/* --- VARIABELEN & RESET --- */
:root {
    --primary: #4F46E5;
    --primary-hover: #4338ca;
    --secondary: #10B981;
    --background: #F3F4F6;
    --surface: #FFFFFF;
    --text-main: #1F2937;
    --text-muted: #6B7280;
    --border: #E5E7EB;
    --danger: #EF4444;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --radius: 0.5rem;
    --font: 'Inter', sans-serif;
}

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

body {
    font-family: var(--font);
    background-color: var(--background);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
}

/* --- LAYOUT UTILS --- */
.container { max-width: 1000px; margin: 0 auto; padding: 0 1rem; }
.view { display: none; animation: fadeIn 0.3s ease-in-out; }
.view.active { display: block; }
.hidden { display: none !important; }

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

/* --- NAVBAR --- */
.navbar { background-color: var(--surface); border-bottom: 1px solid var(--border); padding: 1rem 0; }
.nav-content { display: flex; justify-content: space-between; align-items: center; }
.logo { font-weight: 700; font-size: 1.25rem; color: var(--primary); display: flex; align-items: center; gap: 0.5rem; }

/* --- BUTTONS & INPUTS --- */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 0.5rem 1rem; border-radius: var(--radius); font-weight: 500;
    cursor: pointer; border: none; transition: all 0.2s; font-family: inherit; gap: 0.5rem;
}
.btn-lg { padding: 0.75rem 1.5rem; font-size: 1.1rem; }
.btn-primary { background-color: var(--primary); color: white; }
.btn-primary:hover { background-color: var(--primary-hover); }
.btn-outline { background-color: transparent; border: 1px solid var(--border); color: var(--text-main); }
.btn-outline:hover { background-color: var(--background); }
.btn-text { background: none; color: var(--text-muted); }
.btn-text:hover { color: var(--text-main); }
.btn-success { background-color: var(--secondary); color: white; }

.input-field, .textarea-field {
    width: 100%; padding: 0.75rem; border: 1px solid var(--border);
    border-radius: var(--radius); font-family: inherit; font-size: 1rem;
}
.input-field:focus, .textarea-field:focus {
    outline: none; border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* --- HERO --- */
.hero { text-align: center; padding: 4rem 1rem; }
.hero h1 { font-size: 2.5rem; margin-bottom: 1rem; color: #111827; }
.hero p { font-size: 1.1rem; color: var(--text-muted); margin-bottom: 2rem; }
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 2rem; margin-top: 2rem; }
.feature-card { background: var(--surface); padding: 2rem; border-radius: var(--radius); text-align: center; box-shadow: var(--shadow); }
.feature-card i { font-size: 2rem; color: var(--primary); margin-bottom: 1rem; }

/* --- DASHBOARD --- */
.dashboard-header { display: flex; justify-content: space-between; align-items: center; margin: 2rem 0; }
.lists-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1.5rem; }
.list-card {
    background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
    padding: 1.5rem; transition: transform 0.2s; position: relative;
}
.list-card:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.list-actions { display: flex; gap: 0.5rem; margin-top: 1rem; }

/* --- EDITOR --- */
.form-group { margin-bottom: 1.5rem; }
.textarea-field { min-height: 300px; font-family: monospace; }
.editor-actions { display: flex; justify-content: space-between; align-items: center; background: var(--surface); padding: 1rem; border-radius: var(--radius); border: 1px solid var(--border); }

/* --- PRACTICE MODES --- */
.practice-modes { display: flex; gap: 1rem; margin-top: 2rem; }
.mode-card { flex: 1; background: var(--surface); padding: 2rem; border: 2px solid var(--border); border-radius: var(--radius); cursor: pointer; text-align: center; }
.mode-card:hover { border-color: var(--primary); background-color: #EEF2FF; }

/* --- FLASHCARDS --- */
.flashcard-container { perspective: 1000px; margin: 2rem auto; width: 100%; max-width: 500px; height: 300px; }
.flashcard { width: 100%; height: 100%; position: relative; cursor: pointer; }
.flashcard-inner { position: relative; width: 100%; height: 100%; text-align: center; transition: transform 0.6s; transform-style: preserve-3d; box-shadow: var(--shadow); border-radius: 1rem; }
.flashcard.flipped .flashcard-inner { transform: rotateY(180deg); }
.flashcard-front, .flashcard-back {
    position: absolute; width: 100%; height: 100%; -webkit-backface-visibility: hidden; backface-visibility: hidden;
    display: flex; flex-direction: column; justify-content: center; align-items: center;
    background-color: var(--surface); border-radius: 1rem; padding: 2rem; border: 1px solid var(--border);
}
.flashcard-back { transform: rotateY(180deg); background-color: #EEF2FF; color: var(--primary); }
.practice-controls { display: flex; justify-content: center; gap: 1rem; margin-top: 1rem; }

/* --- INPUT GAME --- */
.input-game-container { max-width: 600px; margin: 2rem auto; background: var(--surface); padding: 2rem; border-radius: var(--radius); box-shadow: var(--shadow); text-align: center; }
.feedback-msg { margin-top: 1rem; font-weight: 600; padding: 0.5rem; border-radius: var(--radius); }
.feedback-msg.correct { background-color: #D1FAE5; color: #065F46; }
.feedback-msg.wrong { background-color: #FEE2E2; color: #991B1B; }
.results-modal { position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%); background: var(--surface); padding: 3rem; border-radius: var(--radius); box-shadow: var(--shadow); text-align: center; z-index: 100; border: 1px solid var(--border); }

/* --- LOADING --- */
.loading-screen {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: var(--surface); display: flex; flex-direction: column; justify-content: center; align-items: center;
    z-index: 9999; transition: opacity 0.5s;
}
.loading-screen.fade-out { opacity: 0; pointer-events: none; }
.spinner { width: 40px; height: 40px; border: 4px solid var(--background); border-top: 4px solid var(--primary); border-radius: 50%; animation: spin 1s linear infinite; margin-bottom: 1rem; }
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }