/* ==========================================================================
   AI4AT — публичные стили (главная, лендинг, формы login/register).
   Светлая тема, индиго-акцент.
   ========================================================================== */

:root {
	--ai4at-bg:           #f7f8fb;
	--ai4at-surface:      #ffffff;
	--ai4at-surface-2:    #f0f2f7;
	--ai4at-surface-3:    #e9ecf3;
	--ai4at-border:       #e3e6ee;
	--ai4at-border-strong:#d3d7e2;
	--ai4at-text:         #1a1d29;
	--ai4at-text-muted:   #6b7080;
	--ai4at-text-soft:    #8e94a3;
	--ai4at-accent:       #6366f1;
	--ai4at-accent-hover: #4f46e5;
	--ai4at-accent-soft:  #eef0ff;
	--ai4at-success:      #16a34a;
	--ai4at-error:        #dc2626;
	--ai4at-warning:      #f59e0b;
	--ai4at-radius-sm:    8px;
	--ai4at-radius:       12px;
	--ai4at-radius-lg:    16px;
	--ai4at-radius-xl:    20px;
	--ai4at-shadow-sm:    0 1px 2px rgba(20, 26, 45, 0.04);
	--ai4at-shadow:       0 4px 16px rgba(20, 26, 45, 0.06);
	--ai4at-shadow-lg:    0 24px 48px -12px rgba(20, 26, 45, 0.12);
	--ai4at-font:         'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

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

html { scroll-behavior: smooth; }

body.ai4at {
	margin: 0;
	font-family: var(--ai4at-font);
	font-size: 16px;
	line-height: 1.55;
	color: var(--ai4at-text);
	background: var(--ai4at-bg);
	-webkit-font-smoothing: antialiased;
	-moz-osx-font-smoothing: grayscale;
}

body.ai4at a:not(.ai4at-btn):not(.ai4at-logo):not(.ai4at-sidebar__link):not(.ai4at-tab):not(.ai4at-history__item):not(.ai4at-agent-card):not(.ai4at-header__phone):not(.ai4at-header__tg) {
	color: var(--ai4at-accent);
	text-decoration: none;
	transition: color 0.15s;
}
body.ai4at a:not(.ai4at-btn):not(.ai4at-logo):not(.ai4at-sidebar__link):not(.ai4at-tab):not(.ai4at-history__item):not(.ai4at-agent-card):not(.ai4at-header__phone):not(.ai4at-header__tg):hover { color: var(--ai4at-accent-hover); }

body.ai4at h1, body.ai4at h2, body.ai4at h3, body.ai4at h4 {
	margin: 0 0 0.5em;
	font-weight: 700;
	color: var(--ai4at-text);
	line-height: 1.2;
}

body.ai4at p { margin: 0 0 1em; }

body.ai4at button { font-family: inherit; }

/* ---------- Layout helpers ---------- */
.ai4at-container {
	width: 100%;
	max-width: 1200px;
	margin: 0 auto;
	padding: 0 24px;
}

.ai4at-container--narrow { max-width: 720px; }

/* ---------- Buttons ----------
   Высокая специфичность (body.ai4at .class), чтобы стили
   ссылок/линковых кнопок не перебивали правила.
*/
body.ai4at .ai4at-btn,
body.ai4at a.ai4at-btn,
body.ai4at button.ai4at-btn {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	gap: 8px;
	padding: 11px 22px;
	border: 1px solid transparent;
	border-radius: var(--ai4at-radius);
	background: var(--ai4at-accent);
	color: #ffffff;
	font-size: 15px;
	font-weight: 600;
	cursor: pointer;
	transition: background 0.15s, color 0.15s, border-color 0.15s, transform 0.05s;
	text-decoration: none;
	line-height: 1;
}
body.ai4at .ai4at-btn:hover,
body.ai4at a.ai4at-btn:hover,
body.ai4at button.ai4at-btn:hover {
	background: var(--ai4at-accent-hover);
	color: #ffffff;
}
body.ai4at .ai4at-btn:active { transform: translateY(1px); }
body.ai4at .ai4at-btn:disabled { opacity: 0.5; cursor: not-allowed; }

body.ai4at .ai4at-btn--ghost,
body.ai4at a.ai4at-btn--ghost {
	background: transparent;
	color: var(--ai4at-text);
	border-color: var(--ai4at-border-strong);
}
body.ai4at .ai4at-btn--ghost:hover,
body.ai4at a.ai4at-btn--ghost:hover {
	background: var(--ai4at-surface-2);
	color: var(--ai4at-text);
	border-color: var(--ai4at-border-strong);
}

body.ai4at .ai4at-btn--soft,
body.ai4at a.ai4at-btn--soft {
	background: var(--ai4at-accent-soft);
	color: var(--ai4at-accent);
}
body.ai4at .ai4at-btn--soft:hover,
body.ai4at a.ai4at-btn--soft:hover {
	background: #e0e3ff;
	color: var(--ai4at-accent-hover);
}

body.ai4at .ai4at-btn--lg { padding: 14px 28px; font-size: 16px; }
body.ai4at .ai4at-btn--sm { padding: 8px 14px; font-size: 13px; }
body.ai4at .ai4at-btn--block { width: 100%; display: flex; }

/* ---------- Forms ---------- */
.ai4at-input,
.ai4at-textarea,
.ai4at-select {
	width: 100%;
	padding: 11px 14px;
	border: 1px solid var(--ai4at-border-strong);
	border-radius: var(--ai4at-radius);
	background: var(--ai4at-surface);
	color: var(--ai4at-text);
	font-size: 15px;
	font-family: inherit;
	transition: border-color 0.15s, box-shadow 0.15s;
}

.ai4at-input:focus,
.ai4at-textarea:focus,
.ai4at-select:focus {
	outline: none;
	border-color: var(--ai4at-accent);
	box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.ai4at-textarea { min-height: 96px; resize: vertical; }

.ai4at-field { margin-bottom: 16px; }
.ai4at-field__label {
	display: block;
	font-size: 13px;
	font-weight: 600;
	color: var(--ai4at-text-muted);
	margin-bottom: 6px;
}
.ai4at-field__hint {
	font-size: 12px;
	color: var(--ai4at-text-soft);
	margin-top: 4px;
}

/* ---------- Header ---------- */
.ai4at-header {
	position: sticky;
	top: 0;
	z-index: 50;
	background: rgba(247, 248, 251, 0.85);
	backdrop-filter: saturate(180%) blur(14px);
	border-bottom: 1px solid var(--ai4at-border);
}
.ai4at-header__inner {
	display: grid;
	grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
	align-items: center;
	gap: 16px 20px;
	padding: 12px 0;
}
.ai4at-header__contact {
	justify-self: center;
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	justify-content: center;
	gap: 10px 16px;
	min-width: 0;
}
.ai4at-header__phone {
	font-size: 15px;
	font-weight: 600;
	letter-spacing: 0.01em;
	color: var(--ai4at-text);
	text-decoration: none;
	white-space: nowrap;
	transition: color 0.15s;
}
.ai4at-header__phone:hover {
	color: var(--ai4at-accent);
}
.ai4at-header__tg {
	display: inline-flex;
	align-items: center;
	gap: 8px;
	padding: 8px 14px;
	border-radius: 999px;
	font-size: 13px;
	font-weight: 600;
	color: #0a6ea0;
	background: linear-gradient(180deg, #e8f6fc 0%, #d8eef8 100%);
	border: 1px solid rgba(14, 118, 168, 0.28);
	box-shadow: 0 1px 2px rgba(14, 118, 168, 0.08);
	text-decoration: none;
	transition: background 0.15s, border-color 0.15s, box-shadow 0.15s, color 0.15s, transform 0.05s;
	white-space: nowrap;
}
.ai4at-header__tg:hover {
	color: #085a82;
	background: linear-gradient(180deg, #dff1fa 0%, #cce8f5 100%);
	border-color: rgba(14, 118, 168, 0.45);
	box-shadow: 0 2px 8px rgba(14, 118, 168, 0.12);
}
.ai4at-header__tg:active { transform: translateY(1px); }
.ai4at-header__tg-icon {
	flex-shrink: 0;
	display: block;
}
.ai4at-header__tg-short { display: none; }
.ai4at-logo {
	justify-self: start;
	display: inline-flex;
	align-items: center;
	gap: 10px;
	font-weight: 700;
	font-size: 18px;
	color: var(--ai4at-text);
}
.ai4at-logo:hover { color: var(--ai4at-text); }
.ai4at-logo__mark {
	width: 32px;
	height: 32px;
	border-radius: 9px;
	display: inline-flex;
	align-items: center;
	justify-content: center;
	background: transparent;
	overflow: hidden;
	flex-shrink: 0;
}
.ai4at-logo__mark-img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	display: block;
	border-radius: 9px;
}

.ai4at-nav {
	justify-self: end;
	display: flex;
	flex-wrap: wrap;
	gap: 8px;
	align-items: center;
	justify-content: flex-end;
}
.ai4at-nav__link {
	padding: 8px 14px;
	border-radius: var(--ai4at-radius-sm);
	color: var(--ai4at-text-muted);
	font-weight: 500;
	font-size: 14px;
}
.ai4at-nav__link:hover { color: var(--ai4at-text); background: var(--ai4at-surface-2); }

/* Главная: шапка не закрепляется при скролле */
body.home .ai4at-header {
	position: static;
	backdrop-filter: none;
	background: var(--ai4at-bg);
}

@media (max-width: 720px) {
	.ai4at-header__inner {
		display: flex;
		flex-direction: column;
		align-items: stretch;
		gap: 12px;
		padding: 14px 0;
	}
	.ai4at-logo {
		align-self: flex-start;
	}
	.ai4at-nav {
		display: grid;
		grid-template-columns: 1fr 1fr;
		gap: 8px;
		width: 100%;
	}
	.ai4at-nav__link,
	.ai4at-nav .ai4at-btn {
		justify-content: center;
		width: 100%;
		text-align: center;
	}
	.ai4at-nav__link {
		display: flex;
		align-items: center;
	}
	.ai4at-header__contact {
		display: grid;
		grid-template-columns: 1fr 1fr;
		gap: 8px;
		width: 100%;
		padding-top: 0;
		border-top: none;
	}
	.ai4at-header__phone {
		display: flex;
		align-items: center;
		justify-content: center;
		padding: 10px 12px;
		border-radius: var(--ai4at-radius);
		background: var(--ai4at-surface);
		border: 1px solid var(--ai4at-border);
		font-size: 13px;
	}
	.ai4at-header__tg {
		justify-content: center;
		width: 100%;
		padding: 10px 12px;
		font-size: 13px;
	}
	.ai4at-header__tg-long { display: none; }
	.ai4at-header__tg-short { display: inline; }
}

/* ---------- Hero ---------- */
.ai4at-hero {
	position: relative;
	min-height: calc(100vh - 64px);
	display: flex;
	align-items: center;
	overflow: hidden;
	padding: 44px 0 60px;
}

.ai4at-hero::before,
.ai4at-hero::after {
	content: '';
	position: absolute;
	border-radius: 50%;
	filter: blur(80px);
	pointer-events: none;
	z-index: 0;
}
.ai4at-hero::before {
	width: 520px; height: 520px;
	background: rgba(99, 102, 241, 0.18);
	top: -120px; left: -120px;
}
.ai4at-hero::after {
	width: 460px; height: 460px;
	background: rgba(168, 85, 247, 0.14);
	bottom: -160px; right: -120px;
}

.ai4at-hero__grid {
	position: absolute; inset: 0;
	background-image:
		linear-gradient(rgba(28, 36, 60, 0.04) 1px, transparent 1px),
		linear-gradient(90deg, rgba(28, 36, 60, 0.04) 1px, transparent 1px);
	background-size: 56px 56px;
	mask-image: linear-gradient(180deg, rgba(0,0,0,0.6), rgba(0,0,0,0));
	pointer-events: none;
	z-index: 0;
}

.ai4at-hero__inner {
	position: relative;
	z-index: 1;
	display: grid;
	grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
	gap: 64px;
	align-items: center;
	width: 100%;
}

@media (max-width: 960px) {
	.ai4at-hero__inner { grid-template-columns: 1fr; gap: 48px; }
}

.ai4at-hero__eyebrow {
	display: inline-flex;
	align-items: center;
	gap: 8px;
	padding: 6px 12px;
	border-radius: 999px;
	background: var(--ai4at-accent-soft);
	color: var(--ai4at-accent);
	font-size: 13px;
	font-weight: 600;
	margin-bottom: 20px;
}
.ai4at-hero__eyebrow::before {
	content: '';
	width: 8px; height: 8px; border-radius: 50%;
	background: var(--ai4at-accent);
	box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.18);
}

.ai4at-hero__title {
	font-size: clamp(26px, 4vw, 44px);
	line-height: 1.1;
	margin: 0 0 20px;
	letter-spacing: -0.02em;
}
.ai4at-hero__title em {
	font-style: normal;
	color: var(--ai4at-accent);
	background: linear-gradient(135deg, #6366f1, #a855f7);
	-webkit-background-clip: text;
	background-clip: text;
	-webkit-text-fill-color: transparent;
}

.ai4at-hero__lead {
	font-size: clamp(16px, 1.5vw, 19px);
	color: var(--ai4at-text-muted);
	max-width: 540px;
	margin-bottom: 32px;
}

.ai4at-hero__ctas {
	display: flex;
	flex-wrap: wrap;
	gap: 12px;
	margin-bottom: 32px;
}

.ai4at-hero__points {
	list-style: none;
	padding: 0;
	margin: 0;
	display: grid;
	grid-template-columns: repeat(2, minmax(0, 1fr));
	gap: 12px 24px;
	max-width: 540px;
}
.ai4at-hero__points li {
	display: flex;
	align-items: flex-start;
	gap: 10px;
	font-size: 14px;
	color: var(--ai4at-text-muted);
}
.ai4at-hero__points li::before {
	content: '';
	flex-shrink: 0;
	width: 18px; height: 18px;
	border-radius: 50%;
	background: var(--ai4at-accent-soft) url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236366f1' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'><polyline points='20 6 9 17 4 12'/></svg>") no-repeat center;
	margin-top: 2px;
}

.ai4at-hero__demo {
	position: relative;
	background: var(--ai4at-surface);
	border: 1px solid var(--ai4at-border);
	border-radius: var(--ai4at-radius-xl);
	box-shadow: var(--ai4at-shadow-lg);
	min-height: 440px;
	display: flex;
	flex-direction: column;
	overflow: hidden;
}
.ai4at-hero__demo-header {
	padding: 16px 20px;
	border-bottom: 1px solid var(--ai4at-border);
	background: var(--ai4at-surface-2);
	display: flex;
	align-items: center;
	gap: 12px;
}
.ai4at-hero__demo-avatar {
	width: 36px; height: 36px;
	border-radius: 50%;
	background: var(--ai4at-accent);
	color: #fff;
	display: flex; align-items: center; justify-content: center;
	font-weight: 700;
	flex-shrink: 0;
}
.ai4at-hero__demo-avatar--mark {
	background: transparent;
	overflow: hidden;
	padding: 0;
}
.ai4at-hero__demo-avatar-img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	display: block;
	border-radius: 50%;
}
.ai4at-hero__demo-name { font-weight: 600; font-size: 15px; }
.ai4at-hero__demo-status { font-size: 12px; color: var(--ai4at-success); display: flex; align-items: center; gap: 6px; }
.ai4at-hero__demo-status::before {
	content: '';
	width: 7px; height: 7px; border-radius: 50%;
	background: var(--ai4at-success);
}

.ai4at-hero__demo-placeholder {
	flex: 1;
	display: flex;
	align-items: center;
	justify-content: center;
	padding: 32px;
	color: var(--ai4at-text-soft);
	text-align: center;
	font-size: 14px;
}

/* Hero: социальное подтверждение + логотипы моделей */
.ai4at-hero__trust {
	position: relative;
	z-index: 1;
	margin-top: 48px;
	padding-top: 28px;
	border-top: 1px solid rgba(28, 36, 60, 0.08);
	display: grid;
	grid-template-columns: minmax(0, 1.45fr) minmax(0, auto);
	gap: 24px 40px;
	align-items: center;
	width: 100%;
}
.ai4at-hero__trust-stat { min-width: 0; }
.ai4at-hero__trust-line {
	display: flex;
	flex-wrap: wrap;
	align-items: baseline;
	gap: 10px 14px;
	margin: 0 0 6px;
}
.ai4at-hero__trust-number {
	font-size: clamp(28px, 3.8vw, 44px);
	font-weight: 800;
	letter-spacing: -0.03em;
	line-height: 1;
	color: var(--ai4at-text);
	font-variant-numeric: tabular-nums;
}
.ai4at-hero__trust-caption {
	font-size: clamp(15px, 1.35vw, 18px);
	font-weight: 600;
	color: var(--ai4at-text-muted);
}
.ai4at-hero__trust-date {
	margin: 0;
	font-size: 13px;
	color: var(--ai4at-text-muted);
}
.ai4at-hero__trust-logos {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	justify-content: flex-end;
	gap: 18px 26px;
	list-style: none;
	margin: 0;
	padding: 0;
}
.ai4at-hero__trust-logo {
	margin: 0;
	padding: 0;
	display: flex;
	align-items: center;
	justify-content: center;
	min-height: 36px;
}
.ai4at-hero__trust-logo-img {
	display: block;
	max-height: 36px;
	width: auto;
	max-width: min(112px, 24vw);
	height: auto;
	object-fit: contain;
	filter: grayscale(1);
	opacity: 0.7;
	transition: opacity 0.2s ease, filter 0.2s ease;
}
.ai4at-hero__trust-logo-img:hover {
	opacity: 1;
	filter: grayscale(0);
}
@media (max-width: 960px) {
	.ai4at-hero__trust {
		grid-template-columns: 1fr;
		margin-top: 40px;
		padding-top: 24px;
	}
	.ai4at-hero__trust-logos {
		justify-content: flex-start;
	}
}

/* ---------- Section ---------- */
.ai4at-section { padding: 80px 0; }
.ai4at-section--alt { background: var(--ai4at-surface); border-top: 1px solid var(--ai4at-border); border-bottom: 1px solid var(--ai4at-border); }

.ai4at-section__title {
	font-size: clamp(26px, 3vw, 36px);
	text-align: center;
	margin: 0 0 14px;
	letter-spacing: -0.02em;
}
.ai4at-section__lead {
	display: block;
	width: 100%;
	text-align: center;
	color: var(--ai4at-text-muted);
	font-size: 17px;
	max-width: none;
	margin: 0 auto 48px;
	text-wrap: balance;
}

.ai4at-features { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; }

.ai4at-feature {
	background: var(--ai4at-surface);
	border: 1px solid var(--ai4at-border);
	border-radius: var(--ai4at-radius-lg);
	padding: 28px;
	transition: border-color 0.15s, transform 0.15s, box-shadow 0.15s;
}
.ai4at-feature:hover {
	border-color: var(--ai4at-accent);
	transform: translateY(-2px);
	box-shadow: var(--ai4at-shadow);
}
.ai4at-feature__icon {
	width: 44px; height: 44px;
	border-radius: var(--ai4at-radius);
	background: var(--ai4at-accent-soft);
	color: var(--ai4at-accent);
	display: flex; align-items: center; justify-content: center;
	margin-bottom: 16px;
}
.ai4at-feature__title { font-size: 17px; margin-bottom: 8px; }
.ai4at-feature__text { color: var(--ai4at-text-muted); font-size: 14.5px; margin: 0; }

/* ---------- Footer ---------- */
.ai4at-footer {
	padding: 40px 0;
	border-top: 1px solid var(--ai4at-border);
	background: var(--ai4at-surface);
}
.ai4at-footer__inner {
	display: flex;
	flex-wrap: wrap;
	justify-content: space-between;
	gap: 16px;
	align-items: center;
	font-size: 14px;
	color: var(--ai4at-text-muted);
}

/* ---------- Auth pages (login/register/reset) ---------- */
.ai4at-auth {
	min-height: calc(100vh - 64px);
	display: flex;
	align-items: center;
	justify-content: center;
	padding: 60px 24px;
}
.ai4at-auth__card {
	width: 100%;
	max-width: 440px;
	background: var(--ai4at-surface);
	border: 1px solid var(--ai4at-border);
	border-radius: var(--ai4at-radius-xl);
	box-shadow: var(--ai4at-shadow);
	padding: 36px;
}
.ai4at-auth__title { font-size: 24px; margin-bottom: 8px; text-align: center; }
.ai4at-auth__lead { color: var(--ai4at-text-muted); text-align: center; margin-bottom: 28px; font-size: 14.5px; }
.ai4at-auth__alt { text-align: center; margin-top: 20px; font-size: 14px; color: var(--ai4at-text-muted); }

.ai4at-captcha {
	height: 100px;
	margin-bottom: 18px;
}

.ai4at-alert {
	padding: 12px 14px;
	border-radius: var(--ai4at-radius);
	font-size: 14px;
	margin-bottom: 16px;
	border: 1px solid;
}
.ai4at-alert--error { background: #fef2f2; border-color: #fecaca; color: #991b1b; }
.ai4at-alert--success { background: #f0fdf4; border-color: #bbf7d0; color: #166534; }
.ai4at-alert--info { background: var(--ai4at-accent-soft); border-color: #c7d2fe; color: var(--ai4at-accent-hover); }

/* ---------- Form rows ---------- */
.ai4at-row { display: flex; gap: 12px; }
.ai4at-row > * { flex: 1; min-width: 0; }
.ai4at-checkbox {
	display: flex; align-items: flex-start; gap: 10px;
	font-size: 13.5px; color: var(--ai4at-text-muted); line-height: 1.5;
}
.ai4at-checkbox input[type=checkbox] {
	width: 16px; height: 16px;
	accent-color: var(--ai4at-accent);
	margin-top: 2px;
	flex-shrink: 0;
}
.ai4at-link-row { display: flex; justify-content: space-between; align-items: center; gap: 8px; margin: -8px 0 12px; font-size: 13px; }

/* ---------- Utility ---------- */
.ai4at-text-muted { color: var(--ai4at-text-muted); }
.ai4at-text-center { text-align: center; }
.ai4at-mt-0 { margin-top: 0; }
.ai4at-mt-2 { margin-top: 16px; }
.ai4at-mt-4 { margin-top: 32px; }
.ai4at-flex { display: flex; }
.ai4at-flex-between { display: flex; justify-content: space-between; align-items: center; }
.ai4at-gap-2 { gap: 12px; }