.auth-section {
    padding: 100px 0;
    background: #f8f9fb;
    min-height: 80vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.auth-card {
    background: #fff;
    width: 100%;
    max-width: 550px;
    margin: 0 auto;
    padding: 60px;
    border-radius: 40px;
    border: 1px solid var(--border);
    box-shadow: 0 40px 100px rgba(0,0,0,0.03);
    transition: all 0.5s cubic-bezier(0.165, 0.84, 0.44, 1);
}

.auth-card.wide {
    max-width: 850px;
}

.auth-mode-selector {
    display: flex;
    gap: 12px;
    margin-bottom: 50px;
    justify-content: center;
}

.mode-btn {
    padding: 12px 28px;
    border: 1px solid var(--border);
    background: #fff;
    border-radius: 14px;
    font-family: inherit;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    color: var(--muted);
    transition: 0.3s;
}

.mode-btn.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.form-container {
    display: none;
    opacity: 0;
    transform: translateY(10px);
}

.form-container.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
    animation: fadeIn 0.4s ease forwards;
}

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

.auth-title { text-align: center; margin-bottom: 45px; }
.auth-title h1 { font-size: 38px; font-weight: 800; letter-spacing: -2px; margin-bottom: 10px; }
.auth-title p { color: var(--muted); font-size: 16px; font-weight: 500; }

.auth-form { display: flex; flex-direction: column; gap: 24px; }

.reg-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.reg-grid .full { grid-column: span 2; }

.input-unit { display: flex; flex-direction: column; gap: 8px; position: relative; }
.input-unit label {
    font-size: 11px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--muted);
    padding-left: 5px;
}

.input-unit input, .input-unit select {
    padding: 16px 20px;
    border-radius: 16px;
    border: 1px solid var(--border);
    background: #fcfcfc;
    font-family: inherit;
    font-size: 15px;
    font-weight: 600;
    transition: 0.3s;
}

.input-unit input:focus {
    border-color: var(--accent);
    background: #fff;
    box-shadow: 0 0 0 5px var(--accent-soft);
}

.err-text {
    font-size: 10px;
    color: #ff3b30;
    font-weight: 800;
    margin-top: 5px;
    display: none;
}

@media (max-width: 900px) {
    .auth-card, .auth-card.wide { 
        max-width: 100%; 
        padding: 50px 30px;
        border-radius: 30px;
    }
}

@media (max-width: 768px) {
    .auth-section {
        padding: 60px 0;
        min-height: auto;
    }
    
    .auth-card, .auth-card.wide { 
        padding: 40px 25px;
        border-radius: 24px;
    }
    
    .auth-title h1 {
        font-size: 28px;
    }
    
    .auth-title p {
        font-size: 14px;
    }
    
    .reg-grid { 
        grid-template-columns: 1fr; 
    }
    
    .reg-grid .full { 
        grid-column: span 1; 
    }
    
    .auth-mode-selector { 
        flex-direction: row;
        gap: 8px;
    }
    
    .mode-btn {
        padding: 10px 20px;
        font-size: 13px;
        flex: 1;
        text-align: center;
    }
    
    .input-unit input, .input-unit select {
        padding: 14px 16px;
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    .auth-section {
        padding: 40px 0;
    }
    
    .auth-card, .auth-card.wide { 
        padding: 30px 20px;
        border-radius: 20px;
    }
    
    .auth-title {
        margin-bottom: 30px;
    }
    
    .auth-title h1 {
        font-size: 24px;
        letter-spacing: -1px;
    }
    
    .auth-mode-selector {
        margin-bottom: 30px;
    }
    
    .auth-form {
        gap: 18px;
    }
}