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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ffffff;
}

.container {
    width: 100%;
    max-width: 600px;
    padding: 40px 20px;
    text-align: center;
}

header h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    font-size: 1.1rem;
    color: #a0a0a0;
    margin-bottom: 50px;
}

.url-form {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
}

#urlInput {
    flex: 1;
    padding: 16px 20px;
    font-size: 1rem;
    border: 2px solid #333;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.05);
    color: #ffffff;
    outline: none;
    transition: border-color 0.3s, box-shadow 0.3s;
}

#urlInput:focus {
    border-color: #00d4ff;
    box-shadow: 0 0 20px rgba(0, 212, 255, 0.2);
}

#urlInput::placeholder {
    color: #666;
}

#shortenBtn {
    padding: 16px 32px;
    font-size: 1rem;
    font-weight: 600;
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    border: none;
    border-radius: 12px;
    color: #ffffff;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

#shortenBtn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(0, 212, 255, 0.3);
}

#shortenBtn:active {
    transform: translateY(0);
}

.result {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 30px;
    margin-bottom: 20px;
}

.result p {
    color: #a0a0a0;
    margin-bottom: 15px;
}

.short-url-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 15px;
}

#shortUrl {
    font-size: 1.4rem;
    font-weight: 600;
    color: #00d4ff;
    text-decoration: none;
    word-break: break-all;
}

#shortUrl:hover {
    text-decoration: underline;
}

#copyBtn {
    padding: 10px 20px;
    font-size: 0.9rem;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    color: #ffffff;
    cursor: pointer;
    transition: background 0.2s;
}

#copyBtn:hover {
    background: rgba(255, 255, 255, 0.2);
}

.expiry-note {
    font-size: 0.85rem;
    color: #666 !important;
    margin-bottom: 0 !important;
}

.error {
    background: rgba(255, 71, 87, 0.1);
    border: 1px solid rgba(255, 71, 87, 0.3);
    border-radius: 12px;
    padding: 15px 20px;
    color: #ff4757;
}

.hidden {
    display: none;
}

footer {
    margin-top: 50px;
    color: #555;
    font-size: 0.9rem;
}

@media (max-width: 500px) {
    .url-form {
        flex-direction: column;
    }
    
    #shortenBtn {
        width: 100%;
    }
    
    header h1 {
        font-size: 2.5rem;
    }
    
    .short-url-container {
        flex-direction: column;
        gap: 10px;
    }
}