-overflow: ellipsis;
	max-width: 9em;
}

.site-nav {
	flex: 1;
}

.site-nav ul {
	margin: 0;
	padding: 0;
	list-style: none;
	display: flex;
	flex-wrap: wrap;
	gap: 8px 20px;
	justify-content: center;
}

.site-nav a {
	color: #374151;
	font-size: 14px;
	text-decoration: none;
}

.site-nav a:hover {
	color: #0d6efd;
	text-decoration: none;
}

@media (min-width: 640px) {
	.site-nav__toggle {
		display: none !important;
	}
}

@media (max-width: 639px) {
	.site-header__inner {
		flex-wrap: wrap;
		align-items: center;
		padding-top: 10px;
		padding-bottom: 10px;
		row-gap: 0;
		column-gap: 12px;
	}

	.site-logo {
		flex: 1;
		min-width: 0;
	}

	.site-nav__toggle {
		display: inline-flex;
	}

	.site-nav {
		order: 3;
		flex: 1 1 100%;
		width: 100%;
		max-height: 0;
		overflow: hidden;
		transition: max-height 0.3s ease, padding 0.3s ease, border-color 0.2s ease;
		border-top: 1px solid transparent;
		padding-top: 0;
		padding-bottom: 0;
	}

	.site-nav__toggle-input:checked ~ .site-nav {
		max-height: min(72vh, 340px);
		border-top-color: #e8eaef;
		padding-top: 6px;
		padding-bottom: max(10px, env(safe-area-inset-bottom, 0px));
	}

	.site-nav ul {
		flex-direction: column;
		flex-wrap: nowrap;
		gap: 0;
		align-items: stretch;
		justify-content: flex-start;
	}

	.site-nav li {
		border-bottom: 1px solid #f3f4f6;
	}

	.site-nav li:last-child {
		border-bottom: none;
	}

	.site-nav a {
		display: block;
		padding: 14px 2px;
		font-size: 16px;
		line-height: 1.35;
	}

	.site-nav a:hover {
		color: #0d6efd;
	}
}

@media (min-width: 640px) and (max-width: 900px) {
	.site-nav ul {
		gap: 8px 14px;
	}

	.site-nav a {
		font-size: 13px;
	}
}

/* Hero */
.hero {
	background: linear-gradient(160deg, #0f172a 0%, #1e3a5f 45%, #0d6efd 100%);
	color: #fff;
	padding: 56px 20px 64px;
}

.hero__inner {
	max-width: 1120px;
	margin: 0 auto;
}

.hero__eyebrow {
	margin: 0 0 12px;
	font-size: 11px;
	letter-spacing: 0.2em;
	color: rgba(255, 255, 255, 0.55);
}

.hero__logo {
	display: none;
	max-height: 72px;
	width: auto;
	max-width: min(280px, 85vw);
	object-fit: contain;
	margin: 0 0 20px;
	border-radius: 12px;
}

.hero__logo.is-visible {
	display: block;
}

.hero__title {
	margin: 0 0 16px;
	font-size: clamp(32px, 6vw, 44px);
	font-weight: 700;
	line-height: 1.15;
	letter-spacing: 0.02em;
}

.hero__lead {
	margin: 0 0 28px;
	max-width: 36em;
	font-size: 16px;
	line-height: 1.75;
	color: rgba(255, 255, 255, 0.88);
}

.hero__actions {
	display: flex;
	flex-wrap: wrap;
	gap: 12px;
	margin-bottom: 40px;
}

.btn {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	padding: 10px 22px;
	font-size: 15px;
	font-weight: 600;
	border-radius: 8px;
	text-decoration: none;
	border: 2px solid transparent;
	cursor: pointer;
	transition: background 0.15s, border-color 0.15s, color 0.15s;
}

.btn:hover {
	text-decoration: none;
}

.btn--primary {
	color: #fff;
	background: #fff;
	color: #0d6efd;
}

.btn--primary:hover {
	background: #f0f6ff;
	color: #0a58c4;
}

.btn--ghost {
	color: #fff;
	border-color: rgba(255, 255, 255, 0.45);
	background: transparent;
}

.btn--ghost:hover {
	background: rgba(255, 255, 255, 0.1);
	border-color: #fff;
	color: #fff;
}

.btn--outline {
	color: #0d6efd;
	border-color: #0d6efd;
	background: #fff;
}

.btn--outline:hover {
	background: #e7f1ff;
}

.btn--lg {
	padding: 12px 28px;
	font-size: 15px;
}

.hero__highlights {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 12px;
	margin: 0;
	padding: 0;
	list-style: none;
	max-width: 720px;
}

.hero__highlights li {
	padding: 14px 16px;
	background: rgba(255, 255, 255, 0.1);
	border: 1px solid rgba(255, 255, 255, 0.15);
	border-radius: 10px;
}

.hero__highlights-k {
	display: block;
	font-size: 14px;
	font-weight: 600;
	margin-bottom: 4px;
}

.hero__highlights-v {
	font-size: 12px;
	color: rgba(255, 255, 255, 0.7);
}

@media (max-width: 640px) {
	.hero__highlights {
		grid-template-columns: 1fr;
	}
}

/* Content blocks */
.block {
	padding: 56px 20px;
}

.block--white {
	background: #fff;
}

.block--gray {
	background: #f4f6f9;
}

.block__inner {
	max-width: 1120px;
	margin: 0 auto;
}

.block__inner--narrow {
	max-width: 640px;
	text-align: center;
}

.block__head {
	margin-bottom: 36px;
	text-align: center;
	max-width: 640px;
	margin-left: auto;
	margin-right: auto;
}

.block__label {
	margin: 0 0 8px;
	font-size: 11px;
	letter-spacing: 0.18em;
	color: #6b7280;
}

.block__title {
	margin: 0 0 12px;
	font-size: 26px;
	font-weight: 700;
	color: #111827;
}

.block__desc {
	margin: 0;
	font-size: 15px;
	color: #6b7280;
	line-height: 1.7;
}

.grid-3 {
	margin: 0;
	padding: 0;
	list-style: none;
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 20px;
}

@media (max-width: 900px) {
	.grid-3 {
		grid-template-columns: 1fr;
	}
}

.card {
	padding: 24px 22px;
	background: #f9fafb;
	border: 1px solid #e5e7eb;
	border-radius: 12px;
}

.card__title {
	margin: 0 0 10px;
	font-size: 17px;
	font-weight: 600;
	color: #111827;
}

.card__text {
	margin: 0;
	font-size: 14px;
	color: #4b5563;
	line-height: 1.65;
}

/* 适用场景 */
.scenes {
	margin: 0;
	padding: 0;
	list-style: none;
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	gap: 20px;
}

@media (max-width: 900px) {
	.scenes {
		grid-template-columns: 1fr;
	}
}

.scene {
	margin: 0;
	padding: 22px 22px 20px;
	background: #fff;
	border: 1px solid #e5e7eb;
	border-radius: 12px;
	box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
}

.scene__title {
	margin: 0 0 10px;
	font-size: 17px;
	font-weight: 600;
	color: #111827;
	line-height: 1.35;
}

.scene__desc {
	margin: 0 0 14px;
	font-size: 14px;
	color: #4b5563;
	line-height: 1.7;
}

.scene__points {
	margin: 0;
	padding-left: 18px;
	color: #374151;
	font-size: 13px;
	line-height: 1.65;
}

.scene__points li {
	margin-bottom: 6px;
}

.scene__points li:last-child {
	margin-bottom: 0;
}

/* Support */
.block--support .block__head {
	margin-bottom: 32px;
}

.support-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 20px;
	margin-bottom: 44px;
}

@media (max-width: 900px) {
	.support-grid {
		grid-template-columns: 1fr;
	}
}

.support-card {
	padding: 22px 22px 24px;
	background: #f9fafb;
	border: 1px solid #e5e7eb;
	border-radius: 12px;
	border-top: 3px solid #0d6efd;
}

.support-card__title {
	margin: 0 0 12px;
	font-size: 16px;
	font-weight: 600;
	color: #111827;
}

.support-card__main {
	margin: 0 0 10px;
	font-size: 15px;
	font-weight: 500;
	color: #1f2937;
}

.support-card__main a {
	color: #0d6efd;
	font-weight: 600;
}

.support-card__sub {
	margin: 0;
	font-size: 13px;
	color: #6b7280;
	line-height: 1.6;
}

.faq {
	max-width: 720px;
	margin: 0 auto;
	border-top: 1px solid #e5e7eb;
	padding-top: 28px;
}

.faq__title {
	margin: 0 0 16px;
	font-size: 18px;
	font-weight: 600;
	color: #111827;
}

.faq__item {
	margin-bottom: 10px;
	border: 1px solid #e5e7eb;
	border-radius: 10px;
	background: #fff;
	overflow: hidden;
}

.faq__item summary {
	padding: 14px 18px;
	font-size: 15px;
	font-weight: 500;
	color: #374151;
	cursor: pointer;
	list-style: none;
}

.faq__item summary::-webkit-details-marker {
	display: none;
}

.faq__item summary::after {
	content: "+";
	float: right;
	color: #9ca3af;
	font-weight: 400;
}

.faq__item[open] summary::after {
	content: "−";
}

.faq__item p {
	margin: 0;
	padding: 0 18px 16px;
	font-size: 14px;
	color: #6b7280;
	line-height: 1.65;
	border-top: 1px solid #f3f4f6;
	padding-top: 12px;
}

/* CTA strip */
.block--cta {
	background: #0f172a;
	color: #fff;
	padding: 48px 20px 56px;
}

.cta__title {
	margin: 0 0 12px;
	font-size: 24px;
	font-weight: 700;
}

.cta__text {
	margin: 0 0 24px;
	font-size: 14px;
	color: rgba(255, 255, 255, 0.75);
	line-height: 1.7;
}

.cta__actions {
	display: flex;
	flex-wrap: wrap;
	gap: 12px;
	justify-content: center;
}

.block--cta .btn--primary {
	background: #0d6efd;
	color: #fff;
}

.block--cta .btn--primary:hover {
	background: #0b5ed7;
	color: #fff;
}

.block--cta .btn--outline {
	border-color: rgba(255, 255, 255, 0.5);
	color: #fff;
	background: transparent;
}

.block--cta .btn--outline:hover {
	background: rgba(255, 255, 255, 0.08);
	border-color: #fff;
	color: #fff;
}

/* Footer */
.site-footer {
	background: #111827;
	color: #9ca3af;
	padding: 40px 20px 32px;
	font-size: 13px;
}

.site-footer__inner {
	max-width: 1120px;
	margin: 0 auto;
	text-align: center;
}

.site-footer__brand-wrap {
	display: flex;
	flex-direction: column;
	align-items: center;
	gap: 10px;
	margin: 0 0 16px;
}

.site-footer__logo {
	display: none;
	height: 44px;
	width: auto;
	max-width: 160px;
	object-fit: contain;
	border-radius: 8px;
}

.site-footer__logo.is-visible {
	display: block;
}

.site-footer__brand {
	margin: 0;
	font-size: 18px;
	font-weight: 700;
	color: #fff;
	letter-spacing: 0.04em;
}

.site-footer__links {
	margin: 0 0 20px;
	padding: 0;
	list-style: none;
	display: flex;
	flex-wrap: wrap;
	gap: 8px 20px;
	justify-content: center;
}

.site-footer__links a {
	color: #d1d5db;
	text-decoration: none;
}

.site-footer__links a:hover {
	color: #fff;
	text-decoration: none;
}

.site-footer__icp {
	margin: 0 0 8px;
}

.site-footer__icp a {
	color: #9ca3af;
}

.site-footer__icp a:hover {
	color: #e5e7eb;
}

.site-footer__copy {
	margin: 0;
	font-size: 12px;
	color: #6b7280;
}

.privacy-teaser__actions {
	margin: 0;
	text-align: center;
}