:root {
    --primary-color: #3498db;
    --secondary-color: #2980b9;
    --accent-color: #e74c3c;
    --light-color: #ecf0f1;
    --dark-color: #2c3e50;
    --text-color: #333;
    --border-radius: 12px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: linear-gradient(-45deg, #f5f7fa, #e4e8eb, #f5f7fa);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    transition: var(--transition);
}

/* Dynamic background classes */
body.thunderstorm {
    background: linear-gradient(to bottom, #0f2027, #203a43, #2c5364);
    color: white;
}

body.rainy {
    background: linear-gradient(to bottom, #3a7bd5, #00d2ff);
    color: white;
}

body.snowy {
    background: linear-gradient(to bottom, #e6e9f0, #eef1f5);
}

body.sunny {
    background: linear-gradient(to bottom, #ff7e5f, #feb47b);
}

body.cloudy {
    background: linear-gradient(to bottom, #bdc3c7, #2c3e50);
    color: white;
}

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

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

header {
    text-align: center;
    margin-bottom: 30px;
    padding: 25px;
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    backdrop-filter: blur(5px);
    transition: var(--transition);
}

body.thunderstorm header,
body.rainy header,
body.cloudy header {
    background-color: rgba(0, 0, 0, 0.7);
}

h1, h2 {
    color: var(--primary-color);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

h1 i {
    font-size: 1.2em;
}

.search-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

#search-input {
    padding: 12px 20px;
    border: 2px solid #ddd;
    border-radius: var(--border-radius);
    width: 300px;
    max-width: 100%;
    font-size: 16px;
    transition: var(--transition);
    flex-grow: 1;
}

#search-input:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

button {
    padding: 12px 18px;
    border: none;
    border-radius: var(--border-radius);
    background-color: var(--primary-color);
    color: white;
    cursor: pointer;
    font-size: 16px;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

button:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

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

button i {
    font-size: 1em;
}

.unit-toggle {
    display: flex;
    border-radius: var(--border-radius);
    overflow: hidden;
}

.unit-toggle button {
    border-radius: 0;
    padding: 12px 15px;
    min-width: 50px;
}

.unit-toggle button:first-child {
    border-top-left-radius: var(--border-radius);
    border-bottom-left-radius: var(--border-radius);
}

.unit-toggle button:last-child {
    border-top-right-radius: var(--border-radius);
    border-bottom-right-radius: var(--border-radius);
}

.unit-toggle button.active {
    background-color: var(--secondary-color);
    font-weight: bold;
}

.ripple {
    position: absolute;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.7);
    transform: scale(0);
    animation: ripple 0.6s linear;
    pointer-events: none;
}

@keyframes ripple {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

main {
    display: grid;
    grid-template-columns: 1fr;
    gap: 25px;
}

.weather-card {
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: var(--border-radius);
    padding: 25px;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    backdrop-filter: blur(5px);
}

body.thunderstorm .weather-card,
body.rainy .weather-card,
body.cloudy .weather-card {
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
}

.current-weather .weather-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    align-items: center;
}

.weather-icon {
    font-size: 4rem;
    margin: 15px 0;
    color: var(--primary-color);
    transition: transform 0.3s ease, color 0.3s ease;
}

.weather-icon:hover {
    transform: scale(1.1);
}

.temperature {
    font-size: 3rem;
    font-weight: bold;
    margin: 15px 0;
}

.weather-description {
    font-size: 1.2rem;
    text-transform: capitalize;
    margin-bottom: 10px;
}

.weather-details {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    text-align: left;
    margin-top: 25px;
}

.weather-details div {
    display: flex;
    align-items: center;
    gap: 10px;
}

.weather-details i {
    width: 20px;
    text-align: center;
    color: var(--primary-color);
}

.forecast-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
}

.forecast-day {
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: var(--border-radius);
    padding: 20px;
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: var(--transition);
}

body.thunderstorm .forecast-day,
body.rainy .forecast-day,
body.cloudy .forecast-day {
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
}

.forecast-day:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
}

.forecast-day h3 {
    margin-bottom: 10px;
    color: var(--primary-color);
}

.forecast-icon {
    font-size: 2.5rem;
    margin: 15px 0;
    color: var(--primary-color);
}

.forecast-temp {
    display: flex;
    justify-content: space-around;
    margin-top: 15px;
    font-size: 1.1rem;
}

.high-temp {
    color: var(--accent-color);
    font-weight: bold;
}

.low-temp {
    color: var(--primary-color);
}

.weather-alerts {
    margin-bottom: 25px;
}

.alert-card {
    background-color: #fff3cd;
    border-left: 5px solid #ffc107;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.alert-card:hover {
    transform: translateX(5px);
}

.alert-card h3 {
    color: #856404;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.alert-card p {
    color: #856404;
    margin-bottom: 5px;
}

.no-alerts {
    text-align: center;
    padding: 30px;
    color: #666;
    font-style: italic;
}

/* Skeleton Loading */
.skeleton-loading {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem;
}

.skeleton-line, .skeleton-icon {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: 4px;
}

body.thunderstorm .skeleton-line,
body.thunderstorm .skeleton-icon,
body.rainy .skeleton-line,
body.rainy .skeleton-icon,
body.cloudy .skeleton-line,
body.cloudy .skeleton-icon {
    background: linear-gradient(90deg, rgba(255,255,255,0.1) 25%, rgba(255,255,255,0.2) 50%, rgba(255,255,255,0.1) 75%);
}

.skeleton-line {
    height: 1rem;
}

.skeleton-icon {
    width: 4rem;
    height: 4rem;
    margin: 1rem auto;
    border-radius: 50%;
}

@keyframes shimmer {
    0% { background-position: 200% 0 }
    100% { background-position: -200% 0 }
}

.error-message {
    color: var(--accent-color);
    text-align: center;
    padding: 30px;
    font-weight: bold;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.error-message i {
    font-size: 2.5rem;
}

footer {
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    color: #666;
    font-size: 14px;
}

#last-updated {
    font-style: italic;
    color: var(--primary-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .current-weather .weather-card {
        grid-template-columns: 1fr;
    }
    
    .weather-details {
        grid-template-columns: 1fr;
    }
    
    .forecast-container {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }
}

@media (max-width: 480px) {
    .search-container {
        flex-direction: column;
    }
    
    #search-input {
        width: 100%;
    }
    
    button {
        width: 100%;
    }
    
    .unit-toggle {
        width: 100%;
        display: flex;
    }
    
    .unit-toggle button {
        flex: 1;
    }
    
    .forecast-container {
        grid-template-columns: 1fr;
    }
    }