/* ============================================
   BizSignal — style.css
   Notion-inspired minimal design
   ============================================ */

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --text: #37352F;
    --text-secondary: #6B6B6B;
    --text-light: #9B9B9B;
    --bg: #FFFFFF;
    --bg-gray: #F7F6F3;
    --border: #E5E5E5;
    --accent: #37352F;
    --cta: #EB5757;
    --cta-hover: #D94444;
    --radius: 8px;
    --max-width: 960px;
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

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

body {
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.65;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--text);
    text-decoration: none;
}

ul, ol {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

/* --- Container --- */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

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

.section:last-of-type {
    border-bottom: none;
}

.section-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 48px;
    letter-spacing: -0.02em;
}

/* --- Navigation --- */
.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
}

.nav-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
}

.nav-logo {
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    font-size: 14px;
    color: var(--text-secondary);
    transition: color 0.15s;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text);
}

/* Burger */
.burger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 28px;
    height: 28px;
    cursor: pointer;
    background: none;
    border: none;
    padding: 0;
}

.burger span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text);
    border-radius: 1px;
    transition: transform 0.2s, opacity 0.2s;
}

.burger.open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.burger.open span:nth-child(2) {
    opacity: 0;
}

.burger.open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* Mobile menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: 56px;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg);
    z-index: 99;
    padding: 32px 24px;
}

.mobile-menu.open {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.mobile-menu a {
    font-size: 20px;
    color: var(--text);
    font-weight: 500;
}

/* --- Hero --- */
.hero {
    padding: 100px 0 80px;
    text-align: center;
    border-bottom: 1px solid var(--border);
}

.hero-badge {
    display: inline-block;
    font-size: 13px;
    color: var(--text-secondary);
    background: var(--bg-gray);
    padding: 6px 16px;
    border-radius: 20px;
    margin-bottom: 24px;
    letter-spacing: 0.01em;
}

.hero h1 {
    font-size: 48px;
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.03em;
    color: var(--text);
    margin-bottom: 20px;
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
}

.hero p {
    font-size: 18px;
    line-height: 1.6;
    color: var(--text-secondary);
    max-width: 520px;
    margin: 0 auto 36px;
}

/* Hero short (about, faq) */
.hero-short {
    padding: 64px 0 48px;
    text-align: center;
    border-bottom: 1px solid var(--border);
}

.hero-short h1 {
    font-size: 40px;
    font-weight: 700;
    letter-spacing: -0.03em;
    color: var(--text);
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    font-family: var(--font);
    font-size: 15px;
    font-weight: 500;
    padding: 12px 28px;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
    border: none;
    text-decoration: none;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
}

.btn-primary:hover {
    background: #2C2A25;
}

.btn-cta {
    background: var(--cta);
    color: #fff;
}

.btn-cta:hover {
    background: var(--cta-hover);
}

.btn-outline {
    background: transparent;
    color: var(--text);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    background: var(--bg-gray);
}

/* --- Services (vertical list) --- */
.services-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.service-item {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    padding: 28px 0;
    border-bottom: 1px solid var(--border);
}

.service-item:first-child {
    padding-top: 0;
}

.service-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.service-icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-gray);
    border-radius: var(--radius);
    color: var(--text);
    font-size: 18px;
}

.service-content h3 {
    font-size: 17px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 4px;
    letter-spacing: -0.01em;
}

.service-content p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.55;
}

/* --- Cases (stacked cards) --- */
.cases-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.case-card {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    background: var(--bg);
}

.case-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
    flex-wrap: wrap;
    gap: 8px;
}

.case-name {
    font-size: 17px;
    font-weight: 600;
    color: var(--text);
}

.case-city {
    font-size: 13px;
    color: var(--text-light);
    background: var(--bg-gray);
    padding: 3px 10px;
    border-radius: 12px;
}

.case-task {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.case-results {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.case-result {
    font-size: 14px;
    color: var(--text);
}

.case-result strong {
    display: block;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 2px;
}

.case-result span {
    color: var(--text-secondary);
    font-size: 13px;
}

/* --- Stats --- */
.stats {
    padding: 56px 0;
    border-bottom: 1px solid var(--border);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
    text-align: center;
}

.stat-item strong {
    display: block;
    font-size: 32px;
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.02em;
    margin-bottom: 4px;
}

.stat-item span {
    font-size: 14px;
    color: var(--text-secondary);
}

/* --- CTA Section --- */
.cta-section {
    background: var(--bg-gray);
    padding: 64px 0;
    text-align: center;
    border-bottom: none;
}

.cta-section h2 {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text);
    margin-bottom: 16px;
}

.cta-contacts {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
    margin-bottom: 28px;
    flex-wrap: wrap;
}

.cta-contacts a {
    font-size: 15px;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 6px;
    transition: color 0.15s;
}

.cta-contacts a:hover {
    color: var(--text);
}

/* --- Footer --- */
.footer {
    padding: 48px 0 32px;
    border-top: 1px solid var(--border);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 32px;
    margin-bottom: 40px;
}

.footer-col h4 {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 16px;
}

.footer-col a,
.footer-col p {
    display: block;
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
    transition: color 0.15s;
}

.footer-col a:hover {
    color: var(--text);
}

.footer-bottom {
    font-size: 13px;
    color: var(--text-light);
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

/* --- About page --- */
.about-text {
    max-width: 680px;
}

.about-text p {
    font-size: 16px;
    line-height: 1.75;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.about-text p:last-child {
    margin-bottom: 0;
}

/* Team */
.team-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.team-card {
    text-align: center;
}

.team-avatar {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: var(--bg-gray);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 22px;
    font-weight: 600;
    color: var(--text);
    letter-spacing: -0.02em;
}

.team-card h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 2px;
}

.team-card .team-role {
    font-size: 14px;
    color: var(--text-light);
    margin-bottom: 10px;
}

.team-card .team-bio {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.55;
}

/* Why Us — numbered list */
.reasons-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.reason-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    padding: 24px 0;
    border-bottom: 1px solid var(--border);
}

.reason-item:first-child {
    padding-top: 0;
}

.reason-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.reason-number {
    flex-shrink: 0;
    font-size: 28px;
    font-weight: 700;
    color: var(--text-light);
    line-height: 1;
    min-width: 36px;
    letter-spacing: -0.02em;
}

.reason-content h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 4px;
}

.reason-content p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.55;
}

/* Process — vertical timeline */
.process-timeline {
    position: relative;
    padding-left: 48px;
}

.process-timeline::before {
    content: '';
    position: absolute;
    left: 15px;
    top: 8px;
    bottom: 8px;
    width: 1px;
    background: var(--border);
}

.process-step {
    position: relative;
    padding-bottom: 40px;
}

.process-step:last-child {
    padding-bottom: 0;
}

.process-dot {
    position: absolute;
    left: -48px;
    top: 2px;
    width: 31px;
    height: 31px;
    border-radius: 50%;
    background: var(--bg);
    border: 2px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 700;
    color: var(--text);
}

.process-step h3 {
    font-size: 17px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 6px;
}

.process-step p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.55;
}

/* --- FAQ page --- */
.faq-list {
    max-width: 720px;
}

.faq-list details {
    border-bottom: 1px solid var(--border);
}

.faq-list details:first-child {
    border-top: 1px solid var(--border);
}

.faq-list summary {
    padding: 20px 32px 20px 0;
    font-size: 16px;
    font-weight: 500;
    color: var(--text);
    cursor: pointer;
    position: relative;
    list-style: none;
    line-height: 1.45;
}

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

.faq-list summary::after {
    content: '+';
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    font-size: 20px;
    font-weight: 300;
    color: var(--text-light);
    transition: transform 0.15s;
}

.faq-list details[open] summary::after {
    content: '\2212';
}

.faq-list details p {
    padding: 0 0 20px;
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* ============================================
   Responsive
   ============================================ */

/* 1024px */
@media (max-width: 1024px) {
    .hero h1 {
        font-size: 40px;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 24px;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

/* 768px */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .burger {
        display: flex;
    }

    .hero {
        padding: 72px 0 56px;
    }

    .hero h1 {
        font-size: 34px;
    }

    .hero p {
        font-size: 16px;
    }

    .hero-short {
        padding: 48px 0 36px;
    }

    .hero-short h1 {
        font-size: 32px;
    }

    .section {
        padding: 56px 0;
    }

    .section-title {
        font-size: 24px;
        margin-bottom: 36px;
    }

    .case-results {
        gap: 16px;
    }

    .team-grid {
        grid-template-columns: 1fr;
        gap: 28px;
        max-width: 320px;
    }

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

    .cta-section {
        padding: 48px 0;
    }

    .cta-section h2 {
        font-size: 24px;
    }
}

/* 480px */
@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero {
        padding: 56px 0 40px;
    }

    .hero h1 {
        font-size: 28px;
    }

    .hero p {
        font-size: 15px;
    }

    .hero-short h1 {
        font-size: 26px;
    }

    .section {
        padding: 40px 0;
    }

    .section-title {
        font-size: 22px;
        margin-bottom: 28px;
    }

    .service-item {
        flex-direction: column;
        gap: 12px;
        padding: 20px 0;
    }

    .case-card {
        padding: 20px;
    }

    .case-results {
        flex-direction: column;
        gap: 12px;
    }

    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 20px;
    }

    .stat-item strong {
        font-size: 26px;
    }

    .btn {
        padding: 11px 22px;
        font-size: 14px;
    }

    .reason-item {
        gap: 14px;
    }

    .reason-number {
        font-size: 24px;
        min-width: 28px;
    }

    .process-timeline {
        padding-left: 40px;
    }

    .process-dot {
        left: -40px;
        width: 27px;
        height: 27px;
        font-size: 11px;
    }

    .process-timeline::before {
        left: 13px;
    }

    .faq-list summary {
        font-size: 15px;
        padding: 16px 28px 16px 0;
    }

    .faq-list details p {
        font-size: 14px;
    }
}