:root {
    --primary-color: #2c3e50;
    /* Navy */
    --accent-color: #27ae60;
    /* Green */
    --bg-color: #f5f7fa;
    --card-bg: #ffffff;
    --text-color: #333333;
    --border-color: #e1e4e8;
    --input-bg: #f8f9fa;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    --radius: 12px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
    font-size: 16px;
    height: 100vh;
    display: flex;
    justify-content: center;
}

.app-container {
    width: 100%;
    max-width: 480px;
    background-color: var(--card-bg);
    height: 100%;
    display: flex;
    flex-direction: column;
    position: relative;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
}

.app-header {
    padding: 20px;
    background-color: var(--card-bg);
    /* border-bottom: 1px solid var(--border-color); */
    /* Removed border for cleaner tab blend */
    z-index: 10;
}

.app-header h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 4px;
}

.app-header p {
    font-size: 14px;
    color: #666;
}

/* Tab Navigation - Enhanced for Contrast */
.tab-container {
    display: flex;
    padding: 0 20px;
    margin-bottom: 10px;
    gap: 10px;
    /* Space between tabs */
}

.tab-btn {
    flex: 1;
    padding: 12px;
    text-align: center;
    font-size: 15px;
    font-weight: 600;
    color: #666;
    cursor: pointer;
    background-color: #f0f0f0;
    /* Default gray bg */
    border-radius: 12px;
    /* Rounded corners */
    transition: all 0.2s;
}

.tab-btn.active {
    background-color: var(--primary-color);
    /* Navy bg */
    color: #fff;
    /* White text */
    box-shadow: 0 4px 6px rgba(44, 62, 80, 0.2);
    transform: translateY(-1px);
}

.app-content {
    flex: 1;
    overflow-y: auto;
    padding: 0 20px 20px 20px;
}

/* Form Styles */
.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 8px;
}

/* Inputs */
input[type="text"],
input[type="tel"],
input[type="number"],
textarea {
    width: 100%;
    padding: 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    background-color: var(--input-bg);
    font-size: 16px;
    font-family: inherit;
    transition: all 0.2s;
    outline: none;
}

input:focus,
textarea:focus {
    border-color: var(--primary-color);
    background-color: #fff;
    box-shadow: 0 0 0 2px rgba(44, 62, 80, 0.1);
}

textarea {
    resize: none;
}

/* Chips Selection */
.select-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.select-chips input {
    display: none;
}

.select-chips label {
    padding: 10px 16px;
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    color: #555;
    cursor: pointer;
    margin: 0;
    transition: all 0.2s;
}

.select-chips input:checked+label {
    background-color: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
    box-shadow: 0 2px 4px rgba(44, 62, 80, 0.2);
}

/* Trade Types */
.trade-types {
    display: flex;
    gap: 12px;
}

.trade-option {
    flex: 1;
}

.trade-option input {
    display: none;
}

.trade-option label {
    display: block;
    text-align: center;
    padding: 12px;
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.trade-option input:checked+label {
    border-color: var(--primary-color);
    background-color: #eef2f7;
    color: var(--primary-color);
    font-weight: 700;
}

/* Price Inputs */
.price-inputs {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

/* Footer & Button (Fixed) */
.app-footer {
    width: 100%;
    padding: 16px 20px;
    background-color: transparent;
    margin-top: 20px;
}

.submit-btn {
    width: 100%;
    padding: 16px;
    background-color: #007bff;
    color: #ffffff;
    border: none;
    border-radius: var(--radius);
    font-size: 17px;
    font-weight: 700;
    cursor: pointer;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.1s;
}

.submit-btn:active {
    transform: scale(0.98);
}

/* Sections */
.tab-content {
    display: none;
    animation: fadeIn 0.3s;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(5px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Privacy Section */
.privacy-section {
    margin-top: 20px;
    border-top: 1px solid var(--border-color);
    padding-top: 20px;
    font-size: 13px;
    color: #666;
}

details {
    cursor: pointer;
}

summary {
    display: flex;
    justify-content: space-between;
    outline: none;
    font-weight: 500;
}

summary span {
    font-size: 11px;
    color: #999;
}

.privacy-content {
    margin-top: 10px;
    padding: 12px;
    background-color: var(--input-bg);
    border-radius: 8px;
    font-size: 12px;
    line-height: 1.6;
}

.privacy-note {
    color: var(--primary-color);
    margin-top: 8px;
}