:root {
    --bg-color: #f8fafb;
    --card-bg: #ffffff;
    --text-main: #333333;
    --text-muted: #666666;
    --brand-green: #01894d;
    --brand-orange: #f39800;
    --accent-color: #f0fdf4;
    --border-color: #e5e7eb;
    --primary-color: #01894d;
    --primary-hover: #00703e;
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --transition: all 0.3s ease;
    --radius: 8px;
}

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

body {
    font-family: 'Noto Sans JP', 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    min-height: 100vh;
}

/* Header Design */
.main-header {
    background-color: var(--brand-green);
    border-bottom: 2px solid var(--brand-orange);
    padding: 15px 0;
    color: #ffffff;
    width: 100%;
    position: sticky;
    top: 0;
    z-index: 100;
}

.main-header-inner {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.title-icon {
    width: 28px;
    height: 28px;
}

.brand-logo {
    font-weight: 800;
    font-size: 1.3rem;
    color: #ffffff;
}

.btn-home {
    background-color: rgba(255, 255, 255, 0.2);
    color: #fff;
    text-decoration: none;
    padding: 6px 16px;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 600;
    transition: var(--transition);
}

.btn-home:hover {
    background-color: rgba(255, 255, 255, 0.3);
}

.container {
    max-width: 1100px;
    width: 100%;
    padding: 24px;
    margin: 0 auto;
}

/* Info Section (Site Description) */
.info-section {
    background-color: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 24px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.info-header {
    width: 100%;
    padding: 15px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    background-color: #f8fafb;
    border: none;
    transition: all 0.2s;
}

.info-header:hover {
    background-color: #f1f3f5;
}

.info-header h2 {
    font-size: 1.1rem;
    color: var(--brand-green);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
}

.toggle-icon {
    width: 20px;
    height: 20px;
    transition: transform 0.3s;
    fill: #666;
}

.info-section.collapsed .toggle-icon {
    transform: rotate(-180deg);
}

.info-content {
    padding: 24px;
    border-top: 1px solid var(--border-color);
    display: block;
}

.info-section.collapsed .info-content {
    display: none;
}

.usage-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin: 20px 0;
}

.usage-step {
    background-color: var(--accent-color);
    padding: 15px;
    border-radius: 8px;
    position: relative;
    padding-left: 45px;
}

.usage-step::before {
    content: attr(data-step);
    position: absolute;
    left: 12px;
    top: 12px;
    width: 24px;
    height: 24px;
    background-color: var(--brand-green);
    color: #fff;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: 800;
    font-size: 0.8rem;
}

.disclaimer {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px dashed var(--border-color);
}

/* Tool Layout */
.tool-layout {
    display: flex;
    gap: 24px;
    align-items: flex-start;
}

.settings-panel {
    width: 350px;
    flex-shrink: 0;
}

.preview-panel {
    flex-grow: 1;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: var(--shadow-sm);
}

.form-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--brand-green);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-number {
    background-color: var(--brand-orange);
    color: #fff;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 0.9rem;
    font-weight: 800;
}

.input-group {
    margin-bottom: 16px;
}

.input-row {
    display: flex;
    gap: 12px;
}

.input-row .input-group {
    flex: 1;
}

label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text-muted);
}

input[type="number"],
input[type="text"] {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
}

input:focus {
    outline: none;
    border-color: var(--brand-green);
    box-shadow: 0 0 0 3px rgba(1, 137, 77, 0.1);
}

input[type="color"] {
    width: 100%;
    height: 42px;
    padding: 2px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
}

small {
    display: block;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 4px;
}

.actions {
    margin-top: 20px;
}

.download-btn {
    width: 100%;
    background-color: var(--brand-orange);
    color: #fff;
    border: none;
    padding: 14px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    transition: var(--transition);
}

.download-btn:hover {
    background-color: #e08a00;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Preview Card */
.preview-card {
    min-height: 500px;
    display: flex;
    flex-direction: column;
}

.canvas-container {
    flex-grow: 1;
    background-color: #eee;
    border-radius: 6px;
    overflow: auto;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    min-height: 400px;
    border: 1px inset var(--border-color);
}

canvas {
    background-color: #fff;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
    max-width: 100%;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background-color: #333;
    color: #fff;
    padding: 12px 24px;
    border-radius: 30px;
    font-size: 0.9rem;
    transition: transform 0.3s ease;
    z-index: 1000;
    box-shadow: var(--shadow-md);
}

.toast.show {
    transform: translateX(-50%) translateY(0);
}

@media (max-width: 900px) {
    .tool-layout {
        flex-direction: column;
    }

    .settings-panel {
        width: 100%;
    }
}

@media (max-width: 600px) {
    .container {
        padding: 12px;
    }
}