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

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --text: #1a1a1a;
    --text-secondary: #666;
    --border: #e0e0e0;
    --bg: #ffffff;
    --bg-secondary: #f8f9fa;
    --radius: 12px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.wrapper {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 32px 0;
    border-bottom: 1px solid var(--border);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    font-size: 18px;
    color: var(--text);
}

.logo svg {
    color: var(--primary);
}

nav {
    display: flex;
    gap: 32px;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 15px;
    transition: color 0.2s;
}

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

/* Hero */
.hero {
    text-align: center;
    padding: 80px 0;
}

h1 {
    font-size: 56px;
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.1;
    margin-bottom: 20px;
}

.hero > p {
    font-size: 20px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 48px;
}

/* Demo */
.demo {
    max-width: 600px;
    margin: 0 auto;
}

.input-group {
    display: flex;
    gap: 8px;
}

input[type="url"] {
    flex: 1;
    padding: 16px 20px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 15px;
    font-family: inherit;
    transition: border-color 0.2s;
}

input[type="url"]:focus {
    outline: none;
    border-color: var(--primary);
}

button {
    padding: 16px 32px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s;
    font-family: inherit;
}

button:hover {
    background: var(--primary-dark);
}

button:active {
    transform: translateY(1px);
}

.result {
    margin-top: 24px;
    padding: 20px;
    background: var(--bg-secondary);
    border-radius: var(--radius);
}

.result.hidden {
    display: none;
}

.result-url {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 12px 16px;
    background: white;
    border: 1px solid var(--border);
    border-radius: 8px;
    margin-bottom: 12px;
}

#short-url {
    font-family: 'SF Mono', 'Monaco', 'Courier New', monospace;
    font-size: 16px;
    color: var(--primary);
}

.copy-btn {
    padding: 8px 16px;
    font-size: 14px;
}

.result-hint {
    font-size: 14px;
    color: var(--text-secondary);
    text-align: center;
}

.result-qr {
    text-align: center;
    margin: 20px 0;
}

#qr-code {
    width: 200px;
    height: 200px;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px;
    background: white;
}

.qr-hint {
    font-size: 13px;
    color: var(--text-secondary);
    margin-top: 8px;
}

/* Deep Linking Section */
.deep-linking {
    padding: 80px 0;
    background: var(--bg-secondary);
    margin: 0 -24px;
    padding-left: 24px;
    padding-right: 24px;
}

.deep-linking h2 {
    font-size: 40px;
    font-weight: 600;
    margin-bottom: 16px;
    text-align: center;
}

.section-intro {
    text-align: center;
    color: var(--text-secondary);
    font-size: 18px;
    max-width: 700px;
    margin: 0 auto 48px;
    line-height: 1.6;
}

.dl-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 32px;
    margin-bottom: 64px;
}

.dl-feature {
    text-align: center;
    padding: 24px;
}

.dl-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.dl-feature h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 12px;
}

.dl-feature p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

.flow-diagram {
    max-width: 900px;
    margin: 0 auto;
    padding: 32px;
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.flow-diagram h3 {
    text-align: center;
    font-size: 20px;
    margin-bottom: 32px;
}

.flow-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.flow-step {
    flex: 1;
    min-width: 180px;
    text-align: center;
    padding: 24px;
    background: var(--bg-secondary);
    border-radius: 8px;
}

.step-number {
    display: inline-block;
    width: 32px;
    height: 32px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    line-height: 32px;
    font-weight: 600;
    margin-bottom: 12px;
}

.flow-arrow {
    font-size: 24px;
    color: var(--text-secondary);
    font-weight: 600;
}

/* Features */
.features {
    padding: 80px 0;
}

.features h2 {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 48px;
    text-align: center;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 32px;
}

.feature {
    text-align: center;
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.feature h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

.feature p {
    color: var(--text-secondary);
    font-size: 15px;
}

/* API */
.api {
    padding: 80px 0;
}

.api h2 {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 24px;
    text-align: center;
}

.code-block {
    background: #1a1a1a;
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 24px;
}

.code-block pre {
    overflow-x: auto;
}

.code-block code {
    font-family: 'SF Mono', 'Monaco', 'Courier New', monospace;
    font-size: 14px;
    line-height: 1.6;
    color: #e0e0e0;
}

.code-method {
    color: #10b981;
    font-weight: 600;
}

.api-intro {
    text-align: center;
    color: var(--text-secondary);
    font-size: 18px;
    margin: 0 0 32px;
}

.api-details {
    max-width: 700px;
    margin: 32px auto 0;
    padding: 24px;
    background: var(--bg-secondary);
    border-radius: var(--radius);
}

.api-details h3 {
    font-size: 18px;
    margin-bottom: 12px;
}

.api-details ul {
    list-style: none;
    padding: 0;
    margin: 0 0 24px;
}

.api-details li {
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
}

.api-details li:last-child {
    border-bottom: none;
}

.api-details p {
    color: var(--text-secondary);
    margin: 0;
}

/* Footer */
footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px 0;
    border-top: 1px solid var(--border);
    font-size: 14px;
    color: var(--text-secondary);
}

footer div {
    display: flex;
    gap: 12px;
    align-items: center;
}

footer a {
    color: var(--text-secondary);
    text-decoration: none;
}

footer a:hover {
    color: var(--text);
}

/* Responsive */
@media (max-width: 768px) {
    h1 {
        font-size: 40px;
    }

    .hero > p {
        font-size: 18px;
    }

    .input-group {
        flex-direction: column;
    }

    nav {
        gap: 20px;
    }

    .deep-linking h2 {
        font-size: 32px;
    }

    .flow-steps {
        flex-direction: column;
    }

    .flow-arrow {
        transform: rotate(90deg);
    }

    footer {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}