/* Reset và Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

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

/* Header */
.header {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
}

.logo-img {
    width: 50px;
    height: 50px;
    object-fit: contain;
    border-radius: 8px;
}

.logo i {
    color: #4ade80;
    font-size: 2rem;
}

.nav-buttons {
    display: flex;
    gap: 10px;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
}

.btn-primary {
    background: #4ade80;
    color: white;
}

.btn-primary:hover {
    background: #22c55e;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.6);
}

/* Main Content */
.main {
    padding: 2rem 0;
    flex: 1;
}

/* Hero Section */
.hero {
    text-align: center;
    margin-bottom: 3rem;
    color: white;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(45deg, #4ade80, #22d3ee);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Login Required */
.login-required {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
}

.login-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 3rem;
    text-align: center;
    color: white;
    max-width: 400px;
}

.login-card i {
    font-size: 4rem;
    color: #4ade80;
    margin-bottom: 1rem;
}

.login-card h2 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.login-card p {
    margin-bottom: 2rem;
    opacity: 0.8;
}

/* Shortener Section */
.shortener-section {
    max-width: 800px;
    margin: 0 auto;
}

.shortener-card, .result-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 2rem;
    margin-bottom: 2rem;
    color: white;
}

.shortener-card h2 {
    margin-bottom: 1.5rem;
    text-align: center;
    color: #4ade80;
}

.input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 1rem;
}

.input-group input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 16px;
}

.input-group input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.input-group input:focus {
    outline: none;
    border-color: #4ade80;
}

.form-options {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.form-options label {
    flex: 1;
    min-width: 200px;
}

.form-options input {
    width: 100%;
    padding: 10px 12px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

.form-options input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

/* URL Result */
.url-result {
    animation: slideIn 0.5s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-url {
    display: flex;
    gap: 10px;
    margin-bottom: 1rem;
}

.result-url input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-weight: 500;
}

.qr-code {
    text-align: center;
    padding: 1rem;
    background: white;
    border-radius: 10px;
    margin-top: 1rem;
}

/* User Links */
.user-links {
    color: white;
}

.user-links h3 {
    margin-bottom: 1rem;
    color: #4ade80;
}

.links-list {
    display: grid;
    gap: 1rem;
}

.link-item {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.link-info h4 {
    color: #4ade80;
    margin-bottom: 0.25rem;
}

.link-info p {
    font-size: 0.9rem;
    opacity: 0.8;
}

.link-actions {
    display: flex;
    gap: 5px;
}

.link-actions .btn {
    padding: 6px 12px;
    font-size: 12px;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
}

.modal-content {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    margin: 10% auto;
    padding: 2rem;
    border-radius: 20px;
    width: 90%;
    max-width: 400px;
    position: relative;
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.close {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    position: absolute;
    right: 15px;
    top: 10px;
}

.close:hover {
    color: #000;
}

.modal h2 {
    margin-bottom: 1.5rem;
    text-align: center;
    color: #333;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: #555;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #4ade80;
}

.switch-form {
    text-align: center;
    margin-top: 1rem;
    color: #666;
}

.switch-form a {
    color: #4ade80;
    text-decoration: none;
    font-weight: 500;
}

.switch-form a:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    background: rgba(0, 0, 0, 0.2);
    color: white;
    text-align: center;
    padding: 1rem 0;
    margin-top: auto;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

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

    .form-options {
        flex-direction: column;
    }

    .result-url {
        flex-direction: column;
    }

    .link-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .nav {
        flex-direction: column;
        gap: 1rem;
    }
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #4ade80;
    animation: spin 1s ease-in-out infinite;
}

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

/* Success/Error Messages */
.message {
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 1rem;
    font-weight: 500;
}

.message.success {
    background: rgba(74, 222, 128, 0.2);
    color: #4ade80;
    border: 1px solid rgba(74, 222, 128, 0.3);
}

.message.error {
    background: rgba(239, 68, 68, 0.2);
    color: #ef4444;
    border: 1px solid rgba(239, 68, 68, 0.3);
}