/* ============================================
   DOSANG - SAP Consulting Corporate Website
   Professional / Enterprise Design
   ============================================ */

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

:root {
    --primary: #1a3a5c;
    --primary-dark: #0f2440;
    --accent: #2e7dd1;
    --accent-light: #4a9ae8;
    --text: #1a1a2e;
    --text-light: #5a6270;
    --text-muted: #8a919c;
    --bg: #ffffff;
    --bg-subtle: #f5f7fa;
    --bg-dark: #0c1926;
    --border: #e2e6ec;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 6px 16px rgba(0,0,0,0.04);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.08), 0 16px 40px rgba(0,0,0,0.06);
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

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

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

/* --- Container --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- Section --- */
.section {
    padding: 120px 0;
}

.section-header {
    margin-bottom: 64px;
}

.section-label {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--accent);
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 900;
    line-height: 1.3;
    color: var(--primary-dark);
}

.section-desc {
    font-size: 1.05rem;
    color: var(--text-light);
    margin-top: 16px;
    max-width: 560px;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    transition: all var(--transition);
    cursor: pointer;
    border: none;
    font-family: inherit;
}

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

.btn-primary:hover {
    background: var(--accent-light);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(46, 125, 209, 0.3);
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 1.5px solid rgba(255,255,255,0.4);
}

.btn-outline:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.7);
}

.btn-full {
    width: 100%;
}

/* ============================================
   HEADER / NAV
   ============================================ */
#header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transition: all var(--transition);
}

#header.scrolled {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
}

.logo-img {
    height: 48px;
    width: auto;
    filter: brightness(0) invert(1);
    transition: filter var(--transition);
}

#header.scrolled .logo-img {
    filter: none;
}

.logo-text {
    font-size: 1.4rem;
    font-weight: 900;
    letter-spacing: 2px;
    color: #fff;
    transition: color var(--transition);
}

#header.scrolled .logo-text {
    color: var(--primary-dark);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: rgba(255,255,255,0.8);
    position: relative;
    padding: 4px 0;
    transition: color var(--transition);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width var(--transition);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

#header.scrolled .nav-links a {
    color: var(--text);
}

#header.scrolled .nav-links a:hover {
    color: var(--accent);
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: #fff;
    transition: all var(--transition);
}

#header.scrolled .mobile-toggle span {
    background: var(--text);
}

/* ============================================
   HERO
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(160deg, #0c1926 0%, #1a3a5c 40%, #1e4d7a 70%, #0f2440 100%);
    z-index: 0;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -30%;
    width: 80%;
    height: 160%;
    background: radial-gradient(ellipse, rgba(46,125,209,0.12) 0%, transparent 70%);
}

.hero-bg::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 200px;
    background: linear-gradient(to top, rgba(12,25,38,0.5), transparent);
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    padding: 0 24px;
}

.hero-logo {
    width: 140px;
    height: auto;
    margin: 0 auto 32px;
    filter: brightness(0) invert(1);
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.8s ease forwards 0.1s;
}

.hero-label {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 4px;
    text-transform: uppercase;
    color: var(--accent-light);
    margin-bottom: 24px;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.8s ease forwards 0.3s;
}

.hero-title {
    font-size: clamp(2.4rem, 6vw, 4rem);
    font-weight: 900;
    line-height: 1.25;
    color: #fff;
    margin-bottom: 24px;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.8s ease forwards 0.5s;
}

.text-accent {
    background: linear-gradient(135deg, var(--accent-light), #6cb4f0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.05rem;
    line-height: 1.8;
    color: rgba(255,255,255,0.65);
    margin-bottom: 40px;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.8s ease forwards 0.7s;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.8s ease forwards 0.9s;
}

.hero-scroll {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    opacity: 0;
    animation: fadeUp 0.8s ease forwards 1.2s;
}

.hero-scroll span {
    font-size: 0.7rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: rgba(255,255,255,0.35);
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, rgba(255,255,255,0.3), transparent);
    animation: scrollPulse 2s ease infinite;
}

@keyframes fadeUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes scrollPulse {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.8; }
}

/* ============================================
   ABOUT
   ============================================ */
.about {
    background: var(--bg);
}

/* Philosophy */
.philosophy {
    text-align: center;
    margin-bottom: 72px;
    padding: 48px 32px;
    background: var(--bg-subtle);
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.philosophy-quote {
    font-size: clamp(1.2rem, 2.5vw, 1.6rem);
    font-weight: 800;
    color: var(--primary-dark);
    letter-spacing: 0.5px;
    line-height: 1.5;
    margin-bottom: 16px;
}

.philosophy-desc {
    font-size: 0.95rem;
    color: var(--text-light);
    line-height: 1.8;
}

.philosophy-desc br {
    display: block;
}

/* Team Highlight */
.team-highlight {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    margin-top: 64px;
    padding: 36px 40px;
    background: linear-gradient(135deg, rgba(46,125,209,0.06), rgba(46,125,209,0.02));
    border: 1px solid rgba(46,125,209,0.15);
    border-radius: var(--radius);
}

.team-badge {
    width: 56px;
    height: 56px;
    min-width: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(46,125,209,0.1);
    border-radius: var(--radius-sm);
    color: var(--accent);
}

.team-text h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 8px;
}

.team-text p {
    font-size: 0.95rem;
    color: var(--text-light);
    line-height: 1.7;
}

.team-text strong {
    color: var(--primary-dark);
    font-weight: 700;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.about-text p {
    font-size: 1.05rem;
    color: var(--text-light);
    line-height: 1.9;
    margin-bottom: 20px;
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.stat-item {
    text-align: center;
    padding: 28px 16px;
    border-radius: var(--radius);
    background: var(--bg-subtle);
    border: 1px solid var(--border);
    transition: all var(--transition);
}

.stat-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent);
}

.stat-number {
    font-size: 2.4rem;
    font-weight: 900;
    color: var(--accent);
    display: inline;
}

.stat-suffix {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 4px;
    font-weight: 500;
}

/* ============================================
   SERVICES
   ============================================ */
.services {
    background: var(--bg-subtle);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.service-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px 36px;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 0;
    background: var(--accent);
    transition: height var(--transition);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent);
}

.service-card:hover::before {
    height: 100%;
}

.service-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(46, 125, 209, 0.08);
    border-radius: var(--radius-sm);
    margin-bottom: 24px;
    color: var(--accent);
}

.service-icon svg {
    width: 28px;
    height: 28px;
}

.service-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 12px;
}

.service-desc {
    font-size: 0.92rem;
    color: var(--text-light);
    line-height: 1.7;
}

/* ============================================
   SOLUTIONS
   ============================================ */
.solutions {
    background: var(--bg);
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.solution-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 44px 40px;
    position: relative;
    overflow: hidden;
    transition: all var(--transition);
}

.solution-card-full {
    grid-column: 1 / -1;
}

.solution-card::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), var(--accent-light));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition);
}

.solution-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent);
}

.solution-card:hover::after {
    transform: scaleX(1);
}

.solution-badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: #fff;
    background: var(--accent);
    padding: 5px 14px;
    border-radius: 20px;
    margin-bottom: 20px;
}

.solution-title {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--primary-dark);
    line-height: 1.4;
    margin-bottom: 4px;
}

.solution-abbr {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.solution-desc {
    font-size: 0.92rem;
    color: var(--text-light);
    line-height: 1.75;
    margin-bottom: 20px;
}

.solution-features {
    list-style: none;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.solution-features li {
    font-size: 0.85rem;
    color: var(--text);
    font-weight: 500;
    padding-left: 20px;
    position: relative;
}

.solution-features li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 7px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent);
    opacity: 0.6;
}

/* ============================================
   EXPERTISE
   ============================================ */
.expertise {
    background: var(--bg);
}

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

.expertise-item {
    padding: 32px 28px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: all var(--transition);
    text-align: center;
}

.expertise-item:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: var(--shadow);
}

.expertise-tag {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--accent);
    background: rgba(46, 125, 209, 0.08);
    padding: 4px 12px;
    border-radius: 20px;
    margin-bottom: 16px;
}

.expertise-item h4 {
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--primary-dark);
    margin-bottom: 8px;
}

.expertise-item p {
    font-size: 0.88rem;
    color: var(--text-muted);
}

/* ============================================
   CONTACT
   ============================================ */
.contact {
    background: var(--bg-subtle);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 36px;
    padding-top: 8px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
}

.contact-icon {
    width: 48px;
    height: 48px;
    min-width: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(46, 125, 209, 0.08);
    border-radius: var(--radius-sm);
    color: var(--accent);
}

.contact-icon svg {
    width: 22px;
    height: 22px;
}

.contact-item h4 {
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.contact-item a,
.contact-item p {
    font-size: 1rem;
    color: var(--text);
    font-weight: 500;
}

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

/* Contact Form */
.contact-form {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 14px 18px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-family: inherit;
    color: var(--text);
    background: var(--bg);
    transition: all var(--transition);
    outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(46, 125, 209, 0.1);
}

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

.form-group select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2 4l4 4 4-4' stroke='%238a919c' stroke-width='1.5' fill='none'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
    cursor: pointer;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* File Upload */
.file-upload-label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
    padding: 16px 18px;
    border: 2px dashed var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.92rem;
    font-family: inherit;
    color: var(--text-muted);
    background: var(--bg);
    cursor: pointer;
    transition: all var(--transition);
}

.file-upload-label:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(46, 125, 209, 0.04);
}

.file-upload-label.has-file {
    border-color: var(--accent);
    color: var(--accent);
    border-style: solid;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    background: var(--bg-dark);
    padding: 48px 0 32px;
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-bottom: 32px;
    border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-logo-img {
    height: 48px;
    width: auto;
    filter: brightness(0) invert(1);
}

.footer-brand .logo-text {
    font-size: 1.2rem;
    color: #fff;
}

.footer-brand p {
    font-size: 0.82rem;
    color: rgba(255,255,255,0.4);
    margin-top: 4px;
}

.footer-links {
    display: flex;
    gap: 32px;
}

.footer-links a {
    font-size: 0.85rem;
    color: rgba(255,255,255,0.5);
    transition: color var(--transition);
}

.footer-links a:hover {
    color: #fff;
}

.footer-bottom {
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.3);
}

/* ============================================
   SCROLL ANIMATIONS
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 1024px) {
    .section {
        padding: 80px 0;
    }

    .about-grid {
        gap: 48px;
    }

    .services-grid {
        gap: 24px;
    }

    .contact-grid {
        gap: 48px;
    }
}

@media (max-width: 768px) {
    .mobile-toggle {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--bg);
        flex-direction: column;
        padding: 100px 40px 40px;
        gap: 24px;
        transition: right var(--transition);
        box-shadow: -8px 0 32px rgba(0,0,0,0.1);
    }

    .nav-links.open {
        right: 0;
    }

    .nav-links a {
        color: var(--text) !important;
        font-size: 1.05rem;
    }

    .hero-title {
        font-size: clamp(2rem, 7vw, 3rem);
    }

    .hero-desc br {
        display: none;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .philosophy {
        padding: 32px 24px;
        margin-bottom: 48px;
    }

    .philosophy-desc br {
        display: none;
    }

    .team-highlight {
        flex-direction: column;
        padding: 28px 24px;
        margin-top: 48px;
    }

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

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

    .solution-card {
        padding: 32px 24px;
    }

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

    .contact-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .footer-content {
        flex-direction: column;
        gap: 24px;
        text-align: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }

    .section-header {
        margin-bottom: 48px;
    }

    .section-title br {
        display: none;
    }
}

@media (max-width: 480px) {
    .section {
        padding: 64px 0;
    }

    .about-stats {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }

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

    .stat-number {
        font-size: 2rem;
    }

    .service-card {
        padding: 28px 24px;
    }
}