:root {
    --bg-color: #f5f5f7;
    --card-bg: rgba(255, 255, 255, 0.65);
    --text-primary: #1d1d1f;
    --text-secondary: #86868b;
    --accent-color: #0071e3;
    --accent-hover: #0077ed;
    --border-color: #d2d2d7;
    --input-bg: rgba(255, 255, 255, 0.8);
    --shadow-sm: 0 2px 5px rgba(0,0,0,0.05);
    --shadow-lg: 0 20px 40px rgba(0,0,0,0.1);
    --item-bg: rgba(255, 255, 255, 0.5);
}

body.dark-mode {
    --bg-color: #000000;
    --card-bg: rgba(28, 28, 30, 0.65);
    --text-primary: #f5f5f7;
    --text-secondary: #86868b;
    --accent-color: #2997ff;
    --accent-hover: #0071e3;
    --border-color: #424245;
    --input-bg: rgba(28, 28, 30, 0.8);
    --shadow-sm: 0 2px 5px rgba(0,0,0,0.5);
    --shadow-lg: 0 20px 40px rgba(0,0,0,0.6);
    --item-bg: rgba(44, 44, 46, 0.5);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    width: 90%;
    max-width: 600px;
    background-color: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
    text-align: center;
    border: 1px solid var(--border-color);
    transition: background-color 0.3s ease, border-color 0.3s ease;
    position: relative;
}

header {
    margin-bottom: 40px;
}

header h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -0.02em;
}

header p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.input-container {
    display: flex;
    gap: 12px;
    margin-bottom: 40px;
}

#keyword-input {
    flex: 1;
    padding: 16px 20px;
    border: 1px solid var(--border-color);
    background-color: var(--input-bg);
    border-radius: 12px;
    font-size: 1.1rem;
    color: var(--text-primary);
    transition: all 0.2s ease;
}

#keyword-input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(0, 113, 227, 0.15);
}

#generate-btn {
    padding: 16px 32px;
    border: none;
    background-color: var(--accent-color);
    color: #fff;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.1s ease;
}

#generate-btn:hover {
    background-color: var(--accent-hover);
}

#generate-btn:active {
    transform: scale(0.98);
}

.result-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 16px;
}

.team-name {
    background-color: var(--item-bg);
    padding: 16px;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
    text-align: center;
    transition: transform 0.2s ease, background-color 0.3s ease;
    cursor: default;
}

.team-name:hover {
    transform: translateY(-2px);
    background-color: var(--card-bg);
}

/* Theme Toggle Button */
.theme-toggle-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    color: var(--text-primary);
    transition: background-color 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle-btn:hover {
    background-color: var(--border-color);
}

.theme-toggle-btn svg {
    width: 24px;
    height: 24px;
    fill: currentColor;
}