/* Reset & Base */
:root {
    --primary-color: #2563eb;
    /* Vivid Blue */
    --primary-dark: #1e40af;
    --text-main: #111827;
    /* Almost Black */
    --text-sub: #4b5563;
    /* Gray */
    --bg-color: #f3f4f6;
    /* Light Gray Blue */
    --white: #ffffff;
    --shadow-soft: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-card: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

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

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, "Helvetica Neue", "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

/* Layout Utilities */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background-color: var(--white);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 20px;
}

.logo-bold {
    font-weight: 800;
    color: #0f172a;
    letter-spacing: -0.02em;
}

.divider {
    color: #cbd5e1;
    font-weight: 300;
    font-size: 18px;
}

.logo-text {
    font-weight: 600;
    color: #334155;
    font-size: 18px;
    letter-spacing: -0.01em;
}

.kakao-header-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    background-color: #FEE500;
    color: #191919;
    padding: 10px 24px;
    border-radius: 9999px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.2s ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.kakao-header-btn:hover {
    background-color: #fadd00;
    transform: translateY(-1px);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

/* Main Content */
main {
    padding: 80px 0;
    min-height: calc(100vh - 160px);
    display: flex;
    align-items: center;
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    width: 100%;
}

/* Left Column: Intro */
.intro-section {
    padding-right: 0;
}

.badge {
    display: inline-flex;
    align-items: center;
    background-color: #eff6ff;
    color: var(--primary-color);
    font-size: 13px;
    font-weight: 700;
    padding: 8px 16px;
    border-radius: 9999px;
    margin-bottom: 24px;
    letter-spacing: 0.02em;
    text-transform: uppercase;
}

.main-title {
    font-size: 56px;
    line-height: 1.15;
    color: #0f172a;
    margin-bottom: 24px;
    font-weight: 800;
    letter-spacing: -0.03em;
    word-break: keep-all;
}

.brand-name {
    color: #0f172a;
}

.title-highlight {
    color: var(--primary-color);
}

.description {
    font-size: 18px;
    color: #475569;
    margin-bottom: 48px;
    line-height: 1.7;
    font-weight: 400;
    letter-spacing: -0.01em;
    word-break: keep-all;
}

/* Action Buttons */
.action-area {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 48px;
    max-width: 360px;
}

.download-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    background-color: #0f172a;
    color: var(--white);
    padding: 20px;
    border-radius: 16px;
    font-size: 18px;
    font-weight: 700;
    transition: all 0.2s ease;
    box-shadow: 0 10px 15px -3px rgba(15, 23, 42, 0.2);
    letter-spacing: -0.01em;
}

.download-btn:hover {
    background-color: #1e293b;
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(15, 23, 42, 0.2);
}

.copy-link-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    color: #64748b;
    font-size: 15px;
    font-weight: 500;
    padding: 8px;
    transition: color 0.2s;
}

.copy-link-btn:hover {
    color: var(--primary-color);
}

/* Security Note */
.security-note {
    background-color: rgba(255, 255, 255, 0.6);
    padding: 20px 24px;
    border-radius: 12px;
    font-size: 14px;
    color: #475569;
    line-height: 1.6;
    border: 1px solid rgba(226, 232, 240, 0.8);
    backdrop-filter: blur(4px);
}

.security-note strong {
    color: #0f172a;
    font-weight: 700;
}

.guide-link {
    display: inline-block;
    color: var(--primary-color);
    font-weight: 600;
    cursor: pointer;
    margin-top: 4px;
    margin-bottom: 12px;
    text-decoration: underline;
    text-underline-offset: 4px;
}

.guide-link:hover {
    color: var(--primary-dark);
}

.sub-note {
    font-size: 13px;
    color: #94a3b8;
    margin-top: 8px;
    border-top: 1px solid #e2e8f0;
    padding-top: 8px;
}

/* Right Column: Guide Card */
.guide-section {
    display: flex;
    justify-content: flex-end;
}

.guide-card {
    background-color: var(--white);
    padding: 56px;
    border-radius: 40px;
    box-shadow: var(--shadow-card);
    width: 100%;
    max-width: 480px;
    position: relative;
    overflow: hidden;
}

.guide-card::before {
    content: '';
    position: absolute;
    top: -50px;
    right: -50px;
    width: 150px;
    height: 150px;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.05) 0%, rgba(255, 255, 255, 0) 70%);
    border-radius: 50%;
    z-index: 0;
}

.card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 40px;
    position: relative;
    z-index: 1;
}

.card-header i {
    color: var(--primary-color);
    font-size: 24px;
}

.card-header h2 {
    font-size: 22px;
    font-weight: 700;
    color: #0f172a;
    letter-spacing: -0.02em;
}

.step-list {
    display: flex;
    flex-direction: column;
    gap: 32px;
    position: relative;
    z-index: 1;
}

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

.step-number {
    flex-shrink: 0;
    width: 36px;
    height: 36px;
    background-color: #f1f5f9;
    color: #475569;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 16px;
    margin-top: 2px;
}

.step-content h3 {
    font-size: 17px;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 6px;
    letter-spacing: -0.01em;
}

.step-content p {
    font-size: 15px;
    color: #64748b;
    line-height: 1.5;
    letter-spacing: -0.01em;
    word-break: keep-all;
}

.highlight-text {
    color: var(--primary-color);
    font-weight: 700;
}

/* Footer */
footer {
    text-align: center;
    padding: 40px 0;
    color: #94a3b8;
    font-size: 13px;
    border-top: 1px solid #e2e8f0;
    background-color: #f8fafc;
}

.footer-logo {
    font-weight: 700;
    color: #cbd5e1;
    margin-bottom: 8px;
    font-size: 16px;
    letter-spacing: -0.01em;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .main-title {
        font-size: 42px;
    }

    .content-wrapper {
        gap: 40px;
    }
}

@media (max-width: 768px) {
    main {
        padding: 40px 0;
    }

    .content-wrapper {
        grid-template-columns: 1fr;
        gap: 60px;
    }

    .intro-section {
        text-align: center;
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .main-title {
        font-size: 36px;
    }

    .description {
        font-size: 16px;
    }

    .guide-section {
        justify-content: center;
    }

    .guide-card {
        padding: 32px;
        border-radius: 32px;
    }

    .header-inner {
        padding: 0 10px;
    }
}