:root {
    /* Color Palette */
    --primary: #E21521;
    --primary-hover: #B5111A;
    --primary-light: #ffc2c5;
    --bg-color: #f8f9fa;
    --text-main: #212529;
    --text-muted: #868e96;
    --border-color: rgba(255, 255, 255, 0.4);
    --glass-bg: rgba(255, 255, 255, 0.9);
    --glass-shadow: 0 8px 32px 0 rgba(226, 21, 33, 0.1);
    
    /* Gradients */
    --bg-gradient: linear-gradient(135deg, #fdfbfb 0%, #ebedee 100%);
    --blob-1: #ff9a9e;
    --blob-2: #fecfef;
    --blob-3: #a1c4fd;
    
    /* Layout */
    --radius-lg: 24px;
    --radius-md: 12px;
    --radius-sm: 8px;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, 'Helvetica Neue', 'Segoe UI', 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', sans-serif;
}

body {
    background: var(--bg-color);
    color: var(--text-main);
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
    line-height: 1.6;
}

/* Background Animation */
.background-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
    background: var(--bg-gradient);
}

.blob {
    position: absolute;
    filter: blur(80px);
    border-radius: 50%;
    opacity: 0.6;
    animation: float 20s infinite ease-in-out alternate;
}

.blob-1 {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: var(--blob-1);
    animation-delay: 0s;
}

.blob-2 {
    bottom: -20%;
    right: -10%;
    width: 60vw;
    height: 60vw;
    background: var(--blob-2);
    animation-delay: -5s;
}

.blob-3 {
    top: 40%;
    left: 40%;
    width: 40vw;
    height: 40vw;
    background: var(--blob-3);
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(10%, 10%) scale(1.1); }
}

/* App Container */
.app-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 20px;
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.app-header {
    text-align: center;
    margin-bottom: 10px;
}

.logo-container {
    display: inline-block;
    cursor: pointer;
    margin-bottom: 4px;
    transition: var(--transition);
}

.logo-container:hover {
    transform: scale(1.05);
}

.logo {
    height: 14px;
    width: auto;
}

.app-header h1 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.02em;
}

.app-header .subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* Glass Panel */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    box-shadow: var(--glass-shadow);
    border-radius: var(--radius-lg);
    padding: 40px;
}

/* Form Sections */
.form-section {
    margin-bottom: 30px;
    opacity: 0;
    transform: translateY(20px);
    animation: slideUp 0.6s ease forwards;
}

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

.section-title {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 2px solid rgba(0,0,0,0.05);
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-title i {
    color: var(--primary);
}

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

.form-label {
    display: block;
    font-weight: 600;
    margin-bottom: 10px;
    font-size: 1rem;
}

.form-control {
    width: 100%;
    padding: 14px 16px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(0,0,0,0.1);
    background: rgba(255,255,255,0.7);
    font-size: 1rem;
    transition: var(--transition);
    outline: none;
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-light);
    background: #fff;
}

textarea.form-control {
    min-height: 100px;
    resize: vertical;
}

/* Options Grid (Radio/Checkbox) */
.options-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
}

.option-card {
    position: relative;
    display: flex;
    align-items: center;
    padding: 8px 12px;
    border-radius: var(--radius-md);
    border: none;
    background: transparent;
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    font-size: 0.85rem;
}

.option-card:hover {
    background: transparent;
    opacity: 0.8;
}

.option-card.active {
    border: none;
    background: transparent;
    color: var(--primary);
    font-weight: 600;
}

.option-card input[type="radio"],
.option-card input[type="checkbox"] {
    position: absolute;
    opacity: 0;
}

.option-indicator {
    width: 20px;
    height: 20px;
    border: 2px solid #ccc;
    margin-right: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    flex-shrink: 0;
}

.option-card input[type="radio"] ~ .option-indicator {
    border-radius: 50%;
}

.option-card input[type="checkbox"] ~ .option-indicator {
    border-radius: 4px;
}

.option-card.active .option-indicator {
    border-color: var(--primary);
    background: var(--primary);
}

.option-card.active input[type="radio"] ~ .option-indicator::after {
    content: '';
    width: 8px;
    height: 8px;
    background: #fff;
    border-radius: 50%;
}

.option-indicator i {
    display: none;
    font-size: 14px;
    color: #fff;
}

.option-card.active input[type="checkbox"] ~ .option-indicator i {
    display: block;
    animation: fadeIn 0.2s ease;
}

/* Direct Input */
.direct-input-container {
    margin-top: 10px;
    display: none;
    animation: fadeIn 0.3s ease;
}

.direct-input-container.show {
    display: block;
}

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

/* Submit Area */
.form-actions {
    margin-top: 40px;
    display: flex;
    justify-content: center;
    padding-bottom: 40px;
}

.btn {
    padding: 16px 32px;
    border-radius: 30px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    display: flex;
    align-items: center;
    gap: 8px;
    justify-content: center;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 15px rgba(226, 21, 33, 0.3);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(226, 21, 33, 0.4);
}

.btn-secondary {
    background: #fff;
    color: var(--text-main);
    border: 1px solid rgba(0,0,0,0.1);
}

.btn-secondary:hover {
    background: #f8f9fa;
}

.btn.w-full {
    width: 100%;
}

/* Modal Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(4px);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
}

.modal-overlay:not(.hidden) {
    opacity: 1;
    pointer-events: auto;
}

.modal-content {
    width: 90%;
    max-width: 600px;
    position: relative;
    transform: scale(0.95) translateY(20px);
    transition: var(--transition);
}

.modal-overlay:not(.hidden) .modal-content {
    transform: scale(1) translateY(0);
}

.modal-close {
    position: absolute;
    top: 20px;
    right: 20px;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: #333;
    font-weight: 700;
    transition: var(--transition);
}

.modal-close:hover {
    color: #000;
    transform: rotate(90deg);
}

.modal-content h2 {
    margin-bottom: 10px;
}

.modal-content p {
    color: var(--text-muted);
    margin-bottom: 24px;
}

.code-block {
    background: #282c34;
    color: #abb2bf;
    padding: 20px;
    border-radius: var(--radius-md);
    overflow-x: auto;
    max-height: 400px;
    overflow-y: auto;
    font-family: 'D2Coding', 'Fira Code', monospace;
    font-size: 0.9rem;
    margin-bottom: 24px;
}

.modal-actions {
    display: flex;
    gap: 16px;
    justify-content: flex-end;
}

/* Admin Login Panel */
.admin-login-panel {
    max-width: 400px;
    text-align: center;
}

.admin-icon {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 16px;
}

.admin-login-panel .input-group {
    margin-bottom: 24px;
}

.admin-login-panel input[type="password"] {
    width: 100%;
    padding: 14px 16px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(0,0,0,0.1);
    background: rgba(255,255,255,0.7);
    font-size: 1rem;
    transition: var(--transition);
    outline: none;
    box-sizing: border-box;
}

.admin-login-panel input[type="password"]:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-light);
}

/* Read Only Mode styles */
.read-only-view .form-control {
    background: rgba(0, 0, 0, 0.03);
    border: 1px solid rgba(0, 0, 0, 0.05);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    pointer-events: none;
    font-weight: 600;
    color: var(--text-main);
}
.read-only-view .options-grid {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.read-only-view .option-card {
    display: none;
}
.read-only-view .option-card.active {
    display: block;
    width: 100%;
    pointer-events: none;
    background: rgba(0, 0, 0, 0.03);
    border: 1px solid rgba(0, 0, 0, 0.05);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    color: var(--text-main);
    font-weight: 600;
}
.read-only-view .option-card.active .option-indicator {
    display: none;
}

/* Admin Mode Badge */
.admin-badge {
    position: absolute;
    top: 40px;
    right: -30px;
    background: #ff4757;
    color: white;
    padding: 4px 40px;
    font-size: 0.8rem;
    font-weight: bold;
    transform: rotate(45deg);
    box-shadow: 0 2px 10px rgba(255, 71, 87, 0.4);
    z-index: 10;
}

/* Mode Banner */
#mode-banner {
    display: none;
    background: var(--primary);
    color: white;
    text-align: center;
    padding: 10px;
    font-weight: 600;
    border-radius: var(--radius-md);
    margin-bottom: 20px;
    animation: fadeIn 0.3s ease;
}

/* Empty State Indicators */
.empty-indicator {
    display: none;
    width: 100%;
    padding: 10px 12px;
    border: none;
    color: var(--text-muted);
    font-size: 0.9rem;
    text-align: left;
    background: rgba(0,0,0,0.03);
    border-radius: var(--radius-sm);
}
.read-only-view .empty-indicator {
    display: block;
}
.read-only-view .form-control:placeholder-shown {
    border: none !important;
    border-radius: var(--radius-sm);
    background: rgba(0,0,0,0.03) !important;
    padding-left: 12px;
}

/* Checking Toggle - Switch Design */
.checking-toggle {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
}
.checking-toggle input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 36px;
    height: 20px;
    background: #e9ecef;
    border-radius: 20px;
    position: relative;
    cursor: pointer;
    outline: none;
    transition: var(--transition);
}
.checking-toggle input[type="checkbox"]::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    transition: var(--transition);
    box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}
.checking-toggle input[type="checkbox"]:checked {
    background: var(--primary);
}
.checking-toggle input[type="checkbox"]:checked::after {
    transform: translateX(16px);
}
.checking-toggle.disabled {
    pointer-events: none;
    opacity: 0.7;
}

/* Disabled Form Group for Checking */
.form-group.is-checking input[type="text"],
.form-group.is-checking input[type="url"],
.form-group.is-checking textarea,
.form-group.is-checking .options-grid {
    opacity: 0.3;
    pointer-events: none;
    filter: grayscale(100%);
}
.form-group.is-checking .direct-input-container {
    opacity: 0.3;
    pointer-events: none;
}

/* Responsive Design (Mobile / Low Res) */
@media (max-width: 768px) {
    .app-container {
        padding: 20px 15px;
    }
    
    h1 {
        font-size: 1.6rem;
    }
    
    .glass-panel, .form-section {
        padding: 24px 20px;
    }
    
    .options-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
    }
    
    .form-actions > div {
        flex-direction: column !important;
    }
    
    .form-actions .btn {
        width: 100%;
        padding: 14px 20px;
    }
    
    .option-card {
        padding: 10px;
        font-size: 0.9rem;
    }
    
    /* Top action buttons in view mode */
    #mode-banner + div {
        flex-direction: column !important;
        align-items: stretch !important;
    }
    #mode-banner + div .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .options-grid {
        grid-template-columns: 1fr;
    }
}