:root {
    --primary-color: #5a67d8;
    --primary-light: #7f9cf5;
    --primary-dark: #4c51bf;
    --secondary-color: #63b3ed;
    --text-color-dark: #2d3748;
    --text-color-light: #4a5568;
    --bg-color: #edf2f7;
    --card-bg: #ffffff;
    --shadow-light: #ffffff;
    --shadow-dark: #d4d9e3;
    --border-radius: 16px;
    --transition-speed: 0.3s ease;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    color: var(--text-color-dark);
    line-height: 1.6;
    padding: 20px;
    box-sizing: border-box;
}

.calculator-wrapper {
    background-color: var(--card-bg);
    padding: 40px;
    border-radius: var(--border-radius);
    box-shadow: 10px 10px 20px var(--shadow-dark), -10px -10px 20px var(--shadow-light);
    width: 100%;
    max-width: 550px;
    text-align: center;
    transition: transform var(--transition-speed);
}

.calculator-wrapper:hover {
    transform: translateY(-5px);
}

.calculator-header {
    margin-bottom: 30px;
}

.calculator-title {
    font-size: 2.2em;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 10px;
    background: linear-gradient(45deg, var(--primary-dark), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.calculator-subtitle {
    font-size: 1.1em;
    color: var(--text-color-light);
    margin-bottom: 0;
}

.input-group {
    margin-bottom: 25px;
    text-align: left;
}

.input-label {
    display: block;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-color-dark);
    font-size: 1.05em;
}

.modern-input {
    width: 100%;
    padding: 14px 18px;
    box-sizing: border-box;
    border: none;
    outline: none;
    border-radius: 10px;
    background-color: var(--bg-color);
    box-shadow: inset 4px 4px 8px var(--shadow-dark), inset -4px -4px 8px var(--shadow-light);
    font-size: 1.1em;
    color: var(--text-color-dark);
    transition: box-shadow var(--transition-speed);
}

.modern-input:focus {
    box-shadow: inset 2px 2px 4px var(--shadow-dark), inset -2px -2px 4px var(--shadow-light), 0 0 0 3px var(--primary-light);
}

.input-hint {
    font-size: 0.9em;
    color: var(--text-color-light);
    margin-top: 8px;
}

.ecpm-display {
    background: linear-gradient(90deg, var(--secondary-color), var(--primary-light));
    color: white;
    padding: 4px 10px;
    border-radius: 8px;
    font-weight: bold;
    font-size: 1em;
    margin-left: 8px;
    display: inline-block;
}

.modern-slider {
    -webkit-appearance: none;
    width: 100%;
    height: 10px;
    background: var(--bg-color);
    border-radius: 5px;
    outline: none;
    margin-top: 15px;
    box-shadow: inset 2px 2px 5px var(--shadow-dark), inset -2px -2px 5px var(--shadow-light);
    transition: box-shadow var(--transition-speed);
}

.modern-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 25px;
    height: 25px;
    border-radius: 50%;
    background: linear-gradient(45deg, var(--primary-light), var(--primary-color));
    cursor: grab;
    box-shadow: 2px 2px 5px var(--shadow-dark), -2px -2px 5px var(--shadow-light);
    transition: background var(--transition-speed), transform 0.1s ease;
}

.modern-slider::-webkit-slider-thumb:hover {
    transform: scale(1.1);
    background: linear-gradient(45deg, var(--primary-color), var(--primary-light));
}

.modern-slider::-moz-range-thumb {
    width: 25px;
    height: 25px;
    border-radius: 50%;
    background: linear-gradient(45deg, var(--primary-light), var(--primary-color));
    cursor: grab;
    border: none;
    box-shadow: 2px 2px 5px var(--shadow-dark), -2px -2px 5px var(--shadow-light);
    transition: background var(--transition-speed), transform 0.1s ease;
}

.modern-slider::-moz-range-thumb:hover {
    transform: scale(1.1);
    background: linear-gradient(45deg, var(--primary-color), var(--primary-light));
}

.country-presets {
    display: flex;
    gap: 10px;
    margin-top: 15px;
    margin-bottom: 10px;
}

.preset-btn {
    flex-grow: 1;
    background-color: var(--bg-color);
    border: none;
    padding: 8px 12px;
    border-radius: 8px;
    font-family: 'Inter', sans-serif;
    font-weight: 600;
    color: var(--text-color-light);
    cursor: pointer;
    box-shadow: 3px 3px 6px var(--shadow-dark), -3px -3px 6px var(--shadow-light);
    transition: all 0.2s ease-in-out;
}

.preset-btn:hover {
    color: var(--primary-color);
    box-shadow: 1px 1px 2px var(--shadow-dark), -1px -1px 2px var(--shadow-light);
}

.preset-btn:active {
    box-shadow: inset 2px 2px 4px var(--shadow-dark), inset -2px -2px 4px var(--shadow-light);
    transform: scale(0.98);
}

.modern-button {
    background: linear-gradient(45deg, var(--primary-light), var(--primary-color));
    color: #ffffff;
    border: none;
    padding: 16px 25px;
    border-radius: 12px;
    font-size: 1.2em;
    font-weight: 700;
    cursor: pointer;
    width: 100%;
    box-shadow: 6px 6px 12px var(--shadow-dark), -6px -6px 12px var(--shadow-light);
    transition: all var(--transition-speed);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-top: 30px;
}

.modern-button:hover {
    background: linear-gradient(45deg, var(--primary-color), var(--primary-dark));
    box-shadow: 3px 3px 6px var(--shadow-dark), -3px -3px 6px var(--shadow-light);
    transform: translateY(-2px);
}

.modern-button:active {
    transform: translateY(1px);
    box-shadow: inset 2px 2px 5px var(--shadow-dark), inset -2px -2px 5px var(--shadow-light);
}

.button-icon {
    font-size: 1.3em;
}

.result-card {
    margin-top: 40px;
    padding: 30px;
    background-color: var(--bg-color);
    border-radius: var(--border-radius);
    box-shadow: inset 5px 5px 10px var(--shadow-dark), inset -5px -5px 10px var(--shadow-light);
    text-align: center;
    transition: all 0.5s ease-out;
    opacity: 1;
    max-height: 300px;
    overflow: hidden;
}

.result-hidden {
    opacity: 0;
    max-height: 0;
    padding-top: 0;
    padding-bottom: 0;
    margin-top: 0;
    visibility: hidden;
}

.result-title {
    font-size: 1.4em;
    font-weight: 600;
    color: var(--primary-dark);
    margin-bottom: 15px;
}

.result-earnings {
    font-size: 3.2em;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 10px;
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.05em;
}

.result-info {
    font-size: 0.95em;
    color: var(--text-color-light);
    margin-top: 15px;
}

@media (max-width: 600px) {
    .calculator-wrapper {
        padding: 30px 20px;
        margin: 10px;
    }
    .calculator-title {
        font-size: 1.8em;
    }
    .calculator-subtitle {
        font-size: 1em;
    }
    .result-earnings {
        font-size: 2.5em;
    }
}