:root {
    --primary-color: #3b82f6;
    --primary-dark: #2563eb;
    --primary-light: #60a5fa;
    --secondary-color: #10b981;
    --bg-color: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --text-color: #ffffff;
    --text-light: #a8a8a8;
    --text-secondary: #666666;
    --card-bg: #161616;
    --border-color: #2a2a2a;
    --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.6);
    --gradient-primary: linear-gradient(135deg, #3b82f6 0%, #60a5fa 100%);
    --gradient-secondary: linear-gradient(135deg, #10b981 0%, #34d399 100%);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    transition: opacity 0.5s ease;
}

.loading-content {
    text-align: center;
}

.loading-icon {
    position: relative;
    width: 100px;
    height: 100px;
    margin: 0 auto;
}

.loading-icon div {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    border: 10px solid transparent;
    border-top-color: var(--primary-color);
    animation: spin 1.5s linear infinite;
}

.loading-icon div:nth-child(2) {
    border-top-color: var(--secondary-color);
    animation: spin 2s linear infinite;
}

.loader-wave {
    display: flex;
    justify-content: center;
    margin-top: 20px;
}

.loader-wave span {
    display: inline-block;
    width: 10px;
    height: 10px;
    margin: 0 5px;
    border-radius: 50%;
    background-color: var(--primary-color);
    animation: wave 1.5s infinite ease-in-out;
}

.loader-wave span:nth-child(2) { animation-delay: 0.2s; }
.loader-wave span:nth-child(3) { animation-delay: 0.4s; background-color: var(--secondary-color); }
.loader-wave span:nth-child(4) { animation-delay: 0.6s; }
.loader-wave span:nth-child(5) { animation-delay: 0.8s; }

@keyframes wave {
    0%, 40%, 100% { transform: translateY(0); }
    20% { transform: translateY(-15px); }
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.header {
    background: rgba(22, 22, 22, 0.95);
    border-bottom: 1px solid var(--border-color);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.header h1 {
    font-size: 28px;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.header p {
    font-size: 14px;
    margin-top: 6px;
    color: var(--text-light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 24px 80px;
}

.shorten-section {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 40px;
    border-radius: 24px;
    box-shadow: var(--shadow-md);
    margin-bottom: 40px;
}

.input-container {
    max-width: 800px;
    margin: 0 auto;
}

.input-group {
    margin-bottom: 16px;
}

.url-input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

#long-url {
    width: 100%;
    padding: 18px 20px;
    border: 2px solid var(--border-color);
    border-radius: 16px;
    font-size: 15px;
    outline: none;
    transition: all 0.3s;
    background: var(--bg-secondary);
    color: var(--text-color);
    font-weight: 500;
}

#long-url:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.1);
}

.shorten-btn {
    width: 100%;
    padding: 18px 36px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 16px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    box-shadow: 0 4px 20px rgba(59, 130, 246, 0.3);
}

.shorten-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(59, 130, 246, 0.4);
}

.loader {
    display: none;
    text-align: center;
    padding: 60px 20px;
}

.loader.active { display: block; }

.loader-spinner {
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    width: 60px;
    height: 60px;
    animation: spin 1s linear infinite;
    margin: 0 auto 24px;
}

.error-message {
    background: var(--card-bg);
    border: 2px solid rgba(239, 68, 68, 0.3);
    border-radius: 20px;
    padding: 40px 30px;
    text-align: center;
    margin: 40px 0;
    display: none;
}

.error-message.active { display: block; }

.error-message i {
    font-size: 48px;
    color: #ef4444;
    margin-bottom: 16px;
}

.error-message h3 {
    color: #ef4444;
    font-size: 24px;
    margin-bottom: 8px;
}

.result-container {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    margin-bottom: 40px;
}

.result-header {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, transparent 100%);
    padding: 32px;
    border-bottom: 1px solid var(--border-color);
}

.result-header h2 {
    font-size: 24px;
    text-align: center;
}

.result-content {
    padding: 32px;
}

.short-url-display {
    display: flex;
    gap: 12px;
    margin-bottom: 24px;
}

#short-url-text {
    flex: 1;
    padding: 16px 20px;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--primary-color);
    font-size: 16px;
    font-weight: 600;
}

.copy-btn {
    padding: 16px 24px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    gap: 8px;
}

.copy-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.url-info {
    margin-bottom: 24px;
}

.info-item {
    background: var(--bg-secondary);
    padding: 20px;
    border-radius: 12px;
    display: flex;
    gap: 16px;
    align-items: center;
}

.info-item i {
    font-size: 32px;
    color: var(--primary-color);
}

.info-label {
    display: block;
    font-size: 12px;
    color: var(--text-light);
    margin-bottom: 4px;
}

.info-value {
    display: block;
    font-size: 16px;
    font-weight: 600;
    word-break: break-all;
}

.action-buttons {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

.new-link-btn {
    padding: 14px 28px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.new-link-btn:hover {
    transform: translateY(-2px);
}

.features-section {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 60px 40px;
    border-radius: 24px;
    box-shadow: var(--shadow-md);
}

.features-section h2 {
    text-align: center;
    font-size: 32px;
    margin-bottom: 48px;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.feature-card {
    text-align: center;
    padding: 32px 24px;
    border-radius: 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.feature-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(59, 130, 246, 0.15);
}

.feature-card i {
    font-size: 48px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 16px;
}

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

.feature-card p {
    color: var(--text-light);
    font-size: 14px;
}

footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    color: var(--text-light);
    padding: 32px 0;
    text-align: center;
}

@media (max-width: 768px) {
    .shorten-section {
        padding: 32px 24px;
    }
    
    .short-url-display {
        flex-direction: column;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
}