:root {
    --primary-color: #0078d4;
    --primary-hover: #106ebe;
    --bg-color: #f5f5f5;
    --card-bg: #ffffff;
    --text-primary: #323131;
    --text-secondary: #605e5c;
    --text-accent: #0078d4;
    --border-color: #e0e0e0;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #1a1a1a;
        --card-bg: #2d2d2d;
        --text-primary: #ffffff;
        --text-secondary: #a0a0a0;
        --text-accent: #4da3ff;
        --border-color: #404040;
        --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
    }
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
    flex: 1;
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    background: var(--card-bg);
    padding: 8px;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.tab-btn {
    flex: 1;
    padding: 12px 16px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: 8px;
    transition: var(--transition);
}

.tab-btn:hover {
    background: var(--bg-color);
    color: var(--text-primary);
}

.tab-btn.active {
    background: var(--primary-color);
    color: white;
}

.display-card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 40px 20px;
    text-align: center;
    box-shadow: var(--shadow);
    min-height: 200px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.display-number {
    font-size: 4rem;
    font-weight: 700;
    color: var(--text-accent);
    line-height: 1.2;
    transition: var(--transition);
}

.display-label {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-top: 8px;
}

#header-emoji {
    cursor: pointer;
    user-select: none;
}

.settings-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 200;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.settings-overlay.visible {
    opacity: 1;
    visibility: visible;
}

.settings-panel {
    background: var(--card-bg);
    border-radius: 16px 16px 0 0;
    padding: 24px 20px 32px;
    width: 100%;
    max-width: 500px;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

.settings-overlay.visible .settings-panel {
    transform: translateY(0);
}

.settings-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.settings-header h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.settings-close {
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--text-secondary);
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.settings-close:hover {
    background: var(--bg-color);
    color: var(--text-primary);
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.input-group label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.input-group input[type="date"] {
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    background: var(--bg-color);
    color: var(--text-primary);
    outline: none;
    transition: var(--transition);
}

.input-group input[type="date"]:focus {
    border-color: var(--primary-color);
}

.input-group button {
    padding: 10px 16px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.input-group button:hover {
    background: var(--primary-hover);
}

.detail-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    margin-top: 20px;
}

.stat-item {
    background: var(--bg-color);
    padding: 16px;
    border-radius: 8px;
    text-align: center;
}

.stat-number {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-accent);
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

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

.display-number.animate {
    animation: fadeIn 0.3s ease;
}

@media (max-width: 480px) {
    .container {
        padding: 12px;
    }

    header h1 {
        font-size: 1.4rem;
    }

    header p {
        font-size: 0.8rem;
    }

    .display-number {
        font-size: 2.8rem;
    }

    .display-label {
        font-size: 0.95rem;
    }

    .tabs {
        gap: 4px;
        padding: 4px;
    }

    .tab-btn {
        padding: 8px 8px;
        font-size: 0.85rem;
    }

    .detail-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
        margin-top: 12px;
    }

    .stat-item {
        padding: 10px 8px;
    }

    .stat-number {
        font-size: 1.2rem;
    }

    .stat-label {
        font-size: 0.7rem;
    }

    .display-card {
        padding: 24px 12px;
        min-height: 140px;
    }
}