:root[data-theme="light"] {
    --bg-color: #f5f5f5;
    --card-bg: #ffffff;
    --text-color: #333333;
    --border-color: #e0e0e0;
    --input-bg: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --hover-color: #f0f0f0;
    --click-bg: #e8f5e9;
    --click-color: #27ae60;
}

:root[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --card-bg: #2d2d2d;
    --text-color: #ffffff;
    --border-color: #404040;
    --input-bg: #3d3d3d;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --hover-color: #363636;
    --click-bg: #1e3320;
    --click-color: #4ade80;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
}

.theme-toggle {
    position: fixed;
    top: 20px;
    left: 20px;
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 10px;
    border-radius: 50%;
    transition: transform 0.3s, background-color 0.3s;
}

.theme-toggle:hover {
    background-color: var(--hover-color);
    transform: scale(1.1);
}

.container {
    max-width: 800px;
    width: 100%;
    margin: 50px auto;
    padding: 30px;
    background-color: var(--card-bg);
    border-radius: 15px;
    box-shadow: 0 8px 30px var(--shadow-color);
    animation: slideIn 0.5s ease-out;
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2.5rem;
    background: linear-gradient(45deg, #6366f1, #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: gradientFlow 3s ease infinite;
}

.url-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.input-group {
    position: relative;
    animation: fadeIn 0.5s ease-out;
}

input[type="url"] {
    width: 100%;
    padding: 15px;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    background-color: var(--input-bg);
    color: var(--text-color);
    font-size: 1rem;
    transition: all 0.3s ease;
}

input[type="url"]:focus {
    outline: none;
    border-color: #6366f1;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

button {
    padding: 15px 30px;
    border: none;
    border-radius: 10px;
    background: linear-gradient(45deg, #6366f1, #8b5cf6);
    color: white;
    font-size: 1rem;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(99, 102, 241, 0.4);
}

button:active {
    transform: translateY(0);
}

#result {
    margin-top: 20px;
    padding: 20px;
    border-radius: 10px;
    background-color: var(--input-bg);
    display: none;
    animation: slideUp 0.3s ease-out;
}

.short-url {
    word-break: break-all;
    color: #6366f1;
    font-weight: bold;
}

.copy-button {
    margin-top: 10px;
    background: transparent;
    border: 2px solid #6366f1;
    color: #6366f1;
}

.copy-button:hover {
    background: #6366f1;
    color: white;
}

.stats-card {
    background-color: var(--stat-bg);
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 20px;
    animation: fadeIn 0.5s ease-out;
}

.stat-item {
    margin-bottom: 20px;
    padding: 15px;
    border-bottom: 1px solid var(--border-color);
    transition: transform 0.3s;
}

.stat-item:hover {
    transform: translateX(10px);
}

.stat-label {
    font-weight: bold;
    color: var(--text-color);
    margin-bottom: 8px;
    font-size: 1.1rem;
}

.stat-value {
    color: #6366f1;
    word-break: break-all;
    font-size: 1.1rem;
    padding: 8px;
    border-radius: 8px;
    background-color: var(--card-bg);
}

.click-count {
    font-size: 1.5rem;
    color: var(--click-color);
    text-align: center;
    padding: 20px;
    background-color: var(--click-bg);
    border-radius: 12px;
    margin: 25px 0;
    animation: pulse 2s infinite;
}

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

@keyframes gradientFlow {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from {
        transform: translateY(10px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.02); }
    100% { transform: scale(1); }
}

/* Responsive */
@media (max-width: 600px) {
    .container {
        padding: 20px;
        margin: 20px;
    }

    h1 {
        font-size: 2rem;
    }

    .stats-card {
        padding: 15px;
    }

    .stat-item {
        padding: 10px;
    }
}