:root {
    /* Variables for Dark Mode (Default) */
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --text-main: #ffffff;
    --text-sub: #a0a0a0;
    --accent-color: #00ff88; /* Neon Green */
    --accent-hover: #00cc6a;
    --border-color: #333;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --font-main: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
}

[data-theme="light"] {
    --bg-color: #f4f4f5;
    --card-bg: #ffffff;
    --text-main: #18181b;
    --text-sub: #52525b;
    --accent-color: #6366f1; /* Indigo */
    --accent-hover: #4f46e5;
    --border-color: #e4e4e7;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-main);
    margin: 0;
    transition: background-color 0.3s ease, color 0.3s ease;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.navbar {
    width: 100%;
    max-width: 800px;
    padding: 1.5rem 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-sizing: border-box;
}

.logo {
    font-weight: 900;
    font-size: 1.5rem;
    letter-spacing: -0.05em;
    color: var(--accent-color);
}

.controls button {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 700;
    cursor: pointer;
    margin-left: 0.5rem;
    transition: all 0.2s;
}

.controls button:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.container {
    width: 100%;
    max-width: 600px;
    padding: 1rem;
    box-sizing: border-box;
    padding-bottom: 4rem;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    margin-top: 1rem;
}

h1 {
    font-size: 2.5rem;
    margin: 0;
    letter-spacing: -0.03em;
    background: linear-gradient(90deg, var(--text-main), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    color: var(--text-sub);
    margin-top: 0.5rem;
    font-size: 1rem;
}

/* Question Cards */
.question-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    animation: fadeInUp 0.5s ease backwards;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.question-text {
    font-size: 1.2rem;
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 1.2rem;
}

.option-label {
    display: flex;
    align-items: center;
    padding: 1rem;
    border-radius: 12px;
    background-color: rgba(128, 128, 128, 0.1);
    margin-bottom: 0.8rem;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

.option-label:hover {
    background-color: rgba(128, 128, 128, 0.2);
}

.option-label:active {
    transform: scale(0.98);
}

.option-label input {
    display: none;
}

/* Custom Radio */
.custom-radio {
    width: 20px;
    height: 20px;
    border: 2px solid var(--text-sub);
    border-radius: 50%;
    margin-right: 12px;
    position: relative;
    transition: border-color 0.2s;
}

.option-label input:checked + .custom-radio {
    border-color: var(--accent-color);
}

.option-label input:checked + .custom-radio::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 10px;
    height: 10px;
    background-color: var(--accent-color);
    border-radius: 50%;
}

.option-label input:checked ~ .option-text {
    color: var(--accent-color);
    font-weight: 700;
}

/* Submit Button */
#submit-btn {
    width: 100%;
    padding: 1.2rem;
    background-color: var(--accent-color);
    color: #000; /* Always black text on neon/indigo for contrast */
    border: none;
    border-radius: 16px;
    font-size: 1.2rem;
    font-weight: 900;
    cursor: pointer;
    transition: transform 0.2s, filter 0.2s;
    margin-top: 1rem;
}

#submit-btn:hover {
    filter: brightness(1.1);
    transform: translateY(-2px);
}

/* Result Section */
#result-container {
    text-align: center;
    margin-top: 3rem;
    animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes popIn {
    from { opacity: 0; transform: scale(0.8); }
    to { opacity: 1; transform: scale(1); }
}

.result-box {
    background: var(--card-bg);
    border: 2px solid var(--accent-color);
    border-radius: 20px;
    padding: 2rem;
    margin: 1.5rem 0;
    box-shadow: 0 0 30px rgba(0, 255, 136, 0.2); /* Neon glow hint */
}

[data-theme="light"] .result-box {
    box-shadow: 0 10px 30px rgba(99, 102, 241, 0.3);
}

#mbti-type {
    font-size: 4rem;
    margin: 0;
    font-weight: 900;
    color: var(--accent-color);
    line-height: 1;
}

/* Result Form Styling */
.submit-form {
    margin: 2rem 0;
    padding: 1.5rem;
    background: rgba(128, 128, 128, 0.05);
    border-radius: 20px;
    border: 1px dashed var(--border-color);
}

.form-guide {
    font-size: 0.9rem;
    color: var(--text-sub);
    margin-bottom: 1rem;
}

.input-group {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.input-group input[type="email"] {
    flex: 1;
    min-width: 200px;
    padding: 0.8rem 1rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    background: var(--bg-color);
    color: var(--text-main);
    font-family: inherit;
    outline: none;
    transition: border-color 0.2s;
}

.input-group input[type="email"]:focus {
    border-color: var(--accent-color);
}

#send-form-btn {
    padding: 0.8rem 1.5rem;
    background: var(--accent-color);
    color: #000;
    border: none;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
}

#send-form-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

#form-status {
    margin-top: 1rem;
    font-size: 0.85rem;
    font-weight: 700;
}

.retry-btn {
    background: transparent;
    color: var(--text-sub);
    border: 1px solid var(--text-sub);
    padding: 0.8rem 2rem;
    border-radius: 30px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.2s;
}

.retry-btn:hover {
    color: var(--text-main);
    border-color: var(--text-main);
}

/* Comments Section */
.comments-section {
    margin-top: 5rem;
    padding-top: 3rem;
    border-top: 1px solid var(--border-color);
}