/* ==========================================================================
   SSENSOFT Company Website
   Design: Dark Tech (Stripe/Linear/Vercel 계열) - IT 테크 기업 스타일
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Manrope:wght@400;500;600;700;800&family=Noto+Sans+KR:wght@400;500;700;900&family=JetBrains+Mono:wght@400;500;700&display=swap');

:root {
    --color-black: #ffffff;
    --color-white: #ffffff;
    --color-ink: #e7ebf3;
    --color-gray-900: #c4cbdb;
    --color-gray-600: #8891a7;
    --color-gray-300: #262c3d;
    --color-gray-100: #10131d;
    --color-bg: #05070d;
    --color-surface: #0b0f19;
    --color-accent: #4f7dfa;
    --color-accent-2: #8b5cf6;
    --gradient-brand: linear-gradient(120deg, #4f7dfa 0%, #8b5cf6 100%);
    --font-en: 'Manrope', 'Noto Sans KR', sans-serif;
    --font-kr: 'Noto Sans KR', 'Manrope', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --container-w: 1200px;
    --header-h: 84px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; overflow-x: hidden; }

body {
    font-family: var(--font-kr);
    color: var(--color-ink);
    background: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    position: relative;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -2;
    background:
        radial-gradient(circle at 15% 0%, rgba(79, 125, 250, 0.16), transparent 45%),
        radial-gradient(circle at 85% 15%, rgba(139, 92, 246, 0.14), transparent 45%),
        var(--color-bg);
}

body::after {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -1;
    background-image:
        linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
    background-size: 56px 56px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 40%, transparent 100%);
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

.container {
    max-width: var(--container-w);
    margin: 0 auto;
    padding: 0 32px;
}

/* ---------- Header ---------- */
.site-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-h);
    display: flex;
    align-items: center;
    background: rgba(5, 7, 13, 0.72);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    z-index: 1000;
    border-bottom: 1px solid transparent;
    transition: border-color .3s ease, background .3s ease;
}

.site-header.scrolled {
    border-bottom-color: var(--color-gray-300);
    background: rgba(5, 7, 13, 0.92);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
}

.logo {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: 22px;
    letter-spacing: -0.02em;
    color: var(--color-white);
}

.logo span {
    background: var(--gradient-brand);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

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

.main-nav a {
    font-family: var(--font-en);
    font-weight: 600;
    font-size: 15px;
    color: var(--color-gray-600);
    position: relative;
    padding: 6px 0;
    transition: color .2s ease;
}

.main-nav a:hover,
.main-nav a.active { color: var(--color-white); }

.main-nav a.active::after {
    content: '';
    position: absolute;
    left: 0; right: 0; bottom: -2px;
    height: 2px;
    border-radius: 2px;
    background: var(--gradient-brand);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1100;
}

.nav-toggle span {
    display: block;
    height: 2px;
    width: 100%;
    background: var(--color-white);
    border-radius: 2px;
    transition: transform .25s ease, opacity .25s ease;
}

/* ---------- Hero ---------- */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding-top: var(--header-h);
    position: relative;
    overflow: hidden;
}

.hero-eyebrow {
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 13px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.hero-eyebrow::before {
    content: '';
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--gradient-brand);
    box-shadow: 0 0 12px rgba(79, 125, 250, 0.8);
}

.hero h1 {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: clamp(40px, 7vw, 96px);
    line-height: 1.05;
    letter-spacing: -0.03em;
    max-width: 16ch;
    color: var(--color-white);
}

.hero h1 .kr {
    font-family: var(--font-kr);
    background: var(--gradient-brand);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.hero-sub {
    margin-top: 28px;
    font-size: 19px;
    color: var(--color-gray-600);
    max-width: 46ch;
}

.hero-actions {
    margin-top: 44px;
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-stats {
    margin-top: 96px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    border-top: 1px solid var(--color-gray-300);
    padding-top: 32px;
}

.stat-num {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: 36px;
    color: var(--color-white);
}

.hero-visual {
    margin-top: 80px;
    border-radius: 20px;
    overflow: hidden;
    border: 1px solid var(--color-gray-300);
    background: var(--color-surface);
    box-shadow: 0 40px 100px -30px rgba(79, 125, 250, 0.25);
}

.hero-visual svg, .hero-visual img, .hero-img { width: 100%; height: auto; display: block; object-fit: cover; }

.stat-num span {
    background: var(--gradient-brand);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.stat-label {
    margin-top: 6px;
    font-size: 14px;
    color: var(--color-gray-600);
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 15px;
    border-radius: 999px;
    transition: transform .2s ease, background .2s ease, color .2s ease, box-shadow .2s ease;
}

.btn-primary {
    background: var(--gradient-brand);
    color: var(--color-white);
    box-shadow: 0 8px 24px -6px rgba(79, 125, 250, 0.5);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 32px -6px rgba(79, 125, 250, 0.7);
}

.btn-outline {
    border: 1px solid var(--color-gray-300);
    color: var(--color-white);
}

.btn-outline:hover { border-color: var(--color-accent); transform: translateY(-2px); }

/* ---------- Section common ---------- */
section { padding: 140px 0; position: relative; }

.section-head {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 40px;
    margin-bottom: 72px;
}

.section-eyebrow {
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 13px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: 16px;
}

.section-title {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: clamp(32px, 4vw, 52px);
    letter-spacing: -0.02em;
    max-width: 14ch;
    color: var(--color-white);
}

.section-desc {
    max-width: 40ch;
    color: var(--color-gray-600);
    font-size: 16px;
}

.section-alt { background: var(--color-surface); }

/* ---------- Services grid ---------- */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--color-gray-300);
    border: 1px solid var(--color-gray-300);
}

.service-card {
    background: var(--color-bg);
    padding: 48px 40px;
    transition: background .25s ease;
}

.section-alt .service-card { background: var(--color-surface); }

.service-card:hover { background: var(--color-gray-100); }

.service-index {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 13px;
    color: var(--color-accent);
    margin-bottom: 28px;
}

.service-card h3 {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 22px;
    margin-bottom: 14px;
    color: var(--color-white);
}

.service-card p { color: var(--color-gray-600); font-size: 15px; }

.service-tags {
    margin-top: 20px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.service-tags span {
    font-size: 12px;
    font-family: var(--font-mono);
    font-weight: 500;
    padding: 6px 12px;
    border: 1px solid var(--color-gray-300);
    border-radius: 999px;
    color: var(--color-gray-600);
}

/* ---------- Solutions (home preview) ---------- */
.solution-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1px;
    background: var(--color-gray-300);
    border: 1px solid var(--color-gray-300);
}

.solution-card {
    background: var(--color-bg);
    padding: 32px 24px;
    display: flex;
    flex-direction: column;
    gap: 14px;
    transition: background .25s ease;
}

a.solution-card:hover { background: var(--color-gray-100); }

.solution-card h3 {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 18px;
    color: var(--color-white);
}

.solution-card p { color: var(--color-gray-600); font-size: 13px; }

.solution-more {
    margin-top: 32px;
    text-align: right;
}

.solution-more a {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 14px;
    color: var(--color-white);
    border-bottom: 1px solid var(--color-gray-300);
    padding-bottom: 2px;
    transition: color .2s ease, border-color .2s ease;
}

.solution-more a:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
}

/* ---------- Process ---------- */
.process-list { display: flex; flex-direction: column; }

.process-item {
    display: grid;
    grid-template-columns: 100px 1fr 2fr;
    gap: 32px;
    padding: 36px 0;
    border-top: 1px solid var(--color-gray-300);
    align-items: baseline;
}

.process-item:last-child { border-bottom: 1px solid var(--color-gray-300); }

.process-num {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 15px;
    color: var(--color-accent);
}

.process-item h3 {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 22px;
    color: var(--color-white);
}

.process-item p { color: var(--color-gray-600); font-size: 15px; }

/* ---------- Portfolio ---------- */
.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.portfolio-grid .portfolio-card {
    display: flex;
    flex-direction: column;
}

.portfolio-card {
    position: relative;
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    border-radius: 16px;
    padding: 40px;
    overflow: hidden;
    transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}

.portfolio-card:hover {
    transform: translateY(-6px);
    border-color: rgba(79, 125, 250, 0.4);
    box-shadow: 0 24px 48px -12px rgba(79, 125, 250, 0.25);
}

.portfolio-card-head {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 12px;
}

.portfolio-tag {
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 12px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-accent);
}

.store-badges {
    display: flex;
    gap: 6px;
    flex-shrink: 0;
}

.store-badges span {
    font-size: 11px;
    font-family: var(--font-en);
    font-weight: 700;
    padding: 4px 10px;
    border-radius: 999px;
    background: var(--color-gray-300);
    color: var(--color-gray-900);
}

.portfolio-card h3 {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 26px;
    margin: 16px 0 12px;
    color: var(--color-white);
}

.portfolio-card p { color: var(--color-gray-600); font-size: 15px; margin-bottom: 24px; }

.portfolio-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.portfolio-stack span {
    font-size: 12px;
    font-family: var(--font-mono);
    font-weight: 500;
    padding: 5px 10px;
    background: var(--color-gray-100);
    border: 1px solid var(--color-gray-300);
    border-radius: 6px;
    color: var(--color-gray-900);
}

.portfolio-link {
    display: inline-block;
    margin-top: 24px;
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 14px;
    color: var(--color-white);
    border-bottom: 1px solid var(--color-gray-300);
    padding-bottom: 2px;
    transition: color .2s ease, border-color .2s ease;
}

.portfolio-link:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
}

/* ---------- About / Sub-page hero ---------- */
.about-hero {
    padding-top: calc(var(--header-h) + 100px);
    padding-bottom: 100px;
}

.about-hero .container {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 56px;
    align-items: center;
}

.about-hero .container > * {
    min-width: 0;
}

.about-hero h1 {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: clamp(36px, 5.5vw, 68px);
    letter-spacing: -0.02em;
    max-width: 18ch;
    color: var(--color-white);
}

.about-hero p {
    margin-top: 24px;
    font-size: 18px;
    color: var(--color-gray-600);
    max-width: 60ch;
}

.about-hero-visual {
    border-radius: 20px;
    overflow: hidden;
    border: 1px solid var(--color-gray-300);
    background: var(--color-surface);
    box-shadow: 0 40px 100px -30px rgba(139, 92, 246, 0.22);
}

.about-hero-visual svg, .about-hero-visual img { width: 100%; height: auto; display: block; object-fit: cover; }

.value-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.value-grid-4 {
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.value-card h3 {
    font-family: var(--font-en);
    font-weight: 700;
    font-size: 20px;
    margin: 20px 0 12px;
    color: var(--color-white);
}

.value-card p { color: var(--color-gray-600); font-size: 15px; }

.value-num {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 44px;
    color: var(--color-gray-300);
}

/* AI Capabilities Section */
.ai-capabilities-section {
    padding: 100px 0;
}

.ai-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
    margin-top: 48px;
}

.ai-grid > * {
    min-width: 0;
}

.ai-card {
    padding: 36px;
    border-radius: 20px;
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease;
    display: flex;
    flex-direction: column;
}

.ai-card:hover {
    transform: translateY(-6px);
    border-color: rgba(139, 92, 246, 0.4);
    box-shadow: 0 20px 40px -15px rgba(139, 92, 246, 0.25);
}

.ai-card-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 52px;
    height: 52px;
    border-radius: 14px;
    background: rgba(139, 92, 246, 0.12);
    color: #a78bfa;
    margin-bottom: 24px;
}

.ai-card h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-white);
    margin-bottom: 12px;
    line-height: 1.4;
}

.ai-card p {
    font-size: 15px;
    color: var(--color-gray-600);
    line-height: 1.6;
    margin-bottom: 24px;
    flex-grow: 1;
}

.ai-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.ai-tags span {
    font-size: 12px;
    font-family: var(--font-mono);
    font-weight: 500;
    padding: 4px 10px;
    background: rgba(139, 92, 246, 0.08);
    border: 1px solid rgba(139, 92, 246, 0.2);
    border-radius: 6px;
    color: #c4b5fd;
}

.info-table {
    width: 100%;
    table-layout: fixed;
    border-collapse: collapse;
}

.info-table tr { border-top: 1px solid var(--color-gray-300); }
.info-table tr:last-child { border-bottom: 1px solid var(--color-gray-300); }

.info-table th,
.info-table td {
    text-align: left;
    padding: 22px 0;
    font-size: 15px;
    color: var(--color-ink);
    word-break: keep-all;
    overflow-wrap: break-word;
}

.info-table th {
    width: 220px;
    font-family: var(--font-en);
    font-weight: 700;
    color: var(--color-gray-600);
}

/* ---------- Contact Page Enhancements ---------- */
.contact-hero {
    padding-bottom: 60px;
}

.contact-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-top: 32px;
}

.contact-badge-item {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    border-radius: 999px;
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    font-size: 14px;
    font-weight: 500;
    color: var(--color-ink);
}

.badge-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #10b981;
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.6);
}

.badge-dot.blue {
    background: var(--color-accent);
    box-shadow: 0 0 10px rgba(79, 125, 250, 0.6);
}

.contact-section {
    padding-bottom: 120px;
}

.contact-wrap {
    padding-top: 0;
    display: grid;
    grid-template-columns: 1fr 1.1fr;
    gap: 64px;
    align-items: start;
}

/* Left Info Panel */
.contact-info-panel {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.contact-panel-head h2 {
    font-family: var(--font-en);
    font-size: 28px;
    font-weight: 800;
    color: var(--color-white);
    margin-bottom: 8px;
}

.contact-panel-head p {
    color: var(--color-gray-600);
    font-size: 15px;
}

.contact-card-grid {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.contact-card {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 24px;
    border-radius: 16px;
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}

.contact-card:hover {
    transform: translateY(-3px);
    border-color: rgba(79, 125, 250, 0.4);
    box-shadow: 0 12px 30px -10px rgba(79, 125, 250, 0.2);
}

.contact-card-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: 12px;
    background: rgba(79, 125, 250, 0.1);
    color: var(--color-accent);
    flex-shrink: 0;
}

.contact-card-content {
    display: flex;
    flex-direction: column;
}

.contact-card-label {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-accent);
    margin-bottom: 4px;
}

.contact-card-value {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-white);
    line-height: 1.5;
    text-decoration: none;
}

a.contact-card-value:hover {
    color: var(--color-accent);
}

.contact-card-sub {
    font-size: 13px;
    color: var(--color-gray-600);
    margin-top: 4px;
}

.contact-hours-box {
    padding: 20px 24px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.02);
    border: 1px dashed var(--color-gray-300);
}

.hours-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-en);
    font-size: 15px;
    font-weight: 700;
    color: var(--color-white);
    margin-bottom: 8px;
}

.contact-hours-box p {
    font-size: 14px;
    color: var(--color-gray-600);
    line-height: 1.6;
}

/* Right Form Panel */
.contact-form-panel {
    padding: 40px;
    border-radius: 20px;
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    box-shadow: 0 20px 50px -15px rgba(0, 0, 0, 0.5);
}

.form-header h2 {
    font-family: var(--font-en);
    font-size: 26px;
    font-weight: 800;
    color: var(--color-white);
    margin-bottom: 8px;
}

.form-header p {
    color: var(--color-gray-600);
    font-size: 14px;
    margin-bottom: 32px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.form-group { margin-bottom: 24px; }

.form-group label {
    display: block;
    font-weight: 600;
    font-size: 14px;
    margin-bottom: 10px;
    color: var(--color-ink);
}

.form-group label .required {
    color: var(--color-accent);
}

.form-group label .optional {
    font-size: 12px;
    color: var(--color-gray-600);
    font-weight: normal;
}

/* Category Checkbox Tags */
.category-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 8px;
}

.tag-checkbox input {
    display: none;
}

.tag-checkbox span {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 8px;
    background: var(--color-bg);
    border: 1px solid var(--color-gray-300);
    color: var(--color-gray-600);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all .2s ease;
}

.tag-checkbox input:checked + span {
    background: rgba(79, 125, 250, 0.15);
    border-color: var(--color-accent);
    color: var(--color-white);
    font-weight: 600;
}

.tag-checkbox span:hover {
    border-color: var(--color-gray-600);
    color: var(--color-white);
}

.form-group input,
.form-group textarea {
    width: 100%;
    border: 1px solid var(--color-gray-300);
    border-radius: 12px;
    background: var(--color-bg);
    padding: 14px 18px;
    font-size: 15px;
    font-family: var(--font-kr);
    color: var(--color-ink);
    transition: border-color .2s ease, box-shadow .2s ease;
}

.form-group input::placeholder,
.form-group textarea::placeholder { color: var(--color-gray-600); }

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(79, 125, 250, 0.2);
}

.form-group textarea { resize: vertical; min-height: 140px; }

.btn-submit-custom {
    width: 100%;
    padding: 16px 24px;
    font-size: 16px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.form-error {
    color: #ff6b81;
    font-size: 13px;
    margin-top: 6px;
    display: none;
}

.form-group.invalid .form-error { display: block; }
.form-group.invalid input,
.form-group.invalid textarea { border-color: #ff6b81; }

/* FAQ Section */
.faq-section {
    padding: 100px 0;
}

.faq-list {
    max-width: 800px;
    margin: 48px auto 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.faq-item {
    border: 1px solid var(--color-gray-300);
    border-radius: 14px;
    background: var(--color-surface);
    overflow: hidden;
    transition: border-color .2s ease;
}

.faq-item.active {
    border-color: var(--color-accent);
}

.faq-question {
    padding: 24px 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}

.faq-question h3 {
    font-size: 17px;
    font-weight: 700;
    color: var(--color-white);
    line-height: 1.4;
}

.faq-icon {
    font-size: 22px;
    font-weight: 400;
    color: var(--color-accent);
    transition: transform .3s ease;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 28px 24px;
    display: none;
    font-size: 15px;
    color: var(--color-gray-600);
    line-height: 1.7;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding-top: 16px;
}

.faq-item.active .faq-answer {
    display: block;
}

/* ---------- CTA ---------- */
.cta {
    background: linear-gradient(135deg, #0b0f19 0%, #131a2c 50%, #191140 100%);
    color: var(--color-white);
    text-align: center;
    padding: 140px 0;
    position: relative;
    overflow: hidden;
    border-top: 1px solid var(--color-gray-300);
    border-bottom: 1px solid var(--color-gray-300);
}

.cta::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 0%, rgba(79, 125, 250, 0.25), transparent 55%);
    pointer-events: none;
}

.cta .container { position: relative; }

.cta h2 {
    font-family: var(--font-en);
    font-weight: 800;
    font-size: clamp(30px, 4.5vw, 52px);
    letter-spacing: -0.02em;
    margin-bottom: 32px;
}

.cta .btn-primary:hover { transform: translateY(-2px); }

/* ---------- Footer ---------- */
.site-footer {
    background: var(--color-surface);
    border-top: 1px solid var(--color-gray-300);
    padding-top: 96px;
}

.footer-inner {
    display: grid;
    grid-template-columns: 1.6fr 1fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 64px;
}

.footer-brand p { margin-top: 16px; color: var(--color-gray-600); font-size: 14px; }

.footer-col h4 {
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 20px;
    color: var(--color-gray-600);
}

.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col li { font-size: 14px; color: var(--color-gray-600); }
.footer-col a:hover { color: var(--color-accent); }

.footer-bottom {
    border-top: 1px solid var(--color-gray-300);
    padding: 24px 0;
}

.footer-bottom span {
    font-size: 13px;
    color: var(--color-gray-600);
    font-family: var(--font-en);
}

/* ---------- Layer popup (alert 대체) ---------- */
.layer-popup {
    position: fixed;
    inset: 0;
    background: rgba(2, 4, 9, 0.72);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

.layer-popup-box {
    background: var(--color-surface);
    border: 1px solid var(--color-gray-300);
    border-radius: 16px;
    padding: 40px;
    width: min(420px, 90vw);
    text-align: center;
    box-shadow: 0 24px 60px rgba(0,0,0,0.5);
}

.layer-popup-box p {
    font-size: 16px;
    margin-bottom: 28px;
    white-space: pre-line;
    color: var(--color-ink);
}

/* ---------- Reveal animation ---------- */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity .7s ease, transform .7s ease;
}

.reveal.in-view { opacity: 1; transform: translateY(0); }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
    .main-nav {
        display: none;
        position: fixed;
        top: 0;
        left: 0; 
        right: 0;
        bottom: 0;
        height: 100vh;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 20px;
        background: rgba(11, 15, 25, 0.98);
        backdrop-filter: blur(12px);
        z-index: 1050;
        padding-top: var(--header-h);
    }

    .main-nav.open { display: flex; }

    .main-nav a {
        font-size: 24px;
        font-weight: 700;
        color: var(--color-gray-600);
        padding: 12px 0;
        border: none;
    }

    .main-nav a.active, .main-nav a:hover {
        color: var(--color-accent);
    }

    .nav-toggle { display: flex !important; }
    .nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
    .nav-toggle.active span:nth-child(2) { opacity: 0; }
    .nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

    .hero-stats { grid-template-columns: repeat(2, 1fr); }
    .about-hero .container { grid-template-columns: 1fr; }
    .about-hero-visual { max-width: 420px; }
    .services-grid { grid-template-columns: 1fr; }
    .value-grid, .value-grid-4 { grid-template-columns: 1fr; gap: 48px; }
    .ai-grid { grid-template-columns: 1fr; }
    .portfolio-grid { grid-template-columns: repeat(2, 1fr); }
    .solution-grid { grid-template-columns: repeat(2, 1fr); }
    .process-item { grid-template-columns: 1fr; gap: 8px; }
    .contact-wrap { grid-template-columns: 1fr; gap: 56px; }
    .footer-inner { grid-template-columns: 1fr 1fr; }
    section { padding: 88px 0; }
}

@media (max-width: 560px) {
    .container { padding: 0 20px; }
    .footer-inner { grid-template-columns: 1fr; }
    .section-head { flex-direction: column; align-items: flex-start; }
    .portfolio-grid { grid-template-columns: 1fr; }
    .solution-grid { grid-template-columns: 1fr; }
    .info-table th { width: 100px; }
}