:root {
    --bg-color: #f5f5f7; /* Apple's light gray background */
    --surface-color: rgba(255, 255, 255, 0.65); /* Frosted glass white */
    --surface-hover: rgba(255, 255, 255, 0.85);
    --border-color: rgba(0, 0, 0, 0.1);
    --border-highlight: #000000;
    --text-primary: #1d1d1f;
    --text-secondary: #86868b;
    --accent-color: #000000;
    --error-color: #ff3b30;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    
    --shadow-soft: 0 20px 40px rgba(0, 0, 0, 0.05);
    --glass-blur: blur(40px) saturate(180%);
}

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

body {
    font-family: 'Bai Jamjuree', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
    position: relative;
    -webkit-font-smoothing: antialiased;
}

/* Background Effects - Liquid Glass Refraction */
.background-effects {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    overflow: hidden;
    background: #f5f5f7;
}

.glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.5;
    animation: float 20s infinite alternate cubic-bezier(0.4, 0, 0.2, 1);
}

.glow-pink {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: #ff2d55;
}

.glow-blue {
    bottom: -10%;
    right: -10%;
    width: 60vw;
    height: 60vw;
    background: #007aff;
    animation-delay: -5s;
}

.glow-orange {
    top: 30%;
    left: 40%;
    width: 40vw;
    height: 40vw;
    background: #ff9500;
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(5%, 10%) scale(1.1); }
}

/* Container */
.app-container {
    width: 100%;
    max-width: 640px;
    padding: 40px 20px;
    z-index: 1;
}

/* Glass Panel Form Container */
.glass-panel {
    background: var(--surface-color);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid rgba(255, 255, 255, 0.4);
    border-radius: 24px;
    padding: 40px 48px;
    box-shadow: var(--shadow-soft), inset 0 0 0 1px rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

/* Header */
.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

.logo {
    height: 32px;
    /* Invert logo if it's white to show on light background */
    filter: invert(1);
}

.progress-container {
    width: 100%;
    height: 6px;
    background-color: rgba(0, 0, 0, 0.05);
    border-radius: 999px;
    overflow: hidden;
    margin-bottom: 15px;
}

.progress-bar {
    height: 100%;
    background: var(--accent-color);
    width: 20%;
    transition: width 0.6s cubic-bezier(0.25, 0.8, 0.25, 1);
    border-radius: 999px;
}

.step-indicator {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: 40px;
}

/* Form Styles */
.form-step {
    display: none;
    opacity: 0;
    transform: translateY(10px);
    transition: var(--transition);
}

.form-step.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
    animation: fadeIn 0.4s forwards cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-weight: 400;
}

.input-group {
    margin-bottom: 28px;
}

.input-group > label {
    display: block;
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

/* Text Inputs */
.text-input {
    width: 100%;
    background: rgba(255, 255, 255, 0.5);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 14px 16px;
    border-radius: 12px;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.02);
}

.text-input::placeholder {
    color: var(--text-secondary);
}

.text-input:focus {
    outline: none;
    border-color: var(--accent-color);
    background: #fff;
    box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.05);
}

textarea.text-input {
    resize: vertical;
    min-height: 80px;
}

/* Radio Buttons Styling */
.radio-group {
    display: flex;
    gap: 12px;
}

.row-flex {
    flex-direction: row;
}

.column-flex {
    flex-direction: column;
}

/* Radio Cards (for long options) */
.radio-card {
    position: relative;
    display: block;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.5);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    transition: var(--transition);
    overflow: hidden;
}

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

.card-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding: 16px;
}

.card-content strong {
    display: block;
    font-size: 1rem;
    color: var(--text-primary);
    margin-bottom: 4px;
    font-weight: 600;
}

.card-content p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.4;
    margin: 0;
}

.checkmark {
    color: var(--accent-color);
    opacity: 0;
    transform: scale(0.5);
    transition: var(--transition);
    flex-shrink: 0;
    margin-left: 12px;
}

.radio-card:hover {
    background: #ffffff;
    border-color: rgba(0, 0, 0, 0.2);
}

/* Selected State for Cards */
.radio-card.selected {
    background: #ffffff;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 1px var(--accent-color);
}

.radio-card.selected .checkmark {
    opacity: 1;
    transform: scale(1);
}

/* Radio Pills (for short Yes/No options) */
.radio-pill {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.5);
    border: 1px solid var(--border-color);
    padding: 12px 24px;
    border-radius: 999px;
    transition: var(--transition);
    flex: 1;
    text-align: center;
}

.radio-pill input[type="radio"] {
    position: absolute;
    opacity: 0;
}

.radio-pill span {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
}

.radio-pill:hover {
    background: #ffffff;
    border-color: rgba(0, 0, 0, 0.2);
}

.radio-pill.selected {
    background: #ffffff;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 1px var(--accent-color);
}

/* Custom Slider */
.slider-container {
    padding: 20px 0 10px;
}

.slider-value-display {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 20px;
    font-family: inherit;
    letter-spacing: -0.02em;
}

.slider-value-display .currency {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-right: 4px;
}

.custom-slider {
    -webkit-appearance: none;
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: rgba(0, 0, 0, 0.1);
    outline: none;
    transition: var(--transition);
    position: relative;
    z-index: 1;
}

.custom-slider::-webkit-slider-runnable-track {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    cursor: pointer;
    background: transparent;
}

.custom-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: #ffffff;
    cursor: pointer;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2), inset 0 0 0 1px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    margin-top: -8px; /* Center thumb on track */
    position: relative;
    z-index: 2;
}

.custom-slider::-moz-range-thumb {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: #ffffff;
    cursor: pointer;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2), inset 0 0 0 1px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    border: none;
}

.custom-slider::-webkit-slider-thumb:hover {
    transform: scale(1.15);
}

.custom-slider::-moz-range-thumb:hover {
    transform: scale(1.15);
}

.custom-slider:focus::-webkit-slider-thumb {
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2), 0 0 0 4px rgba(0, 0, 0, 0.1);
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    margin-top: 12px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Buttons */
.form-navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid rgba(0, 0, 0, 0.05);
}

.nav-right {
    display: flex;
    gap: 12px;
    margin-left: auto;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 999px;
    font-family: inherit;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--accent-color);
    color: #ffffff;
}

.btn-primary:hover {
    background: #333333;
    transform: scale(1.02);
}

.btn-outline {
    background: #ffffff;
    color: var(--text-primary);
    border-color: var(--border-color);
}

.btn-outline:hover {
    background: #f5f5f7;
    border-color: rgba(0, 0, 0, 0.2);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    padding: 10px;
}

.btn-ghost:hover {
    color: var(--error-color);
    background: rgba(255, 59, 48, 0.1);
}

.hidden {
    display: none !important;
}

/* Responsive */
@media (max-width: 640px) {
    .glass-panel {
        padding: 30px 20px;
        border-radius: 20px;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .radio-group.row-flex {
        flex-direction: column;
    }

    .form-navigation {
        flex-direction: column-reverse;
        gap: 20px;
    }

    .nav-right {
        width: 100%;
        justify-content: space-between;
        margin-left: 0;
    }
    
    .btn {
        width: 100%;
    }
    
    #reset-btn {
        width: 100%;
    }
}

/* Form Validation Styles */
.input-error {
    border-color: var(--error-color) !important;
    animation: shake 0.5s;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}