:root {
    --primary-color: #4CAF50; /* メインカラー (緑) */
    --secondary-color: #f4f4f4; /* 背景色 */
    --font-color: #333;
    --border-color: #ddd;
    --holiday-color: #f29b9b;
    --full-color: #ff6b6b;
    --available-color: #98fb98;
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    background-color: var(--secondary-color);
    color: var(--font-color);
    margin: 0;
    padding: 20px;
    -webkit-tap-highlight-color: transparent;
}

.container {
    max-width: 500px;
    margin: 0 auto;
    background: #fff;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

header {
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 15px;
    margin-bottom: 20px;
}

header h1 {
    font-size: 24px;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.logo { height: 30px; }

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

.calendar-header button {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 36px;
    height: 36px;
    font-size: 20px;
    cursor: pointer;
    transition: background-color 0.2s;
}
.calendar-header button:hover { background-color: #f0f0f0; }
.calendar-header button:disabled { cursor: not-allowed; opacity: 0.5; }

#calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 5px;
}

.calendar-day, .weekday-header {
    text-align: center;
    padding: 10px 0;
    font-size: 14px;
}

.weekday-header { font-weight: bold; }
.weekday-header.sun { color: var(--full-color); }
.weekday-header.sat { color: #4a90e2; }

.calendar-day {
    border-radius: 8px;
    position: relative;
}

.day-number {
    font-size: 16px;
}

.day-status {
    font-size: 12px;
    font-weight: bold;
}

.calendar-day.other-month {
    color: #ccc;
}

.calendar-day.bookable {
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}
.calendar-day.bookable:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    background-color: #e8f5e9;
}

.calendar-day.holiday .day-status { color: var(--holiday-color); }
.calendar-day.full .day-status { color: var(--full-color); }
.calendar-day.available .day-status { color: var(--primary-color); }

/* モーダル */
.modal-overlay {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}
.modal-content {
    background: #fff;
    padding: 30px;
    border-radius: 12px;
    width: 90%;
    max-width: 400px;
    position: relative;
    box-shadow: 0 5px 20px rgba(0,0,0,0.2);
}
.close-btn {
    position: absolute;
    top: 15px; right: 15px;
    font-size: 28px;
    cursor: pointer;
    color: #aaa;
}
.form-group { margin-bottom: 20px; }
.form-group label { display: block; margin-bottom: 8px; font-weight: bold; }
.form-group input, .form-group select {
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    font-size: 16px;
    box-sizing: border-box;
}
.submit-btn {
    width: 100%;
    padding: 15px;
    background-color: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.2s;
}
.submit-btn:hover { background-color: #45a049; }
#form-message { margin-top: 15px; text-align: center; }