:root {
    --bg-color: #111;
    --text-color: #eee;
    --accent-color: #fff;
    --card-bg: #222;
    --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: "SF Mono", "Monaco", "Inconsolata", "Fira Mono", "Droid Sans Mono", "Source Code Pro", monospace;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-main);
    height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

#app {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    position: relative;
}

/* Intro Section */
#intro-section {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    text-align: center;
    z-index: 10;
    background: var(--bg-color);
}

.intro-title {
    font-size: 2rem;
    font-weight: bold;
    margin-bottom: 2rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

#intro-content {
    max-width: 600px;
    margin-bottom: 3rem;
}

.intro-line {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    opacity: 0;
    animation: fadeIn 1s forwards;
}

@keyframes fadeIn {
    to { opacity: 0.8; }
}

.btn {
    background: transparent;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 1rem 2rem;
    font-family: var(--font-mono);
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

.btn-small {
    background: transparent;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
    text-transform: uppercase;
}

.btn-small:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

/* Main Section */
#main-section {
    flex: 1;
    display: none; /* Hidden by default */
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    position: relative;
}

#technique-card {
    max-width: 800px;
    width: 100%;
    padding: 3rem;
    background: var(--card-bg);
    border: 1px solid #333;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    min-height: 400px;
    transition: opacity 0.3s ease;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.fade-out {
    opacity: 0;
}

.fade-in {
    opacity: 1;
}

#technique-id {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 1.5rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

#technique-text {
    font-size: 1.8rem;
    line-height: 1.5;
    font-weight: 300;
}

.controls {
    display: flex;
    gap: 1rem;
    margin-top: 3rem;
    flex-wrap: wrap;
    justify-content: center;
}

.control-btn {
    background: transparent;
    border: 1px solid #444;
    color: #aaa;
    width: 50px;
    height: 50px;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    border-radius: 50%;
    transition: all 0.2s;
}

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

.random-btn {
    width: auto;
    padding: 0 1.5rem;
    border-radius: 25px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    text-transform: uppercase;
}

/* List Section */
#list-section {
    flex: 1;
    display: none;
    flex-direction: column;
    padding: 2rem;
    overflow-y: auto;
    background: var(--bg-color);
}

.list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    position: sticky;
    top: 0;
    background: var(--bg-color);
    padding: 1rem 0;
    border-bottom: 1px solid #333;
    z-index: 5;
}

.list-header h2 {
    font-size: 1.2rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: normal;
}

#full-text-list {
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
}

.list-item {
    padding: 1.5rem 0;
    border-bottom: 1px solid #333;
    display: flex;
    gap: 1.5rem;
    cursor: pointer;
    transition: background 0.2s;
}

.list-item:hover {
    background: #1a1a1a;
}

.list-item-id {
    font-family: var(--font-mono);
    color: #666;
    min-width: 40px;
}

.list-item-text {
    line-height: 1.5;
    color: #ccc;
}

/* Progress Bar */
.progress-container {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: #222;
}

#progress-fill {
    height: 100%;
    background: var(--text-color);
    width: 0%;
    transition: width 0.3s ease;
}

/* Responsive */
@media (max-width: 600px) {
    .intro-title { font-size: 1.5rem; }
    .intro-line { font-size: 1rem; }
    #technique-text { font-size: 1.4rem; }
    #technique-card { padding: 1.5rem; min-height: 300px; }
    .controls { gap: 0.5rem; }
    .list-item { flex-direction: column; gap: 0.5rem; }
    #list-section { padding: 1rem; }
}