:root {
    --bg-dark: #0f1115;
    --card-bg: rgba(25, 28, 35, 0.6);
    --card-border: rgba(255, 255, 255, 0.08);
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --accent-1: #ec4899;
    --accent-2: #8b5cf6;
    --success: #10b981;
    --success-bg: rgba(16, 185, 129, 0.1);
    --error: #ef4444;
    --error-bg: rgba(239, 68, 68, 0.1);
}

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

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow-x: hidden;
}

/* Background Shapes for modern aesthetic */
.background-shapes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.5;
    animation: float 20s infinite alternate;
}

.shape-1 {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: radial-gradient(circle, var(--accent-2) 0%, transparent 70%);
    animation-delay: 0s;
}

.shape-2 {
    bottom: -20%;
    right: -10%;
    width: 60vw;
    height: 60vw;
    background: radial-gradient(circle, var(--primary) 0%, transparent 70%);
    animation-delay: -5s;
}

.shape-3 {
    top: 40%;
    left: 60%;
    width: 40vw;
    height: 40vw;
    background: radial-gradient(circle, var(--accent-1) 0%, transparent 70%);
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) rotate(0deg); }
    100% { transform: translate(5%, 5%) rotate(10deg); }
}

.container {
    width: 100%;
    max-width: 800px;
    padding: 2rem;
    z-index: 1;
}

header {
    text-align: center;
    margin-bottom: 2.5rem;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.logo svg {
    color: var(--accent-1);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #fff, #a5b4fc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.05em;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
    font-weight: 300;
}

.glassmorphism {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

textarea {
    width: 100%;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    padding: 1.25rem;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1.1rem;
    line-height: 1.6;
    resize: vertical;
    transition: all 0.3s ease;
}

textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.15);
}

textarea::placeholder {
    color: rgba(156, 163, 175, 0.5);
}

.actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    border-radius: 12px;
    font-family: inherit;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
}

.primary-btn {
    background: linear-gradient(135deg, var(--primary), var(--accent-2));
    color: white;
    flex: 1;
    box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.39);
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

.primary-btn:active {
    transform: translateY(0);
}

.secondary-btn {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-main);
    border: 1px solid var(--card-border);
}

.secondary-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

.divider {
    height: 1px;
    background: var(--card-border);
    margin: 2.5rem 0;
}

.hidden {
    display: none !important;
}

#loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    padding: 2rem 0;
    color: var(--text-muted);
}

.spinner {
    width: 32px;
    height: 32px;
    border: 3px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.result-box {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    padding: 1.5rem;
    font-size: 1.25rem;
    line-height: 1.6;
    animation: fadeIn 0.4s ease-out forwards;
}

.corrected-word {
    color: var(--success);
    font-weight: 600;
    position: relative;
    cursor: help;
    text-decoration: underline;
    text-decoration-color: rgba(16, 185, 129, 0.4);
    text-decoration-thickness: 2px;
    text-underline-offset: 4px;
}

.changes-box {
    margin-top: 1.5rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 12px;
    padding: 1.25rem;
    animation: fadeIn 0.4s ease-out forwards;
    animation-delay: 0.1s;
}

.changes-box h3 {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

#corrections-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

#corrections-list li {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
}

.error-word {
    color: var(--error);
    text-decoration: line-through;
    opacity: 0.8;
}

.arrow {
    color: var(--text-muted);
}

.success-message {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1.25rem;
    background: var(--success-bg);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: 12px;
    color: var(--success);
    font-weight: 500;
    animation: fadeIn 0.4s ease-out forwards;
}

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

@media (max-width: 640px) {
    .container {
        padding: 1rem;
    }
    
    .glassmorphism {
        padding: 1.5rem;
    }
    
    .actions {
        flex-direction: column;
    }
}