/* ========== 1. CSS Variables ========== */
:root {
    /* Colors */
    --primary-blue: #155dfc;
    --text-dark: #101828;
    --text-gray: #6a7282;
    --light-blue: #eff6ff;
    --border-gray: #e5e7eb;
    --white: #ffffff;

    /* Typography */
    --font-family: 'Arimo', 'Noto Sans KR', sans-serif;
    --heading-1-size: 48px;
    --heading-1-weight: 700;
    --heading-1-line-height: 60px;
    --heading-2-size: 36px;
    --heading-2-weight: 700;
    --heading-2-line-height: 40px;
    --heading-3-size: 20px;
    --heading-3-weight: 700;
    --heading-3-line-height: 28px;
    --paragraph-size: 16px;
    --paragraph-weight: 400;
    --paragraph-line-height: 26px;

    /* Spacing */
    --section-gap: 64px;
    --container-padding: 32px;

    /* Border & Shadow */
    --border-radius-button: 8px;
    --border-radius-card: 14px;
    --card-shadow: 0px 20px 25px -5px rgba(0, 0, 0, 0.1), 0px 8px 10px -6px rgba(0, 0, 0, 0.1);
    --image-shadow: 0px 25px 50px -12px rgba(0, 0, 0, 0.25), 0px 10px 20px -8px rgba(0, 0, 0, 0.1);
}

/* ========== 2. Reset & Base ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body.signature-intro-page {
    font-family: var(--font-family);
    color: var(--text-dark);
    line-height: 1.6;
    overflow-x: hidden;
    background: var(--white);
}

/* ========== 3. Container ========== */
.container {
    max-width: 1328px;
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* ========== 4. PC Styles (Default, 1024px+) ========== */

/* Header */
.intro-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 0.667px solid var(--border-gray);
    height: 64.667px;
    padding: 0 56px;
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    height: 32px;
    width: auto;
}

.header-nav {
    display: flex;
    gap: 16px;
    align-items: center;
}

.btn-login,
.btn-logout {
    background: var(--white);
    border: 0.667px solid var(--border-gray);
    border-radius: var(--border-radius-button);
    padding: 0px 12.667px;
    height: 32px;
    line-height: 32px;
    font-size: 14px;
    color: var(--text-dark);
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-start,
.btn-dashboard {
    background: var(--primary-blue);
    border: none;
    border-radius: var(--border-radius-button);
    padding: 0 12px;
    height: 32px;
    line-height: 32px;
    font-size: 14px;
    color: var(--white);
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

/* Hero Section */
.hero-section {
    min-height: 546px;
    padding: 128px 0;
    background: linear-gradient(157.65deg, rgba(239, 246, 255, 0.3) 0%, rgba(0, 0, 0, 0) 50%);
}

.hero-container {
    display: flex;
    gap: 64px;
    align-items: center;
}

.hero-text {
    flex: 1;
}

.badge {
    background: var(--light-blue);
    border: 0.667px solid rgba(21, 93, 252, 0.2);
    border-radius: 8px;
    padding: 2.33px 8px;
    font-size: 12px;
    color: var(--primary-blue);
    display: inline-block;
    margin-bottom: 32px;
}

.hero-title {
    font-size: var(--heading-1-size);
    font-weight: var(--heading-1-weight);
    line-height: var(--heading-1-line-height);
    color: var(--text-dark);
    margin-bottom: 16px;
}

.text-primary {
    color: var(--primary-blue);
}

.hero-subtitle {
    font-size: 18.667px;
    line-height: 26.133px;
    color: var(--text-gray);
    margin-bottom: 32px;
}

.btn-primary {
    background: var(--primary-blue);
    border: none;
    border-radius: var(--border-radius-button);
    padding: 10.17px 24px;
    height: 40px;
    font-size: 14px;
    color: var(--white);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary:hover {
    background: #0d4acc;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(21, 93, 252, 0.3);
}

.icon-arrow {
    width: 16px;
    height: 16px;
    filter: brightness(0) invert(1);
}

.hero-image {
    flex: 1;
    position: relative;
}

.image-glow {
    position: absolute;
    width: 100%;
    height: 100%;
    filter: blur(64px);
    background: linear-gradient(25.52deg, rgba(21, 93, 252, 0.2) 0%, rgba(239, 246, 255, 0.4) 100%);
    z-index: 0;
}

.dashboard-image {
    position: relative;
    z-index: 1;
    width: 100%;
    height: auto;
}

/* Promo Section */
.promo-section {
    min-height: 681px;
    padding: 80px 0;
    background: linear-gradient(152.84deg, #155dfc 0%, rgba(21, 93, 252, 0.8) 100%);
}

.promo-container {
    display: flex;
    flex-direction: column;
    gap: 48px;
    align-items: center;
}

.promo-header {
    text-align: center;
}

.promo-badge {
    background: rgba(255, 255, 255, 0.2);
    border: 0.667px solid rgba(255, 255, 255, 0.3);
    border-radius: 8px;
    padding: 2.33px 16px;
    font-size: 12px;
    color: var(--white);
    display: inline-block;
    margin-bottom: 24px;
}

.promo-title {
    font-size: 48px;
    font-weight: 700;
    line-height: 48px;
    color: var(--white);
    margin-bottom: 24px;
}

.promo-subtitle {
    font-size: 20px;
    line-height: 28px;
    color: rgba(255, 255, 255, 0.9);
}

.promo-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    width: 100%;
}

.promo-card {
    background: rgba(255, 255, 255, 0.1);
    border: 0.667px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius-card);
    padding: 32px;
}

.promo-icon {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 32px;
}

.promo-card-title {
    font-size: 24px;
    font-weight: 700;
    line-height: 32px;
    color: var(--white);
    margin-bottom: 16px;
}

.promo-card-text {
    font-size: 16px;
    line-height: 24px;
    color: rgba(255, 255, 255, 0.9);
}

.promo-cta {
    margin-top: 12px;
}

.btn-white {
    background: var(--white);
    border: none;
    border-radius: var(--border-radius-button);
    padding: 10.17px 24px;
    height: 40px;
    font-size: 14px;
    color: var(--primary-blue);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-white:hover {
    background: #f0f4ff;
    transform: translateY(-2px);
}

.promo-features {
    display: flex;
    gap: 24px;
    justify-content: center;
    flex-wrap: wrap;
}

.promo-feature {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.9);
}

/* Why Section */
.why-section {
    padding: 64px 0;
    background: rgba(239, 246, 255, 0.2);
}

.section-title {
    font-size: var(--heading-2-size);
    font-weight: var(--heading-2-weight);
    line-height: var(--heading-2-line-height);
    text-align: center;
    color: var(--text-dark);
    margin-bottom: 64px;
}

.why-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.why-card {
    background: var(--white);
    border: 0.667px solid var(--border-gray);
    border-radius: var(--border-radius-card);
    padding: 32px;
    box-shadow: var(--card-shadow);
}

.why-icon {
    background: var(--light-blue);
    border-radius: var(--border-radius-card);
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
}

.why-card-title {
    font-size: var(--heading-3-size);
    font-weight: var(--heading-3-weight);
    line-height: var(--heading-3-line-height);
    color: var(--text-dark);
    margin-bottom: 16px;
}

.why-card-text {
    font-size: var(--paragraph-size);
    line-height: var(--paragraph-line-height);
    color: var(--text-gray);
}

/* Features Section */
.features-section {
    padding: 64px 0;
    background: rgba(239, 246, 255, 0.2);
}

.features-content {
    display: flex;
    gap: 48px;
    margin-bottom: 64px;
}

.features-list {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding-top: 27px;
}

.feature-item {
    display: flex;
    gap: 16px;
}

.feature-icon {
    width: 40px;
    height: 40px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon img {
    width: 40px;
    height: 40px;
}

.feature-text {
    flex: 1;
}

.feature-title {
    font-size: var(--heading-3-size);
    font-weight: var(--heading-3-weight);
    line-height: var(--heading-3-line-height);
    color: var(--text-dark);
    margin-bottom: 8px;
}

.feature-desc {
    font-size: 14px;
    line-height: 21px;
    color: var(--text-gray);
}

.features-image {
    flex: 1;
}

.signature-screen-image {
    width: 100%;
    height: auto;
}

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

.tech-card {
    background: var(--white);
    border: 0.667px solid var(--border-gray);
    border-radius: var(--border-radius-card);
    padding: 24px;
}

.tech-icon {
    width: 32px;
    height: 32px;
    margin-bottom: 12px;
}

.tech-card-title {
    font-size: 18px;
    font-weight: 700;
    line-height: 28px;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.tech-card-text {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

/* Technology Section */
.technology-section {
    padding: 80px 56px;
}

.technology-container {
    display: flex;
    gap: 48px;
    align-items: center;
}

.tech-image {
    flex: 1;
}

.audit-cert-image {
    width: 100%;
    height: auto;
}

.tech-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.tech-title {
    font-size: var(--heading-2-size);
    font-weight: var(--heading-2-weight);
    line-height: var(--heading-2-line-height);
    color: var(--text-dark);
}

.tech-description {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.tech-text {
    font-size: var(--paragraph-size);
    line-height: 24px;
    color: var(--text-gray);
}

.tech-standards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.standard-badge {
    background: rgba(239, 246, 255, 0.5);
    border: 0.667px solid var(--border-gray);
    border-radius: 10px;
    padding: 16.667px;
}

.standard-title {
    font-size: 24px;
    font-weight: 700;
    line-height: 32px;
    color: var(--primary-blue);
    margin-bottom: 4px;
}

.standard-subtitle {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

/* Free Features Section */
.free-features-section {
    padding: 64px 152px;
    background: rgba(239, 246, 255, 0.2);
}

.free-features-card {
    background: var(--white);
    border: 0.667px solid var(--border-gray);
    border-radius: var(--border-radius-card);
    padding: 32.667px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 36px 48px;
}

.free-feature {
    display: flex;
    gap: 12px;
    align-items: flex-start;
}

.icon-check-purple {
    flex-shrink: 0;
}

.free-feature-text {
    flex: 1;
}

.free-feature-title {
    font-size: 16px;
    font-weight: 700;
    line-height: 24px;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.free-feature-desc {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

/* CTA Section */
.cta-section {
    padding: 64px 216px;
}

.cta-container {
    text-align: center;
}

.cta-title {
    font-size: var(--heading-2-size);
    font-weight: var(--heading-2-weight);
    line-height: var(--heading-2-line-height);
    color: var(--text-dark);
    margin-bottom: 32px;
}

.cta-subtitle {
    font-size: 20px;
    line-height: 28px;
    color: var(--text-gray);
    margin-bottom: 32px;
}

/* Footer */
.intro-footer {
    background: var(--white);
    border-top: 0.667px solid var(--border-gray);
    padding: 48.667px 24px 0;
}

.footer-container {
    display: flex;
    flex-direction: column;
    gap: 48px;
}

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

.footer-logo {
    height: 32px;
    width: auto;
    margin-bottom: 16px;
}

.footer-tagline {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

.footer-heading {
    font-size: 16px;
    font-weight: 700;
    line-height: 24px;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.footer-links a {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
    text-decoration: none;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: var(--primary-blue);
}

.footer-contact {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-contact-item {
    display: flex;
    align-items: flex-start;
    gap: 8px;
}

.footer-contact-item span {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

.footer-contact-text {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.footer-contact-text div {
    font-size: 14px;
    line-height: 20px;
    color: var(--text-gray);
}

.footer-bottom {
    border-top: 0.667px solid var(--border-gray);
    padding: 32px 0;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.footer-legal {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    font-size: 14px;
    line-height: 20px;
}

.footer-legal a {
    color: var(--text-gray);
    text-decoration: none;
    transition: color 0.2s;
    cursor: pointer;
}

.footer-legal a:hover {
    color: var(--primary-blue);
}

.footer-legal span {
    color: var(--border-gray);
}

.footer-info {
    display: flex;
    flex-direction: column;
    gap: 8px;
    text-align: center;
}

.footer-company-name {
    font-size: 14px;
    line-height: 20px;
    font-weight: 700;
    color: var(--text-dark);
    margin: 0;
}

.footer-company-info,
.footer-company-address,
.footer-company-detail {
    font-size: 12px;
    line-height: 18px;
    color: var(--text-gray);
    margin: 0;
}

.footer-copyright {
    font-size: 12px;
    line-height: 18px;
    color: var(--text-gray);
    text-align: center;
    border-top: 0.667px solid var(--border-gray);
    padding-top: 24px;
}

/* ========== 5. Tablet Styles (768px - 1023px) ========== */
@media (min-width: 768px) and (max-width: 1023px) {
    .container {
        max-width: 720px;
    }

    .intro-header {
        padding: 0 24px;
    }

    .hero-section {
        padding: 80px 0;
    }

    .hero-container {
        gap: 48px;
    }

    .hero-title {
        font-size: 36px;
        line-height: 48px;
    }

    .promo-section {
        padding: 64px 0;
    }

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

    .features-content {
        flex-direction: column-reverse;
        gap: 32px;
    }

    .tech-cards {
        grid-template-columns: repeat(2, 1fr);
    }

    .technology-container {
        flex-direction: column;
    }

    .tech-standards {
        grid-template-columns: repeat(2, 1fr);
    }

    .free-features-section {
        padding: 64px 48px;
    }

    .cta-section {
        padding: 64px 96px;
    }

    .footer-columns {
        grid-template-columns: repeat(2, 1fr);
        gap: 48px 32px;
    }
}

/* ========== 6. Mobile Styles (Max 767px) ========== */
@media (max-width: 767px) {
    .container {
        padding: 0 16px;
    }

    /* Header */
    .intro-header {
        padding: 0 16px;
        height: 56px;
    }

    .header-container {
        height: 56px;
    }

    .logo {
        height: 24px;
    }

    .header-nav {
        gap: 8px;
    }

    .btn-login,
    .btn-logout,
    .btn-start,
    .btn-dashboard {
        padding: 0 12px;
        height: 28px;
        line-height: 28px;
        font-size: 12px;
    }

    /* Hero Section */
    .hero-section {
        min-height: auto;
        padding: 40px 0;
    }

    .hero-container {
        flex-direction: column;
        gap: 32px;
    }

    .hero-title {
        font-size: 36px;
        line-height: 46px;
    }

    .hero-subtitle {
        font-size: 14px;
        line-height: 22px;
    }

    .btn-hero {
        margin: 0 auto;
        width: 100%;
        display: flex;
        justify-content: center;
        align-items: center;
    }

    /* Promo Section */
    .promo-section {
        min-height: auto;
        padding: 48px 0;
    }

    .promo-title {
        font-size: 32px;
        line-height: 40px;
    }

    .promo-subtitle {
        font-size: 16px;
        line-height: 24px;
    }

    .promo-cards {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .promo-features {
        flex-direction: column;
        align-items: center;
        gap: 12px;
    }

    /* Why Section */
    .why-section {
        padding: 48px 0;
    }

    .section-title {
        font-size: 24px;
        line-height: 32px;
        margin-bottom: 32px;
    }

    .why-cards {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    /* Features Section */
    .features-section {
        padding: 48px 0;
    }

    .features-content {
        flex-direction: column-reverse;
        gap: 32px;
        margin-bottom: 32px;
    }

    .features-list {
        padding-top: 0;
    }

    .tech-cards {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    /* Technology Section */
    .technology-section {
        padding: 48px 16px;
    }

    .technology-container {
        flex-direction: column;
        gap: 32px;
    }

    .tech-title {
        font-size: 24px;
        line-height: 32px;
    }

    .tech-standards {
        grid-template-columns: 1fr;
    }

    /* Free Features Section */
    .free-features-section {
        padding: 48px 16px;
    }

    .free-features-card {
        grid-template-columns: 1fr;
        gap: 24px;
        padding: 24px;
    }

    /* CTA Section */
    .cta-section {
        padding: 48px 16px;
    }

    .cta-title {
        font-size: 24px;
        line-height: 32px;
    }

    .cta-subtitle {
        font-size: 16px;
        line-height: 24px;
    }

    /* Footer */
    .intro-footer {
        padding: 32px 16px 0;
    }

    .footer-columns {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .footer-legal {
        flex-wrap: wrap;
        gap: 8px;
    }

    .footer-info {
        text-align: left;
    }
}

/* ========== 약관 모달 ========== */
#coverBG {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 9998;
}

.pop-layer {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    border-radius: 16px;
    padding: 40px;
    max-width: 800px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    z-index: 9999;
    display: none;
}

.pop-layer.show {
    display: block;
}

/* 약관 모달 내부 스타일 */
.pop-layer .pop-container {
    width: 100%;
    padding: 20px 0 20px 25px;
    box-sizing: border-box;
}

.pop-layer .xBtn {
    display: block;
    position: absolute;
    top: 10px;
    right: 10px;
    cursor: pointer;
}

.pop-layer .xBtn img {
    width: 20px;
}

.pop-layer .pop-conts .title {
    text-align: center;
    margin: 20px 0;
}

.pop-layer .pop-conts .title span {
    display: inline-block;
    font-size: 24px;
    font-weight: bold;
    color: #333;
    text-align: center;
    padding-bottom: 5px;
    border-bottom: 2px solid #333;
}

.pop-layer .pop-conts .subTitle {
    font-size: 16px;
    font-weight: bold;
    color: #333;
    margin-top: 30px;
    margin-bottom: 10px;
    line-height: 1.4;
}

.pop-layer .pop-conts .textBox {
    width: 100%;
    max-height: 558px;
    overflow-y: auto;
}

.pop-layer .pop-conts .text01 {
    font-size: 14px;
    color: #333;
    line-height: 1.6;
}

.pop-layer .pop-conts .text02 {
    font-size: 14px;
    color: #333;
    line-height: 1.6;
}

.pop-layer .pop-conts .text02 div {
    line-height: 1.6;
}

.pop-layer .pop-conts .text02 table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.pop-layer .pop-conts .text02 table th {
    font-size: 14px;
    font-weight: bold;
    color: #333;
    border: 1px dotted #ddd;
    background-color: #f4f4f4;
    text-align: center;
    padding: 10px 5px;
}

.pop-layer .pop-conts .text02 table td {
    font-size: 14px;
    color: #333;
    border: 1px dotted #ddd;
    text-align: center;
    padding: 10px 5px;
}

/* 모바일 모달 스타일 */
@media (max-width: 767px) {
    .pop-layer {
        padding: 24px;
        width: 95%;
        max-height: 90vh;
    }

    .pop-layer .pop-container {
        padding: 20px 10px;
    }

    .pop-layer .pop-conts .title span {
        font-size: 20px;
    }

    .pop-layer .pop-conts .subTitle {
        font-size: 14px;
    }

    .pop-layer .pop-conts .text01,
    .pop-layer .pop-conts .text02 {
        font-size: 12px;
    }

    .pop-layer .pop-conts .text02 table th,
    .pop-layer .pop-conts .text02 table td {
        font-size: 12px;
    }

    .pop-layer .pop-conts .textBox {
        max-height: calc(100vh - 125px);
    }
}

/* ========== 7. Additional Utilities ========== */
/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Image loading optimization */
picture {
    display: block;
    width: 100%;
}

picture img {
    display: block;
    width: 100%;
    height: auto;
}

/* Focus styles for accessibility */
a:focus,
button:focus {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
}

/* Hover states */
.btn-login:hover,
.btn-logout:hover {
    background: #f9fafb;
    border-color: var(--primary-blue);
}