/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
 
:root {
    --primary-color: #1e88e5;
    --secondary-color: #00d9ff;
    --success-color: #26a69a;
    --warning-color: #ffa726;
    --danger-color: #ef5350;
    --dark-bg: #0f1419;
    --card-bg: #1a1f29;
    --text-primary: #ffffff; 
    --text-secondary: #8899a6;
    --border-color: #2f3641;
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #1e88e5 0%, #00d9ff 100%);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Navigation */
.header {
    background: rgba(26, 31, 41, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--text-primary);
}

.logo i {
    color: var(--secondary-color);
    font-size: 1.8rem;
}

.nav-menu {
    display: flex;
    gap: 3rem;
    list-style: none;
    margin-left: auto;
    margin-right: 2rem;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: var(--text-primary);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 3px;
    transition: all 0.3s;
}

/* Hero Section */
.hero {
    padding: 150px 0 100px;
    background: linear-gradient(135deg, #0f1419 0%, #1a1f29 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(30, 136, 229, 0.1) 0%, transparent 70%);
    top: -250px;
    right: -250px;
    border-radius: 50%;
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.highlight {
    background: var(--gradient-2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.3rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    margin-bottom: 4rem;
}

.btn-primary {
    background: var(--gradient-2);
    color: white;
    border: none;
    padding: 1rem 2.5rem;
    border-radius: 12px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(30, 136, 229, 0.4);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    padding: 1rem 2.5rem;
    border-radius: 12px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-secondary:hover {
    border-color: var(--primary-color);
    background: rgba(30, 136, 229, 0.1);
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: 3rem;
    padding-top: 3rem;
    border-top: 1px solid var(--border-color);
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.feature-item i {
    font-size: 2.5rem;
    color: var(--secondary-color);
}

.feature-item h4 {
    font-size: 1.1rem;
    margin-bottom: 0.3rem;
    color: var(--text-primary);
}

.feature-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Exchange Section */
.exchange-section {
    padding: 100px 0;
    background: var(--dark-bg);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 3rem;
}

.exchange-container {
    display: flex;
    justify-content: center;
    max-width: 1000px;
    margin: 0 auto;
}

.exchange-card-full {
    width: 100%;
    max-width: 600px;
}

.exchange-card {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.exchange-tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.tab-btn {
    flex: 1;
    padding: 1rem;
    background: transparent;
    color: var(--text-secondary);
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    transition: all 0.3s;
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.input-wrapper {
    display: flex;
    align-items: center;
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 0.5rem 1rem;
    transition: border-color 0.3s;
    min-height: 60px;
}

.input-wrapper:focus-within {
    border-color: var(--primary-color);
}

.input-wrapper input {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1.3rem;
    font-weight: 600;
    outline: none;
    min-width: 0;
}

.input-wrapper select {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    outline: none;
    min-width: 80px;
}

.currency-label {
    color: var(--text-secondary);
    font-weight: 600;
    padding: 0.5rem;
    min-width: 60px;
    text-align: right;
}

.exchange-icon {
    text-align: center;
    margin: 1rem 0;
}

.exchange-icon i {
    color: var(--secondary-color);
    font-size: 1.5rem;
}

.exchange-rate {
    background: var(--dark-bg);
    border-radius: 12px;
    padding: 1rem;
    margin-bottom: 1.5rem;
}

.rate-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
}

.rate-info:last-child {
    margin-bottom: 0;
}

.rate-info span:first-child {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.rate-value {
    color: var(--text-primary);
    font-weight: 600;
}

.fee-value {
    color: var(--success-color);
    font-weight: 600;
}

.btn-exchange {
    width: 100%;
    padding: 1.2rem;
    background: var(--gradient-2);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-exchange:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(30, 136, 229, 0.4);
}

/* Market Info Card */
.market-info-card {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.market-info-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.market-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.market-item:last-child {
    border-bottom: none;
}

.market-label {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    color: var(--text-secondary);
}

.market-label i {
    color: var(--secondary-color);
    font-size: 1.2rem;
}

.market-value {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.market-value.positive {
    color: var(--success-color);
}

.market-value.negative {
    color: var(--danger-color);
}

/* How It Works Section */
.how-it-works {
    padding: 100px 0;
    background: linear-gradient(135deg, #1a1f29 0%, #0f1419 100%);
}

.steps-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.step-card {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 2.5rem 2rem;
    text-align: center;
    border: 1px solid var(--border-color);
    position: relative;
    transition: transform 0.3s, box-shadow 0.3s;
}

.step-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.step-number {
    position: absolute;
    top: -20px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 40px;
    background: var(--gradient-2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
    color: white;
}

.step-icon {
    margin: 2rem 0 1.5rem;
}

.step-icon i {
    font-size: 3rem;
    color: var(--secondary-color);
}

.step-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.step-card p {
    color: var(--text-secondary);
    line-height: 1.8;
}

/* Features Section */
.features {
    padding: 100px 0;
    background: var(--dark-bg);
}

.features .section-title {
    margin-bottom: 4rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.feature-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 70px;
    height: 70px;
    background: var(--gradient-2);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.feature-icon i {
    font-size: 2rem;
    color: white;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 0.95rem;
}

/* Contact Section */
.contact {
    padding: 100px 0;
    background: linear-gradient(135deg, #1a1f29 0%, #0f1419 100%);
}

.contact-kakao {
    max-width: 600px;
    margin: 0 auto;
}

.kakao-content {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 4rem 3rem;
    text-align: center;
    border: 1px solid var(--border-color);
}

.kakao-icon {
    width: 100px;
    height: 100px;
    background: linear-gradient(135deg, #FEE500 0%, #FFD700 100%);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 2rem;
}

.kakao-icon i {
    font-size: 3.5rem;
    color: #3c1e1e;
}

.kakao-content h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.kakao-content p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
}

.btn-kakao {
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    background: #FEE500;
    color: #3c1e1e;
    padding: 1.2rem 3rem;
    border-radius: 12px;
    font-size: 1.2rem;
    font-weight: 700;
    text-decoration: none;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-kakao:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(254, 229, 0, 0.4);
}

.btn-kakao i {
    font-size: 1.5rem;
}

/* Footer */
.footer {
    background: var(--card-bg);
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    text-align: center;
    padding: 1rem 0;
}

.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 0.8rem;
}

.footer-logo i {
    color: var(--secondary-color);
    font-size: 1.8rem;
}

.footer-text {
    color: var(--text-secondary);
    margin-bottom: 0;
}

.footer-bottom {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 992px) {
    .nav-menu {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-features {
        gap: 2rem;
    }

    .exchange-card-full {
        max-width: 100%;
    }

    .steps-container {
        grid-template-columns: 1fr;
    }

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

    .kakao-content {
        padding: 3rem 2rem;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

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

    .btn-primary,
    .btn-secondary {
        width: 100%;
        max-width: 300px;
    }

    .hero-features {
        flex-direction: column;
        gap: 1.5rem;
        align-items: center;
    }

    .section-title {
        font-size: 2rem;
    }

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

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.6rem;
    }

    .input-wrapper input {
        font-size: 1.1rem;
    }

    .exchange-card,
    .kakao-content {
        padding: 2rem 1.5rem;
    }

    .btn-kakao {
        padding: 1rem 2rem;
        font-size: 1rem;
    }
}